xref: /openbmc/linux/drivers/spi/spi-pl022.c (revision 23e2c2aa)
1 /*
2  * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
3  *
4  * Copyright (C) 2008-2012 ST-Ericsson AB
5  * Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
6  *
7  * Author: Linus Walleij <linus.walleij@stericsson.com>
8  *
9  * Initial version inspired by:
10  *	linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
11  * Initial adoption to PL022 by:
12  *      Sachin Verma <sachin.verma@st.com>
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  */
24 
25 #include <linux/init.h>
26 #include <linux/module.h>
27 #include <linux/device.h>
28 #include <linux/ioport.h>
29 #include <linux/errno.h>
30 #include <linux/interrupt.h>
31 #include <linux/spi/spi.h>
32 #include <linux/delay.h>
33 #include <linux/clk.h>
34 #include <linux/err.h>
35 #include <linux/amba/bus.h>
36 #include <linux/amba/pl022.h>
37 #include <linux/io.h>
38 #include <linux/slab.h>
39 #include <linux/dmaengine.h>
40 #include <linux/dma-mapping.h>
41 #include <linux/scatterlist.h>
42 #include <linux/pm_runtime.h>
43 #include <linux/gpio.h>
44 #include <linux/of_gpio.h>
45 #include <linux/pinctrl/consumer.h>
46 
47 /*
48  * This macro is used to define some register default values.
49  * reg is masked with mask, the OR:ed with an (again masked)
50  * val shifted sb steps to the left.
51  */
52 #define SSP_WRITE_BITS(reg, val, mask, sb) \
53  ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
54 
55 /*
56  * This macro is also used to define some default values.
57  * It will just shift val by sb steps to the left and mask
58  * the result with mask.
59  */
60 #define GEN_MASK_BITS(val, mask, sb) \
61  (((val)<<(sb)) & (mask))
62 
63 #define DRIVE_TX		0
64 #define DO_NOT_DRIVE_TX		1
65 
66 #define DO_NOT_QUEUE_DMA	0
67 #define QUEUE_DMA		1
68 
69 #define RX_TRANSFER		1
70 #define TX_TRANSFER		2
71 
72 /*
73  * Macros to access SSP Registers with their offsets
74  */
75 #define SSP_CR0(r)	(r + 0x000)
76 #define SSP_CR1(r)	(r + 0x004)
77 #define SSP_DR(r)	(r + 0x008)
78 #define SSP_SR(r)	(r + 0x00C)
79 #define SSP_CPSR(r)	(r + 0x010)
80 #define SSP_IMSC(r)	(r + 0x014)
81 #define SSP_RIS(r)	(r + 0x018)
82 #define SSP_MIS(r)	(r + 0x01C)
83 #define SSP_ICR(r)	(r + 0x020)
84 #define SSP_DMACR(r)	(r + 0x024)
85 #define SSP_ITCR(r)	(r + 0x080)
86 #define SSP_ITIP(r)	(r + 0x084)
87 #define SSP_ITOP(r)	(r + 0x088)
88 #define SSP_TDR(r)	(r + 0x08C)
89 
90 #define SSP_PID0(r)	(r + 0xFE0)
91 #define SSP_PID1(r)	(r + 0xFE4)
92 #define SSP_PID2(r)	(r + 0xFE8)
93 #define SSP_PID3(r)	(r + 0xFEC)
94 
95 #define SSP_CID0(r)	(r + 0xFF0)
96 #define SSP_CID1(r)	(r + 0xFF4)
97 #define SSP_CID2(r)	(r + 0xFF8)
98 #define SSP_CID3(r)	(r + 0xFFC)
99 
100 /*
101  * SSP Control Register 0  - SSP_CR0
102  */
103 #define SSP_CR0_MASK_DSS	(0x0FUL << 0)
104 #define SSP_CR0_MASK_FRF	(0x3UL << 4)
105 #define SSP_CR0_MASK_SPO	(0x1UL << 6)
106 #define SSP_CR0_MASK_SPH	(0x1UL << 7)
107 #define SSP_CR0_MASK_SCR	(0xFFUL << 8)
108 
109 /*
110  * The ST version of this block moves som bits
111  * in SSP_CR0 and extends it to 32 bits
112  */
113 #define SSP_CR0_MASK_DSS_ST	(0x1FUL << 0)
114 #define SSP_CR0_MASK_HALFDUP_ST	(0x1UL << 5)
115 #define SSP_CR0_MASK_CSS_ST	(0x1FUL << 16)
116 #define SSP_CR0_MASK_FRF_ST	(0x3UL << 21)
117 
118 /*
119  * SSP Control Register 0  - SSP_CR1
120  */
121 #define SSP_CR1_MASK_LBM	(0x1UL << 0)
122 #define SSP_CR1_MASK_SSE	(0x1UL << 1)
123 #define SSP_CR1_MASK_MS		(0x1UL << 2)
124 #define SSP_CR1_MASK_SOD	(0x1UL << 3)
125 
126 /*
127  * The ST version of this block adds some bits
128  * in SSP_CR1
129  */
130 #define SSP_CR1_MASK_RENDN_ST	(0x1UL << 4)
131 #define SSP_CR1_MASK_TENDN_ST	(0x1UL << 5)
132 #define SSP_CR1_MASK_MWAIT_ST	(0x1UL << 6)
133 #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
134 #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
135 /* This one is only in the PL023 variant */
136 #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
137 
138 /*
139  * SSP Status Register - SSP_SR
140  */
141 #define SSP_SR_MASK_TFE		(0x1UL << 0) /* Transmit FIFO empty */
142 #define SSP_SR_MASK_TNF		(0x1UL << 1) /* Transmit FIFO not full */
143 #define SSP_SR_MASK_RNE		(0x1UL << 2) /* Receive FIFO not empty */
144 #define SSP_SR_MASK_RFF		(0x1UL << 3) /* Receive FIFO full */
145 #define SSP_SR_MASK_BSY		(0x1UL << 4) /* Busy Flag */
146 
147 /*
148  * SSP Clock Prescale Register  - SSP_CPSR
149  */
150 #define SSP_CPSR_MASK_CPSDVSR	(0xFFUL << 0)
151 
152 /*
153  * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
154  */
155 #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
156 #define SSP_IMSC_MASK_RTIM  (0x1UL << 1) /* Receive timeout Interrupt mask */
157 #define SSP_IMSC_MASK_RXIM  (0x1UL << 2) /* Receive FIFO Interrupt mask */
158 #define SSP_IMSC_MASK_TXIM  (0x1UL << 3) /* Transmit FIFO Interrupt mask */
159 
160 /*
161  * SSP Raw Interrupt Status Register - SSP_RIS
162  */
163 /* Receive Overrun Raw Interrupt status */
164 #define SSP_RIS_MASK_RORRIS		(0x1UL << 0)
165 /* Receive Timeout Raw Interrupt status */
166 #define SSP_RIS_MASK_RTRIS		(0x1UL << 1)
167 /* Receive FIFO Raw Interrupt status */
168 #define SSP_RIS_MASK_RXRIS		(0x1UL << 2)
169 /* Transmit FIFO Raw Interrupt status */
170 #define SSP_RIS_MASK_TXRIS		(0x1UL << 3)
171 
172 /*
173  * SSP Masked Interrupt Status Register - SSP_MIS
174  */
175 /* Receive Overrun Masked Interrupt status */
176 #define SSP_MIS_MASK_RORMIS		(0x1UL << 0)
177 /* Receive Timeout Masked Interrupt status */
178 #define SSP_MIS_MASK_RTMIS		(0x1UL << 1)
179 /* Receive FIFO Masked Interrupt status */
180 #define SSP_MIS_MASK_RXMIS		(0x1UL << 2)
181 /* Transmit FIFO Masked Interrupt status */
182 #define SSP_MIS_MASK_TXMIS		(0x1UL << 3)
183 
184 /*
185  * SSP Interrupt Clear Register - SSP_ICR
186  */
187 /* Receive Overrun Raw Clear Interrupt bit */
188 #define SSP_ICR_MASK_RORIC		(0x1UL << 0)
189 /* Receive Timeout Clear Interrupt bit */
190 #define SSP_ICR_MASK_RTIC		(0x1UL << 1)
191 
192 /*
193  * SSP DMA Control Register - SSP_DMACR
194  */
195 /* Receive DMA Enable bit */
196 #define SSP_DMACR_MASK_RXDMAE		(0x1UL << 0)
197 /* Transmit DMA Enable bit */
198 #define SSP_DMACR_MASK_TXDMAE		(0x1UL << 1)
199 
200 /*
201  * SSP Integration Test control Register - SSP_ITCR
202  */
203 #define SSP_ITCR_MASK_ITEN		(0x1UL << 0)
204 #define SSP_ITCR_MASK_TESTFIFO		(0x1UL << 1)
205 
206 /*
207  * SSP Integration Test Input Register - SSP_ITIP
208  */
209 #define ITIP_MASK_SSPRXD		 (0x1UL << 0)
210 #define ITIP_MASK_SSPFSSIN		 (0x1UL << 1)
211 #define ITIP_MASK_SSPCLKIN		 (0x1UL << 2)
212 #define ITIP_MASK_RXDMAC		 (0x1UL << 3)
213 #define ITIP_MASK_TXDMAC		 (0x1UL << 4)
214 #define ITIP_MASK_SSPTXDIN		 (0x1UL << 5)
215 
216 /*
217  * SSP Integration Test output Register - SSP_ITOP
218  */
219 #define ITOP_MASK_SSPTXD		 (0x1UL << 0)
220 #define ITOP_MASK_SSPFSSOUT		 (0x1UL << 1)
221 #define ITOP_MASK_SSPCLKOUT		 (0x1UL << 2)
222 #define ITOP_MASK_SSPOEn		 (0x1UL << 3)
223 #define ITOP_MASK_SSPCTLOEn		 (0x1UL << 4)
224 #define ITOP_MASK_RORINTR		 (0x1UL << 5)
225 #define ITOP_MASK_RTINTR		 (0x1UL << 6)
226 #define ITOP_MASK_RXINTR		 (0x1UL << 7)
227 #define ITOP_MASK_TXINTR		 (0x1UL << 8)
228 #define ITOP_MASK_INTR			 (0x1UL << 9)
229 #define ITOP_MASK_RXDMABREQ		 (0x1UL << 10)
230 #define ITOP_MASK_RXDMASREQ		 (0x1UL << 11)
231 #define ITOP_MASK_TXDMABREQ		 (0x1UL << 12)
232 #define ITOP_MASK_TXDMASREQ		 (0x1UL << 13)
233 
234 /*
235  * SSP Test Data Register - SSP_TDR
236  */
237 #define TDR_MASK_TESTDATA		(0xFFFFFFFF)
238 
239 /*
240  * Message State
241  * we use the spi_message.state (void *) pointer to
242  * hold a single state value, that's why all this
243  * (void *) casting is done here.
244  */
245 #define STATE_START			((void *) 0)
246 #define STATE_RUNNING			((void *) 1)
247 #define STATE_DONE			((void *) 2)
248 #define STATE_ERROR			((void *) -1)
249 
250 /*
251  * SSP State - Whether Enabled or Disabled
252  */
253 #define SSP_DISABLED			(0)
254 #define SSP_ENABLED			(1)
255 
256 /*
257  * SSP DMA State - Whether DMA Enabled or Disabled
258  */
259 #define SSP_DMA_DISABLED		(0)
260 #define SSP_DMA_ENABLED			(1)
261 
262 /*
263  * SSP Clock Defaults
264  */
265 #define SSP_DEFAULT_CLKRATE 0x2
266 #define SSP_DEFAULT_PRESCALE 0x40
267 
268 /*
269  * SSP Clock Parameter ranges
270  */
271 #define CPSDVR_MIN 0x02
272 #define CPSDVR_MAX 0xFE
273 #define SCR_MIN 0x00
274 #define SCR_MAX 0xFF
275 
276 /*
277  * SSP Interrupt related Macros
278  */
279 #define DEFAULT_SSP_REG_IMSC  0x0UL
280 #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
281 #define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
282 
283 #define CLEAR_ALL_INTERRUPTS  0x3
284 
285 #define SPI_POLLING_TIMEOUT 1000
286 
287 /*
288  * The type of reading going on on this chip
289  */
290 enum ssp_reading {
291 	READING_NULL,
292 	READING_U8,
293 	READING_U16,
294 	READING_U32
295 };
296 
297 /**
298  * The type of writing going on on this chip
299  */
300 enum ssp_writing {
301 	WRITING_NULL,
302 	WRITING_U8,
303 	WRITING_U16,
304 	WRITING_U32
305 };
306 
307 /**
308  * struct vendor_data - vendor-specific config parameters
309  * for PL022 derivates
310  * @fifodepth: depth of FIFOs (both)
311  * @max_bpw: maximum number of bits per word
312  * @unidir: supports unidirection transfers
313  * @extended_cr: 32 bit wide control register 0 with extra
314  * features and extra features in CR1 as found in the ST variants
315  * @pl023: supports a subset of the ST extensions called "PL023"
316  */
317 struct vendor_data {
318 	int fifodepth;
319 	int max_bpw;
320 	bool unidir;
321 	bool extended_cr;
322 	bool pl023;
323 	bool loopback;
324 };
325 
326 /**
327  * struct pl022 - This is the private SSP driver data structure
328  * @adev: AMBA device model hookup
329  * @vendor: vendor data for the IP block
330  * @phybase: the physical memory where the SSP device resides
331  * @virtbase: the virtual memory where the SSP is mapped
332  * @clk: outgoing clock "SPICLK" for the SPI bus
333  * @master: SPI framework hookup
334  * @master_info: controller-specific data from machine setup
335  * @kworker: thread struct for message pump
336  * @kworker_task: pointer to task for message pump kworker thread
337  * @pump_messages: work struct for scheduling work to the message pump
338  * @queue_lock: spinlock to syncronise access to message queue
339  * @queue: message queue
340  * @busy: message pump is busy
341  * @running: message pump is running
342  * @pump_transfers: Tasklet used in Interrupt Transfer mode
343  * @cur_msg: Pointer to current spi_message being processed
344  * @cur_transfer: Pointer to current spi_transfer
345  * @cur_chip: pointer to current clients chip(assigned from controller_state)
346  * @next_msg_cs_active: the next message in the queue has been examined
347  *  and it was found that it uses the same chip select as the previous
348  *  message, so we left it active after the previous transfer, and it's
349  *  active already.
350  * @tx: current position in TX buffer to be read
351  * @tx_end: end position in TX buffer to be read
352  * @rx: current position in RX buffer to be written
353  * @rx_end: end position in RX buffer to be written
354  * @read: the type of read currently going on
355  * @write: the type of write currently going on
356  * @exp_fifo_level: expected FIFO level
357  * @dma_rx_channel: optional channel for RX DMA
358  * @dma_tx_channel: optional channel for TX DMA
359  * @sgt_rx: scattertable for the RX transfer
360  * @sgt_tx: scattertable for the TX transfer
361  * @dummypage: a dummy page used for driving data on the bus with DMA
362  * @cur_cs: current chip select (gpio)
363  * @chipselects: list of chipselects (gpios)
364  */
365 struct pl022 {
366 	struct amba_device		*adev;
367 	struct vendor_data		*vendor;
368 	resource_size_t			phybase;
369 	void __iomem			*virtbase;
370 	struct clk			*clk;
371 	struct spi_master		*master;
372 	struct pl022_ssp_controller	*master_info;
373 	/* Message per-transfer pump */
374 	struct tasklet_struct		pump_transfers;
375 	struct spi_message		*cur_msg;
376 	struct spi_transfer		*cur_transfer;
377 	struct chip_data		*cur_chip;
378 	bool				next_msg_cs_active;
379 	void				*tx;
380 	void				*tx_end;
381 	void				*rx;
382 	void				*rx_end;
383 	enum ssp_reading		read;
384 	enum ssp_writing		write;
385 	u32				exp_fifo_level;
386 	enum ssp_rx_level_trig		rx_lev_trig;
387 	enum ssp_tx_level_trig		tx_lev_trig;
388 	/* DMA settings */
389 #ifdef CONFIG_DMA_ENGINE
390 	struct dma_chan			*dma_rx_channel;
391 	struct dma_chan			*dma_tx_channel;
392 	struct sg_table			sgt_rx;
393 	struct sg_table			sgt_tx;
394 	char				*dummypage;
395 	bool				dma_running;
396 #endif
397 	int cur_cs;
398 	int *chipselects;
399 };
400 
401 /**
402  * struct chip_data - To maintain runtime state of SSP for each client chip
403  * @cr0: Value of control register CR0 of SSP - on later ST variants this
404  *       register is 32 bits wide rather than just 16
405  * @cr1: Value of control register CR1 of SSP
406  * @dmacr: Value of DMA control Register of SSP
407  * @cpsr: Value of Clock prescale register
408  * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
409  * @enable_dma: Whether to enable DMA or not
410  * @read: function ptr to be used to read when doing xfer for this chip
411  * @write: function ptr to be used to write when doing xfer for this chip
412  * @cs_control: chip select callback provided by chip
413  * @xfer_type: polling/interrupt/DMA
414  *
415  * Runtime state of the SSP controller, maintained per chip,
416  * This would be set according to the current message that would be served
417  */
418 struct chip_data {
419 	u32 cr0;
420 	u16 cr1;
421 	u16 dmacr;
422 	u16 cpsr;
423 	u8 n_bytes;
424 	bool enable_dma;
425 	enum ssp_reading read;
426 	enum ssp_writing write;
427 	void (*cs_control) (u32 command);
428 	int xfer_type;
429 };
430 
431 /**
432  * null_cs_control - Dummy chip select function
433  * @command: select/delect the chip
434  *
435  * If no chip select function is provided by client this is used as dummy
436  * chip select
437  */
438 static void null_cs_control(u32 command)
439 {
440 	pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
441 }
442 
443 static void pl022_cs_control(struct pl022 *pl022, u32 command)
444 {
445 	if (gpio_is_valid(pl022->cur_cs))
446 		gpio_set_value(pl022->cur_cs, command);
447 	else
448 		pl022->cur_chip->cs_control(command);
449 }
450 
451 /**
452  * giveback - current spi_message is over, schedule next message and call
453  * callback of this message. Assumes that caller already
454  * set message->status; dma and pio irqs are blocked
455  * @pl022: SSP driver private data structure
456  */
457 static void giveback(struct pl022 *pl022)
458 {
459 	struct spi_transfer *last_transfer;
460 	pl022->next_msg_cs_active = false;
461 
462 	last_transfer = list_last_entry(&pl022->cur_msg->transfers,
463 					struct spi_transfer, transfer_list);
464 
465 	/* Delay if requested before any change in chip select */
466 	if (last_transfer->delay_usecs)
467 		/*
468 		 * FIXME: This runs in interrupt context.
469 		 * Is this really smart?
470 		 */
471 		udelay(last_transfer->delay_usecs);
472 
473 	if (!last_transfer->cs_change) {
474 		struct spi_message *next_msg;
475 
476 		/*
477 		 * cs_change was not set. We can keep the chip select
478 		 * enabled if there is message in the queue and it is
479 		 * for the same spi device.
480 		 *
481 		 * We cannot postpone this until pump_messages, because
482 		 * after calling msg->complete (below) the driver that
483 		 * sent the current message could be unloaded, which
484 		 * could invalidate the cs_control() callback...
485 		 */
486 		/* get a pointer to the next message, if any */
487 		next_msg = spi_get_next_queued_message(pl022->master);
488 
489 		/*
490 		 * see if the next and current messages point
491 		 * to the same spi device.
492 		 */
493 		if (next_msg && next_msg->spi != pl022->cur_msg->spi)
494 			next_msg = NULL;
495 		if (!next_msg || pl022->cur_msg->state == STATE_ERROR)
496 			pl022_cs_control(pl022, SSP_CHIP_DESELECT);
497 		else
498 			pl022->next_msg_cs_active = true;
499 
500 	}
501 
502 	pl022->cur_msg = NULL;
503 	pl022->cur_transfer = NULL;
504 	pl022->cur_chip = NULL;
505 	spi_finalize_current_message(pl022->master);
506 
507 	/* disable the SPI/SSP operation */
508 	writew((readw(SSP_CR1(pl022->virtbase)) &
509 		(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
510 
511 }
512 
513 /**
514  * flush - flush the FIFO to reach a clean state
515  * @pl022: SSP driver private data structure
516  */
517 static int flush(struct pl022 *pl022)
518 {
519 	unsigned long limit = loops_per_jiffy << 1;
520 
521 	dev_dbg(&pl022->adev->dev, "flush\n");
522 	do {
523 		while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
524 			readw(SSP_DR(pl022->virtbase));
525 	} while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
526 
527 	pl022->exp_fifo_level = 0;
528 
529 	return limit;
530 }
531 
532 /**
533  * restore_state - Load configuration of current chip
534  * @pl022: SSP driver private data structure
535  */
536 static void restore_state(struct pl022 *pl022)
537 {
538 	struct chip_data *chip = pl022->cur_chip;
539 
540 	if (pl022->vendor->extended_cr)
541 		writel(chip->cr0, SSP_CR0(pl022->virtbase));
542 	else
543 		writew(chip->cr0, SSP_CR0(pl022->virtbase));
544 	writew(chip->cr1, SSP_CR1(pl022->virtbase));
545 	writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
546 	writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
547 	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
548 	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
549 }
550 
551 /*
552  * Default SSP Register Values
553  */
554 #define DEFAULT_SSP_REG_CR0 ( \
555 	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0)	| \
556 	GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
557 	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
558 	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
559 	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
560 )
561 
562 /* ST versions have slightly different bit layout */
563 #define DEFAULT_SSP_REG_CR0_ST ( \
564 	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0)	| \
565 	GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
566 	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
567 	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
568 	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
569 	GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16)	| \
570 	GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
571 )
572 
573 /* The PL023 version is slightly different again */
574 #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
575 	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0)	| \
576 	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
577 	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
578 	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
579 )
580 
581 #define DEFAULT_SSP_REG_CR1 ( \
582 	GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
583 	GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
584 	GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
585 	GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
586 )
587 
588 /* ST versions extend this register to use all 16 bits */
589 #define DEFAULT_SSP_REG_CR1_ST ( \
590 	DEFAULT_SSP_REG_CR1 | \
591 	GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
592 	GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
593 	GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
594 	GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
595 	GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
596 )
597 
598 /*
599  * The PL023 variant has further differences: no loopback mode, no microwire
600  * support, and a new clock feedback delay setting.
601  */
602 #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
603 	GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
604 	GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
605 	GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
606 	GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
607 	GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
608 	GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
609 	GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
610 	GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
611 )
612 
613 #define DEFAULT_SSP_REG_CPSR ( \
614 	GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
615 )
616 
617 #define DEFAULT_SSP_REG_DMACR (\
618 	GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
619 	GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
620 )
621 
622 /**
623  * load_ssp_default_config - Load default configuration for SSP
624  * @pl022: SSP driver private data structure
625  */
626 static void load_ssp_default_config(struct pl022 *pl022)
627 {
628 	if (pl022->vendor->pl023) {
629 		writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
630 		writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
631 	} else if (pl022->vendor->extended_cr) {
632 		writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
633 		writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
634 	} else {
635 		writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
636 		writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
637 	}
638 	writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
639 	writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
640 	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
641 	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
642 }
643 
644 /**
645  * This will write to TX and read from RX according to the parameters
646  * set in pl022.
647  */
648 static void readwriter(struct pl022 *pl022)
649 {
650 
651 	/*
652 	 * The FIFO depth is different between primecell variants.
653 	 * I believe filling in too much in the FIFO might cause
654 	 * errons in 8bit wide transfers on ARM variants (just 8 words
655 	 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
656 	 *
657 	 * To prevent this issue, the TX FIFO is only filled to the
658 	 * unused RX FIFO fill length, regardless of what the TX
659 	 * FIFO status flag indicates.
660 	 */
661 	dev_dbg(&pl022->adev->dev,
662 		"%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
663 		__func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
664 
665 	/* Read as much as you can */
666 	while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
667 	       && (pl022->rx < pl022->rx_end)) {
668 		switch (pl022->read) {
669 		case READING_NULL:
670 			readw(SSP_DR(pl022->virtbase));
671 			break;
672 		case READING_U8:
673 			*(u8 *) (pl022->rx) =
674 				readw(SSP_DR(pl022->virtbase)) & 0xFFU;
675 			break;
676 		case READING_U16:
677 			*(u16 *) (pl022->rx) =
678 				(u16) readw(SSP_DR(pl022->virtbase));
679 			break;
680 		case READING_U32:
681 			*(u32 *) (pl022->rx) =
682 				readl(SSP_DR(pl022->virtbase));
683 			break;
684 		}
685 		pl022->rx += (pl022->cur_chip->n_bytes);
686 		pl022->exp_fifo_level--;
687 	}
688 	/*
689 	 * Write as much as possible up to the RX FIFO size
690 	 */
691 	while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
692 	       && (pl022->tx < pl022->tx_end)) {
693 		switch (pl022->write) {
694 		case WRITING_NULL:
695 			writew(0x0, SSP_DR(pl022->virtbase));
696 			break;
697 		case WRITING_U8:
698 			writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
699 			break;
700 		case WRITING_U16:
701 			writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
702 			break;
703 		case WRITING_U32:
704 			writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
705 			break;
706 		}
707 		pl022->tx += (pl022->cur_chip->n_bytes);
708 		pl022->exp_fifo_level++;
709 		/*
710 		 * This inner reader takes care of things appearing in the RX
711 		 * FIFO as we're transmitting. This will happen a lot since the
712 		 * clock starts running when you put things into the TX FIFO,
713 		 * and then things are continuously clocked into the RX FIFO.
714 		 */
715 		while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
716 		       && (pl022->rx < pl022->rx_end)) {
717 			switch (pl022->read) {
718 			case READING_NULL:
719 				readw(SSP_DR(pl022->virtbase));
720 				break;
721 			case READING_U8:
722 				*(u8 *) (pl022->rx) =
723 					readw(SSP_DR(pl022->virtbase)) & 0xFFU;
724 				break;
725 			case READING_U16:
726 				*(u16 *) (pl022->rx) =
727 					(u16) readw(SSP_DR(pl022->virtbase));
728 				break;
729 			case READING_U32:
730 				*(u32 *) (pl022->rx) =
731 					readl(SSP_DR(pl022->virtbase));
732 				break;
733 			}
734 			pl022->rx += (pl022->cur_chip->n_bytes);
735 			pl022->exp_fifo_level--;
736 		}
737 	}
738 	/*
739 	 * When we exit here the TX FIFO should be full and the RX FIFO
740 	 * should be empty
741 	 */
742 }
743 
744 /**
745  * next_transfer - Move to the Next transfer in the current spi message
746  * @pl022: SSP driver private data structure
747  *
748  * This function moves though the linked list of spi transfers in the
749  * current spi message and returns with the state of current spi
750  * message i.e whether its last transfer is done(STATE_DONE) or
751  * Next transfer is ready(STATE_RUNNING)
752  */
753 static void *next_transfer(struct pl022 *pl022)
754 {
755 	struct spi_message *msg = pl022->cur_msg;
756 	struct spi_transfer *trans = pl022->cur_transfer;
757 
758 	/* Move to next transfer */
759 	if (trans->transfer_list.next != &msg->transfers) {
760 		pl022->cur_transfer =
761 		    list_entry(trans->transfer_list.next,
762 			       struct spi_transfer, transfer_list);
763 		return STATE_RUNNING;
764 	}
765 	return STATE_DONE;
766 }
767 
768 /*
769  * This DMA functionality is only compiled in if we have
770  * access to the generic DMA devices/DMA engine.
771  */
772 #ifdef CONFIG_DMA_ENGINE
773 static void unmap_free_dma_scatter(struct pl022 *pl022)
774 {
775 	/* Unmap and free the SG tables */
776 	dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
777 		     pl022->sgt_tx.nents, DMA_TO_DEVICE);
778 	dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
779 		     pl022->sgt_rx.nents, DMA_FROM_DEVICE);
780 	sg_free_table(&pl022->sgt_rx);
781 	sg_free_table(&pl022->sgt_tx);
782 }
783 
784 static void dma_callback(void *data)
785 {
786 	struct pl022 *pl022 = data;
787 	struct spi_message *msg = pl022->cur_msg;
788 
789 	BUG_ON(!pl022->sgt_rx.sgl);
790 
791 #ifdef VERBOSE_DEBUG
792 	/*
793 	 * Optionally dump out buffers to inspect contents, this is
794 	 * good if you want to convince yourself that the loopback
795 	 * read/write contents are the same, when adopting to a new
796 	 * DMA engine.
797 	 */
798 	{
799 		struct scatterlist *sg;
800 		unsigned int i;
801 
802 		dma_sync_sg_for_cpu(&pl022->adev->dev,
803 				    pl022->sgt_rx.sgl,
804 				    pl022->sgt_rx.nents,
805 				    DMA_FROM_DEVICE);
806 
807 		for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
808 			dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
809 			print_hex_dump(KERN_ERR, "SPI RX: ",
810 				       DUMP_PREFIX_OFFSET,
811 				       16,
812 				       1,
813 				       sg_virt(sg),
814 				       sg_dma_len(sg),
815 				       1);
816 		}
817 		for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
818 			dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
819 			print_hex_dump(KERN_ERR, "SPI TX: ",
820 				       DUMP_PREFIX_OFFSET,
821 				       16,
822 				       1,
823 				       sg_virt(sg),
824 				       sg_dma_len(sg),
825 				       1);
826 		}
827 	}
828 #endif
829 
830 	unmap_free_dma_scatter(pl022);
831 
832 	/* Update total bytes transferred */
833 	msg->actual_length += pl022->cur_transfer->len;
834 	if (pl022->cur_transfer->cs_change)
835 		pl022_cs_control(pl022, SSP_CHIP_DESELECT);
836 
837 	/* Move to next transfer */
838 	msg->state = next_transfer(pl022);
839 	tasklet_schedule(&pl022->pump_transfers);
840 }
841 
842 static void setup_dma_scatter(struct pl022 *pl022,
843 			      void *buffer,
844 			      unsigned int length,
845 			      struct sg_table *sgtab)
846 {
847 	struct scatterlist *sg;
848 	int bytesleft = length;
849 	void *bufp = buffer;
850 	int mapbytes;
851 	int i;
852 
853 	if (buffer) {
854 		for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
855 			/*
856 			 * If there are less bytes left than what fits
857 			 * in the current page (plus page alignment offset)
858 			 * we just feed in this, else we stuff in as much
859 			 * as we can.
860 			 */
861 			if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
862 				mapbytes = bytesleft;
863 			else
864 				mapbytes = PAGE_SIZE - offset_in_page(bufp);
865 			sg_set_page(sg, virt_to_page(bufp),
866 				    mapbytes, offset_in_page(bufp));
867 			bufp += mapbytes;
868 			bytesleft -= mapbytes;
869 			dev_dbg(&pl022->adev->dev,
870 				"set RX/TX target page @ %p, %d bytes, %d left\n",
871 				bufp, mapbytes, bytesleft);
872 		}
873 	} else {
874 		/* Map the dummy buffer on every page */
875 		for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
876 			if (bytesleft < PAGE_SIZE)
877 				mapbytes = bytesleft;
878 			else
879 				mapbytes = PAGE_SIZE;
880 			sg_set_page(sg, virt_to_page(pl022->dummypage),
881 				    mapbytes, 0);
882 			bytesleft -= mapbytes;
883 			dev_dbg(&pl022->adev->dev,
884 				"set RX/TX to dummy page %d bytes, %d left\n",
885 				mapbytes, bytesleft);
886 
887 		}
888 	}
889 	BUG_ON(bytesleft);
890 }
891 
892 /**
893  * configure_dma - configures the channels for the next transfer
894  * @pl022: SSP driver's private data structure
895  */
896 static int configure_dma(struct pl022 *pl022)
897 {
898 	struct dma_slave_config rx_conf = {
899 		.src_addr = SSP_DR(pl022->phybase),
900 		.direction = DMA_DEV_TO_MEM,
901 		.device_fc = false,
902 	};
903 	struct dma_slave_config tx_conf = {
904 		.dst_addr = SSP_DR(pl022->phybase),
905 		.direction = DMA_MEM_TO_DEV,
906 		.device_fc = false,
907 	};
908 	unsigned int pages;
909 	int ret;
910 	int rx_sglen, tx_sglen;
911 	struct dma_chan *rxchan = pl022->dma_rx_channel;
912 	struct dma_chan *txchan = pl022->dma_tx_channel;
913 	struct dma_async_tx_descriptor *rxdesc;
914 	struct dma_async_tx_descriptor *txdesc;
915 
916 	/* Check that the channels are available */
917 	if (!rxchan || !txchan)
918 		return -ENODEV;
919 
920 	/*
921 	 * If supplied, the DMA burstsize should equal the FIFO trigger level.
922 	 * Notice that the DMA engine uses one-to-one mapping. Since we can
923 	 * not trigger on 2 elements this needs explicit mapping rather than
924 	 * calculation.
925 	 */
926 	switch (pl022->rx_lev_trig) {
927 	case SSP_RX_1_OR_MORE_ELEM:
928 		rx_conf.src_maxburst = 1;
929 		break;
930 	case SSP_RX_4_OR_MORE_ELEM:
931 		rx_conf.src_maxburst = 4;
932 		break;
933 	case SSP_RX_8_OR_MORE_ELEM:
934 		rx_conf.src_maxburst = 8;
935 		break;
936 	case SSP_RX_16_OR_MORE_ELEM:
937 		rx_conf.src_maxburst = 16;
938 		break;
939 	case SSP_RX_32_OR_MORE_ELEM:
940 		rx_conf.src_maxburst = 32;
941 		break;
942 	default:
943 		rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
944 		break;
945 	}
946 
947 	switch (pl022->tx_lev_trig) {
948 	case SSP_TX_1_OR_MORE_EMPTY_LOC:
949 		tx_conf.dst_maxburst = 1;
950 		break;
951 	case SSP_TX_4_OR_MORE_EMPTY_LOC:
952 		tx_conf.dst_maxburst = 4;
953 		break;
954 	case SSP_TX_8_OR_MORE_EMPTY_LOC:
955 		tx_conf.dst_maxburst = 8;
956 		break;
957 	case SSP_TX_16_OR_MORE_EMPTY_LOC:
958 		tx_conf.dst_maxburst = 16;
959 		break;
960 	case SSP_TX_32_OR_MORE_EMPTY_LOC:
961 		tx_conf.dst_maxburst = 32;
962 		break;
963 	default:
964 		tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
965 		break;
966 	}
967 
968 	switch (pl022->read) {
969 	case READING_NULL:
970 		/* Use the same as for writing */
971 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
972 		break;
973 	case READING_U8:
974 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
975 		break;
976 	case READING_U16:
977 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
978 		break;
979 	case READING_U32:
980 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
981 		break;
982 	}
983 
984 	switch (pl022->write) {
985 	case WRITING_NULL:
986 		/* Use the same as for reading */
987 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
988 		break;
989 	case WRITING_U8:
990 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
991 		break;
992 	case WRITING_U16:
993 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
994 		break;
995 	case WRITING_U32:
996 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
997 		break;
998 	}
999 
1000 	/* SPI pecularity: we need to read and write the same width */
1001 	if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1002 		rx_conf.src_addr_width = tx_conf.dst_addr_width;
1003 	if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1004 		tx_conf.dst_addr_width = rx_conf.src_addr_width;
1005 	BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1006 
1007 	dmaengine_slave_config(rxchan, &rx_conf);
1008 	dmaengine_slave_config(txchan, &tx_conf);
1009 
1010 	/* Create sglists for the transfers */
1011 	pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1012 	dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1013 
1014 	ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1015 	if (ret)
1016 		goto err_alloc_rx_sg;
1017 
1018 	ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1019 	if (ret)
1020 		goto err_alloc_tx_sg;
1021 
1022 	/* Fill in the scatterlists for the RX+TX buffers */
1023 	setup_dma_scatter(pl022, pl022->rx,
1024 			  pl022->cur_transfer->len, &pl022->sgt_rx);
1025 	setup_dma_scatter(pl022, pl022->tx,
1026 			  pl022->cur_transfer->len, &pl022->sgt_tx);
1027 
1028 	/* Map DMA buffers */
1029 	rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1030 			   pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1031 	if (!rx_sglen)
1032 		goto err_rx_sgmap;
1033 
1034 	tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1035 			   pl022->sgt_tx.nents, DMA_TO_DEVICE);
1036 	if (!tx_sglen)
1037 		goto err_tx_sgmap;
1038 
1039 	/* Send both scatterlists */
1040 	rxdesc = dmaengine_prep_slave_sg(rxchan,
1041 				      pl022->sgt_rx.sgl,
1042 				      rx_sglen,
1043 				      DMA_DEV_TO_MEM,
1044 				      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1045 	if (!rxdesc)
1046 		goto err_rxdesc;
1047 
1048 	txdesc = dmaengine_prep_slave_sg(txchan,
1049 				      pl022->sgt_tx.sgl,
1050 				      tx_sglen,
1051 				      DMA_MEM_TO_DEV,
1052 				      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1053 	if (!txdesc)
1054 		goto err_txdesc;
1055 
1056 	/* Put the callback on the RX transfer only, that should finish last */
1057 	rxdesc->callback = dma_callback;
1058 	rxdesc->callback_param = pl022;
1059 
1060 	/* Submit and fire RX and TX with TX last so we're ready to read! */
1061 	dmaengine_submit(rxdesc);
1062 	dmaengine_submit(txdesc);
1063 	dma_async_issue_pending(rxchan);
1064 	dma_async_issue_pending(txchan);
1065 	pl022->dma_running = true;
1066 
1067 	return 0;
1068 
1069 err_txdesc:
1070 	dmaengine_terminate_all(txchan);
1071 err_rxdesc:
1072 	dmaengine_terminate_all(rxchan);
1073 	dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1074 		     pl022->sgt_tx.nents, DMA_TO_DEVICE);
1075 err_tx_sgmap:
1076 	dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1077 		     pl022->sgt_tx.nents, DMA_FROM_DEVICE);
1078 err_rx_sgmap:
1079 	sg_free_table(&pl022->sgt_tx);
1080 err_alloc_tx_sg:
1081 	sg_free_table(&pl022->sgt_rx);
1082 err_alloc_rx_sg:
1083 	return -ENOMEM;
1084 }
1085 
1086 static int pl022_dma_probe(struct pl022 *pl022)
1087 {
1088 	dma_cap_mask_t mask;
1089 
1090 	/* Try to acquire a generic DMA engine slave channel */
1091 	dma_cap_zero(mask);
1092 	dma_cap_set(DMA_SLAVE, mask);
1093 	/*
1094 	 * We need both RX and TX channels to do DMA, else do none
1095 	 * of them.
1096 	 */
1097 	pl022->dma_rx_channel = dma_request_channel(mask,
1098 					    pl022->master_info->dma_filter,
1099 					    pl022->master_info->dma_rx_param);
1100 	if (!pl022->dma_rx_channel) {
1101 		dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1102 		goto err_no_rxchan;
1103 	}
1104 
1105 	pl022->dma_tx_channel = dma_request_channel(mask,
1106 					    pl022->master_info->dma_filter,
1107 					    pl022->master_info->dma_tx_param);
1108 	if (!pl022->dma_tx_channel) {
1109 		dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1110 		goto err_no_txchan;
1111 	}
1112 
1113 	pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1114 	if (!pl022->dummypage) {
1115 		dev_dbg(&pl022->adev->dev, "no DMA dummypage!\n");
1116 		goto err_no_dummypage;
1117 	}
1118 
1119 	dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1120 		 dma_chan_name(pl022->dma_rx_channel),
1121 		 dma_chan_name(pl022->dma_tx_channel));
1122 
1123 	return 0;
1124 
1125 err_no_dummypage:
1126 	dma_release_channel(pl022->dma_tx_channel);
1127 err_no_txchan:
1128 	dma_release_channel(pl022->dma_rx_channel);
1129 	pl022->dma_rx_channel = NULL;
1130 err_no_rxchan:
1131 	dev_err(&pl022->adev->dev,
1132 			"Failed to work in dma mode, work without dma!\n");
1133 	return -ENODEV;
1134 }
1135 
1136 static int pl022_dma_autoprobe(struct pl022 *pl022)
1137 {
1138 	struct device *dev = &pl022->adev->dev;
1139 
1140 	/* automatically configure DMA channels from platform, normally using DT */
1141 	pl022->dma_rx_channel = dma_request_slave_channel(dev, "rx");
1142 	if (!pl022->dma_rx_channel)
1143 		goto err_no_rxchan;
1144 
1145 	pl022->dma_tx_channel = dma_request_slave_channel(dev, "tx");
1146 	if (!pl022->dma_tx_channel)
1147 		goto err_no_txchan;
1148 
1149 	pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1150 	if (!pl022->dummypage)
1151 		goto err_no_dummypage;
1152 
1153 	return 0;
1154 
1155 err_no_dummypage:
1156 	dma_release_channel(pl022->dma_tx_channel);
1157 	pl022->dma_tx_channel = NULL;
1158 err_no_txchan:
1159 	dma_release_channel(pl022->dma_rx_channel);
1160 	pl022->dma_rx_channel = NULL;
1161 err_no_rxchan:
1162 	return -ENODEV;
1163 }
1164 
1165 static void terminate_dma(struct pl022 *pl022)
1166 {
1167 	struct dma_chan *rxchan = pl022->dma_rx_channel;
1168 	struct dma_chan *txchan = pl022->dma_tx_channel;
1169 
1170 	dmaengine_terminate_all(rxchan);
1171 	dmaengine_terminate_all(txchan);
1172 	unmap_free_dma_scatter(pl022);
1173 	pl022->dma_running = false;
1174 }
1175 
1176 static void pl022_dma_remove(struct pl022 *pl022)
1177 {
1178 	if (pl022->dma_running)
1179 		terminate_dma(pl022);
1180 	if (pl022->dma_tx_channel)
1181 		dma_release_channel(pl022->dma_tx_channel);
1182 	if (pl022->dma_rx_channel)
1183 		dma_release_channel(pl022->dma_rx_channel);
1184 	kfree(pl022->dummypage);
1185 }
1186 
1187 #else
1188 static inline int configure_dma(struct pl022 *pl022)
1189 {
1190 	return -ENODEV;
1191 }
1192 
1193 static inline int pl022_dma_autoprobe(struct pl022 *pl022)
1194 {
1195 	return 0;
1196 }
1197 
1198 static inline int pl022_dma_probe(struct pl022 *pl022)
1199 {
1200 	return 0;
1201 }
1202 
1203 static inline void pl022_dma_remove(struct pl022 *pl022)
1204 {
1205 }
1206 #endif
1207 
1208 /**
1209  * pl022_interrupt_handler - Interrupt handler for SSP controller
1210  *
1211  * This function handles interrupts generated for an interrupt based transfer.
1212  * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1213  * current message's state as STATE_ERROR and schedule the tasklet
1214  * pump_transfers which will do the postprocessing of the current message by
1215  * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1216  * more data, and writes data in TX FIFO till it is not full. If we complete
1217  * the transfer we move to the next transfer and schedule the tasklet.
1218  */
1219 static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1220 {
1221 	struct pl022 *pl022 = dev_id;
1222 	struct spi_message *msg = pl022->cur_msg;
1223 	u16 irq_status = 0;
1224 	u16 flag = 0;
1225 
1226 	if (unlikely(!msg)) {
1227 		dev_err(&pl022->adev->dev,
1228 			"bad message state in interrupt handler");
1229 		/* Never fail */
1230 		return IRQ_HANDLED;
1231 	}
1232 
1233 	/* Read the Interrupt Status Register */
1234 	irq_status = readw(SSP_MIS(pl022->virtbase));
1235 
1236 	if (unlikely(!irq_status))
1237 		return IRQ_NONE;
1238 
1239 	/*
1240 	 * This handles the FIFO interrupts, the timeout
1241 	 * interrupts are flatly ignored, they cannot be
1242 	 * trusted.
1243 	 */
1244 	if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1245 		/*
1246 		 * Overrun interrupt - bail out since our Data has been
1247 		 * corrupted
1248 		 */
1249 		dev_err(&pl022->adev->dev, "FIFO overrun\n");
1250 		if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1251 			dev_err(&pl022->adev->dev,
1252 				"RXFIFO is full\n");
1253 		if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
1254 			dev_err(&pl022->adev->dev,
1255 				"TXFIFO is full\n");
1256 
1257 		/*
1258 		 * Disable and clear interrupts, disable SSP,
1259 		 * mark message with bad status so it can be
1260 		 * retried.
1261 		 */
1262 		writew(DISABLE_ALL_INTERRUPTS,
1263 		       SSP_IMSC(pl022->virtbase));
1264 		writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1265 		writew((readw(SSP_CR1(pl022->virtbase)) &
1266 			(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1267 		msg->state = STATE_ERROR;
1268 
1269 		/* Schedule message queue handler */
1270 		tasklet_schedule(&pl022->pump_transfers);
1271 		return IRQ_HANDLED;
1272 	}
1273 
1274 	readwriter(pl022);
1275 
1276 	if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
1277 		flag = 1;
1278 		/* Disable Transmit interrupt, enable receive interrupt */
1279 		writew((readw(SSP_IMSC(pl022->virtbase)) &
1280 		       ~SSP_IMSC_MASK_TXIM) | SSP_IMSC_MASK_RXIM,
1281 		       SSP_IMSC(pl022->virtbase));
1282 	}
1283 
1284 	/*
1285 	 * Since all transactions must write as much as shall be read,
1286 	 * we can conclude the entire transaction once RX is complete.
1287 	 * At this point, all TX will always be finished.
1288 	 */
1289 	if (pl022->rx >= pl022->rx_end) {
1290 		writew(DISABLE_ALL_INTERRUPTS,
1291 		       SSP_IMSC(pl022->virtbase));
1292 		writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1293 		if (unlikely(pl022->rx > pl022->rx_end)) {
1294 			dev_warn(&pl022->adev->dev, "read %u surplus "
1295 				 "bytes (did you request an odd "
1296 				 "number of bytes on a 16bit bus?)\n",
1297 				 (u32) (pl022->rx - pl022->rx_end));
1298 		}
1299 		/* Update total bytes transferred */
1300 		msg->actual_length += pl022->cur_transfer->len;
1301 		if (pl022->cur_transfer->cs_change)
1302 			pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1303 		/* Move to next transfer */
1304 		msg->state = next_transfer(pl022);
1305 		tasklet_schedule(&pl022->pump_transfers);
1306 		return IRQ_HANDLED;
1307 	}
1308 
1309 	return IRQ_HANDLED;
1310 }
1311 
1312 /**
1313  * This sets up the pointers to memory for the next message to
1314  * send out on the SPI bus.
1315  */
1316 static int set_up_next_transfer(struct pl022 *pl022,
1317 				struct spi_transfer *transfer)
1318 {
1319 	int residue;
1320 
1321 	/* Sanity check the message for this bus width */
1322 	residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1323 	if (unlikely(residue != 0)) {
1324 		dev_err(&pl022->adev->dev,
1325 			"message of %u bytes to transmit but the current "
1326 			"chip bus has a data width of %u bytes!\n",
1327 			pl022->cur_transfer->len,
1328 			pl022->cur_chip->n_bytes);
1329 		dev_err(&pl022->adev->dev, "skipping this message\n");
1330 		return -EIO;
1331 	}
1332 	pl022->tx = (void *)transfer->tx_buf;
1333 	pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1334 	pl022->rx = (void *)transfer->rx_buf;
1335 	pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1336 	pl022->write =
1337 	    pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1338 	pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1339 	return 0;
1340 }
1341 
1342 /**
1343  * pump_transfers - Tasklet function which schedules next transfer
1344  * when running in interrupt or DMA transfer mode.
1345  * @data: SSP driver private data structure
1346  *
1347  */
1348 static void pump_transfers(unsigned long data)
1349 {
1350 	struct pl022 *pl022 = (struct pl022 *) data;
1351 	struct spi_message *message = NULL;
1352 	struct spi_transfer *transfer = NULL;
1353 	struct spi_transfer *previous = NULL;
1354 
1355 	/* Get current state information */
1356 	message = pl022->cur_msg;
1357 	transfer = pl022->cur_transfer;
1358 
1359 	/* Handle for abort */
1360 	if (message->state == STATE_ERROR) {
1361 		message->status = -EIO;
1362 		giveback(pl022);
1363 		return;
1364 	}
1365 
1366 	/* Handle end of message */
1367 	if (message->state == STATE_DONE) {
1368 		message->status = 0;
1369 		giveback(pl022);
1370 		return;
1371 	}
1372 
1373 	/* Delay if requested at end of transfer before CS change */
1374 	if (message->state == STATE_RUNNING) {
1375 		previous = list_entry(transfer->transfer_list.prev,
1376 					struct spi_transfer,
1377 					transfer_list);
1378 		if (previous->delay_usecs)
1379 			/*
1380 			 * FIXME: This runs in interrupt context.
1381 			 * Is this really smart?
1382 			 */
1383 			udelay(previous->delay_usecs);
1384 
1385 		/* Reselect chip select only if cs_change was requested */
1386 		if (previous->cs_change)
1387 			pl022_cs_control(pl022, SSP_CHIP_SELECT);
1388 	} else {
1389 		/* STATE_START */
1390 		message->state = STATE_RUNNING;
1391 	}
1392 
1393 	if (set_up_next_transfer(pl022, transfer)) {
1394 		message->state = STATE_ERROR;
1395 		message->status = -EIO;
1396 		giveback(pl022);
1397 		return;
1398 	}
1399 	/* Flush the FIFOs and let's go! */
1400 	flush(pl022);
1401 
1402 	if (pl022->cur_chip->enable_dma) {
1403 		if (configure_dma(pl022)) {
1404 			dev_dbg(&pl022->adev->dev,
1405 				"configuration of DMA failed, fall back to interrupt mode\n");
1406 			goto err_config_dma;
1407 		}
1408 		return;
1409 	}
1410 
1411 err_config_dma:
1412 	/* enable all interrupts except RX */
1413 	writew(ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM, SSP_IMSC(pl022->virtbase));
1414 }
1415 
1416 static void do_interrupt_dma_transfer(struct pl022 *pl022)
1417 {
1418 	/*
1419 	 * Default is to enable all interrupts except RX -
1420 	 * this will be enabled once TX is complete
1421 	 */
1422 	u32 irqflags = ENABLE_ALL_INTERRUPTS & ~SSP_IMSC_MASK_RXIM;
1423 
1424 	/* Enable target chip, if not already active */
1425 	if (!pl022->next_msg_cs_active)
1426 		pl022_cs_control(pl022, SSP_CHIP_SELECT);
1427 
1428 	if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1429 		/* Error path */
1430 		pl022->cur_msg->state = STATE_ERROR;
1431 		pl022->cur_msg->status = -EIO;
1432 		giveback(pl022);
1433 		return;
1434 	}
1435 	/* If we're using DMA, set up DMA here */
1436 	if (pl022->cur_chip->enable_dma) {
1437 		/* Configure DMA transfer */
1438 		if (configure_dma(pl022)) {
1439 			dev_dbg(&pl022->adev->dev,
1440 				"configuration of DMA failed, fall back to interrupt mode\n");
1441 			goto err_config_dma;
1442 		}
1443 		/* Disable interrupts in DMA mode, IRQ from DMA controller */
1444 		irqflags = DISABLE_ALL_INTERRUPTS;
1445 	}
1446 err_config_dma:
1447 	/* Enable SSP, turn on interrupts */
1448 	writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1449 	       SSP_CR1(pl022->virtbase));
1450 	writew(irqflags, SSP_IMSC(pl022->virtbase));
1451 }
1452 
1453 static void do_polling_transfer(struct pl022 *pl022)
1454 {
1455 	struct spi_message *message = NULL;
1456 	struct spi_transfer *transfer = NULL;
1457 	struct spi_transfer *previous = NULL;
1458 	struct chip_data *chip;
1459 	unsigned long time, timeout;
1460 
1461 	chip = pl022->cur_chip;
1462 	message = pl022->cur_msg;
1463 
1464 	while (message->state != STATE_DONE) {
1465 		/* Handle for abort */
1466 		if (message->state == STATE_ERROR)
1467 			break;
1468 		transfer = pl022->cur_transfer;
1469 
1470 		/* Delay if requested at end of transfer */
1471 		if (message->state == STATE_RUNNING) {
1472 			previous =
1473 			    list_entry(transfer->transfer_list.prev,
1474 				       struct spi_transfer, transfer_list);
1475 			if (previous->delay_usecs)
1476 				udelay(previous->delay_usecs);
1477 			if (previous->cs_change)
1478 				pl022_cs_control(pl022, SSP_CHIP_SELECT);
1479 		} else {
1480 			/* STATE_START */
1481 			message->state = STATE_RUNNING;
1482 			if (!pl022->next_msg_cs_active)
1483 				pl022_cs_control(pl022, SSP_CHIP_SELECT);
1484 		}
1485 
1486 		/* Configuration Changing Per Transfer */
1487 		if (set_up_next_transfer(pl022, transfer)) {
1488 			/* Error path */
1489 			message->state = STATE_ERROR;
1490 			break;
1491 		}
1492 		/* Flush FIFOs and enable SSP */
1493 		flush(pl022);
1494 		writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1495 		       SSP_CR1(pl022->virtbase));
1496 
1497 		dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1498 
1499 		timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1500 		while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1501 			time = jiffies;
1502 			readwriter(pl022);
1503 			if (time_after(time, timeout)) {
1504 				dev_warn(&pl022->adev->dev,
1505 				"%s: timeout!\n", __func__);
1506 				message->state = STATE_ERROR;
1507 				goto out;
1508 			}
1509 			cpu_relax();
1510 		}
1511 
1512 		/* Update total byte transferred */
1513 		message->actual_length += pl022->cur_transfer->len;
1514 		if (pl022->cur_transfer->cs_change)
1515 			pl022_cs_control(pl022, SSP_CHIP_DESELECT);
1516 		/* Move to next transfer */
1517 		message->state = next_transfer(pl022);
1518 	}
1519 out:
1520 	/* Handle end of message */
1521 	if (message->state == STATE_DONE)
1522 		message->status = 0;
1523 	else
1524 		message->status = -EIO;
1525 
1526 	giveback(pl022);
1527 	return;
1528 }
1529 
1530 static int pl022_transfer_one_message(struct spi_master *master,
1531 				      struct spi_message *msg)
1532 {
1533 	struct pl022 *pl022 = spi_master_get_devdata(master);
1534 
1535 	/* Initial message state */
1536 	pl022->cur_msg = msg;
1537 	msg->state = STATE_START;
1538 
1539 	pl022->cur_transfer = list_entry(msg->transfers.next,
1540 					 struct spi_transfer, transfer_list);
1541 
1542 	/* Setup the SPI using the per chip configuration */
1543 	pl022->cur_chip = spi_get_ctldata(msg->spi);
1544 	pl022->cur_cs = pl022->chipselects[msg->spi->chip_select];
1545 
1546 	restore_state(pl022);
1547 	flush(pl022);
1548 
1549 	if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1550 		do_polling_transfer(pl022);
1551 	else
1552 		do_interrupt_dma_transfer(pl022);
1553 
1554 	return 0;
1555 }
1556 
1557 static int pl022_unprepare_transfer_hardware(struct spi_master *master)
1558 {
1559 	struct pl022 *pl022 = spi_master_get_devdata(master);
1560 
1561 	/* nothing more to do - disable spi/ssp and power off */
1562 	writew((readw(SSP_CR1(pl022->virtbase)) &
1563 		(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1564 
1565 	return 0;
1566 }
1567 
1568 static int verify_controller_parameters(struct pl022 *pl022,
1569 				struct pl022_config_chip const *chip_info)
1570 {
1571 	if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1572 	    || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1573 		dev_err(&pl022->adev->dev,
1574 			"interface is configured incorrectly\n");
1575 		return -EINVAL;
1576 	}
1577 	if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1578 	    (!pl022->vendor->unidir)) {
1579 		dev_err(&pl022->adev->dev,
1580 			"unidirectional mode not supported in this "
1581 			"hardware version\n");
1582 		return -EINVAL;
1583 	}
1584 	if ((chip_info->hierarchy != SSP_MASTER)
1585 	    && (chip_info->hierarchy != SSP_SLAVE)) {
1586 		dev_err(&pl022->adev->dev,
1587 			"hierarchy is configured incorrectly\n");
1588 		return -EINVAL;
1589 	}
1590 	if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1591 	    && (chip_info->com_mode != DMA_TRANSFER)
1592 	    && (chip_info->com_mode != POLLING_TRANSFER)) {
1593 		dev_err(&pl022->adev->dev,
1594 			"Communication mode is configured incorrectly\n");
1595 		return -EINVAL;
1596 	}
1597 	switch (chip_info->rx_lev_trig) {
1598 	case SSP_RX_1_OR_MORE_ELEM:
1599 	case SSP_RX_4_OR_MORE_ELEM:
1600 	case SSP_RX_8_OR_MORE_ELEM:
1601 		/* These are always OK, all variants can handle this */
1602 		break;
1603 	case SSP_RX_16_OR_MORE_ELEM:
1604 		if (pl022->vendor->fifodepth < 16) {
1605 			dev_err(&pl022->adev->dev,
1606 			"RX FIFO Trigger Level is configured incorrectly\n");
1607 			return -EINVAL;
1608 		}
1609 		break;
1610 	case SSP_RX_32_OR_MORE_ELEM:
1611 		if (pl022->vendor->fifodepth < 32) {
1612 			dev_err(&pl022->adev->dev,
1613 			"RX FIFO Trigger Level is configured incorrectly\n");
1614 			return -EINVAL;
1615 		}
1616 		break;
1617 	default:
1618 		dev_err(&pl022->adev->dev,
1619 			"RX FIFO Trigger Level is configured incorrectly\n");
1620 		return -EINVAL;
1621 	}
1622 	switch (chip_info->tx_lev_trig) {
1623 	case SSP_TX_1_OR_MORE_EMPTY_LOC:
1624 	case SSP_TX_4_OR_MORE_EMPTY_LOC:
1625 	case SSP_TX_8_OR_MORE_EMPTY_LOC:
1626 		/* These are always OK, all variants can handle this */
1627 		break;
1628 	case SSP_TX_16_OR_MORE_EMPTY_LOC:
1629 		if (pl022->vendor->fifodepth < 16) {
1630 			dev_err(&pl022->adev->dev,
1631 			"TX FIFO Trigger Level is configured incorrectly\n");
1632 			return -EINVAL;
1633 		}
1634 		break;
1635 	case SSP_TX_32_OR_MORE_EMPTY_LOC:
1636 		if (pl022->vendor->fifodepth < 32) {
1637 			dev_err(&pl022->adev->dev,
1638 			"TX FIFO Trigger Level is configured incorrectly\n");
1639 			return -EINVAL;
1640 		}
1641 		break;
1642 	default:
1643 		dev_err(&pl022->adev->dev,
1644 			"TX FIFO Trigger Level is configured incorrectly\n");
1645 		return -EINVAL;
1646 	}
1647 	if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1648 		if ((chip_info->ctrl_len < SSP_BITS_4)
1649 		    || (chip_info->ctrl_len > SSP_BITS_32)) {
1650 			dev_err(&pl022->adev->dev,
1651 				"CTRL LEN is configured incorrectly\n");
1652 			return -EINVAL;
1653 		}
1654 		if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1655 		    && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1656 			dev_err(&pl022->adev->dev,
1657 				"Wait State is configured incorrectly\n");
1658 			return -EINVAL;
1659 		}
1660 		/* Half duplex is only available in the ST Micro version */
1661 		if (pl022->vendor->extended_cr) {
1662 			if ((chip_info->duplex !=
1663 			     SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1664 			    && (chip_info->duplex !=
1665 				SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1666 				dev_err(&pl022->adev->dev,
1667 					"Microwire duplex mode is configured incorrectly\n");
1668 				return -EINVAL;
1669 			}
1670 		} else {
1671 			if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1672 				dev_err(&pl022->adev->dev,
1673 					"Microwire half duplex mode requested,"
1674 					" but this is only available in the"
1675 					" ST version of PL022\n");
1676 			return -EINVAL;
1677 		}
1678 	}
1679 	return 0;
1680 }
1681 
1682 static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1683 {
1684 	return rate / (cpsdvsr * (1 + scr));
1685 }
1686 
1687 static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1688 				    ssp_clock_params * clk_freq)
1689 {
1690 	/* Lets calculate the frequency parameters */
1691 	u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1692 	u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1693 		best_scr = 0, tmp, found = 0;
1694 
1695 	rate = clk_get_rate(pl022->clk);
1696 	/* cpsdvscr = 2 & scr 0 */
1697 	max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1698 	/* cpsdvsr = 254 & scr = 255 */
1699 	min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1700 
1701 	if (freq > max_tclk)
1702 		dev_warn(&pl022->adev->dev,
1703 			"Max speed that can be programmed is %d Hz, you requested %d\n",
1704 			max_tclk, freq);
1705 
1706 	if (freq < min_tclk) {
1707 		dev_err(&pl022->adev->dev,
1708 			"Requested frequency: %d Hz is less than minimum possible %d Hz\n",
1709 			freq, min_tclk);
1710 		return -EINVAL;
1711 	}
1712 
1713 	/*
1714 	 * best_freq will give closest possible available rate (<= requested
1715 	 * freq) for all values of scr & cpsdvsr.
1716 	 */
1717 	while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1718 		while (scr <= SCR_MAX) {
1719 			tmp = spi_rate(rate, cpsdvsr, scr);
1720 
1721 			if (tmp > freq) {
1722 				/* we need lower freq */
1723 				scr++;
1724 				continue;
1725 			}
1726 
1727 			/*
1728 			 * If found exact value, mark found and break.
1729 			 * If found more closer value, update and break.
1730 			 */
1731 			if (tmp > best_freq) {
1732 				best_freq = tmp;
1733 				best_cpsdvsr = cpsdvsr;
1734 				best_scr = scr;
1735 
1736 				if (tmp == freq)
1737 					found = 1;
1738 			}
1739 			/*
1740 			 * increased scr will give lower rates, which are not
1741 			 * required
1742 			 */
1743 			break;
1744 		}
1745 		cpsdvsr += 2;
1746 		scr = SCR_MIN;
1747 	}
1748 
1749 	WARN(!best_freq, "pl022: Matching cpsdvsr and scr not found for %d Hz rate \n",
1750 			freq);
1751 
1752 	clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1753 	clk_freq->scr = (u8) (best_scr & 0xFF);
1754 	dev_dbg(&pl022->adev->dev,
1755 		"SSP Target Frequency is: %u, Effective Frequency is %u\n",
1756 		freq, best_freq);
1757 	dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1758 		clk_freq->cpsdvsr, clk_freq->scr);
1759 
1760 	return 0;
1761 }
1762 
1763 /*
1764  * A piece of default chip info unless the platform
1765  * supplies it.
1766  */
1767 static const struct pl022_config_chip pl022_default_chip_info = {
1768 	.com_mode = POLLING_TRANSFER,
1769 	.iface = SSP_INTERFACE_MOTOROLA_SPI,
1770 	.hierarchy = SSP_SLAVE,
1771 	.slave_tx_disable = DO_NOT_DRIVE_TX,
1772 	.rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1773 	.tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1774 	.ctrl_len = SSP_BITS_8,
1775 	.wait_state = SSP_MWIRE_WAIT_ZERO,
1776 	.duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1777 	.cs_control = null_cs_control,
1778 };
1779 
1780 /**
1781  * pl022_setup - setup function registered to SPI master framework
1782  * @spi: spi device which is requesting setup
1783  *
1784  * This function is registered to the SPI framework for this SPI master
1785  * controller. If it is the first time when setup is called by this device,
1786  * this function will initialize the runtime state for this chip and save
1787  * the same in the device structure. Else it will update the runtime info
1788  * with the updated chip info. Nothing is really being written to the
1789  * controller hardware here, that is not done until the actual transfer
1790  * commence.
1791  */
1792 static int pl022_setup(struct spi_device *spi)
1793 {
1794 	struct pl022_config_chip const *chip_info;
1795 	struct pl022_config_chip chip_info_dt;
1796 	struct chip_data *chip;
1797 	struct ssp_clock_params clk_freq = { .cpsdvsr = 0, .scr = 0};
1798 	int status = 0;
1799 	struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1800 	unsigned int bits = spi->bits_per_word;
1801 	u32 tmp;
1802 	struct device_node *np = spi->dev.of_node;
1803 
1804 	if (!spi->max_speed_hz)
1805 		return -EINVAL;
1806 
1807 	/* Get controller_state if one is supplied */
1808 	chip = spi_get_ctldata(spi);
1809 
1810 	if (chip == NULL) {
1811 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1812 		if (!chip) {
1813 			dev_err(&spi->dev,
1814 				"cannot allocate controller state\n");
1815 			return -ENOMEM;
1816 		}
1817 		dev_dbg(&spi->dev,
1818 			"allocated memory for controller's runtime state\n");
1819 	}
1820 
1821 	/* Get controller data if one is supplied */
1822 	chip_info = spi->controller_data;
1823 
1824 	if (chip_info == NULL) {
1825 		if (np) {
1826 			chip_info_dt = pl022_default_chip_info;
1827 
1828 			chip_info_dt.hierarchy = SSP_MASTER;
1829 			of_property_read_u32(np, "pl022,interface",
1830 				&chip_info_dt.iface);
1831 			of_property_read_u32(np, "pl022,com-mode",
1832 				&chip_info_dt.com_mode);
1833 			of_property_read_u32(np, "pl022,rx-level-trig",
1834 				&chip_info_dt.rx_lev_trig);
1835 			of_property_read_u32(np, "pl022,tx-level-trig",
1836 				&chip_info_dt.tx_lev_trig);
1837 			of_property_read_u32(np, "pl022,ctrl-len",
1838 				&chip_info_dt.ctrl_len);
1839 			of_property_read_u32(np, "pl022,wait-state",
1840 				&chip_info_dt.wait_state);
1841 			of_property_read_u32(np, "pl022,duplex",
1842 				&chip_info_dt.duplex);
1843 
1844 			chip_info = &chip_info_dt;
1845 		} else {
1846 			chip_info = &pl022_default_chip_info;
1847 			/* spi_board_info.controller_data not is supplied */
1848 			dev_dbg(&spi->dev,
1849 				"using default controller_data settings\n");
1850 		}
1851 	} else
1852 		dev_dbg(&spi->dev,
1853 			"using user supplied controller_data settings\n");
1854 
1855 	/*
1856 	 * We can override with custom divisors, else we use the board
1857 	 * frequency setting
1858 	 */
1859 	if ((0 == chip_info->clk_freq.cpsdvsr)
1860 	    && (0 == chip_info->clk_freq.scr)) {
1861 		status = calculate_effective_freq(pl022,
1862 						  spi->max_speed_hz,
1863 						  &clk_freq);
1864 		if (status < 0)
1865 			goto err_config_params;
1866 	} else {
1867 		memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1868 		if ((clk_freq.cpsdvsr % 2) != 0)
1869 			clk_freq.cpsdvsr =
1870 				clk_freq.cpsdvsr - 1;
1871 	}
1872 	if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1873 	    || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1874 		status = -EINVAL;
1875 		dev_err(&spi->dev,
1876 			"cpsdvsr is configured incorrectly\n");
1877 		goto err_config_params;
1878 	}
1879 
1880 	status = verify_controller_parameters(pl022, chip_info);
1881 	if (status) {
1882 		dev_err(&spi->dev, "controller data is incorrect");
1883 		goto err_config_params;
1884 	}
1885 
1886 	pl022->rx_lev_trig = chip_info->rx_lev_trig;
1887 	pl022->tx_lev_trig = chip_info->tx_lev_trig;
1888 
1889 	/* Now set controller state based on controller data */
1890 	chip->xfer_type = chip_info->com_mode;
1891 	if (!chip_info->cs_control) {
1892 		chip->cs_control = null_cs_control;
1893 		if (!gpio_is_valid(pl022->chipselects[spi->chip_select]))
1894 			dev_warn(&spi->dev,
1895 				 "invalid chip select\n");
1896 	} else
1897 		chip->cs_control = chip_info->cs_control;
1898 
1899 	/* Check bits per word with vendor specific range */
1900 	if ((bits <= 3) || (bits > pl022->vendor->max_bpw)) {
1901 		status = -ENOTSUPP;
1902 		dev_err(&spi->dev, "illegal data size for this controller!\n");
1903 		dev_err(&spi->dev, "This controller can only handle 4 <= n <= %d bit words\n",
1904 				pl022->vendor->max_bpw);
1905 		goto err_config_params;
1906 	} else if (bits <= 8) {
1907 		dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1908 		chip->n_bytes = 1;
1909 		chip->read = READING_U8;
1910 		chip->write = WRITING_U8;
1911 	} else if (bits <= 16) {
1912 		dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1913 		chip->n_bytes = 2;
1914 		chip->read = READING_U16;
1915 		chip->write = WRITING_U16;
1916 	} else {
1917 		dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1918 		chip->n_bytes = 4;
1919 		chip->read = READING_U32;
1920 		chip->write = WRITING_U32;
1921 	}
1922 
1923 	/* Now Initialize all register settings required for this chip */
1924 	chip->cr0 = 0;
1925 	chip->cr1 = 0;
1926 	chip->dmacr = 0;
1927 	chip->cpsr = 0;
1928 	if ((chip_info->com_mode == DMA_TRANSFER)
1929 	    && ((pl022->master_info)->enable_dma)) {
1930 		chip->enable_dma = true;
1931 		dev_dbg(&spi->dev, "DMA mode set in controller state\n");
1932 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1933 			       SSP_DMACR_MASK_RXDMAE, 0);
1934 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
1935 			       SSP_DMACR_MASK_TXDMAE, 1);
1936 	} else {
1937 		chip->enable_dma = false;
1938 		dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
1939 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1940 			       SSP_DMACR_MASK_RXDMAE, 0);
1941 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
1942 			       SSP_DMACR_MASK_TXDMAE, 1);
1943 	}
1944 
1945 	chip->cpsr = clk_freq.cpsdvsr;
1946 
1947 	/* Special setup for the ST micro extended control registers */
1948 	if (pl022->vendor->extended_cr) {
1949 		u32 etx;
1950 
1951 		if (pl022->vendor->pl023) {
1952 			/* These bits are only in the PL023 */
1953 			SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
1954 				       SSP_CR1_MASK_FBCLKDEL_ST, 13);
1955 		} else {
1956 			/* These bits are in the PL022 but not PL023 */
1957 			SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
1958 				       SSP_CR0_MASK_HALFDUP_ST, 5);
1959 			SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
1960 				       SSP_CR0_MASK_CSS_ST, 16);
1961 			SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1962 				       SSP_CR0_MASK_FRF_ST, 21);
1963 			SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
1964 				       SSP_CR1_MASK_MWAIT_ST, 6);
1965 		}
1966 		SSP_WRITE_BITS(chip->cr0, bits - 1,
1967 			       SSP_CR0_MASK_DSS_ST, 0);
1968 
1969 		if (spi->mode & SPI_LSB_FIRST) {
1970 			tmp = SSP_RX_LSB;
1971 			etx = SSP_TX_LSB;
1972 		} else {
1973 			tmp = SSP_RX_MSB;
1974 			etx = SSP_TX_MSB;
1975 		}
1976 		SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
1977 		SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
1978 		SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
1979 			       SSP_CR1_MASK_RXIFLSEL_ST, 7);
1980 		SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
1981 			       SSP_CR1_MASK_TXIFLSEL_ST, 10);
1982 	} else {
1983 		SSP_WRITE_BITS(chip->cr0, bits - 1,
1984 			       SSP_CR0_MASK_DSS, 0);
1985 		SSP_WRITE_BITS(chip->cr0, chip_info->iface,
1986 			       SSP_CR0_MASK_FRF, 4);
1987 	}
1988 
1989 	/* Stuff that is common for all versions */
1990 	if (spi->mode & SPI_CPOL)
1991 		tmp = SSP_CLK_POL_IDLE_HIGH;
1992 	else
1993 		tmp = SSP_CLK_POL_IDLE_LOW;
1994 	SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
1995 
1996 	if (spi->mode & SPI_CPHA)
1997 		tmp = SSP_CLK_SECOND_EDGE;
1998 	else
1999 		tmp = SSP_CLK_FIRST_EDGE;
2000 	SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2001 
2002 	SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2003 	/* Loopback is available on all versions except PL023 */
2004 	if (pl022->vendor->loopback) {
2005 		if (spi->mode & SPI_LOOP)
2006 			tmp = LOOPBACK_ENABLED;
2007 		else
2008 			tmp = LOOPBACK_DISABLED;
2009 		SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2010 	}
2011 	SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2012 	SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2013 	SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2014 		3);
2015 
2016 	/* Save controller_state */
2017 	spi_set_ctldata(spi, chip);
2018 	return status;
2019  err_config_params:
2020 	spi_set_ctldata(spi, NULL);
2021 	kfree(chip);
2022 	return status;
2023 }
2024 
2025 /**
2026  * pl022_cleanup - cleanup function registered to SPI master framework
2027  * @spi: spi device which is requesting cleanup
2028  *
2029  * This function is registered to the SPI framework for this SPI master
2030  * controller. It will free the runtime state of chip.
2031  */
2032 static void pl022_cleanup(struct spi_device *spi)
2033 {
2034 	struct chip_data *chip = spi_get_ctldata(spi);
2035 
2036 	spi_set_ctldata(spi, NULL);
2037 	kfree(chip);
2038 }
2039 
2040 static struct pl022_ssp_controller *
2041 pl022_platform_data_dt_get(struct device *dev)
2042 {
2043 	struct device_node *np = dev->of_node;
2044 	struct pl022_ssp_controller *pd;
2045 	u32 tmp;
2046 
2047 	if (!np) {
2048 		dev_err(dev, "no dt node defined\n");
2049 		return NULL;
2050 	}
2051 
2052 	pd = devm_kzalloc(dev, sizeof(struct pl022_ssp_controller), GFP_KERNEL);
2053 	if (!pd) {
2054 		dev_err(dev, "cannot allocate platform data memory\n");
2055 		return NULL;
2056 	}
2057 
2058 	pd->bus_id = -1;
2059 	pd->enable_dma = 1;
2060 	of_property_read_u32(np, "num-cs", &tmp);
2061 	pd->num_chipselect = tmp;
2062 	of_property_read_u32(np, "pl022,autosuspend-delay",
2063 			     &pd->autosuspend_delay);
2064 	pd->rt = of_property_read_bool(np, "pl022,rt");
2065 
2066 	return pd;
2067 }
2068 
2069 static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
2070 {
2071 	struct device *dev = &adev->dev;
2072 	struct pl022_ssp_controller *platform_info =
2073 			dev_get_platdata(&adev->dev);
2074 	struct spi_master *master;
2075 	struct pl022 *pl022 = NULL;	/*Data for this driver */
2076 	struct device_node *np = adev->dev.of_node;
2077 	int status = 0, i, num_cs;
2078 
2079 	dev_info(&adev->dev,
2080 		 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2081 	if (!platform_info && IS_ENABLED(CONFIG_OF))
2082 		platform_info = pl022_platform_data_dt_get(dev);
2083 
2084 	if (!platform_info) {
2085 		dev_err(dev, "probe: no platform data defined\n");
2086 		return -ENODEV;
2087 	}
2088 
2089 	if (platform_info->num_chipselect) {
2090 		num_cs = platform_info->num_chipselect;
2091 	} else {
2092 		dev_err(dev, "probe: no chip select defined\n");
2093 		return -ENODEV;
2094 	}
2095 
2096 	/* Allocate master with space for data */
2097 	master = spi_alloc_master(dev, sizeof(struct pl022));
2098 	if (master == NULL) {
2099 		dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2100 		return -ENOMEM;
2101 	}
2102 
2103 	pl022 = spi_master_get_devdata(master);
2104 	pl022->master = master;
2105 	pl022->master_info = platform_info;
2106 	pl022->adev = adev;
2107 	pl022->vendor = id->data;
2108 	pl022->chipselects = devm_kzalloc(dev, num_cs * sizeof(int),
2109 					  GFP_KERNEL);
2110 
2111 	pinctrl_pm_select_default_state(dev);
2112 
2113 	/*
2114 	 * Bus Number Which has been Assigned to this SSP controller
2115 	 * on this board
2116 	 */
2117 	master->bus_num = platform_info->bus_id;
2118 	master->num_chipselect = num_cs;
2119 	master->cleanup = pl022_cleanup;
2120 	master->setup = pl022_setup;
2121 	master->auto_runtime_pm = true;
2122 	master->transfer_one_message = pl022_transfer_one_message;
2123 	master->unprepare_transfer_hardware = pl022_unprepare_transfer_hardware;
2124 	master->rt = platform_info->rt;
2125 	master->dev.of_node = dev->of_node;
2126 
2127 	if (platform_info->num_chipselect && platform_info->chipselects) {
2128 		for (i = 0; i < num_cs; i++)
2129 			pl022->chipselects[i] = platform_info->chipselects[i];
2130 	} else if (IS_ENABLED(CONFIG_OF)) {
2131 		for (i = 0; i < num_cs; i++) {
2132 			int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
2133 
2134 			if (cs_gpio == -EPROBE_DEFER) {
2135 				status = -EPROBE_DEFER;
2136 				goto err_no_gpio;
2137 			}
2138 
2139 			pl022->chipselects[i] = cs_gpio;
2140 
2141 			if (gpio_is_valid(cs_gpio)) {
2142 				if (devm_gpio_request(dev, cs_gpio, "ssp-pl022"))
2143 					dev_err(&adev->dev,
2144 						"could not request %d gpio\n",
2145 						cs_gpio);
2146 				else if (gpio_direction_output(cs_gpio, 1))
2147 					dev_err(&adev->dev,
2148 						"could set gpio %d as output\n",
2149 						cs_gpio);
2150 			}
2151 		}
2152 	}
2153 
2154 	/*
2155 	 * Supports mode 0-3, loopback, and active low CS. Transfers are
2156 	 * always MS bit first on the original pl022.
2157 	 */
2158 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2159 	if (pl022->vendor->extended_cr)
2160 		master->mode_bits |= SPI_LSB_FIRST;
2161 
2162 	dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2163 
2164 	status = amba_request_regions(adev, NULL);
2165 	if (status)
2166 		goto err_no_ioregion;
2167 
2168 	pl022->phybase = adev->res.start;
2169 	pl022->virtbase = devm_ioremap(dev, adev->res.start,
2170 				       resource_size(&adev->res));
2171 	if (pl022->virtbase == NULL) {
2172 		status = -ENOMEM;
2173 		goto err_no_ioremap;
2174 	}
2175 	dev_info(&adev->dev, "mapped registers from %pa to %p\n",
2176 		&adev->res.start, pl022->virtbase);
2177 
2178 	pl022->clk = devm_clk_get(&adev->dev, NULL);
2179 	if (IS_ERR(pl022->clk)) {
2180 		status = PTR_ERR(pl022->clk);
2181 		dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2182 		goto err_no_clk;
2183 	}
2184 
2185 	status = clk_prepare(pl022->clk);
2186 	if (status) {
2187 		dev_err(&adev->dev, "could not prepare SSP/SPI bus clock\n");
2188 		goto  err_clk_prep;
2189 	}
2190 
2191 	status = clk_enable(pl022->clk);
2192 	if (status) {
2193 		dev_err(&adev->dev, "could not enable SSP/SPI bus clock\n");
2194 		goto err_no_clk_en;
2195 	}
2196 
2197 	/* Initialize transfer pump */
2198 	tasklet_init(&pl022->pump_transfers, pump_transfers,
2199 		     (unsigned long)pl022);
2200 
2201 	/* Disable SSP */
2202 	writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2203 	       SSP_CR1(pl022->virtbase));
2204 	load_ssp_default_config(pl022);
2205 
2206 	status = devm_request_irq(dev, adev->irq[0], pl022_interrupt_handler,
2207 				  0, "pl022", pl022);
2208 	if (status < 0) {
2209 		dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2210 		goto err_no_irq;
2211 	}
2212 
2213 	/* Get DMA channels, try autoconfiguration first */
2214 	status = pl022_dma_autoprobe(pl022);
2215 
2216 	/* If that failed, use channels from platform_info */
2217 	if (status == 0)
2218 		platform_info->enable_dma = 1;
2219 	else if (platform_info->enable_dma) {
2220 		status = pl022_dma_probe(pl022);
2221 		if (status != 0)
2222 			platform_info->enable_dma = 0;
2223 	}
2224 
2225 	/* Register with the SPI framework */
2226 	amba_set_drvdata(adev, pl022);
2227 	status = devm_spi_register_master(&adev->dev, master);
2228 	if (status != 0) {
2229 		dev_err(&adev->dev,
2230 			"probe - problem registering spi master\n");
2231 		goto err_spi_register;
2232 	}
2233 	dev_dbg(dev, "probe succeeded\n");
2234 
2235 	/* let runtime pm put suspend */
2236 	if (platform_info->autosuspend_delay > 0) {
2237 		dev_info(&adev->dev,
2238 			"will use autosuspend for runtime pm, delay %dms\n",
2239 			platform_info->autosuspend_delay);
2240 		pm_runtime_set_autosuspend_delay(dev,
2241 			platform_info->autosuspend_delay);
2242 		pm_runtime_use_autosuspend(dev);
2243 	}
2244 	pm_runtime_put(dev);
2245 
2246 	return 0;
2247 
2248  err_spi_register:
2249 	if (platform_info->enable_dma)
2250 		pl022_dma_remove(pl022);
2251  err_no_irq:
2252 	clk_disable(pl022->clk);
2253  err_no_clk_en:
2254 	clk_unprepare(pl022->clk);
2255  err_clk_prep:
2256  err_no_clk:
2257  err_no_ioremap:
2258 	amba_release_regions(adev);
2259  err_no_ioregion:
2260  err_no_gpio:
2261 	spi_master_put(master);
2262 	return status;
2263 }
2264 
2265 static int
2266 pl022_remove(struct amba_device *adev)
2267 {
2268 	struct pl022 *pl022 = amba_get_drvdata(adev);
2269 
2270 	if (!pl022)
2271 		return 0;
2272 
2273 	/*
2274 	 * undo pm_runtime_put() in probe.  I assume that we're not
2275 	 * accessing the primecell here.
2276 	 */
2277 	pm_runtime_get_noresume(&adev->dev);
2278 
2279 	load_ssp_default_config(pl022);
2280 	if (pl022->master_info->enable_dma)
2281 		pl022_dma_remove(pl022);
2282 
2283 	clk_disable(pl022->clk);
2284 	clk_unprepare(pl022->clk);
2285 	amba_release_regions(adev);
2286 	tasklet_disable(&pl022->pump_transfers);
2287 	return 0;
2288 }
2289 
2290 #if defined(CONFIG_SUSPEND) || defined(CONFIG_PM_RUNTIME)
2291 /*
2292  * These two functions are used from both suspend/resume and
2293  * the runtime counterparts to handle external resources like
2294  * clocks, pins and regulators when going to sleep.
2295  */
2296 static void pl022_suspend_resources(struct pl022 *pl022, bool runtime)
2297 {
2298 	clk_disable(pl022->clk);
2299 
2300 	if (runtime)
2301 		pinctrl_pm_select_idle_state(&pl022->adev->dev);
2302 	else
2303 		pinctrl_pm_select_sleep_state(&pl022->adev->dev);
2304 }
2305 
2306 static void pl022_resume_resources(struct pl022 *pl022, bool runtime)
2307 {
2308 	/* First go to the default state */
2309 	pinctrl_pm_select_default_state(&pl022->adev->dev);
2310 	if (!runtime)
2311 		/* Then let's idle the pins until the next transfer happens */
2312 		pinctrl_pm_select_idle_state(&pl022->adev->dev);
2313 
2314 	clk_enable(pl022->clk);
2315 }
2316 #endif
2317 
2318 #ifdef CONFIG_SUSPEND
2319 static int pl022_suspend(struct device *dev)
2320 {
2321 	struct pl022 *pl022 = dev_get_drvdata(dev);
2322 	int ret;
2323 
2324 	ret = spi_master_suspend(pl022->master);
2325 	if (ret) {
2326 		dev_warn(dev, "cannot suspend master\n");
2327 		return ret;
2328 	}
2329 
2330 	pm_runtime_get_sync(dev);
2331 	pl022_suspend_resources(pl022, false);
2332 
2333 	dev_dbg(dev, "suspended\n");
2334 	return 0;
2335 }
2336 
2337 static int pl022_resume(struct device *dev)
2338 {
2339 	struct pl022 *pl022 = dev_get_drvdata(dev);
2340 	int ret;
2341 
2342 	pl022_resume_resources(pl022, false);
2343 	pm_runtime_put(dev);
2344 
2345 	/* Start the queue running */
2346 	ret = spi_master_resume(pl022->master);
2347 	if (ret)
2348 		dev_err(dev, "problem starting queue (%d)\n", ret);
2349 	else
2350 		dev_dbg(dev, "resumed\n");
2351 
2352 	return ret;
2353 }
2354 #endif	/* CONFIG_PM */
2355 
2356 #ifdef CONFIG_PM_RUNTIME
2357 static int pl022_runtime_suspend(struct device *dev)
2358 {
2359 	struct pl022 *pl022 = dev_get_drvdata(dev);
2360 
2361 	pl022_suspend_resources(pl022, true);
2362 	return 0;
2363 }
2364 
2365 static int pl022_runtime_resume(struct device *dev)
2366 {
2367 	struct pl022 *pl022 = dev_get_drvdata(dev);
2368 
2369 	pl022_resume_resources(pl022, true);
2370 	return 0;
2371 }
2372 #endif
2373 
2374 static const struct dev_pm_ops pl022_dev_pm_ops = {
2375 	SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2376 	SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2377 };
2378 
2379 static struct vendor_data vendor_arm = {
2380 	.fifodepth = 8,
2381 	.max_bpw = 16,
2382 	.unidir = false,
2383 	.extended_cr = false,
2384 	.pl023 = false,
2385 	.loopback = true,
2386 };
2387 
2388 static struct vendor_data vendor_st = {
2389 	.fifodepth = 32,
2390 	.max_bpw = 32,
2391 	.unidir = false,
2392 	.extended_cr = true,
2393 	.pl023 = false,
2394 	.loopback = true,
2395 };
2396 
2397 static struct vendor_data vendor_st_pl023 = {
2398 	.fifodepth = 32,
2399 	.max_bpw = 32,
2400 	.unidir = false,
2401 	.extended_cr = true,
2402 	.pl023 = true,
2403 	.loopback = false,
2404 };
2405 
2406 static struct amba_id pl022_ids[] = {
2407 	{
2408 		/*
2409 		 * ARM PL022 variant, this has a 16bit wide
2410 		 * and 8 locations deep TX/RX FIFO
2411 		 */
2412 		.id	= 0x00041022,
2413 		.mask	= 0x000fffff,
2414 		.data	= &vendor_arm,
2415 	},
2416 	{
2417 		/*
2418 		 * ST Micro derivative, this has 32bit wide
2419 		 * and 32 locations deep TX/RX FIFO
2420 		 */
2421 		.id	= 0x01080022,
2422 		.mask	= 0xffffffff,
2423 		.data	= &vendor_st,
2424 	},
2425 	{
2426 		/*
2427 		 * ST-Ericsson derivative "PL023" (this is not
2428 		 * an official ARM number), this is a PL022 SSP block
2429 		 * stripped to SPI mode only, it has 32bit wide
2430 		 * and 32 locations deep TX/RX FIFO but no extended
2431 		 * CR0/CR1 register
2432 		 */
2433 		.id	= 0x00080023,
2434 		.mask	= 0xffffffff,
2435 		.data	= &vendor_st_pl023,
2436 	},
2437 	{ 0, 0 },
2438 };
2439 
2440 MODULE_DEVICE_TABLE(amba, pl022_ids);
2441 
2442 static struct amba_driver pl022_driver = {
2443 	.drv = {
2444 		.name	= "ssp-pl022",
2445 		.pm	= &pl022_dev_pm_ops,
2446 	},
2447 	.id_table	= pl022_ids,
2448 	.probe		= pl022_probe,
2449 	.remove		= pl022_remove,
2450 };
2451 
2452 static int __init pl022_init(void)
2453 {
2454 	return amba_driver_register(&pl022_driver);
2455 }
2456 subsys_initcall(pl022_init);
2457 
2458 static void __exit pl022_exit(void)
2459 {
2460 	amba_driver_unregister(&pl022_driver);
2461 }
2462 module_exit(pl022_exit);
2463 
2464 MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2465 MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2466 MODULE_LICENSE("GPL");
2467