xref: /openbmc/linux/drivers/spi/spi-pl022.c (revision 3a9a231d)
1 /*
2  * A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
3  *
4  * Copyright (C) 2008-2009 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/workqueue.h>
33 #include <linux/delay.h>
34 #include <linux/clk.h>
35 #include <linux/err.h>
36 #include <linux/amba/bus.h>
37 #include <linux/amba/pl022.h>
38 #include <linux/io.h>
39 #include <linux/slab.h>
40 #include <linux/dmaengine.h>
41 #include <linux/dma-mapping.h>
42 #include <linux/scatterlist.h>
43 #include <linux/pm_runtime.h>
44 
45 /*
46  * This macro is used to define some register default values.
47  * reg is masked with mask, the OR:ed with an (again masked)
48  * val shifted sb steps to the left.
49  */
50 #define SSP_WRITE_BITS(reg, val, mask, sb) \
51  ((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
52 
53 /*
54  * This macro is also used to define some default values.
55  * It will just shift val by sb steps to the left and mask
56  * the result with mask.
57  */
58 #define GEN_MASK_BITS(val, mask, sb) \
59  (((val)<<(sb)) & (mask))
60 
61 #define DRIVE_TX		0
62 #define DO_NOT_DRIVE_TX		1
63 
64 #define DO_NOT_QUEUE_DMA	0
65 #define QUEUE_DMA		1
66 
67 #define RX_TRANSFER		1
68 #define TX_TRANSFER		2
69 
70 /*
71  * Macros to access SSP Registers with their offsets
72  */
73 #define SSP_CR0(r)	(r + 0x000)
74 #define SSP_CR1(r)	(r + 0x004)
75 #define SSP_DR(r)	(r + 0x008)
76 #define SSP_SR(r)	(r + 0x00C)
77 #define SSP_CPSR(r)	(r + 0x010)
78 #define SSP_IMSC(r)	(r + 0x014)
79 #define SSP_RIS(r)	(r + 0x018)
80 #define SSP_MIS(r)	(r + 0x01C)
81 #define SSP_ICR(r)	(r + 0x020)
82 #define SSP_DMACR(r)	(r + 0x024)
83 #define SSP_ITCR(r)	(r + 0x080)
84 #define SSP_ITIP(r)	(r + 0x084)
85 #define SSP_ITOP(r)	(r + 0x088)
86 #define SSP_TDR(r)	(r + 0x08C)
87 
88 #define SSP_PID0(r)	(r + 0xFE0)
89 #define SSP_PID1(r)	(r + 0xFE4)
90 #define SSP_PID2(r)	(r + 0xFE8)
91 #define SSP_PID3(r)	(r + 0xFEC)
92 
93 #define SSP_CID0(r)	(r + 0xFF0)
94 #define SSP_CID1(r)	(r + 0xFF4)
95 #define SSP_CID2(r)	(r + 0xFF8)
96 #define SSP_CID3(r)	(r + 0xFFC)
97 
98 /*
99  * SSP Control Register 0  - SSP_CR0
100  */
101 #define SSP_CR0_MASK_DSS	(0x0FUL << 0)
102 #define SSP_CR0_MASK_FRF	(0x3UL << 4)
103 #define SSP_CR0_MASK_SPO	(0x1UL << 6)
104 #define SSP_CR0_MASK_SPH	(0x1UL << 7)
105 #define SSP_CR0_MASK_SCR	(0xFFUL << 8)
106 
107 /*
108  * The ST version of this block moves som bits
109  * in SSP_CR0 and extends it to 32 bits
110  */
111 #define SSP_CR0_MASK_DSS_ST	(0x1FUL << 0)
112 #define SSP_CR0_MASK_HALFDUP_ST	(0x1UL << 5)
113 #define SSP_CR0_MASK_CSS_ST	(0x1FUL << 16)
114 #define SSP_CR0_MASK_FRF_ST	(0x3UL << 21)
115 
116 /*
117  * SSP Control Register 0  - SSP_CR1
118  */
119 #define SSP_CR1_MASK_LBM	(0x1UL << 0)
120 #define SSP_CR1_MASK_SSE	(0x1UL << 1)
121 #define SSP_CR1_MASK_MS		(0x1UL << 2)
122 #define SSP_CR1_MASK_SOD	(0x1UL << 3)
123 
124 /*
125  * The ST version of this block adds some bits
126  * in SSP_CR1
127  */
128 #define SSP_CR1_MASK_RENDN_ST	(0x1UL << 4)
129 #define SSP_CR1_MASK_TENDN_ST	(0x1UL << 5)
130 #define SSP_CR1_MASK_MWAIT_ST	(0x1UL << 6)
131 #define SSP_CR1_MASK_RXIFLSEL_ST (0x7UL << 7)
132 #define SSP_CR1_MASK_TXIFLSEL_ST (0x7UL << 10)
133 /* This one is only in the PL023 variant */
134 #define SSP_CR1_MASK_FBCLKDEL_ST (0x7UL << 13)
135 
136 /*
137  * SSP Status Register - SSP_SR
138  */
139 #define SSP_SR_MASK_TFE		(0x1UL << 0) /* Transmit FIFO empty */
140 #define SSP_SR_MASK_TNF		(0x1UL << 1) /* Transmit FIFO not full */
141 #define SSP_SR_MASK_RNE		(0x1UL << 2) /* Receive FIFO not empty */
142 #define SSP_SR_MASK_RFF		(0x1UL << 3) /* Receive FIFO full */
143 #define SSP_SR_MASK_BSY		(0x1UL << 4) /* Busy Flag */
144 
145 /*
146  * SSP Clock Prescale Register  - SSP_CPSR
147  */
148 #define SSP_CPSR_MASK_CPSDVSR	(0xFFUL << 0)
149 
150 /*
151  * SSP Interrupt Mask Set/Clear Register - SSP_IMSC
152  */
153 #define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
154 #define SSP_IMSC_MASK_RTIM  (0x1UL << 1) /* Receive timeout Interrupt mask */
155 #define SSP_IMSC_MASK_RXIM  (0x1UL << 2) /* Receive FIFO Interrupt mask */
156 #define SSP_IMSC_MASK_TXIM  (0x1UL << 3) /* Transmit FIFO Interrupt mask */
157 
158 /*
159  * SSP Raw Interrupt Status Register - SSP_RIS
160  */
161 /* Receive Overrun Raw Interrupt status */
162 #define SSP_RIS_MASK_RORRIS		(0x1UL << 0)
163 /* Receive Timeout Raw Interrupt status */
164 #define SSP_RIS_MASK_RTRIS		(0x1UL << 1)
165 /* Receive FIFO Raw Interrupt status */
166 #define SSP_RIS_MASK_RXRIS		(0x1UL << 2)
167 /* Transmit FIFO Raw Interrupt status */
168 #define SSP_RIS_MASK_TXRIS		(0x1UL << 3)
169 
170 /*
171  * SSP Masked Interrupt Status Register - SSP_MIS
172  */
173 /* Receive Overrun Masked Interrupt status */
174 #define SSP_MIS_MASK_RORMIS		(0x1UL << 0)
175 /* Receive Timeout Masked Interrupt status */
176 #define SSP_MIS_MASK_RTMIS		(0x1UL << 1)
177 /* Receive FIFO Masked Interrupt status */
178 #define SSP_MIS_MASK_RXMIS		(0x1UL << 2)
179 /* Transmit FIFO Masked Interrupt status */
180 #define SSP_MIS_MASK_TXMIS		(0x1UL << 3)
181 
182 /*
183  * SSP Interrupt Clear Register - SSP_ICR
184  */
185 /* Receive Overrun Raw Clear Interrupt bit */
186 #define SSP_ICR_MASK_RORIC		(0x1UL << 0)
187 /* Receive Timeout Clear Interrupt bit */
188 #define SSP_ICR_MASK_RTIC		(0x1UL << 1)
189 
190 /*
191  * SSP DMA Control Register - SSP_DMACR
192  */
193 /* Receive DMA Enable bit */
194 #define SSP_DMACR_MASK_RXDMAE		(0x1UL << 0)
195 /* Transmit DMA Enable bit */
196 #define SSP_DMACR_MASK_TXDMAE		(0x1UL << 1)
197 
198 /*
199  * SSP Integration Test control Register - SSP_ITCR
200  */
201 #define SSP_ITCR_MASK_ITEN		(0x1UL << 0)
202 #define SSP_ITCR_MASK_TESTFIFO		(0x1UL << 1)
203 
204 /*
205  * SSP Integration Test Input Register - SSP_ITIP
206  */
207 #define ITIP_MASK_SSPRXD		 (0x1UL << 0)
208 #define ITIP_MASK_SSPFSSIN		 (0x1UL << 1)
209 #define ITIP_MASK_SSPCLKIN		 (0x1UL << 2)
210 #define ITIP_MASK_RXDMAC		 (0x1UL << 3)
211 #define ITIP_MASK_TXDMAC		 (0x1UL << 4)
212 #define ITIP_MASK_SSPTXDIN		 (0x1UL << 5)
213 
214 /*
215  * SSP Integration Test output Register - SSP_ITOP
216  */
217 #define ITOP_MASK_SSPTXD		 (0x1UL << 0)
218 #define ITOP_MASK_SSPFSSOUT		 (0x1UL << 1)
219 #define ITOP_MASK_SSPCLKOUT		 (0x1UL << 2)
220 #define ITOP_MASK_SSPOEn		 (0x1UL << 3)
221 #define ITOP_MASK_SSPCTLOEn		 (0x1UL << 4)
222 #define ITOP_MASK_RORINTR		 (0x1UL << 5)
223 #define ITOP_MASK_RTINTR		 (0x1UL << 6)
224 #define ITOP_MASK_RXINTR		 (0x1UL << 7)
225 #define ITOP_MASK_TXINTR		 (0x1UL << 8)
226 #define ITOP_MASK_INTR			 (0x1UL << 9)
227 #define ITOP_MASK_RXDMABREQ		 (0x1UL << 10)
228 #define ITOP_MASK_RXDMASREQ		 (0x1UL << 11)
229 #define ITOP_MASK_TXDMABREQ		 (0x1UL << 12)
230 #define ITOP_MASK_TXDMASREQ		 (0x1UL << 13)
231 
232 /*
233  * SSP Test Data Register - SSP_TDR
234  */
235 #define TDR_MASK_TESTDATA		(0xFFFFFFFF)
236 
237 /*
238  * Message State
239  * we use the spi_message.state (void *) pointer to
240  * hold a single state value, that's why all this
241  * (void *) casting is done here.
242  */
243 #define STATE_START			((void *) 0)
244 #define STATE_RUNNING			((void *) 1)
245 #define STATE_DONE			((void *) 2)
246 #define STATE_ERROR			((void *) -1)
247 
248 /*
249  * SSP State - Whether Enabled or Disabled
250  */
251 #define SSP_DISABLED			(0)
252 #define SSP_ENABLED			(1)
253 
254 /*
255  * SSP DMA State - Whether DMA Enabled or Disabled
256  */
257 #define SSP_DMA_DISABLED		(0)
258 #define SSP_DMA_ENABLED			(1)
259 
260 /*
261  * SSP Clock Defaults
262  */
263 #define SSP_DEFAULT_CLKRATE 0x2
264 #define SSP_DEFAULT_PRESCALE 0x40
265 
266 /*
267  * SSP Clock Parameter ranges
268  */
269 #define CPSDVR_MIN 0x02
270 #define CPSDVR_MAX 0xFE
271 #define SCR_MIN 0x00
272 #define SCR_MAX 0xFF
273 
274 /*
275  * SSP Interrupt related Macros
276  */
277 #define DEFAULT_SSP_REG_IMSC  0x0UL
278 #define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
279 #define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
280 
281 #define CLEAR_ALL_INTERRUPTS  0x3
282 
283 #define SPI_POLLING_TIMEOUT 1000
284 
285 /*
286  * The type of reading going on on this chip
287  */
288 enum ssp_reading {
289 	READING_NULL,
290 	READING_U8,
291 	READING_U16,
292 	READING_U32
293 };
294 
295 /**
296  * The type of writing going on on this chip
297  */
298 enum ssp_writing {
299 	WRITING_NULL,
300 	WRITING_U8,
301 	WRITING_U16,
302 	WRITING_U32
303 };
304 
305 /**
306  * struct vendor_data - vendor-specific config parameters
307  * for PL022 derivates
308  * @fifodepth: depth of FIFOs (both)
309  * @max_bpw: maximum number of bits per word
310  * @unidir: supports unidirection transfers
311  * @extended_cr: 32 bit wide control register 0 with extra
312  * features and extra features in CR1 as found in the ST variants
313  * @pl023: supports a subset of the ST extensions called "PL023"
314  */
315 struct vendor_data {
316 	int fifodepth;
317 	int max_bpw;
318 	bool unidir;
319 	bool extended_cr;
320 	bool pl023;
321 	bool loopback;
322 };
323 
324 /**
325  * struct pl022 - This is the private SSP driver data structure
326  * @adev: AMBA device model hookup
327  * @vendor: vendor data for the IP block
328  * @phybase: the physical memory where the SSP device resides
329  * @virtbase: the virtual memory where the SSP is mapped
330  * @clk: outgoing clock "SPICLK" for the SPI bus
331  * @master: SPI framework hookup
332  * @master_info: controller-specific data from machine setup
333  * @workqueue: a workqueue on which any spi_message request is queued
334  * @pump_messages: work struct for scheduling work to the workqueue
335  * @queue_lock: spinlock to syncronise access to message queue
336  * @queue: message queue
337  * @busy: workqueue is busy
338  * @running: workqueue is running
339  * @pump_transfers: Tasklet used in Interrupt Transfer mode
340  * @cur_msg: Pointer to current spi_message being processed
341  * @cur_transfer: Pointer to current spi_transfer
342  * @cur_chip: pointer to current clients chip(assigned from controller_state)
343  * @tx: current position in TX buffer to be read
344  * @tx_end: end position in TX buffer to be read
345  * @rx: current position in RX buffer to be written
346  * @rx_end: end position in RX buffer to be written
347  * @read: the type of read currently going on
348  * @write: the type of write currently going on
349  * @exp_fifo_level: expected FIFO level
350  * @dma_rx_channel: optional channel for RX DMA
351  * @dma_tx_channel: optional channel for TX DMA
352  * @sgt_rx: scattertable for the RX transfer
353  * @sgt_tx: scattertable for the TX transfer
354  * @dummypage: a dummy page used for driving data on the bus with DMA
355  */
356 struct pl022 {
357 	struct amba_device		*adev;
358 	struct vendor_data		*vendor;
359 	resource_size_t			phybase;
360 	void __iomem			*virtbase;
361 	struct clk			*clk;
362 	struct spi_master		*master;
363 	struct pl022_ssp_controller	*master_info;
364 	/* Driver message queue */
365 	struct workqueue_struct		*workqueue;
366 	struct work_struct		pump_messages;
367 	spinlock_t			queue_lock;
368 	struct list_head		queue;
369 	bool				busy;
370 	bool				running;
371 	/* Message transfer pump */
372 	struct tasklet_struct		pump_transfers;
373 	struct spi_message		*cur_msg;
374 	struct spi_transfer		*cur_transfer;
375 	struct chip_data		*cur_chip;
376 	void				*tx;
377 	void				*tx_end;
378 	void				*rx;
379 	void				*rx_end;
380 	enum ssp_reading		read;
381 	enum ssp_writing		write;
382 	u32				exp_fifo_level;
383 	enum ssp_rx_level_trig		rx_lev_trig;
384 	enum ssp_tx_level_trig		tx_lev_trig;
385 	/* DMA settings */
386 #ifdef CONFIG_DMA_ENGINE
387 	struct dma_chan			*dma_rx_channel;
388 	struct dma_chan			*dma_tx_channel;
389 	struct sg_table			sgt_rx;
390 	struct sg_table			sgt_tx;
391 	char				*dummypage;
392 #endif
393 };
394 
395 /**
396  * struct chip_data - To maintain runtime state of SSP for each client chip
397  * @cr0: Value of control register CR0 of SSP - on later ST variants this
398  *       register is 32 bits wide rather than just 16
399  * @cr1: Value of control register CR1 of SSP
400  * @dmacr: Value of DMA control Register of SSP
401  * @cpsr: Value of Clock prescale register
402  * @n_bytes: how many bytes(power of 2) reqd for a given data width of client
403  * @enable_dma: Whether to enable DMA or not
404  * @read: function ptr to be used to read when doing xfer for this chip
405  * @write: function ptr to be used to write when doing xfer for this chip
406  * @cs_control: chip select callback provided by chip
407  * @xfer_type: polling/interrupt/DMA
408  *
409  * Runtime state of the SSP controller, maintained per chip,
410  * This would be set according to the current message that would be served
411  */
412 struct chip_data {
413 	u32 cr0;
414 	u16 cr1;
415 	u16 dmacr;
416 	u16 cpsr;
417 	u8 n_bytes;
418 	bool enable_dma;
419 	enum ssp_reading read;
420 	enum ssp_writing write;
421 	void (*cs_control) (u32 command);
422 	int xfer_type;
423 };
424 
425 /**
426  * null_cs_control - Dummy chip select function
427  * @command: select/delect the chip
428  *
429  * If no chip select function is provided by client this is used as dummy
430  * chip select
431  */
432 static void null_cs_control(u32 command)
433 {
434 	pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
435 }
436 
437 /**
438  * giveback - current spi_message is over, schedule next message and call
439  * callback of this message. Assumes that caller already
440  * set message->status; dma and pio irqs are blocked
441  * @pl022: SSP driver private data structure
442  */
443 static void giveback(struct pl022 *pl022)
444 {
445 	struct spi_transfer *last_transfer;
446 	unsigned long flags;
447 	struct spi_message *msg;
448 	void (*curr_cs_control) (u32 command);
449 
450 	/*
451 	 * This local reference to the chip select function
452 	 * is needed because we set curr_chip to NULL
453 	 * as a step toward termininating the message.
454 	 */
455 	curr_cs_control = pl022->cur_chip->cs_control;
456 	spin_lock_irqsave(&pl022->queue_lock, flags);
457 	msg = pl022->cur_msg;
458 	pl022->cur_msg = NULL;
459 	pl022->cur_transfer = NULL;
460 	pl022->cur_chip = NULL;
461 	queue_work(pl022->workqueue, &pl022->pump_messages);
462 	spin_unlock_irqrestore(&pl022->queue_lock, flags);
463 
464 	last_transfer = list_entry(msg->transfers.prev,
465 					struct spi_transfer,
466 					transfer_list);
467 
468 	/* Delay if requested before any change in chip select */
469 	if (last_transfer->delay_usecs)
470 		/*
471 		 * FIXME: This runs in interrupt context.
472 		 * Is this really smart?
473 		 */
474 		udelay(last_transfer->delay_usecs);
475 
476 	/*
477 	 * Drop chip select UNLESS cs_change is true or we are returning
478 	 * a message with an error, or next message is for another chip
479 	 */
480 	if (!last_transfer->cs_change)
481 		curr_cs_control(SSP_CHIP_DESELECT);
482 	else {
483 		struct spi_message *next_msg;
484 
485 		/* Holding of cs was hinted, but we need to make sure
486 		 * the next message is for the same chip.  Don't waste
487 		 * time with the following tests unless this was hinted.
488 		 *
489 		 * We cannot postpone this until pump_messages, because
490 		 * after calling msg->complete (below) the driver that
491 		 * sent the current message could be unloaded, which
492 		 * could invalidate the cs_control() callback...
493 		 */
494 
495 		/* get a pointer to the next message, if any */
496 		spin_lock_irqsave(&pl022->queue_lock, flags);
497 		if (list_empty(&pl022->queue))
498 			next_msg = NULL;
499 		else
500 			next_msg = list_entry(pl022->queue.next,
501 					struct spi_message, queue);
502 		spin_unlock_irqrestore(&pl022->queue_lock, flags);
503 
504 		/* see if the next and current messages point
505 		 * to the same chip
506 		 */
507 		if (next_msg && next_msg->spi != msg->spi)
508 			next_msg = NULL;
509 		if (!next_msg || msg->state == STATE_ERROR)
510 			curr_cs_control(SSP_CHIP_DESELECT);
511 	}
512 	msg->state = NULL;
513 	if (msg->complete)
514 		msg->complete(msg->context);
515 	/* This message is completed, so let's turn off the clocks & power */
516 	pm_runtime_put(&pl022->adev->dev);
517 }
518 
519 /**
520  * flush - flush the FIFO to reach a clean state
521  * @pl022: SSP driver private data structure
522  */
523 static int flush(struct pl022 *pl022)
524 {
525 	unsigned long limit = loops_per_jiffy << 1;
526 
527 	dev_dbg(&pl022->adev->dev, "flush\n");
528 	do {
529 		while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
530 			readw(SSP_DR(pl022->virtbase));
531 	} while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
532 
533 	pl022->exp_fifo_level = 0;
534 
535 	return limit;
536 }
537 
538 /**
539  * restore_state - Load configuration of current chip
540  * @pl022: SSP driver private data structure
541  */
542 static void restore_state(struct pl022 *pl022)
543 {
544 	struct chip_data *chip = pl022->cur_chip;
545 
546 	if (pl022->vendor->extended_cr)
547 		writel(chip->cr0, SSP_CR0(pl022->virtbase));
548 	else
549 		writew(chip->cr0, SSP_CR0(pl022->virtbase));
550 	writew(chip->cr1, SSP_CR1(pl022->virtbase));
551 	writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
552 	writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
553 	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
554 	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
555 }
556 
557 /*
558  * Default SSP Register Values
559  */
560 #define DEFAULT_SSP_REG_CR0 ( \
561 	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0)	| \
562 	GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 4) | \
563 	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
564 	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
565 	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
566 )
567 
568 /* ST versions have slightly different bit layout */
569 #define DEFAULT_SSP_REG_CR0_ST ( \
570 	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0)	| \
571 	GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP_ST, 5) | \
572 	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
573 	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
574 	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
575 	GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS_ST, 16)	| \
576 	GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF_ST, 21) \
577 )
578 
579 /* The PL023 version is slightly different again */
580 #define DEFAULT_SSP_REG_CR0_ST_PL023 ( \
581 	GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS_ST, 0)	| \
582 	GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
583 	GEN_MASK_BITS(SSP_CLK_SECOND_EDGE, SSP_CR0_MASK_SPH, 7) | \
584 	GEN_MASK_BITS(SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) \
585 )
586 
587 #define DEFAULT_SSP_REG_CR1 ( \
588 	GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
589 	GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
590 	GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
591 	GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) \
592 )
593 
594 /* ST versions extend this register to use all 16 bits */
595 #define DEFAULT_SSP_REG_CR1_ST ( \
596 	DEFAULT_SSP_REG_CR1 | \
597 	GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
598 	GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
599 	GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT_ST, 6) |\
600 	GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
601 	GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) \
602 )
603 
604 /*
605  * The PL023 variant has further differences: no loopback mode, no microwire
606  * support, and a new clock feedback delay setting.
607  */
608 #define DEFAULT_SSP_REG_CR1_ST_PL023 ( \
609 	GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
610 	GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
611 	GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
612 	GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN_ST, 4) | \
613 	GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN_ST, 5) | \
614 	GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL_ST, 7) | \
615 	GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL_ST, 10) | \
616 	GEN_MASK_BITS(SSP_FEEDBACK_CLK_DELAY_NONE, SSP_CR1_MASK_FBCLKDEL_ST, 13) \
617 )
618 
619 #define DEFAULT_SSP_REG_CPSR ( \
620 	GEN_MASK_BITS(SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
621 )
622 
623 #define DEFAULT_SSP_REG_DMACR (\
624 	GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
625 	GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
626 )
627 
628 /**
629  * load_ssp_default_config - Load default configuration for SSP
630  * @pl022: SSP driver private data structure
631  */
632 static void load_ssp_default_config(struct pl022 *pl022)
633 {
634 	if (pl022->vendor->pl023) {
635 		writel(DEFAULT_SSP_REG_CR0_ST_PL023, SSP_CR0(pl022->virtbase));
636 		writew(DEFAULT_SSP_REG_CR1_ST_PL023, SSP_CR1(pl022->virtbase));
637 	} else if (pl022->vendor->extended_cr) {
638 		writel(DEFAULT_SSP_REG_CR0_ST, SSP_CR0(pl022->virtbase));
639 		writew(DEFAULT_SSP_REG_CR1_ST, SSP_CR1(pl022->virtbase));
640 	} else {
641 		writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
642 		writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
643 	}
644 	writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
645 	writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
646 	writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
647 	writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
648 }
649 
650 /**
651  * This will write to TX and read from RX according to the parameters
652  * set in pl022.
653  */
654 static void readwriter(struct pl022 *pl022)
655 {
656 
657 	/*
658 	 * The FIFO depth is different between primecell variants.
659 	 * I believe filling in too much in the FIFO might cause
660 	 * errons in 8bit wide transfers on ARM variants (just 8 words
661 	 * FIFO, means only 8x8 = 64 bits in FIFO) at least.
662 	 *
663 	 * To prevent this issue, the TX FIFO is only filled to the
664 	 * unused RX FIFO fill length, regardless of what the TX
665 	 * FIFO status flag indicates.
666 	 */
667 	dev_dbg(&pl022->adev->dev,
668 		"%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
669 		__func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
670 
671 	/* Read as much as you can */
672 	while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
673 	       && (pl022->rx < pl022->rx_end)) {
674 		switch (pl022->read) {
675 		case READING_NULL:
676 			readw(SSP_DR(pl022->virtbase));
677 			break;
678 		case READING_U8:
679 			*(u8 *) (pl022->rx) =
680 				readw(SSP_DR(pl022->virtbase)) & 0xFFU;
681 			break;
682 		case READING_U16:
683 			*(u16 *) (pl022->rx) =
684 				(u16) readw(SSP_DR(pl022->virtbase));
685 			break;
686 		case READING_U32:
687 			*(u32 *) (pl022->rx) =
688 				readl(SSP_DR(pl022->virtbase));
689 			break;
690 		}
691 		pl022->rx += (pl022->cur_chip->n_bytes);
692 		pl022->exp_fifo_level--;
693 	}
694 	/*
695 	 * Write as much as possible up to the RX FIFO size
696 	 */
697 	while ((pl022->exp_fifo_level < pl022->vendor->fifodepth)
698 	       && (pl022->tx < pl022->tx_end)) {
699 		switch (pl022->write) {
700 		case WRITING_NULL:
701 			writew(0x0, SSP_DR(pl022->virtbase));
702 			break;
703 		case WRITING_U8:
704 			writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
705 			break;
706 		case WRITING_U16:
707 			writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
708 			break;
709 		case WRITING_U32:
710 			writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
711 			break;
712 		}
713 		pl022->tx += (pl022->cur_chip->n_bytes);
714 		pl022->exp_fifo_level++;
715 		/*
716 		 * This inner reader takes care of things appearing in the RX
717 		 * FIFO as we're transmitting. This will happen a lot since the
718 		 * clock starts running when you put things into the TX FIFO,
719 		 * and then things are continuously clocked into the RX FIFO.
720 		 */
721 		while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
722 		       && (pl022->rx < pl022->rx_end)) {
723 			switch (pl022->read) {
724 			case READING_NULL:
725 				readw(SSP_DR(pl022->virtbase));
726 				break;
727 			case READING_U8:
728 				*(u8 *) (pl022->rx) =
729 					readw(SSP_DR(pl022->virtbase)) & 0xFFU;
730 				break;
731 			case READING_U16:
732 				*(u16 *) (pl022->rx) =
733 					(u16) readw(SSP_DR(pl022->virtbase));
734 				break;
735 			case READING_U32:
736 				*(u32 *) (pl022->rx) =
737 					readl(SSP_DR(pl022->virtbase));
738 				break;
739 			}
740 			pl022->rx += (pl022->cur_chip->n_bytes);
741 			pl022->exp_fifo_level--;
742 		}
743 	}
744 	/*
745 	 * When we exit here the TX FIFO should be full and the RX FIFO
746 	 * should be empty
747 	 */
748 }
749 
750 /**
751  * next_transfer - Move to the Next transfer in the current spi message
752  * @pl022: SSP driver private data structure
753  *
754  * This function moves though the linked list of spi transfers in the
755  * current spi message and returns with the state of current spi
756  * message i.e whether its last transfer is done(STATE_DONE) or
757  * Next transfer is ready(STATE_RUNNING)
758  */
759 static void *next_transfer(struct pl022 *pl022)
760 {
761 	struct spi_message *msg = pl022->cur_msg;
762 	struct spi_transfer *trans = pl022->cur_transfer;
763 
764 	/* Move to next transfer */
765 	if (trans->transfer_list.next != &msg->transfers) {
766 		pl022->cur_transfer =
767 		    list_entry(trans->transfer_list.next,
768 			       struct spi_transfer, transfer_list);
769 		return STATE_RUNNING;
770 	}
771 	return STATE_DONE;
772 }
773 
774 /*
775  * This DMA functionality is only compiled in if we have
776  * access to the generic DMA devices/DMA engine.
777  */
778 #ifdef CONFIG_DMA_ENGINE
779 static void unmap_free_dma_scatter(struct pl022 *pl022)
780 {
781 	/* Unmap and free the SG tables */
782 	dma_unmap_sg(pl022->dma_tx_channel->device->dev, pl022->sgt_tx.sgl,
783 		     pl022->sgt_tx.nents, DMA_TO_DEVICE);
784 	dma_unmap_sg(pl022->dma_rx_channel->device->dev, pl022->sgt_rx.sgl,
785 		     pl022->sgt_rx.nents, DMA_FROM_DEVICE);
786 	sg_free_table(&pl022->sgt_rx);
787 	sg_free_table(&pl022->sgt_tx);
788 }
789 
790 static void dma_callback(void *data)
791 {
792 	struct pl022 *pl022 = data;
793 	struct spi_message *msg = pl022->cur_msg;
794 
795 	BUG_ON(!pl022->sgt_rx.sgl);
796 
797 #ifdef VERBOSE_DEBUG
798 	/*
799 	 * Optionally dump out buffers to inspect contents, this is
800 	 * good if you want to convince yourself that the loopback
801 	 * read/write contents are the same, when adopting to a new
802 	 * DMA engine.
803 	 */
804 	{
805 		struct scatterlist *sg;
806 		unsigned int i;
807 
808 		dma_sync_sg_for_cpu(&pl022->adev->dev,
809 				    pl022->sgt_rx.sgl,
810 				    pl022->sgt_rx.nents,
811 				    DMA_FROM_DEVICE);
812 
813 		for_each_sg(pl022->sgt_rx.sgl, sg, pl022->sgt_rx.nents, i) {
814 			dev_dbg(&pl022->adev->dev, "SPI RX SG ENTRY: %d", i);
815 			print_hex_dump(KERN_ERR, "SPI RX: ",
816 				       DUMP_PREFIX_OFFSET,
817 				       16,
818 				       1,
819 				       sg_virt(sg),
820 				       sg_dma_len(sg),
821 				       1);
822 		}
823 		for_each_sg(pl022->sgt_tx.sgl, sg, pl022->sgt_tx.nents, i) {
824 			dev_dbg(&pl022->adev->dev, "SPI TX SG ENTRY: %d", i);
825 			print_hex_dump(KERN_ERR, "SPI TX: ",
826 				       DUMP_PREFIX_OFFSET,
827 				       16,
828 				       1,
829 				       sg_virt(sg),
830 				       sg_dma_len(sg),
831 				       1);
832 		}
833 	}
834 #endif
835 
836 	unmap_free_dma_scatter(pl022);
837 
838 	/* Update total bytes transferred */
839 	msg->actual_length += pl022->cur_transfer->len;
840 	if (pl022->cur_transfer->cs_change)
841 		pl022->cur_chip->
842 			cs_control(SSP_CHIP_DESELECT);
843 
844 	/* Move to next transfer */
845 	msg->state = next_transfer(pl022);
846 	tasklet_schedule(&pl022->pump_transfers);
847 }
848 
849 static void setup_dma_scatter(struct pl022 *pl022,
850 			      void *buffer,
851 			      unsigned int length,
852 			      struct sg_table *sgtab)
853 {
854 	struct scatterlist *sg;
855 	int bytesleft = length;
856 	void *bufp = buffer;
857 	int mapbytes;
858 	int i;
859 
860 	if (buffer) {
861 		for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
862 			/*
863 			 * If there are less bytes left than what fits
864 			 * in the current page (plus page alignment offset)
865 			 * we just feed in this, else we stuff in as much
866 			 * as we can.
867 			 */
868 			if (bytesleft < (PAGE_SIZE - offset_in_page(bufp)))
869 				mapbytes = bytesleft;
870 			else
871 				mapbytes = PAGE_SIZE - offset_in_page(bufp);
872 			sg_set_page(sg, virt_to_page(bufp),
873 				    mapbytes, offset_in_page(bufp));
874 			bufp += mapbytes;
875 			bytesleft -= mapbytes;
876 			dev_dbg(&pl022->adev->dev,
877 				"set RX/TX target page @ %p, %d bytes, %d left\n",
878 				bufp, mapbytes, bytesleft);
879 		}
880 	} else {
881 		/* Map the dummy buffer on every page */
882 		for_each_sg(sgtab->sgl, sg, sgtab->nents, i) {
883 			if (bytesleft < PAGE_SIZE)
884 				mapbytes = bytesleft;
885 			else
886 				mapbytes = PAGE_SIZE;
887 			sg_set_page(sg, virt_to_page(pl022->dummypage),
888 				    mapbytes, 0);
889 			bytesleft -= mapbytes;
890 			dev_dbg(&pl022->adev->dev,
891 				"set RX/TX to dummy page %d bytes, %d left\n",
892 				mapbytes, bytesleft);
893 
894 		}
895 	}
896 	BUG_ON(bytesleft);
897 }
898 
899 /**
900  * configure_dma - configures the channels for the next transfer
901  * @pl022: SSP driver's private data structure
902  */
903 static int configure_dma(struct pl022 *pl022)
904 {
905 	struct dma_slave_config rx_conf = {
906 		.src_addr = SSP_DR(pl022->phybase),
907 		.direction = DMA_FROM_DEVICE,
908 	};
909 	struct dma_slave_config tx_conf = {
910 		.dst_addr = SSP_DR(pl022->phybase),
911 		.direction = DMA_TO_DEVICE,
912 	};
913 	unsigned int pages;
914 	int ret;
915 	int rx_sglen, tx_sglen;
916 	struct dma_chan *rxchan = pl022->dma_rx_channel;
917 	struct dma_chan *txchan = pl022->dma_tx_channel;
918 	struct dma_async_tx_descriptor *rxdesc;
919 	struct dma_async_tx_descriptor *txdesc;
920 
921 	/* Check that the channels are available */
922 	if (!rxchan || !txchan)
923 		return -ENODEV;
924 
925 	/*
926 	 * If supplied, the DMA burstsize should equal the FIFO trigger level.
927 	 * Notice that the DMA engine uses one-to-one mapping. Since we can
928 	 * not trigger on 2 elements this needs explicit mapping rather than
929 	 * calculation.
930 	 */
931 	switch (pl022->rx_lev_trig) {
932 	case SSP_RX_1_OR_MORE_ELEM:
933 		rx_conf.src_maxburst = 1;
934 		break;
935 	case SSP_RX_4_OR_MORE_ELEM:
936 		rx_conf.src_maxburst = 4;
937 		break;
938 	case SSP_RX_8_OR_MORE_ELEM:
939 		rx_conf.src_maxburst = 8;
940 		break;
941 	case SSP_RX_16_OR_MORE_ELEM:
942 		rx_conf.src_maxburst = 16;
943 		break;
944 	case SSP_RX_32_OR_MORE_ELEM:
945 		rx_conf.src_maxburst = 32;
946 		break;
947 	default:
948 		rx_conf.src_maxburst = pl022->vendor->fifodepth >> 1;
949 		break;
950 	}
951 
952 	switch (pl022->tx_lev_trig) {
953 	case SSP_TX_1_OR_MORE_EMPTY_LOC:
954 		tx_conf.dst_maxburst = 1;
955 		break;
956 	case SSP_TX_4_OR_MORE_EMPTY_LOC:
957 		tx_conf.dst_maxburst = 4;
958 		break;
959 	case SSP_TX_8_OR_MORE_EMPTY_LOC:
960 		tx_conf.dst_maxburst = 8;
961 		break;
962 	case SSP_TX_16_OR_MORE_EMPTY_LOC:
963 		tx_conf.dst_maxburst = 16;
964 		break;
965 	case SSP_TX_32_OR_MORE_EMPTY_LOC:
966 		tx_conf.dst_maxburst = 32;
967 		break;
968 	default:
969 		tx_conf.dst_maxburst = pl022->vendor->fifodepth >> 1;
970 		break;
971 	}
972 
973 	switch (pl022->read) {
974 	case READING_NULL:
975 		/* Use the same as for writing */
976 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
977 		break;
978 	case READING_U8:
979 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
980 		break;
981 	case READING_U16:
982 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
983 		break;
984 	case READING_U32:
985 		rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
986 		break;
987 	}
988 
989 	switch (pl022->write) {
990 	case WRITING_NULL:
991 		/* Use the same as for reading */
992 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
993 		break;
994 	case WRITING_U8:
995 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
996 		break;
997 	case WRITING_U16:
998 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
999 		break;
1000 	case WRITING_U32:
1001 		tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1002 		break;
1003 	}
1004 
1005 	/* SPI pecularity: we need to read and write the same width */
1006 	if (rx_conf.src_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1007 		rx_conf.src_addr_width = tx_conf.dst_addr_width;
1008 	if (tx_conf.dst_addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED)
1009 		tx_conf.dst_addr_width = rx_conf.src_addr_width;
1010 	BUG_ON(rx_conf.src_addr_width != tx_conf.dst_addr_width);
1011 
1012 	dmaengine_slave_config(rxchan, &rx_conf);
1013 	dmaengine_slave_config(txchan, &tx_conf);
1014 
1015 	/* Create sglists for the transfers */
1016 	pages = DIV_ROUND_UP(pl022->cur_transfer->len, PAGE_SIZE);
1017 	dev_dbg(&pl022->adev->dev, "using %d pages for transfer\n", pages);
1018 
1019 	ret = sg_alloc_table(&pl022->sgt_rx, pages, GFP_ATOMIC);
1020 	if (ret)
1021 		goto err_alloc_rx_sg;
1022 
1023 	ret = sg_alloc_table(&pl022->sgt_tx, pages, GFP_ATOMIC);
1024 	if (ret)
1025 		goto err_alloc_tx_sg;
1026 
1027 	/* Fill in the scatterlists for the RX+TX buffers */
1028 	setup_dma_scatter(pl022, pl022->rx,
1029 			  pl022->cur_transfer->len, &pl022->sgt_rx);
1030 	setup_dma_scatter(pl022, pl022->tx,
1031 			  pl022->cur_transfer->len, &pl022->sgt_tx);
1032 
1033 	/* Map DMA buffers */
1034 	rx_sglen = dma_map_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1035 			   pl022->sgt_rx.nents, DMA_FROM_DEVICE);
1036 	if (!rx_sglen)
1037 		goto err_rx_sgmap;
1038 
1039 	tx_sglen = dma_map_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1040 			   pl022->sgt_tx.nents, DMA_TO_DEVICE);
1041 	if (!tx_sglen)
1042 		goto err_tx_sgmap;
1043 
1044 	/* Send both scatterlists */
1045 	rxdesc = rxchan->device->device_prep_slave_sg(rxchan,
1046 				      pl022->sgt_rx.sgl,
1047 				      rx_sglen,
1048 				      DMA_FROM_DEVICE,
1049 				      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1050 	if (!rxdesc)
1051 		goto err_rxdesc;
1052 
1053 	txdesc = txchan->device->device_prep_slave_sg(txchan,
1054 				      pl022->sgt_tx.sgl,
1055 				      tx_sglen,
1056 				      DMA_TO_DEVICE,
1057 				      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1058 	if (!txdesc)
1059 		goto err_txdesc;
1060 
1061 	/* Put the callback on the RX transfer only, that should finish last */
1062 	rxdesc->callback = dma_callback;
1063 	rxdesc->callback_param = pl022;
1064 
1065 	/* Submit and fire RX and TX with TX last so we're ready to read! */
1066 	dmaengine_submit(rxdesc);
1067 	dmaengine_submit(txdesc);
1068 	dma_async_issue_pending(rxchan);
1069 	dma_async_issue_pending(txchan);
1070 
1071 	return 0;
1072 
1073 err_txdesc:
1074 	dmaengine_terminate_all(txchan);
1075 err_rxdesc:
1076 	dmaengine_terminate_all(rxchan);
1077 	dma_unmap_sg(txchan->device->dev, pl022->sgt_tx.sgl,
1078 		     pl022->sgt_tx.nents, DMA_TO_DEVICE);
1079 err_tx_sgmap:
1080 	dma_unmap_sg(rxchan->device->dev, pl022->sgt_rx.sgl,
1081 		     pl022->sgt_tx.nents, DMA_FROM_DEVICE);
1082 err_rx_sgmap:
1083 	sg_free_table(&pl022->sgt_tx);
1084 err_alloc_tx_sg:
1085 	sg_free_table(&pl022->sgt_rx);
1086 err_alloc_rx_sg:
1087 	return -ENOMEM;
1088 }
1089 
1090 static int __init pl022_dma_probe(struct pl022 *pl022)
1091 {
1092 	dma_cap_mask_t mask;
1093 
1094 	/* Try to acquire a generic DMA engine slave channel */
1095 	dma_cap_zero(mask);
1096 	dma_cap_set(DMA_SLAVE, mask);
1097 	/*
1098 	 * We need both RX and TX channels to do DMA, else do none
1099 	 * of them.
1100 	 */
1101 	pl022->dma_rx_channel = dma_request_channel(mask,
1102 					    pl022->master_info->dma_filter,
1103 					    pl022->master_info->dma_rx_param);
1104 	if (!pl022->dma_rx_channel) {
1105 		dev_dbg(&pl022->adev->dev, "no RX DMA channel!\n");
1106 		goto err_no_rxchan;
1107 	}
1108 
1109 	pl022->dma_tx_channel = dma_request_channel(mask,
1110 					    pl022->master_info->dma_filter,
1111 					    pl022->master_info->dma_tx_param);
1112 	if (!pl022->dma_tx_channel) {
1113 		dev_dbg(&pl022->adev->dev, "no TX DMA channel!\n");
1114 		goto err_no_txchan;
1115 	}
1116 
1117 	pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
1118 	if (!pl022->dummypage) {
1119 		dev_dbg(&pl022->adev->dev, "no DMA dummypage!\n");
1120 		goto err_no_dummypage;
1121 	}
1122 
1123 	dev_info(&pl022->adev->dev, "setup for DMA on RX %s, TX %s\n",
1124 		 dma_chan_name(pl022->dma_rx_channel),
1125 		 dma_chan_name(pl022->dma_tx_channel));
1126 
1127 	return 0;
1128 
1129 err_no_dummypage:
1130 	dma_release_channel(pl022->dma_tx_channel);
1131 err_no_txchan:
1132 	dma_release_channel(pl022->dma_rx_channel);
1133 	pl022->dma_rx_channel = NULL;
1134 err_no_rxchan:
1135 	dev_err(&pl022->adev->dev,
1136 			"Failed to work in dma mode, work without dma!\n");
1137 	return -ENODEV;
1138 }
1139 
1140 static void terminate_dma(struct pl022 *pl022)
1141 {
1142 	struct dma_chan *rxchan = pl022->dma_rx_channel;
1143 	struct dma_chan *txchan = pl022->dma_tx_channel;
1144 
1145 	dmaengine_terminate_all(rxchan);
1146 	dmaengine_terminate_all(txchan);
1147 	unmap_free_dma_scatter(pl022);
1148 }
1149 
1150 static void pl022_dma_remove(struct pl022 *pl022)
1151 {
1152 	if (pl022->busy)
1153 		terminate_dma(pl022);
1154 	if (pl022->dma_tx_channel)
1155 		dma_release_channel(pl022->dma_tx_channel);
1156 	if (pl022->dma_rx_channel)
1157 		dma_release_channel(pl022->dma_rx_channel);
1158 	kfree(pl022->dummypage);
1159 }
1160 
1161 #else
1162 static inline int configure_dma(struct pl022 *pl022)
1163 {
1164 	return -ENODEV;
1165 }
1166 
1167 static inline int pl022_dma_probe(struct pl022 *pl022)
1168 {
1169 	return 0;
1170 }
1171 
1172 static inline void pl022_dma_remove(struct pl022 *pl022)
1173 {
1174 }
1175 #endif
1176 
1177 /**
1178  * pl022_interrupt_handler - Interrupt handler for SSP controller
1179  *
1180  * This function handles interrupts generated for an interrupt based transfer.
1181  * If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
1182  * current message's state as STATE_ERROR and schedule the tasklet
1183  * pump_transfers which will do the postprocessing of the current message by
1184  * calling giveback(). Otherwise it reads data from RX FIFO till there is no
1185  * more data, and writes data in TX FIFO till it is not full. If we complete
1186  * the transfer we move to the next transfer and schedule the tasklet.
1187  */
1188 static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
1189 {
1190 	struct pl022 *pl022 = dev_id;
1191 	struct spi_message *msg = pl022->cur_msg;
1192 	u16 irq_status = 0;
1193 	u16 flag = 0;
1194 
1195 	if (unlikely(!msg)) {
1196 		dev_err(&pl022->adev->dev,
1197 			"bad message state in interrupt handler");
1198 		/* Never fail */
1199 		return IRQ_HANDLED;
1200 	}
1201 
1202 	/* Read the Interrupt Status Register */
1203 	irq_status = readw(SSP_MIS(pl022->virtbase));
1204 
1205 	if (unlikely(!irq_status))
1206 		return IRQ_NONE;
1207 
1208 	/*
1209 	 * This handles the FIFO interrupts, the timeout
1210 	 * interrupts are flatly ignored, they cannot be
1211 	 * trusted.
1212 	 */
1213 	if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
1214 		/*
1215 		 * Overrun interrupt - bail out since our Data has been
1216 		 * corrupted
1217 		 */
1218 		dev_err(&pl022->adev->dev, "FIFO overrun\n");
1219 		if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
1220 			dev_err(&pl022->adev->dev,
1221 				"RXFIFO is full\n");
1222 		if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
1223 			dev_err(&pl022->adev->dev,
1224 				"TXFIFO is full\n");
1225 
1226 		/*
1227 		 * Disable and clear interrupts, disable SSP,
1228 		 * mark message with bad status so it can be
1229 		 * retried.
1230 		 */
1231 		writew(DISABLE_ALL_INTERRUPTS,
1232 		       SSP_IMSC(pl022->virtbase));
1233 		writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1234 		writew((readw(SSP_CR1(pl022->virtbase)) &
1235 			(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
1236 		msg->state = STATE_ERROR;
1237 
1238 		/* Schedule message queue handler */
1239 		tasklet_schedule(&pl022->pump_transfers);
1240 		return IRQ_HANDLED;
1241 	}
1242 
1243 	readwriter(pl022);
1244 
1245 	if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
1246 		flag = 1;
1247 		/* Disable Transmit interrupt */
1248 		writew(readw(SSP_IMSC(pl022->virtbase)) &
1249 		       (~SSP_IMSC_MASK_TXIM),
1250 		       SSP_IMSC(pl022->virtbase));
1251 	}
1252 
1253 	/*
1254 	 * Since all transactions must write as much as shall be read,
1255 	 * we can conclude the entire transaction once RX is complete.
1256 	 * At this point, all TX will always be finished.
1257 	 */
1258 	if (pl022->rx >= pl022->rx_end) {
1259 		writew(DISABLE_ALL_INTERRUPTS,
1260 		       SSP_IMSC(pl022->virtbase));
1261 		writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
1262 		if (unlikely(pl022->rx > pl022->rx_end)) {
1263 			dev_warn(&pl022->adev->dev, "read %u surplus "
1264 				 "bytes (did you request an odd "
1265 				 "number of bytes on a 16bit bus?)\n",
1266 				 (u32) (pl022->rx - pl022->rx_end));
1267 		}
1268 		/* Update total bytes transferred */
1269 		msg->actual_length += pl022->cur_transfer->len;
1270 		if (pl022->cur_transfer->cs_change)
1271 			pl022->cur_chip->
1272 				cs_control(SSP_CHIP_DESELECT);
1273 		/* Move to next transfer */
1274 		msg->state = next_transfer(pl022);
1275 		tasklet_schedule(&pl022->pump_transfers);
1276 		return IRQ_HANDLED;
1277 	}
1278 
1279 	return IRQ_HANDLED;
1280 }
1281 
1282 /**
1283  * This sets up the pointers to memory for the next message to
1284  * send out on the SPI bus.
1285  */
1286 static int set_up_next_transfer(struct pl022 *pl022,
1287 				struct spi_transfer *transfer)
1288 {
1289 	int residue;
1290 
1291 	/* Sanity check the message for this bus width */
1292 	residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
1293 	if (unlikely(residue != 0)) {
1294 		dev_err(&pl022->adev->dev,
1295 			"message of %u bytes to transmit but the current "
1296 			"chip bus has a data width of %u bytes!\n",
1297 			pl022->cur_transfer->len,
1298 			pl022->cur_chip->n_bytes);
1299 		dev_err(&pl022->adev->dev, "skipping this message\n");
1300 		return -EIO;
1301 	}
1302 	pl022->tx = (void *)transfer->tx_buf;
1303 	pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
1304 	pl022->rx = (void *)transfer->rx_buf;
1305 	pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
1306 	pl022->write =
1307 	    pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
1308 	pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
1309 	return 0;
1310 }
1311 
1312 /**
1313  * pump_transfers - Tasklet function which schedules next transfer
1314  * when running in interrupt or DMA transfer mode.
1315  * @data: SSP driver private data structure
1316  *
1317  */
1318 static void pump_transfers(unsigned long data)
1319 {
1320 	struct pl022 *pl022 = (struct pl022 *) data;
1321 	struct spi_message *message = NULL;
1322 	struct spi_transfer *transfer = NULL;
1323 	struct spi_transfer *previous = NULL;
1324 
1325 	/* Get current state information */
1326 	message = pl022->cur_msg;
1327 	transfer = pl022->cur_transfer;
1328 
1329 	/* Handle for abort */
1330 	if (message->state == STATE_ERROR) {
1331 		message->status = -EIO;
1332 		giveback(pl022);
1333 		return;
1334 	}
1335 
1336 	/* Handle end of message */
1337 	if (message->state == STATE_DONE) {
1338 		message->status = 0;
1339 		giveback(pl022);
1340 		return;
1341 	}
1342 
1343 	/* Delay if requested at end of transfer before CS change */
1344 	if (message->state == STATE_RUNNING) {
1345 		previous = list_entry(transfer->transfer_list.prev,
1346 					struct spi_transfer,
1347 					transfer_list);
1348 		if (previous->delay_usecs)
1349 			/*
1350 			 * FIXME: This runs in interrupt context.
1351 			 * Is this really smart?
1352 			 */
1353 			udelay(previous->delay_usecs);
1354 
1355 		/* Drop chip select only if cs_change is requested */
1356 		if (previous->cs_change)
1357 			pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1358 	} else {
1359 		/* STATE_START */
1360 		message->state = STATE_RUNNING;
1361 	}
1362 
1363 	if (set_up_next_transfer(pl022, transfer)) {
1364 		message->state = STATE_ERROR;
1365 		message->status = -EIO;
1366 		giveback(pl022);
1367 		return;
1368 	}
1369 	/* Flush the FIFOs and let's go! */
1370 	flush(pl022);
1371 
1372 	if (pl022->cur_chip->enable_dma) {
1373 		if (configure_dma(pl022)) {
1374 			dev_dbg(&pl022->adev->dev,
1375 				"configuration of DMA failed, fall back to interrupt mode\n");
1376 			goto err_config_dma;
1377 		}
1378 		return;
1379 	}
1380 
1381 err_config_dma:
1382 	writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
1383 }
1384 
1385 static void do_interrupt_dma_transfer(struct pl022 *pl022)
1386 {
1387 	u32 irqflags = ENABLE_ALL_INTERRUPTS;
1388 
1389 	/* Enable target chip */
1390 	pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1391 	if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
1392 		/* Error path */
1393 		pl022->cur_msg->state = STATE_ERROR;
1394 		pl022->cur_msg->status = -EIO;
1395 		giveback(pl022);
1396 		return;
1397 	}
1398 	/* If we're using DMA, set up DMA here */
1399 	if (pl022->cur_chip->enable_dma) {
1400 		/* Configure DMA transfer */
1401 		if (configure_dma(pl022)) {
1402 			dev_dbg(&pl022->adev->dev,
1403 				"configuration of DMA failed, fall back to interrupt mode\n");
1404 			goto err_config_dma;
1405 		}
1406 		/* Disable interrupts in DMA mode, IRQ from DMA controller */
1407 		irqflags = DISABLE_ALL_INTERRUPTS;
1408 	}
1409 err_config_dma:
1410 	/* Enable SSP, turn on interrupts */
1411 	writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1412 	       SSP_CR1(pl022->virtbase));
1413 	writew(irqflags, SSP_IMSC(pl022->virtbase));
1414 }
1415 
1416 static void do_polling_transfer(struct pl022 *pl022)
1417 {
1418 	struct spi_message *message = NULL;
1419 	struct spi_transfer *transfer = NULL;
1420 	struct spi_transfer *previous = NULL;
1421 	struct chip_data *chip;
1422 	unsigned long time, timeout;
1423 
1424 	chip = pl022->cur_chip;
1425 	message = pl022->cur_msg;
1426 
1427 	while (message->state != STATE_DONE) {
1428 		/* Handle for abort */
1429 		if (message->state == STATE_ERROR)
1430 			break;
1431 		transfer = pl022->cur_transfer;
1432 
1433 		/* Delay if requested at end of transfer */
1434 		if (message->state == STATE_RUNNING) {
1435 			previous =
1436 			    list_entry(transfer->transfer_list.prev,
1437 				       struct spi_transfer, transfer_list);
1438 			if (previous->delay_usecs)
1439 				udelay(previous->delay_usecs);
1440 			if (previous->cs_change)
1441 				pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1442 		} else {
1443 			/* STATE_START */
1444 			message->state = STATE_RUNNING;
1445 			pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
1446 		}
1447 
1448 		/* Configuration Changing Per Transfer */
1449 		if (set_up_next_transfer(pl022, transfer)) {
1450 			/* Error path */
1451 			message->state = STATE_ERROR;
1452 			break;
1453 		}
1454 		/* Flush FIFOs and enable SSP */
1455 		flush(pl022);
1456 		writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
1457 		       SSP_CR1(pl022->virtbase));
1458 
1459 		dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
1460 
1461 		timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
1462 		while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
1463 			time = jiffies;
1464 			readwriter(pl022);
1465 			if (time_after(time, timeout)) {
1466 				dev_warn(&pl022->adev->dev,
1467 				"%s: timeout!\n", __func__);
1468 				message->state = STATE_ERROR;
1469 				goto out;
1470 			}
1471 			cpu_relax();
1472 		}
1473 
1474 		/* Update total byte transferred */
1475 		message->actual_length += pl022->cur_transfer->len;
1476 		if (pl022->cur_transfer->cs_change)
1477 			pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
1478 		/* Move to next transfer */
1479 		message->state = next_transfer(pl022);
1480 	}
1481 out:
1482 	/* Handle end of message */
1483 	if (message->state == STATE_DONE)
1484 		message->status = 0;
1485 	else
1486 		message->status = -EIO;
1487 
1488 	giveback(pl022);
1489 	return;
1490 }
1491 
1492 /**
1493  * pump_messages - Workqueue function which processes spi message queue
1494  * @data: pointer to private data of SSP driver
1495  *
1496  * This function checks if there is any spi message in the queue that
1497  * needs processing and delegate control to appropriate function
1498  * do_polling_transfer()/do_interrupt_dma_transfer()
1499  * based on the kind of the transfer
1500  *
1501  */
1502 static void pump_messages(struct work_struct *work)
1503 {
1504 	struct pl022 *pl022 =
1505 		container_of(work, struct pl022, pump_messages);
1506 	unsigned long flags;
1507 
1508 	/* Lock queue and check for queue work */
1509 	spin_lock_irqsave(&pl022->queue_lock, flags);
1510 	if (list_empty(&pl022->queue) || !pl022->running) {
1511 		pl022->busy = false;
1512 		spin_unlock_irqrestore(&pl022->queue_lock, flags);
1513 		return;
1514 	}
1515 	/* Make sure we are not already running a message */
1516 	if (pl022->cur_msg) {
1517 		spin_unlock_irqrestore(&pl022->queue_lock, flags);
1518 		return;
1519 	}
1520 	/* Extract head of queue */
1521 	pl022->cur_msg =
1522 	    list_entry(pl022->queue.next, struct spi_message, queue);
1523 
1524 	list_del_init(&pl022->cur_msg->queue);
1525 	pl022->busy = true;
1526 	spin_unlock_irqrestore(&pl022->queue_lock, flags);
1527 
1528 	/* Initial message state */
1529 	pl022->cur_msg->state = STATE_START;
1530 	pl022->cur_transfer = list_entry(pl022->cur_msg->transfers.next,
1531 					    struct spi_transfer, transfer_list);
1532 
1533 	/* Setup the SPI using the per chip configuration */
1534 	pl022->cur_chip = spi_get_ctldata(pl022->cur_msg->spi);
1535 	/*
1536 	 * We enable the core voltage and clocks here, then the clocks
1537 	 * and core will be disabled when giveback() is called in each method
1538 	 * (poll/interrupt/DMA)
1539 	 */
1540 	pm_runtime_get_sync(&pl022->adev->dev);
1541 	restore_state(pl022);
1542 	flush(pl022);
1543 
1544 	if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
1545 		do_polling_transfer(pl022);
1546 	else
1547 		do_interrupt_dma_transfer(pl022);
1548 }
1549 
1550 static int __init init_queue(struct pl022 *pl022)
1551 {
1552 	INIT_LIST_HEAD(&pl022->queue);
1553 	spin_lock_init(&pl022->queue_lock);
1554 
1555 	pl022->running = false;
1556 	pl022->busy = false;
1557 
1558 	tasklet_init(&pl022->pump_transfers, pump_transfers,
1559 			(unsigned long)pl022);
1560 
1561 	INIT_WORK(&pl022->pump_messages, pump_messages);
1562 	pl022->workqueue = create_singlethread_workqueue(
1563 					dev_name(pl022->master->dev.parent));
1564 	if (pl022->workqueue == NULL)
1565 		return -EBUSY;
1566 
1567 	return 0;
1568 }
1569 
1570 static int start_queue(struct pl022 *pl022)
1571 {
1572 	unsigned long flags;
1573 
1574 	spin_lock_irqsave(&pl022->queue_lock, flags);
1575 
1576 	if (pl022->running || pl022->busy) {
1577 		spin_unlock_irqrestore(&pl022->queue_lock, flags);
1578 		return -EBUSY;
1579 	}
1580 
1581 	pl022->running = true;
1582 	pl022->cur_msg = NULL;
1583 	pl022->cur_transfer = NULL;
1584 	pl022->cur_chip = NULL;
1585 	spin_unlock_irqrestore(&pl022->queue_lock, flags);
1586 
1587 	queue_work(pl022->workqueue, &pl022->pump_messages);
1588 
1589 	return 0;
1590 }
1591 
1592 static int stop_queue(struct pl022 *pl022)
1593 {
1594 	unsigned long flags;
1595 	unsigned limit = 500;
1596 	int status = 0;
1597 
1598 	spin_lock_irqsave(&pl022->queue_lock, flags);
1599 
1600 	/* This is a bit lame, but is optimized for the common execution path.
1601 	 * A wait_queue on the pl022->busy could be used, but then the common
1602 	 * execution path (pump_messages) would be required to call wake_up or
1603 	 * friends on every SPI message. Do this instead */
1604 	while ((!list_empty(&pl022->queue) || pl022->busy) && limit--) {
1605 		spin_unlock_irqrestore(&pl022->queue_lock, flags);
1606 		msleep(10);
1607 		spin_lock_irqsave(&pl022->queue_lock, flags);
1608 	}
1609 
1610 	if (!list_empty(&pl022->queue) || pl022->busy)
1611 		status = -EBUSY;
1612 	else
1613 		pl022->running = false;
1614 
1615 	spin_unlock_irqrestore(&pl022->queue_lock, flags);
1616 
1617 	return status;
1618 }
1619 
1620 static int destroy_queue(struct pl022 *pl022)
1621 {
1622 	int status;
1623 
1624 	status = stop_queue(pl022);
1625 	/* we are unloading the module or failing to load (only two calls
1626 	 * to this routine), and neither call can handle a return value.
1627 	 * However, destroy_workqueue calls flush_workqueue, and that will
1628 	 * block until all work is done.  If the reason that stop_queue
1629 	 * timed out is that the work will never finish, then it does no
1630 	 * good to call destroy_workqueue, so return anyway. */
1631 	if (status != 0)
1632 		return status;
1633 
1634 	destroy_workqueue(pl022->workqueue);
1635 
1636 	return 0;
1637 }
1638 
1639 static int verify_controller_parameters(struct pl022 *pl022,
1640 				struct pl022_config_chip const *chip_info)
1641 {
1642 	if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
1643 	    || (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
1644 		dev_err(&pl022->adev->dev,
1645 			"interface is configured incorrectly\n");
1646 		return -EINVAL;
1647 	}
1648 	if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
1649 	    (!pl022->vendor->unidir)) {
1650 		dev_err(&pl022->adev->dev,
1651 			"unidirectional mode not supported in this "
1652 			"hardware version\n");
1653 		return -EINVAL;
1654 	}
1655 	if ((chip_info->hierarchy != SSP_MASTER)
1656 	    && (chip_info->hierarchy != SSP_SLAVE)) {
1657 		dev_err(&pl022->adev->dev,
1658 			"hierarchy is configured incorrectly\n");
1659 		return -EINVAL;
1660 	}
1661 	if ((chip_info->com_mode != INTERRUPT_TRANSFER)
1662 	    && (chip_info->com_mode != DMA_TRANSFER)
1663 	    && (chip_info->com_mode != POLLING_TRANSFER)) {
1664 		dev_err(&pl022->adev->dev,
1665 			"Communication mode is configured incorrectly\n");
1666 		return -EINVAL;
1667 	}
1668 	switch (chip_info->rx_lev_trig) {
1669 	case SSP_RX_1_OR_MORE_ELEM:
1670 	case SSP_RX_4_OR_MORE_ELEM:
1671 	case SSP_RX_8_OR_MORE_ELEM:
1672 		/* These are always OK, all variants can handle this */
1673 		break;
1674 	case SSP_RX_16_OR_MORE_ELEM:
1675 		if (pl022->vendor->fifodepth < 16) {
1676 			dev_err(&pl022->adev->dev,
1677 			"RX FIFO Trigger Level is configured incorrectly\n");
1678 			return -EINVAL;
1679 		}
1680 		break;
1681 	case SSP_RX_32_OR_MORE_ELEM:
1682 		if (pl022->vendor->fifodepth < 32) {
1683 			dev_err(&pl022->adev->dev,
1684 			"RX FIFO Trigger Level is configured incorrectly\n");
1685 			return -EINVAL;
1686 		}
1687 		break;
1688 	default:
1689 		dev_err(&pl022->adev->dev,
1690 			"RX FIFO Trigger Level is configured incorrectly\n");
1691 		return -EINVAL;
1692 		break;
1693 	}
1694 	switch (chip_info->tx_lev_trig) {
1695 	case SSP_TX_1_OR_MORE_EMPTY_LOC:
1696 	case SSP_TX_4_OR_MORE_EMPTY_LOC:
1697 	case SSP_TX_8_OR_MORE_EMPTY_LOC:
1698 		/* These are always OK, all variants can handle this */
1699 		break;
1700 	case SSP_TX_16_OR_MORE_EMPTY_LOC:
1701 		if (pl022->vendor->fifodepth < 16) {
1702 			dev_err(&pl022->adev->dev,
1703 			"TX FIFO Trigger Level is configured incorrectly\n");
1704 			return -EINVAL;
1705 		}
1706 		break;
1707 	case SSP_TX_32_OR_MORE_EMPTY_LOC:
1708 		if (pl022->vendor->fifodepth < 32) {
1709 			dev_err(&pl022->adev->dev,
1710 			"TX FIFO Trigger Level is configured incorrectly\n");
1711 			return -EINVAL;
1712 		}
1713 		break;
1714 	default:
1715 		dev_err(&pl022->adev->dev,
1716 			"TX FIFO Trigger Level is configured incorrectly\n");
1717 		return -EINVAL;
1718 		break;
1719 	}
1720 	if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
1721 		if ((chip_info->ctrl_len < SSP_BITS_4)
1722 		    || (chip_info->ctrl_len > SSP_BITS_32)) {
1723 			dev_err(&pl022->adev->dev,
1724 				"CTRL LEN is configured incorrectly\n");
1725 			return -EINVAL;
1726 		}
1727 		if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
1728 		    && (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
1729 			dev_err(&pl022->adev->dev,
1730 				"Wait State is configured incorrectly\n");
1731 			return -EINVAL;
1732 		}
1733 		/* Half duplex is only available in the ST Micro version */
1734 		if (pl022->vendor->extended_cr) {
1735 			if ((chip_info->duplex !=
1736 			     SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1737 			    && (chip_info->duplex !=
1738 				SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
1739 				dev_err(&pl022->adev->dev,
1740 					"Microwire duplex mode is configured incorrectly\n");
1741 				return -EINVAL;
1742 			}
1743 		} else {
1744 			if (chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
1745 				dev_err(&pl022->adev->dev,
1746 					"Microwire half duplex mode requested,"
1747 					" but this is only available in the"
1748 					" ST version of PL022\n");
1749 			return -EINVAL;
1750 		}
1751 	}
1752 	return 0;
1753 }
1754 
1755 /**
1756  * pl022_transfer - transfer function registered to SPI master framework
1757  * @spi: spi device which is requesting transfer
1758  * @msg: spi message which is to handled is queued to driver queue
1759  *
1760  * This function is registered to the SPI framework for this SPI master
1761  * controller. It will queue the spi_message in the queue of driver if
1762  * the queue is not stopped and return.
1763  */
1764 static int pl022_transfer(struct spi_device *spi, struct spi_message *msg)
1765 {
1766 	struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1767 	unsigned long flags;
1768 
1769 	spin_lock_irqsave(&pl022->queue_lock, flags);
1770 
1771 	if (!pl022->running) {
1772 		spin_unlock_irqrestore(&pl022->queue_lock, flags);
1773 		return -ESHUTDOWN;
1774 	}
1775 	msg->actual_length = 0;
1776 	msg->status = -EINPROGRESS;
1777 	msg->state = STATE_START;
1778 
1779 	list_add_tail(&msg->queue, &pl022->queue);
1780 	if (pl022->running && !pl022->busy)
1781 		queue_work(pl022->workqueue, &pl022->pump_messages);
1782 
1783 	spin_unlock_irqrestore(&pl022->queue_lock, flags);
1784 	return 0;
1785 }
1786 
1787 static inline u32 spi_rate(u32 rate, u16 cpsdvsr, u16 scr)
1788 {
1789 	return rate / (cpsdvsr * (1 + scr));
1790 }
1791 
1792 static int calculate_effective_freq(struct pl022 *pl022, int freq, struct
1793 				    ssp_clock_params * clk_freq)
1794 {
1795 	/* Lets calculate the frequency parameters */
1796 	u16 cpsdvsr = CPSDVR_MIN, scr = SCR_MIN;
1797 	u32 rate, max_tclk, min_tclk, best_freq = 0, best_cpsdvsr = 0,
1798 		best_scr = 0, tmp, found = 0;
1799 
1800 	rate = clk_get_rate(pl022->clk);
1801 	/* cpsdvscr = 2 & scr 0 */
1802 	max_tclk = spi_rate(rate, CPSDVR_MIN, SCR_MIN);
1803 	/* cpsdvsr = 254 & scr = 255 */
1804 	min_tclk = spi_rate(rate, CPSDVR_MAX, SCR_MAX);
1805 
1806 	if (!((freq <= max_tclk) && (freq >= min_tclk))) {
1807 		dev_err(&pl022->adev->dev,
1808 			"controller data is incorrect: out of range frequency");
1809 		return -EINVAL;
1810 	}
1811 
1812 	/*
1813 	 * best_freq will give closest possible available rate (<= requested
1814 	 * freq) for all values of scr & cpsdvsr.
1815 	 */
1816 	while ((cpsdvsr <= CPSDVR_MAX) && !found) {
1817 		while (scr <= SCR_MAX) {
1818 			tmp = spi_rate(rate, cpsdvsr, scr);
1819 
1820 			if (tmp > freq)
1821 				scr++;
1822 			/*
1823 			 * If found exact value, update and break.
1824 			 * If found more closer value, update and continue.
1825 			 */
1826 			else if ((tmp == freq) || (tmp > best_freq)) {
1827 				best_freq = tmp;
1828 				best_cpsdvsr = cpsdvsr;
1829 				best_scr = scr;
1830 
1831 				if (tmp == freq)
1832 					break;
1833 			}
1834 			scr++;
1835 		}
1836 		cpsdvsr += 2;
1837 		scr = SCR_MIN;
1838 	}
1839 
1840 	clk_freq->cpsdvsr = (u8) (best_cpsdvsr & 0xFF);
1841 	clk_freq->scr = (u8) (best_scr & 0xFF);
1842 	dev_dbg(&pl022->adev->dev,
1843 		"SSP Target Frequency is: %u, Effective Frequency is %u\n",
1844 		freq, best_freq);
1845 	dev_dbg(&pl022->adev->dev, "SSP cpsdvsr = %d, scr = %d\n",
1846 		clk_freq->cpsdvsr, clk_freq->scr);
1847 
1848 	return 0;
1849 }
1850 
1851 /*
1852  * A piece of default chip info unless the platform
1853  * supplies it.
1854  */
1855 static const struct pl022_config_chip pl022_default_chip_info = {
1856 	.com_mode = POLLING_TRANSFER,
1857 	.iface = SSP_INTERFACE_MOTOROLA_SPI,
1858 	.hierarchy = SSP_SLAVE,
1859 	.slave_tx_disable = DO_NOT_DRIVE_TX,
1860 	.rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
1861 	.tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
1862 	.ctrl_len = SSP_BITS_8,
1863 	.wait_state = SSP_MWIRE_WAIT_ZERO,
1864 	.duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
1865 	.cs_control = null_cs_control,
1866 };
1867 
1868 /**
1869  * pl022_setup - setup function registered to SPI master framework
1870  * @spi: spi device which is requesting setup
1871  *
1872  * This function is registered to the SPI framework for this SPI master
1873  * controller. If it is the first time when setup is called by this device,
1874  * this function will initialize the runtime state for this chip and save
1875  * the same in the device structure. Else it will update the runtime info
1876  * with the updated chip info. Nothing is really being written to the
1877  * controller hardware here, that is not done until the actual transfer
1878  * commence.
1879  */
1880 static int pl022_setup(struct spi_device *spi)
1881 {
1882 	struct pl022_config_chip const *chip_info;
1883 	struct chip_data *chip;
1884 	struct ssp_clock_params clk_freq = {0, };
1885 	int status = 0;
1886 	struct pl022 *pl022 = spi_master_get_devdata(spi->master);
1887 	unsigned int bits = spi->bits_per_word;
1888 	u32 tmp;
1889 
1890 	if (!spi->max_speed_hz)
1891 		return -EINVAL;
1892 
1893 	/* Get controller_state if one is supplied */
1894 	chip = spi_get_ctldata(spi);
1895 
1896 	if (chip == NULL) {
1897 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1898 		if (!chip) {
1899 			dev_err(&spi->dev,
1900 				"cannot allocate controller state\n");
1901 			return -ENOMEM;
1902 		}
1903 		dev_dbg(&spi->dev,
1904 			"allocated memory for controller's runtime state\n");
1905 	}
1906 
1907 	/* Get controller data if one is supplied */
1908 	chip_info = spi->controller_data;
1909 
1910 	if (chip_info == NULL) {
1911 		chip_info = &pl022_default_chip_info;
1912 		/* spi_board_info.controller_data not is supplied */
1913 		dev_dbg(&spi->dev,
1914 			"using default controller_data settings\n");
1915 	} else
1916 		dev_dbg(&spi->dev,
1917 			"using user supplied controller_data settings\n");
1918 
1919 	/*
1920 	 * We can override with custom divisors, else we use the board
1921 	 * frequency setting
1922 	 */
1923 	if ((0 == chip_info->clk_freq.cpsdvsr)
1924 	    && (0 == chip_info->clk_freq.scr)) {
1925 		status = calculate_effective_freq(pl022,
1926 						  spi->max_speed_hz,
1927 						  &clk_freq);
1928 		if (status < 0)
1929 			goto err_config_params;
1930 	} else {
1931 		memcpy(&clk_freq, &chip_info->clk_freq, sizeof(clk_freq));
1932 		if ((clk_freq.cpsdvsr % 2) != 0)
1933 			clk_freq.cpsdvsr =
1934 				clk_freq.cpsdvsr - 1;
1935 	}
1936 	if ((clk_freq.cpsdvsr < CPSDVR_MIN)
1937 	    || (clk_freq.cpsdvsr > CPSDVR_MAX)) {
1938 		status = -EINVAL;
1939 		dev_err(&spi->dev,
1940 			"cpsdvsr is configured incorrectly\n");
1941 		goto err_config_params;
1942 	}
1943 
1944 	status = verify_controller_parameters(pl022, chip_info);
1945 	if (status) {
1946 		dev_err(&spi->dev, "controller data is incorrect");
1947 		goto err_config_params;
1948 	}
1949 
1950 	pl022->rx_lev_trig = chip_info->rx_lev_trig;
1951 	pl022->tx_lev_trig = chip_info->tx_lev_trig;
1952 
1953 	/* Now set controller state based on controller data */
1954 	chip->xfer_type = chip_info->com_mode;
1955 	if (!chip_info->cs_control) {
1956 		chip->cs_control = null_cs_control;
1957 		dev_warn(&spi->dev,
1958 			 "chip select function is NULL for this chip\n");
1959 	} else
1960 		chip->cs_control = chip_info->cs_control;
1961 
1962 	if (bits <= 3) {
1963 		/* PL022 doesn't support less than 4-bits */
1964 		status = -ENOTSUPP;
1965 		goto err_config_params;
1966 	} else if (bits <= 8) {
1967 		dev_dbg(&spi->dev, "4 <= n <=8 bits per word\n");
1968 		chip->n_bytes = 1;
1969 		chip->read = READING_U8;
1970 		chip->write = WRITING_U8;
1971 	} else if (bits <= 16) {
1972 		dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
1973 		chip->n_bytes = 2;
1974 		chip->read = READING_U16;
1975 		chip->write = WRITING_U16;
1976 	} else {
1977 		if (pl022->vendor->max_bpw >= 32) {
1978 			dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
1979 			chip->n_bytes = 4;
1980 			chip->read = READING_U32;
1981 			chip->write = WRITING_U32;
1982 		} else {
1983 			dev_err(&spi->dev,
1984 				"illegal data size for this controller!\n");
1985 			dev_err(&spi->dev,
1986 				"a standard pl022 can only handle "
1987 				"1 <= n <= 16 bit words\n");
1988 			status = -ENOTSUPP;
1989 			goto err_config_params;
1990 		}
1991 	}
1992 
1993 	/* Now Initialize all register settings required for this chip */
1994 	chip->cr0 = 0;
1995 	chip->cr1 = 0;
1996 	chip->dmacr = 0;
1997 	chip->cpsr = 0;
1998 	if ((chip_info->com_mode == DMA_TRANSFER)
1999 	    && ((pl022->master_info)->enable_dma)) {
2000 		chip->enable_dma = true;
2001 		dev_dbg(&spi->dev, "DMA mode set in controller state\n");
2002 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
2003 			       SSP_DMACR_MASK_RXDMAE, 0);
2004 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
2005 			       SSP_DMACR_MASK_TXDMAE, 1);
2006 	} else {
2007 		chip->enable_dma = false;
2008 		dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
2009 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
2010 			       SSP_DMACR_MASK_RXDMAE, 0);
2011 		SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
2012 			       SSP_DMACR_MASK_TXDMAE, 1);
2013 	}
2014 
2015 	chip->cpsr = clk_freq.cpsdvsr;
2016 
2017 	/* Special setup for the ST micro extended control registers */
2018 	if (pl022->vendor->extended_cr) {
2019 		u32 etx;
2020 
2021 		if (pl022->vendor->pl023) {
2022 			/* These bits are only in the PL023 */
2023 			SSP_WRITE_BITS(chip->cr1, chip_info->clkdelay,
2024 				       SSP_CR1_MASK_FBCLKDEL_ST, 13);
2025 		} else {
2026 			/* These bits are in the PL022 but not PL023 */
2027 			SSP_WRITE_BITS(chip->cr0, chip_info->duplex,
2028 				       SSP_CR0_MASK_HALFDUP_ST, 5);
2029 			SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len,
2030 				       SSP_CR0_MASK_CSS_ST, 16);
2031 			SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2032 				       SSP_CR0_MASK_FRF_ST, 21);
2033 			SSP_WRITE_BITS(chip->cr1, chip_info->wait_state,
2034 				       SSP_CR1_MASK_MWAIT_ST, 6);
2035 		}
2036 		SSP_WRITE_BITS(chip->cr0, bits - 1,
2037 			       SSP_CR0_MASK_DSS_ST, 0);
2038 
2039 		if (spi->mode & SPI_LSB_FIRST) {
2040 			tmp = SSP_RX_LSB;
2041 			etx = SSP_TX_LSB;
2042 		} else {
2043 			tmp = SSP_RX_MSB;
2044 			etx = SSP_TX_MSB;
2045 		}
2046 		SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_RENDN_ST, 4);
2047 		SSP_WRITE_BITS(chip->cr1, etx, SSP_CR1_MASK_TENDN_ST, 5);
2048 		SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig,
2049 			       SSP_CR1_MASK_RXIFLSEL_ST, 7);
2050 		SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig,
2051 			       SSP_CR1_MASK_TXIFLSEL_ST, 10);
2052 	} else {
2053 		SSP_WRITE_BITS(chip->cr0, bits - 1,
2054 			       SSP_CR0_MASK_DSS, 0);
2055 		SSP_WRITE_BITS(chip->cr0, chip_info->iface,
2056 			       SSP_CR0_MASK_FRF, 4);
2057 	}
2058 
2059 	/* Stuff that is common for all versions */
2060 	if (spi->mode & SPI_CPOL)
2061 		tmp = SSP_CLK_POL_IDLE_HIGH;
2062 	else
2063 		tmp = SSP_CLK_POL_IDLE_LOW;
2064 	SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPO, 6);
2065 
2066 	if (spi->mode & SPI_CPHA)
2067 		tmp = SSP_CLK_SECOND_EDGE;
2068 	else
2069 		tmp = SSP_CLK_FIRST_EDGE;
2070 	SSP_WRITE_BITS(chip->cr0, tmp, SSP_CR0_MASK_SPH, 7);
2071 
2072 	SSP_WRITE_BITS(chip->cr0, clk_freq.scr, SSP_CR0_MASK_SCR, 8);
2073 	/* Loopback is available on all versions except PL023 */
2074 	if (pl022->vendor->loopback) {
2075 		if (spi->mode & SPI_LOOP)
2076 			tmp = LOOPBACK_ENABLED;
2077 		else
2078 			tmp = LOOPBACK_DISABLED;
2079 		SSP_WRITE_BITS(chip->cr1, tmp, SSP_CR1_MASK_LBM, 0);
2080 	}
2081 	SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
2082 	SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
2083 	SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD,
2084 		3);
2085 
2086 	/* Save controller_state */
2087 	spi_set_ctldata(spi, chip);
2088 	return status;
2089  err_config_params:
2090 	spi_set_ctldata(spi, NULL);
2091 	kfree(chip);
2092 	return status;
2093 }
2094 
2095 /**
2096  * pl022_cleanup - cleanup function registered to SPI master framework
2097  * @spi: spi device which is requesting cleanup
2098  *
2099  * This function is registered to the SPI framework for this SPI master
2100  * controller. It will free the runtime state of chip.
2101  */
2102 static void pl022_cleanup(struct spi_device *spi)
2103 {
2104 	struct chip_data *chip = spi_get_ctldata(spi);
2105 
2106 	spi_set_ctldata(spi, NULL);
2107 	kfree(chip);
2108 }
2109 
2110 static int __devinit
2111 pl022_probe(struct amba_device *adev, const struct amba_id *id)
2112 {
2113 	struct device *dev = &adev->dev;
2114 	struct pl022_ssp_controller *platform_info = adev->dev.platform_data;
2115 	struct spi_master *master;
2116 	struct pl022 *pl022 = NULL;	/*Data for this driver */
2117 	int status = 0;
2118 
2119 	dev_info(&adev->dev,
2120 		 "ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
2121 	if (platform_info == NULL) {
2122 		dev_err(&adev->dev, "probe - no platform data supplied\n");
2123 		status = -ENODEV;
2124 		goto err_no_pdata;
2125 	}
2126 
2127 	/* Allocate master with space for data */
2128 	master = spi_alloc_master(dev, sizeof(struct pl022));
2129 	if (master == NULL) {
2130 		dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
2131 		status = -ENOMEM;
2132 		goto err_no_master;
2133 	}
2134 
2135 	pl022 = spi_master_get_devdata(master);
2136 	pl022->master = master;
2137 	pl022->master_info = platform_info;
2138 	pl022->adev = adev;
2139 	pl022->vendor = id->data;
2140 
2141 	/*
2142 	 * Bus Number Which has been Assigned to this SSP controller
2143 	 * on this board
2144 	 */
2145 	master->bus_num = platform_info->bus_id;
2146 	master->num_chipselect = platform_info->num_chipselect;
2147 	master->cleanup = pl022_cleanup;
2148 	master->setup = pl022_setup;
2149 	master->transfer = pl022_transfer;
2150 
2151 	/*
2152 	 * Supports mode 0-3, loopback, and active low CS. Transfers are
2153 	 * always MS bit first on the original pl022.
2154 	 */
2155 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
2156 	if (pl022->vendor->extended_cr)
2157 		master->mode_bits |= SPI_LSB_FIRST;
2158 
2159 	dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
2160 
2161 	status = amba_request_regions(adev, NULL);
2162 	if (status)
2163 		goto err_no_ioregion;
2164 
2165 	pl022->phybase = adev->res.start;
2166 	pl022->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
2167 	if (pl022->virtbase == NULL) {
2168 		status = -ENOMEM;
2169 		goto err_no_ioremap;
2170 	}
2171 	printk(KERN_INFO "pl022: mapped registers from 0x%08x to %p\n",
2172 	       adev->res.start, pl022->virtbase);
2173 
2174 	pl022->clk = clk_get(&adev->dev, NULL);
2175 	if (IS_ERR(pl022->clk)) {
2176 		status = PTR_ERR(pl022->clk);
2177 		dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
2178 		goto err_no_clk;
2179 	}
2180 
2181 	status = clk_prepare(pl022->clk);
2182 	if (status) {
2183 		dev_err(&adev->dev, "could not prepare SSP/SPI bus clock\n");
2184 		goto  err_clk_prep;
2185 	}
2186 
2187 	/* Disable SSP */
2188 	writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
2189 	       SSP_CR1(pl022->virtbase));
2190 	load_ssp_default_config(pl022);
2191 
2192 	status = request_irq(adev->irq[0], pl022_interrupt_handler, 0, "pl022",
2193 			     pl022);
2194 	if (status < 0) {
2195 		dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
2196 		goto err_no_irq;
2197 	}
2198 
2199 	/* Get DMA channels */
2200 	if (platform_info->enable_dma) {
2201 		status = pl022_dma_probe(pl022);
2202 		if (status != 0)
2203 			platform_info->enable_dma = 0;
2204 	}
2205 
2206 	/* Initialize and start queue */
2207 	status = init_queue(pl022);
2208 	if (status != 0) {
2209 		dev_err(&adev->dev, "probe - problem initializing queue\n");
2210 		goto err_init_queue;
2211 	}
2212 	status = start_queue(pl022);
2213 	if (status != 0) {
2214 		dev_err(&adev->dev, "probe - problem starting queue\n");
2215 		goto err_start_queue;
2216 	}
2217 	/* Register with the SPI framework */
2218 	amba_set_drvdata(adev, pl022);
2219 	status = spi_register_master(master);
2220 	if (status != 0) {
2221 		dev_err(&adev->dev,
2222 			"probe - problem registering spi master\n");
2223 		goto err_spi_register;
2224 	}
2225 	dev_dbg(dev, "probe succeeded\n");
2226 
2227 	/* let runtime pm put suspend */
2228 	pm_runtime_put(dev);
2229 	return 0;
2230 
2231  err_spi_register:
2232  err_start_queue:
2233  err_init_queue:
2234 	destroy_queue(pl022);
2235 	if (platform_info->enable_dma)
2236 		pl022_dma_remove(pl022);
2237 
2238 	free_irq(adev->irq[0], pl022);
2239  err_no_irq:
2240 	clk_unprepare(pl022->clk);
2241  err_clk_prep:
2242 	clk_put(pl022->clk);
2243  err_no_clk:
2244 	iounmap(pl022->virtbase);
2245  err_no_ioremap:
2246 	amba_release_regions(adev);
2247  err_no_ioregion:
2248 	spi_master_put(master);
2249  err_no_master:
2250  err_no_pdata:
2251 	return status;
2252 }
2253 
2254 static int __devexit
2255 pl022_remove(struct amba_device *adev)
2256 {
2257 	struct pl022 *pl022 = amba_get_drvdata(adev);
2258 
2259 	if (!pl022)
2260 		return 0;
2261 
2262 	/*
2263 	 * undo pm_runtime_put() in probe.  I assume that we're not
2264 	 * accessing the primecell here.
2265 	 */
2266 	pm_runtime_get_noresume(&adev->dev);
2267 
2268 	/* Remove the queue */
2269 	if (destroy_queue(pl022) != 0)
2270 		dev_err(&adev->dev, "queue remove failed\n");
2271 	load_ssp_default_config(pl022);
2272 	if (pl022->master_info->enable_dma)
2273 		pl022_dma_remove(pl022);
2274 
2275 	free_irq(adev->irq[0], pl022);
2276 	clk_disable(pl022->clk);
2277 	clk_unprepare(pl022->clk);
2278 	clk_put(pl022->clk);
2279 	iounmap(pl022->virtbase);
2280 	amba_release_regions(adev);
2281 	tasklet_disable(&pl022->pump_transfers);
2282 	spi_unregister_master(pl022->master);
2283 	spi_master_put(pl022->master);
2284 	amba_set_drvdata(adev, NULL);
2285 	return 0;
2286 }
2287 
2288 #ifdef CONFIG_SUSPEND
2289 static int pl022_suspend(struct device *dev)
2290 {
2291 	struct pl022 *pl022 = dev_get_drvdata(dev);
2292 	int status = 0;
2293 
2294 	status = stop_queue(pl022);
2295 	if (status) {
2296 		dev_warn(dev, "suspend cannot stop queue\n");
2297 		return status;
2298 	}
2299 
2300 	amba_vcore_enable(pl022->adev);
2301 	amba_pclk_enable(pl022->adev);
2302 	load_ssp_default_config(pl022);
2303 	amba_pclk_disable(pl022->adev);
2304 	amba_vcore_disable(pl022->adev);
2305 	dev_dbg(dev, "suspended\n");
2306 	return 0;
2307 }
2308 
2309 static int pl022_resume(struct device *dev)
2310 {
2311 	struct pl022 *pl022 = dev_get_drvdata(dev);
2312 	int status = 0;
2313 
2314 	/* Start the queue running */
2315 	status = start_queue(pl022);
2316 	if (status)
2317 		dev_err(dev, "problem starting queue (%d)\n", status);
2318 	else
2319 		dev_dbg(dev, "resumed\n");
2320 
2321 	return status;
2322 }
2323 #endif	/* CONFIG_PM */
2324 
2325 #ifdef CONFIG_PM_RUNTIME
2326 static int pl022_runtime_suspend(struct device *dev)
2327 {
2328 	struct pl022 *pl022 = dev_get_drvdata(dev);
2329 
2330 	clk_disable(pl022->clk);
2331 	amba_vcore_disable(pl022->adev);
2332 
2333 	return 0;
2334 }
2335 
2336 static int pl022_runtime_resume(struct device *dev)
2337 {
2338 	struct pl022 *pl022 = dev_get_drvdata(dev);
2339 
2340 	amba_vcore_enable(pl022->adev);
2341 	clk_enable(pl022->clk);
2342 
2343 	return 0;
2344 }
2345 #endif
2346 
2347 static const struct dev_pm_ops pl022_dev_pm_ops = {
2348 	SET_SYSTEM_SLEEP_PM_OPS(pl022_suspend, pl022_resume)
2349 	SET_RUNTIME_PM_OPS(pl022_runtime_suspend, pl022_runtime_resume, NULL)
2350 };
2351 
2352 static struct vendor_data vendor_arm = {
2353 	.fifodepth = 8,
2354 	.max_bpw = 16,
2355 	.unidir = false,
2356 	.extended_cr = false,
2357 	.pl023 = false,
2358 	.loopback = true,
2359 };
2360 
2361 static struct vendor_data vendor_st = {
2362 	.fifodepth = 32,
2363 	.max_bpw = 32,
2364 	.unidir = false,
2365 	.extended_cr = true,
2366 	.pl023 = false,
2367 	.loopback = true,
2368 };
2369 
2370 static struct vendor_data vendor_st_pl023 = {
2371 	.fifodepth = 32,
2372 	.max_bpw = 32,
2373 	.unidir = false,
2374 	.extended_cr = true,
2375 	.pl023 = true,
2376 	.loopback = false,
2377 };
2378 
2379 static struct vendor_data vendor_db5500_pl023 = {
2380 	.fifodepth = 32,
2381 	.max_bpw = 32,
2382 	.unidir = false,
2383 	.extended_cr = true,
2384 	.pl023 = true,
2385 	.loopback = true,
2386 };
2387 
2388 static struct amba_id pl022_ids[] = {
2389 	{
2390 		/*
2391 		 * ARM PL022 variant, this has a 16bit wide
2392 		 * and 8 locations deep TX/RX FIFO
2393 		 */
2394 		.id	= 0x00041022,
2395 		.mask	= 0x000fffff,
2396 		.data	= &vendor_arm,
2397 	},
2398 	{
2399 		/*
2400 		 * ST Micro derivative, this has 32bit wide
2401 		 * and 32 locations deep TX/RX FIFO
2402 		 */
2403 		.id	= 0x01080022,
2404 		.mask	= 0xffffffff,
2405 		.data	= &vendor_st,
2406 	},
2407 	{
2408 		/*
2409 		 * ST-Ericsson derivative "PL023" (this is not
2410 		 * an official ARM number), this is a PL022 SSP block
2411 		 * stripped to SPI mode only, it has 32bit wide
2412 		 * and 32 locations deep TX/RX FIFO but no extended
2413 		 * CR0/CR1 register
2414 		 */
2415 		.id	= 0x00080023,
2416 		.mask	= 0xffffffff,
2417 		.data	= &vendor_st_pl023,
2418 	},
2419 	{
2420 		.id	= 0x10080023,
2421 		.mask	= 0xffffffff,
2422 		.data	= &vendor_db5500_pl023,
2423 	},
2424 	{ 0, 0 },
2425 };
2426 
2427 static struct amba_driver pl022_driver = {
2428 	.drv = {
2429 		.name	= "ssp-pl022",
2430 		.pm	= &pl022_dev_pm_ops,
2431 	},
2432 	.id_table	= pl022_ids,
2433 	.probe		= pl022_probe,
2434 	.remove		= __devexit_p(pl022_remove),
2435 };
2436 
2437 static int __init pl022_init(void)
2438 {
2439 	return amba_driver_register(&pl022_driver);
2440 }
2441 subsys_initcall(pl022_init);
2442 
2443 static void __exit pl022_exit(void)
2444 {
2445 	amba_driver_unregister(&pl022_driver);
2446 }
2447 module_exit(pl022_exit);
2448 
2449 MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
2450 MODULE_DESCRIPTION("PL022 SSP Controller Driver");
2451 MODULE_LICENSE("GPL");
2452