1 /*
2  * SPI bus driver for the Topcliff PCH used by Intel SoCs
3  *
4  * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
18  */
19 
20 #include <linux/delay.h>
21 #include <linux/pci.h>
22 #include <linux/wait.h>
23 #include <linux/spi/spi.h>
24 #include <linux/interrupt.h>
25 #include <linux/sched.h>
26 #include <linux/spi/spidev.h>
27 #include <linux/module.h>
28 #include <linux/device.h>
29 #include <linux/platform_device.h>
30 
31 #include <linux/dmaengine.h>
32 #include <linux/pch_dma.h>
33 
34 /* Register offsets */
35 #define PCH_SPCR		0x00	/* SPI control register */
36 #define PCH_SPBRR		0x04	/* SPI baud rate register */
37 #define PCH_SPSR		0x08	/* SPI status register */
38 #define PCH_SPDWR		0x0C	/* SPI write data register */
39 #define PCH_SPDRR		0x10	/* SPI read data register */
40 #define PCH_SSNXCR		0x18	/* SSN Expand Control Register */
41 #define PCH_SRST		0x1C	/* SPI reset register */
42 #define PCH_ADDRESS_SIZE	0x20
43 
44 #define PCH_SPSR_TFD		0x000007C0
45 #define PCH_SPSR_RFD		0x0000F800
46 
47 #define PCH_READABLE(x)		(((x) & PCH_SPSR_RFD)>>11)
48 #define PCH_WRITABLE(x)		(((x) & PCH_SPSR_TFD)>>6)
49 
50 #define PCH_RX_THOLD		7
51 #define PCH_RX_THOLD_MAX	15
52 
53 #define PCH_TX_THOLD		2
54 
55 #define PCH_MAX_BAUDRATE	5000000
56 #define PCH_MAX_FIFO_DEPTH	16
57 
58 #define STATUS_RUNNING		1
59 #define STATUS_EXITING		2
60 #define PCH_SLEEP_TIME		10
61 
62 #define SSN_LOW			0x02U
63 #define SSN_HIGH		0x03U
64 #define SSN_NO_CONTROL		0x00U
65 #define PCH_MAX_CS		0xFF
66 #define PCI_DEVICE_ID_GE_SPI	0x8816
67 
68 #define SPCR_SPE_BIT		(1 << 0)
69 #define SPCR_MSTR_BIT		(1 << 1)
70 #define SPCR_LSBF_BIT		(1 << 4)
71 #define SPCR_CPHA_BIT		(1 << 5)
72 #define SPCR_CPOL_BIT		(1 << 6)
73 #define SPCR_TFIE_BIT		(1 << 8)
74 #define SPCR_RFIE_BIT		(1 << 9)
75 #define SPCR_FIE_BIT		(1 << 10)
76 #define SPCR_ORIE_BIT		(1 << 11)
77 #define SPCR_MDFIE_BIT		(1 << 12)
78 #define SPCR_FICLR_BIT		(1 << 24)
79 #define SPSR_TFI_BIT		(1 << 0)
80 #define SPSR_RFI_BIT		(1 << 1)
81 #define SPSR_FI_BIT		(1 << 2)
82 #define SPSR_ORF_BIT		(1 << 3)
83 #define SPBRR_SIZE_BIT		(1 << 10)
84 
85 #define PCH_ALL			(SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\
86 				SPCR_ORIE_BIT|SPCR_MDFIE_BIT)
87 
88 #define SPCR_RFIC_FIELD		20
89 #define SPCR_TFIC_FIELD		16
90 
91 #define MASK_SPBRR_SPBR_BITS	((1 << 10) - 1)
92 #define MASK_RFIC_SPCR_BITS	(0xf << SPCR_RFIC_FIELD)
93 #define MASK_TFIC_SPCR_BITS	(0xf << SPCR_TFIC_FIELD)
94 
95 #define PCH_CLOCK_HZ		50000000
96 #define PCH_MAX_SPBR		1023
97 
98 /* Definition for ML7213 by OKI SEMICONDUCTOR */
99 #define PCI_VENDOR_ID_ROHM		0x10DB
100 #define PCI_DEVICE_ID_ML7213_SPI	0x802c
101 #define PCI_DEVICE_ID_ML7223_SPI	0x800F
102 
103 /*
104  * Set the number of SPI instance max
105  * Intel EG20T PCH :		1ch
106  * OKI SEMICONDUCTOR ML7213 IOH :	2ch
107  * OKI SEMICONDUCTOR ML7223 IOH :	1ch
108 */
109 #define PCH_SPI_MAX_DEV			2
110 
111 #define PCH_BUF_SIZE		4096
112 #define PCH_DMA_TRANS_SIZE	12
113 
114 static int use_dma = 1;
115 
116 struct pch_spi_dma_ctrl {
117 	struct dma_async_tx_descriptor	*desc_tx;
118 	struct dma_async_tx_descriptor	*desc_rx;
119 	struct pch_dma_slave		param_tx;
120 	struct pch_dma_slave		param_rx;
121 	struct dma_chan		*chan_tx;
122 	struct dma_chan		*chan_rx;
123 	struct scatterlist		*sg_tx_p;
124 	struct scatterlist		*sg_rx_p;
125 	struct scatterlist		sg_tx;
126 	struct scatterlist		sg_rx;
127 	int				nent;
128 	void				*tx_buf_virt;
129 	void				*rx_buf_virt;
130 	dma_addr_t			tx_buf_dma;
131 	dma_addr_t			rx_buf_dma;
132 };
133 /**
134  * struct pch_spi_data - Holds the SPI channel specific details
135  * @io_remap_addr:		The remapped PCI base address
136  * @master:			Pointer to the SPI master structure
137  * @work:			Reference to work queue handler
138  * @wk:				Workqueue for carrying out execution of the
139  *				requests
140  * @wait:			Wait queue for waking up upon receiving an
141  *				interrupt.
142  * @transfer_complete:		Status of SPI Transfer
143  * @bcurrent_msg_processing:	Status flag for message processing
144  * @lock:			Lock for protecting this structure
145  * @queue:			SPI Message queue
146  * @status:			Status of the SPI driver
147  * @bpw_len:			Length of data to be transferred in bits per
148  *				word
149  * @transfer_active:		Flag showing active transfer
150  * @tx_index:			Transmit data count; for bookkeeping during
151  *				transfer
152  * @rx_index:			Receive data count; for bookkeeping during
153  *				transfer
154  * @tx_buff:			Buffer for data to be transmitted
155  * @rx_index:			Buffer for Received data
156  * @n_curnt_chip:		The chip number that this SPI driver currently
157  *				operates on
158  * @current_chip:		Reference to the current chip that this SPI
159  *				driver currently operates on
160  * @current_msg:		The current message that this SPI driver is
161  *				handling
162  * @cur_trans:			The current transfer that this SPI driver is
163  *				handling
164  * @board_dat:			Reference to the SPI device data structure
165  * @plat_dev:			platform_device structure
166  * @ch:				SPI channel number
167  * @irq_reg_sts:		Status of IRQ registration
168  */
169 struct pch_spi_data {
170 	void __iomem *io_remap_addr;
171 	unsigned long io_base_addr;
172 	struct spi_master *master;
173 	struct work_struct work;
174 	struct workqueue_struct *wk;
175 	wait_queue_head_t wait;
176 	u8 transfer_complete;
177 	u8 bcurrent_msg_processing;
178 	spinlock_t lock;
179 	struct list_head queue;
180 	u8 status;
181 	u32 bpw_len;
182 	u8 transfer_active;
183 	u32 tx_index;
184 	u32 rx_index;
185 	u16 *pkt_tx_buff;
186 	u16 *pkt_rx_buff;
187 	u8 n_curnt_chip;
188 	struct spi_device *current_chip;
189 	struct spi_message *current_msg;
190 	struct spi_transfer *cur_trans;
191 	struct pch_spi_board_data *board_dat;
192 	struct platform_device	*plat_dev;
193 	int ch;
194 	struct pch_spi_dma_ctrl dma;
195 	int use_dma;
196 	u8 irq_reg_sts;
197 };
198 
199 /**
200  * struct pch_spi_board_data - Holds the SPI device specific details
201  * @pdev:		Pointer to the PCI device
202  * @suspend_sts:	Status of suspend
203  * @num:		The number of SPI device instance
204  */
205 struct pch_spi_board_data {
206 	struct pci_dev *pdev;
207 	u8 suspend_sts;
208 	int num;
209 };
210 
211 struct pch_pd_dev_save {
212 	int num;
213 	struct platform_device *pd_save[PCH_SPI_MAX_DEV];
214 	struct pch_spi_board_data *board_dat;
215 };
216 
217 static struct pci_device_id pch_spi_pcidev_id[] = {
218 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_GE_SPI),    1, },
219 	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_SPI), 2, },
220 	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_SPI), 1, },
221 	{ }
222 };
223 
224 /**
225  * pch_spi_writereg() - Performs  register writes
226  * @master:	Pointer to struct spi_master.
227  * @idx:	Register offset.
228  * @val:	Value to be written to register.
229  */
230 static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val)
231 {
232 	struct pch_spi_data *data = spi_master_get_devdata(master);
233 	iowrite32(val, (data->io_remap_addr + idx));
234 }
235 
236 /**
237  * pch_spi_readreg() - Performs register reads
238  * @master:	Pointer to struct spi_master.
239  * @idx:	Register offset.
240  */
241 static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
242 {
243 	struct pch_spi_data *data = spi_master_get_devdata(master);
244 	return ioread32(data->io_remap_addr + idx);
245 }
246 
247 static inline void pch_spi_setclr_reg(struct spi_master *master, int idx,
248 				      u32 set, u32 clr)
249 {
250 	u32 tmp = pch_spi_readreg(master, idx);
251 	tmp = (tmp & ~clr) | set;
252 	pch_spi_writereg(master, idx, tmp);
253 }
254 
255 static void pch_spi_set_master_mode(struct spi_master *master)
256 {
257 	pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0);
258 }
259 
260 /**
261  * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
262  * @master:	Pointer to struct spi_master.
263  */
264 static void pch_spi_clear_fifo(struct spi_master *master)
265 {
266 	pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0);
267 	pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT);
268 }
269 
270 static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
271 				void __iomem *io_remap_addr)
272 {
273 	u32 n_read, tx_index, rx_index, bpw_len;
274 	u16 *pkt_rx_buffer, *pkt_tx_buff;
275 	int read_cnt;
276 	u32 reg_spcr_val;
277 	void __iomem *spsr;
278 	void __iomem *spdrr;
279 	void __iomem *spdwr;
280 
281 	spsr = io_remap_addr + PCH_SPSR;
282 	iowrite32(reg_spsr_val, spsr);
283 
284 	if (data->transfer_active) {
285 		rx_index = data->rx_index;
286 		tx_index = data->tx_index;
287 		bpw_len = data->bpw_len;
288 		pkt_rx_buffer = data->pkt_rx_buff;
289 		pkt_tx_buff = data->pkt_tx_buff;
290 
291 		spdrr = io_remap_addr + PCH_SPDRR;
292 		spdwr = io_remap_addr + PCH_SPDWR;
293 
294 		n_read = PCH_READABLE(reg_spsr_val);
295 
296 		for (read_cnt = 0; (read_cnt < n_read); read_cnt++) {
297 			pkt_rx_buffer[rx_index++] = ioread32(spdrr);
298 			if (tx_index < bpw_len)
299 				iowrite32(pkt_tx_buff[tx_index++], spdwr);
300 		}
301 
302 		/* disable RFI if not needed */
303 		if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
304 			reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
305 			reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
306 
307 			/* reset rx threshold */
308 			reg_spcr_val &= ~MASK_RFIC_SPCR_BITS;
309 			reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
310 
311 			iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR));
312 		}
313 
314 		/* update counts */
315 		data->tx_index = tx_index;
316 		data->rx_index = rx_index;
317 
318 	}
319 
320 	/* if transfer complete interrupt */
321 	if (reg_spsr_val & SPSR_FI_BIT) {
322 		if ((tx_index == bpw_len) && (rx_index == tx_index)) {
323 			/* disable interrupts */
324 			pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
325 
326 			/* transfer is completed;
327 			   inform pch_spi_process_messages */
328 			data->transfer_complete = true;
329 			data->transfer_active = false;
330 			wake_up(&data->wait);
331 		} else {
332 			dev_err(&data->master->dev,
333 				"%s : Transfer is not completed", __func__);
334 		}
335 	}
336 }
337 
338 /**
339  * pch_spi_handler() - Interrupt handler
340  * @irq:	The interrupt number.
341  * @dev_id:	Pointer to struct pch_spi_board_data.
342  */
343 static irqreturn_t pch_spi_handler(int irq, void *dev_id)
344 {
345 	u32 reg_spsr_val;
346 	void __iomem *spsr;
347 	void __iomem *io_remap_addr;
348 	irqreturn_t ret = IRQ_NONE;
349 	struct pch_spi_data *data = dev_id;
350 	struct pch_spi_board_data *board_dat = data->board_dat;
351 
352 	if (board_dat->suspend_sts) {
353 		dev_dbg(&board_dat->pdev->dev,
354 			"%s returning due to suspend\n", __func__);
355 		return IRQ_NONE;
356 	}
357 
358 	io_remap_addr = data->io_remap_addr;
359 	spsr = io_remap_addr + PCH_SPSR;
360 
361 	reg_spsr_val = ioread32(spsr);
362 
363 	if (reg_spsr_val & SPSR_ORF_BIT) {
364 		dev_err(&board_dat->pdev->dev, "%s Over run error\n", __func__);
365 		if (data->current_msg->complete != 0) {
366 			data->transfer_complete = true;
367 			data->current_msg->status = -EIO;
368 			data->current_msg->complete(data->current_msg->context);
369 			data->bcurrent_msg_processing = false;
370 			data->current_msg = NULL;
371 			data->cur_trans = NULL;
372 		}
373 	}
374 
375 	if (data->use_dma)
376 		return IRQ_NONE;
377 
378 	/* Check if the interrupt is for SPI device */
379 	if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
380 		pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
381 		ret = IRQ_HANDLED;
382 	}
383 
384 	dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
385 		__func__, ret);
386 
387 	return ret;
388 }
389 
390 /**
391  * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
392  * @master:	Pointer to struct spi_master.
393  * @speed_hz:	Baud rate.
394  */
395 static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
396 {
397 	u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
398 
399 	/* if baud rate is less than we can support limit it */
400 	if (n_spbr > PCH_MAX_SPBR)
401 		n_spbr = PCH_MAX_SPBR;
402 
403 	pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
404 }
405 
406 /**
407  * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
408  * @master:		Pointer to struct spi_master.
409  * @bits_per_word:	Bits per word for SPI transfer.
410  */
411 static void pch_spi_set_bits_per_word(struct spi_master *master,
412 				      u8 bits_per_word)
413 {
414 	if (bits_per_word == 8)
415 		pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
416 	else
417 		pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
418 }
419 
420 /**
421  * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
422  * @spi:	Pointer to struct spi_device.
423  */
424 static void pch_spi_setup_transfer(struct spi_device *spi)
425 {
426 	u32 flags = 0;
427 
428 	dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
429 		__func__, pch_spi_readreg(spi->master, PCH_SPBRR),
430 		spi->max_speed_hz);
431 	pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
432 
433 	/* set bits per word */
434 	pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
435 
436 	if (!(spi->mode & SPI_LSB_FIRST))
437 		flags |= SPCR_LSBF_BIT;
438 	if (spi->mode & SPI_CPOL)
439 		flags |= SPCR_CPOL_BIT;
440 	if (spi->mode & SPI_CPHA)
441 		flags |= SPCR_CPHA_BIT;
442 	pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
443 			   (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
444 
445 	/* Clear the FIFO by toggling  FICLR to 1 and back to 0 */
446 	pch_spi_clear_fifo(spi->master);
447 }
448 
449 /**
450  * pch_spi_reset() - Clears SPI registers
451  * @master:	Pointer to struct spi_master.
452  */
453 static void pch_spi_reset(struct spi_master *master)
454 {
455 	/* write 1 to reset SPI */
456 	pch_spi_writereg(master, PCH_SRST, 0x1);
457 
458 	/* clear reset */
459 	pch_spi_writereg(master, PCH_SRST, 0x0);
460 }
461 
462 static int pch_spi_setup(struct spi_device *pspi)
463 {
464 	/* check bits per word */
465 	if (pspi->bits_per_word == 0) {
466 		pspi->bits_per_word = 8;
467 		dev_dbg(&pspi->dev, "%s 8 bits per word\n", __func__);
468 	}
469 
470 	if ((pspi->bits_per_word != 8) && (pspi->bits_per_word != 16)) {
471 		dev_err(&pspi->dev, "%s Invalid bits per word\n", __func__);
472 		return -EINVAL;
473 	}
474 
475 	/* Check baud rate setting */
476 	/* if baud rate of chip is greater than
477 	   max we can support,return error */
478 	if ((pspi->max_speed_hz) > PCH_MAX_BAUDRATE)
479 		pspi->max_speed_hz = PCH_MAX_BAUDRATE;
480 
481 	dev_dbg(&pspi->dev, "%s MODE = %x\n", __func__,
482 		(pspi->mode) & (SPI_CPOL | SPI_CPHA));
483 
484 	return 0;
485 }
486 
487 static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
488 {
489 
490 	struct spi_transfer *transfer;
491 	struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
492 	int retval;
493 	unsigned long flags;
494 
495 	/* validate spi message and baud rate */
496 	if (unlikely(list_empty(&pmsg->transfers) == 1)) {
497 		dev_err(&pspi->dev, "%s list empty\n", __func__);
498 		retval = -EINVAL;
499 		goto err_out;
500 	}
501 
502 	if (unlikely(pspi->max_speed_hz == 0)) {
503 		dev_err(&pspi->dev, "%s pch_spi_tranfer maxspeed=%d\n",
504 			__func__, pspi->max_speed_hz);
505 		retval = -EINVAL;
506 		goto err_out;
507 	}
508 
509 	dev_dbg(&pspi->dev, "%s Transfer List not empty. "
510 		"Transfer Speed is set.\n", __func__);
511 
512 	spin_lock_irqsave(&data->lock, flags);
513 	/* validate Tx/Rx buffers and Transfer length */
514 	list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
515 		if (!transfer->tx_buf && !transfer->rx_buf) {
516 			dev_err(&pspi->dev,
517 				"%s Tx and Rx buffer NULL\n", __func__);
518 			retval = -EINVAL;
519 			goto err_return_spinlock;
520 		}
521 
522 		if (!transfer->len) {
523 			dev_err(&pspi->dev, "%s Transfer length invalid\n",
524 				__func__);
525 			retval = -EINVAL;
526 			goto err_return_spinlock;
527 		}
528 
529 		dev_dbg(&pspi->dev, "%s Tx/Rx buffer valid. Transfer length"
530 			" valid\n", __func__);
531 
532 		/* if baud rate has been specified validate the same */
533 		if (transfer->speed_hz > PCH_MAX_BAUDRATE)
534 			transfer->speed_hz = PCH_MAX_BAUDRATE;
535 
536 		/* if bits per word has been specified validate the same */
537 		if (transfer->bits_per_word) {
538 			if ((transfer->bits_per_word != 8)
539 			    && (transfer->bits_per_word != 16)) {
540 				retval = -EINVAL;
541 				dev_err(&pspi->dev,
542 					"%s Invalid bits per word\n", __func__);
543 				goto err_return_spinlock;
544 			}
545 		}
546 	}
547 	spin_unlock_irqrestore(&data->lock, flags);
548 
549 	/* We won't process any messages if we have been asked to terminate */
550 	if (data->status == STATUS_EXITING) {
551 		dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
552 		retval = -ESHUTDOWN;
553 		goto err_out;
554 	}
555 
556 	/* If suspended ,return -EINVAL */
557 	if (data->board_dat->suspend_sts) {
558 		dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
559 		retval = -EINVAL;
560 		goto err_out;
561 	}
562 
563 	/* set status of message */
564 	pmsg->actual_length = 0;
565 	dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
566 
567 	pmsg->status = -EINPROGRESS;
568 	spin_lock_irqsave(&data->lock, flags);
569 	/* add message to queue */
570 	list_add_tail(&pmsg->queue, &data->queue);
571 	spin_unlock_irqrestore(&data->lock, flags);
572 
573 	dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
574 
575 	/* schedule work queue to run */
576 	queue_work(data->wk, &data->work);
577 	dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
578 
579 	retval = 0;
580 
581 err_out:
582 	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
583 	return retval;
584 err_return_spinlock:
585 	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
586 	spin_unlock_irqrestore(&data->lock, flags);
587 	return retval;
588 }
589 
590 static inline void pch_spi_select_chip(struct pch_spi_data *data,
591 				       struct spi_device *pspi)
592 {
593 	if (data->current_chip != NULL) {
594 		if (pspi->chip_select != data->n_curnt_chip) {
595 			dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
596 			data->current_chip = NULL;
597 		}
598 	}
599 
600 	data->current_chip = pspi;
601 
602 	data->n_curnt_chip = data->current_chip->chip_select;
603 
604 	dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
605 	pch_spi_setup_transfer(pspi);
606 }
607 
608 static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
609 {
610 	int size;
611 	u32 n_writes;
612 	int j;
613 	struct spi_message *pmsg;
614 	const u8 *tx_buf;
615 	const u16 *tx_sbuf;
616 
617 	/* set baud rate if needed */
618 	if (data->cur_trans->speed_hz) {
619 		dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
620 		pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
621 	}
622 
623 	/* set bits per word if needed */
624 	if (data->cur_trans->bits_per_word &&
625 	    (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
626 		dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
627 		pch_spi_set_bits_per_word(data->master,
628 					  data->cur_trans->bits_per_word);
629 		*bpw = data->cur_trans->bits_per_word;
630 	} else {
631 		*bpw = data->current_msg->spi->bits_per_word;
632 	}
633 
634 	/* reset Tx/Rx index */
635 	data->tx_index = 0;
636 	data->rx_index = 0;
637 
638 	data->bpw_len = data->cur_trans->len / (*bpw / 8);
639 
640 	/* find alloc size */
641 	size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
642 
643 	/* allocate memory for pkt_tx_buff & pkt_rx_buffer */
644 	data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
645 	if (data->pkt_tx_buff != NULL) {
646 		data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
647 		if (!data->pkt_rx_buff)
648 			kfree(data->pkt_tx_buff);
649 	}
650 
651 	if (!data->pkt_rx_buff) {
652 		/* flush queue and set status of all transfers to -ENOMEM */
653 		dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__);
654 		list_for_each_entry(pmsg, data->queue.next, queue) {
655 			pmsg->status = -ENOMEM;
656 
657 			if (pmsg->complete != 0)
658 				pmsg->complete(pmsg->context);
659 
660 			/* delete from queue */
661 			list_del_init(&pmsg->queue);
662 		}
663 		return;
664 	}
665 
666 	/* copy Tx Data */
667 	if (data->cur_trans->tx_buf != NULL) {
668 		if (*bpw == 8) {
669 			tx_buf = data->cur_trans->tx_buf;
670 			for (j = 0; j < data->bpw_len; j++)
671 				data->pkt_tx_buff[j] = *tx_buf++;
672 		} else {
673 			tx_sbuf = data->cur_trans->tx_buf;
674 			for (j = 0; j < data->bpw_len; j++)
675 				data->pkt_tx_buff[j] = *tx_sbuf++;
676 		}
677 	}
678 
679 	/* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
680 	n_writes = data->bpw_len;
681 	if (n_writes > PCH_MAX_FIFO_DEPTH)
682 		n_writes = PCH_MAX_FIFO_DEPTH;
683 
684 	dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
685 		"0x2 to SSNXCR\n", __func__);
686 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
687 
688 	for (j = 0; j < n_writes; j++)
689 		pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
690 
691 	/* update tx_index */
692 	data->tx_index = j;
693 
694 	/* reset transfer complete flag */
695 	data->transfer_complete = false;
696 	data->transfer_active = true;
697 }
698 
699 static void pch_spi_nomore_transfer(struct pch_spi_data *data)
700 {
701 	struct spi_message *pmsg;
702 	dev_dbg(&data->master->dev, "%s called\n", __func__);
703 	/* Invoke complete callback
704 	 * [To the spi core..indicating end of transfer] */
705 	data->current_msg->status = 0;
706 
707 	if (data->current_msg->complete != 0) {
708 		dev_dbg(&data->master->dev,
709 			"%s:Invoking callback of SPI core\n", __func__);
710 		data->current_msg->complete(data->current_msg->context);
711 	}
712 
713 	/* update status in global variable */
714 	data->bcurrent_msg_processing = false;
715 
716 	dev_dbg(&data->master->dev,
717 		"%s:data->bcurrent_msg_processing = false\n", __func__);
718 
719 	data->current_msg = NULL;
720 	data->cur_trans = NULL;
721 
722 	/* check if we have items in list and not suspending
723 	 * return 1 if list empty */
724 	if ((list_empty(&data->queue) == 0) &&
725 	    (!data->board_dat->suspend_sts) &&
726 	    (data->status != STATUS_EXITING)) {
727 		/* We have some more work to do (either there is more tranint
728 		 * bpw;sfer requests in the current message or there are
729 		 *more messages)
730 		 */
731 		dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
732 		queue_work(data->wk, &data->work);
733 	} else if (data->board_dat->suspend_sts ||
734 		   data->status == STATUS_EXITING) {
735 		dev_dbg(&data->master->dev,
736 			"%s suspend/remove initiated, flushing queue\n",
737 			__func__);
738 		list_for_each_entry(pmsg, data->queue.next, queue) {
739 			pmsg->status = -EIO;
740 
741 			if (pmsg->complete)
742 				pmsg->complete(pmsg->context);
743 
744 			/* delete from queue */
745 			list_del_init(&pmsg->queue);
746 		}
747 	}
748 }
749 
750 static void pch_spi_set_ir(struct pch_spi_data *data)
751 {
752 	/* enable interrupts, set threshold, enable SPI */
753 	if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
754 		/* set receive threshold to PCH_RX_THOLD */
755 		pch_spi_setclr_reg(data->master, PCH_SPCR,
756 				   PCH_RX_THOLD << SPCR_RFIC_FIELD |
757 				   SPCR_FIE_BIT | SPCR_RFIE_BIT |
758 				   SPCR_ORIE_BIT | SPCR_SPE_BIT,
759 				   MASK_RFIC_SPCR_BITS | PCH_ALL);
760 	else
761 		/* set receive threshold to maximum */
762 		pch_spi_setclr_reg(data->master, PCH_SPCR,
763 				   PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
764 				   SPCR_FIE_BIT | SPCR_ORIE_BIT |
765 				   SPCR_SPE_BIT,
766 				   MASK_RFIC_SPCR_BITS | PCH_ALL);
767 
768 	/* Wait until the transfer completes; go to sleep after
769 				 initiating the transfer. */
770 	dev_dbg(&data->master->dev,
771 		"%s:waiting for transfer to get over\n", __func__);
772 
773 	wait_event_interruptible(data->wait, data->transfer_complete);
774 
775 	/* clear all interrupts */
776 	pch_spi_writereg(data->master, PCH_SPSR,
777 			 pch_spi_readreg(data->master, PCH_SPSR));
778 	/* Disable interrupts and SPI transfer */
779 	pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
780 	/* clear FIFO */
781 	pch_spi_clear_fifo(data->master);
782 }
783 
784 static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
785 {
786 	int j;
787 	u8 *rx_buf;
788 	u16 *rx_sbuf;
789 
790 	/* copy Rx Data */
791 	if (!data->cur_trans->rx_buf)
792 		return;
793 
794 	if (bpw == 8) {
795 		rx_buf = data->cur_trans->rx_buf;
796 		for (j = 0; j < data->bpw_len; j++)
797 			*rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
798 	} else {
799 		rx_sbuf = data->cur_trans->rx_buf;
800 		for (j = 0; j < data->bpw_len; j++)
801 			*rx_sbuf++ = data->pkt_rx_buff[j];
802 	}
803 }
804 
805 static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
806 {
807 	int j;
808 	u8 *rx_buf;
809 	u16 *rx_sbuf;
810 	const u8 *rx_dma_buf;
811 	const u16 *rx_dma_sbuf;
812 
813 	/* copy Rx Data */
814 	if (!data->cur_trans->rx_buf)
815 		return;
816 
817 	if (bpw == 8) {
818 		rx_buf = data->cur_trans->rx_buf;
819 		rx_dma_buf = data->dma.rx_buf_virt;
820 		for (j = 0; j < data->bpw_len; j++)
821 			*rx_buf++ = *rx_dma_buf++ & 0xFF;
822 	} else {
823 		rx_sbuf = data->cur_trans->rx_buf;
824 		rx_dma_sbuf = data->dma.rx_buf_virt;
825 		for (j = 0; j < data->bpw_len; j++)
826 			*rx_sbuf++ = *rx_dma_sbuf++;
827 	}
828 }
829 
830 static int pch_spi_start_transfer(struct pch_spi_data *data)
831 {
832 	struct pch_spi_dma_ctrl *dma;
833 	unsigned long flags;
834 	int rtn;
835 
836 	dma = &data->dma;
837 
838 	spin_lock_irqsave(&data->lock, flags);
839 
840 	/* disable interrupts, SPI set enable */
841 	pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
842 
843 	spin_unlock_irqrestore(&data->lock, flags);
844 
845 	/* Wait until the transfer completes; go to sleep after
846 				 initiating the transfer. */
847 	dev_dbg(&data->master->dev,
848 		"%s:waiting for transfer to get over\n", __func__);
849 	rtn = wait_event_interruptible_timeout(data->wait,
850 					       data->transfer_complete,
851 					       msecs_to_jiffies(2 * HZ));
852 
853 	dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
854 			    DMA_FROM_DEVICE);
855 
856 	dma_sync_sg_for_cpu(&data->master->dev, dma->sg_tx_p, dma->nent,
857 			    DMA_FROM_DEVICE);
858 	memset(data->dma.tx_buf_virt, 0, PAGE_SIZE);
859 
860 	async_tx_ack(dma->desc_rx);
861 	async_tx_ack(dma->desc_tx);
862 	kfree(dma->sg_tx_p);
863 	kfree(dma->sg_rx_p);
864 
865 	spin_lock_irqsave(&data->lock, flags);
866 
867 	/* clear fifo threshold, disable interrupts, disable SPI transfer */
868 	pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
869 			   MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
870 			   SPCR_SPE_BIT);
871 	/* clear all interrupts */
872 	pch_spi_writereg(data->master, PCH_SPSR,
873 			 pch_spi_readreg(data->master, PCH_SPSR));
874 	/* clear FIFO */
875 	pch_spi_clear_fifo(data->master);
876 
877 	spin_unlock_irqrestore(&data->lock, flags);
878 
879 	return rtn;
880 }
881 
882 static void pch_dma_rx_complete(void *arg)
883 {
884 	struct pch_spi_data *data = arg;
885 
886 	/* transfer is completed;inform pch_spi_process_messages_dma */
887 	data->transfer_complete = true;
888 	wake_up_interruptible(&data->wait);
889 }
890 
891 static bool pch_spi_filter(struct dma_chan *chan, void *slave)
892 {
893 	struct pch_dma_slave *param = slave;
894 
895 	if ((chan->chan_id == param->chan_id) &&
896 	    (param->dma_dev == chan->device->dev)) {
897 		chan->private = param;
898 		return true;
899 	} else {
900 		return false;
901 	}
902 }
903 
904 static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
905 {
906 	dma_cap_mask_t mask;
907 	struct dma_chan *chan;
908 	struct pci_dev *dma_dev;
909 	struct pch_dma_slave *param;
910 	struct pch_spi_dma_ctrl *dma;
911 	unsigned int width;
912 
913 	if (bpw == 8)
914 		width = PCH_DMA_WIDTH_1_BYTE;
915 	else
916 		width = PCH_DMA_WIDTH_2_BYTES;
917 
918 	dma = &data->dma;
919 	dma_cap_zero(mask);
920 	dma_cap_set(DMA_SLAVE, mask);
921 
922 	/* Get DMA's dev information */
923 	dma_dev = pci_get_bus_and_slot(2, PCI_DEVFN(12, 0));
924 
925 	/* Set Tx DMA */
926 	param = &dma->param_tx;
927 	param->dma_dev = &dma_dev->dev;
928 	param->chan_id = data->master->bus_num * 2; /* Tx = 0, 2 */
929 	param->tx_reg = data->io_base_addr + PCH_SPDWR;
930 	param->width = width;
931 	chan = dma_request_channel(mask, pch_spi_filter, param);
932 	if (!chan) {
933 		dev_err(&data->master->dev,
934 			"ERROR: dma_request_channel FAILS(Tx)\n");
935 		data->use_dma = 0;
936 		return;
937 	}
938 	dma->chan_tx = chan;
939 
940 	/* Set Rx DMA */
941 	param = &dma->param_rx;
942 	param->dma_dev = &dma_dev->dev;
943 	param->chan_id = data->master->bus_num * 2 + 1; /* Rx = Tx + 1 */
944 	param->rx_reg = data->io_base_addr + PCH_SPDRR;
945 	param->width = width;
946 	chan = dma_request_channel(mask, pch_spi_filter, param);
947 	if (!chan) {
948 		dev_err(&data->master->dev,
949 			"ERROR: dma_request_channel FAILS(Rx)\n");
950 		dma_release_channel(dma->chan_tx);
951 		dma->chan_tx = NULL;
952 		data->use_dma = 0;
953 		return;
954 	}
955 	dma->chan_rx = chan;
956 }
957 
958 static void pch_spi_release_dma(struct pch_spi_data *data)
959 {
960 	struct pch_spi_dma_ctrl *dma;
961 
962 	dma = &data->dma;
963 	if (dma->chan_tx) {
964 		dma_release_channel(dma->chan_tx);
965 		dma->chan_tx = NULL;
966 	}
967 	if (dma->chan_rx) {
968 		dma_release_channel(dma->chan_rx);
969 		dma->chan_rx = NULL;
970 	}
971 	return;
972 }
973 
974 static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
975 {
976 	const u8 *tx_buf;
977 	const u16 *tx_sbuf;
978 	u8 *tx_dma_buf;
979 	u16 *tx_dma_sbuf;
980 	struct scatterlist *sg;
981 	struct dma_async_tx_descriptor *desc_tx;
982 	struct dma_async_tx_descriptor *desc_rx;
983 	int num;
984 	int i;
985 	int size;
986 	int rem;
987 	unsigned long flags;
988 	struct pch_spi_dma_ctrl *dma;
989 
990 	dma = &data->dma;
991 
992 	/* set baud rate if needed */
993 	if (data->cur_trans->speed_hz) {
994 		dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
995 		spin_lock_irqsave(&data->lock, flags);
996 		pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
997 		spin_unlock_irqrestore(&data->lock, flags);
998 	}
999 
1000 	/* set bits per word if needed */
1001 	if (data->cur_trans->bits_per_word &&
1002 	    (data->current_msg->spi->bits_per_word !=
1003 	     data->cur_trans->bits_per_word)) {
1004 		dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
1005 		spin_lock_irqsave(&data->lock, flags);
1006 		pch_spi_set_bits_per_word(data->master,
1007 					  data->cur_trans->bits_per_word);
1008 		spin_unlock_irqrestore(&data->lock, flags);
1009 		*bpw = data->cur_trans->bits_per_word;
1010 	} else {
1011 		*bpw = data->current_msg->spi->bits_per_word;
1012 	}
1013 	data->bpw_len = data->cur_trans->len / (*bpw / 8);
1014 
1015 	/* copy Tx Data */
1016 	if (data->cur_trans->tx_buf != NULL) {
1017 		if (*bpw == 8) {
1018 			tx_buf = data->cur_trans->tx_buf;
1019 			tx_dma_buf = dma->tx_buf_virt;
1020 			for (i = 0; i < data->bpw_len; i++)
1021 				*tx_dma_buf++ = *tx_buf++;
1022 		} else {
1023 			tx_sbuf = data->cur_trans->tx_buf;
1024 			tx_dma_sbuf = dma->tx_buf_virt;
1025 			for (i = 0; i < data->bpw_len; i++)
1026 				*tx_dma_sbuf++ = *tx_sbuf++;
1027 		}
1028 	}
1029 	if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
1030 		num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
1031 		size = PCH_DMA_TRANS_SIZE;
1032 		rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
1033 	} else {
1034 		num = 1;
1035 		size = data->bpw_len;
1036 		rem = data->bpw_len;
1037 	}
1038 	dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
1039 		__func__, num, size, rem);
1040 	spin_lock_irqsave(&data->lock, flags);
1041 
1042 	/* set receive fifo threshold and transmit fifo threshold */
1043 	pch_spi_setclr_reg(data->master, PCH_SPCR,
1044 			   ((size - 1) << SPCR_RFIC_FIELD) |
1045 			   (PCH_TX_THOLD << SPCR_TFIC_FIELD),
1046 			   MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
1047 
1048 	spin_unlock_irqrestore(&data->lock, flags);
1049 
1050 	/* RX */
1051 	dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
1052 	sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
1053 	/* offset, length setting */
1054 	sg = dma->sg_rx_p;
1055 	for (i = 0; i < num; i++, sg++) {
1056 		if (i == (num - 2)) {
1057 			sg->offset = size * i;
1058 			sg->offset = sg->offset * (*bpw / 8);
1059 			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
1060 				    sg->offset);
1061 			sg_dma_len(sg) = rem;
1062 		} else if (i == (num - 1)) {
1063 			sg->offset = size * (i - 1) + rem;
1064 			sg->offset = sg->offset * (*bpw / 8);
1065 			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1066 				    sg->offset);
1067 			sg_dma_len(sg) = size;
1068 		} else {
1069 			sg->offset = size * i;
1070 			sg->offset = sg->offset * (*bpw / 8);
1071 			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1072 				    sg->offset);
1073 			sg_dma_len(sg) = size;
1074 		}
1075 		sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
1076 	}
1077 	sg = dma->sg_rx_p;
1078 	desc_rx = dma->chan_rx->device->device_prep_slave_sg(dma->chan_rx, sg,
1079 					num, DMA_FROM_DEVICE,
1080 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1081 	if (!desc_rx) {
1082 		dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
1083 			__func__);
1084 		return;
1085 	}
1086 	dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
1087 	desc_rx->callback = pch_dma_rx_complete;
1088 	desc_rx->callback_param = data;
1089 	dma->nent = num;
1090 	dma->desc_rx = desc_rx;
1091 
1092 	/* TX */
1093 	if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
1094 		num = data->bpw_len / PCH_DMA_TRANS_SIZE;
1095 		size = PCH_DMA_TRANS_SIZE;
1096 		rem = 16;
1097 	} else {
1098 		num = 1;
1099 		size = data->bpw_len;
1100 		rem = data->bpw_len;
1101 	}
1102 
1103 	dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
1104 	sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
1105 	/* offset, length setting */
1106 	sg = dma->sg_tx_p;
1107 	for (i = 0; i < num; i++, sg++) {
1108 		if (i == 0) {
1109 			sg->offset = 0;
1110 			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
1111 				    sg->offset);
1112 			sg_dma_len(sg) = rem;
1113 		} else {
1114 			sg->offset = rem + size * (i - 1);
1115 			sg->offset = sg->offset * (*bpw / 8);
1116 			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
1117 				    sg->offset);
1118 			sg_dma_len(sg) = size;
1119 		}
1120 		sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
1121 	}
1122 	sg = dma->sg_tx_p;
1123 	desc_tx = dma->chan_tx->device->device_prep_slave_sg(dma->chan_tx,
1124 					sg, num, DMA_TO_DEVICE,
1125 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1126 	if (!desc_tx) {
1127 		dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
1128 			__func__);
1129 		return;
1130 	}
1131 	dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
1132 	desc_tx->callback = NULL;
1133 	desc_tx->callback_param = data;
1134 	dma->nent = num;
1135 	dma->desc_tx = desc_tx;
1136 
1137 	dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
1138 		"0x2 to SSNXCR\n", __func__);
1139 
1140 	spin_lock_irqsave(&data->lock, flags);
1141 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
1142 	desc_rx->tx_submit(desc_rx);
1143 	desc_tx->tx_submit(desc_tx);
1144 	spin_unlock_irqrestore(&data->lock, flags);
1145 
1146 	/* reset transfer complete flag */
1147 	data->transfer_complete = false;
1148 }
1149 
1150 static void pch_spi_process_messages(struct work_struct *pwork)
1151 {
1152 	struct spi_message *pmsg;
1153 	struct pch_spi_data *data;
1154 	int bpw;
1155 
1156 	data = container_of(pwork, struct pch_spi_data, work);
1157 	dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
1158 
1159 	spin_lock(&data->lock);
1160 	/* check if suspend has been initiated;if yes flush queue */
1161 	if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
1162 		dev_dbg(&data->master->dev, "%s suspend/remove initiated,"
1163 			"flushing queue\n", __func__);
1164 		list_for_each_entry(pmsg, data->queue.next, queue) {
1165 			pmsg->status = -EIO;
1166 
1167 			if (pmsg->complete != 0) {
1168 				spin_unlock(&data->lock);
1169 				pmsg->complete(pmsg->context);
1170 				spin_lock(&data->lock);
1171 			}
1172 
1173 			/* delete from queue */
1174 			list_del_init(&pmsg->queue);
1175 		}
1176 
1177 		spin_unlock(&data->lock);
1178 		return;
1179 	}
1180 
1181 	data->bcurrent_msg_processing = true;
1182 	dev_dbg(&data->master->dev,
1183 		"%s Set data->bcurrent_msg_processing= true\n", __func__);
1184 
1185 	/* Get the message from the queue and delete it from there. */
1186 	data->current_msg = list_entry(data->queue.next, struct spi_message,
1187 					queue);
1188 
1189 	list_del_init(&data->current_msg->queue);
1190 
1191 	data->current_msg->status = 0;
1192 
1193 	pch_spi_select_chip(data, data->current_msg->spi);
1194 
1195 	spin_unlock(&data->lock);
1196 
1197 	if (data->use_dma)
1198 		pch_spi_request_dma(data,
1199 				    data->current_msg->spi->bits_per_word);
1200 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
1201 	do {
1202 		/* If we are already processing a message get the next
1203 		transfer structure from the message otherwise retrieve
1204 		the 1st transfer request from the message. */
1205 		spin_lock(&data->lock);
1206 		if (data->cur_trans == NULL) {
1207 			data->cur_trans =
1208 				list_entry(data->current_msg->transfers.next,
1209 					   struct spi_transfer, transfer_list);
1210 			dev_dbg(&data->master->dev, "%s "
1211 				":Getting 1st transfer message\n", __func__);
1212 		} else {
1213 			data->cur_trans =
1214 				list_entry(data->cur_trans->transfer_list.next,
1215 					   struct spi_transfer, transfer_list);
1216 			dev_dbg(&data->master->dev, "%s "
1217 				":Getting next transfer message\n", __func__);
1218 		}
1219 		spin_unlock(&data->lock);
1220 
1221 		if (data->use_dma) {
1222 			pch_spi_handle_dma(data, &bpw);
1223 			if (!pch_spi_start_transfer(data))
1224 				goto out;
1225 			pch_spi_copy_rx_data_for_dma(data, bpw);
1226 		} else {
1227 			pch_spi_set_tx(data, &bpw);
1228 			pch_spi_set_ir(data);
1229 			pch_spi_copy_rx_data(data, bpw);
1230 			kfree(data->pkt_rx_buff);
1231 			data->pkt_rx_buff = NULL;
1232 			kfree(data->pkt_tx_buff);
1233 			data->pkt_tx_buff = NULL;
1234 		}
1235 		/* increment message count */
1236 		data->current_msg->actual_length += data->cur_trans->len;
1237 
1238 		dev_dbg(&data->master->dev,
1239 			"%s:data->current_msg->actual_length=%d\n",
1240 			__func__, data->current_msg->actual_length);
1241 
1242 		/* check for delay */
1243 		if (data->cur_trans->delay_usecs) {
1244 			dev_dbg(&data->master->dev, "%s:"
1245 				"delay in usec=%d\n", __func__,
1246 				data->cur_trans->delay_usecs);
1247 			udelay(data->cur_trans->delay_usecs);
1248 		}
1249 
1250 		spin_lock(&data->lock);
1251 
1252 		/* No more transfer in this message. */
1253 		if ((data->cur_trans->transfer_list.next) ==
1254 		    &(data->current_msg->transfers)) {
1255 			pch_spi_nomore_transfer(data);
1256 		}
1257 
1258 		spin_unlock(&data->lock);
1259 
1260 	} while (data->cur_trans != NULL);
1261 
1262 out:
1263 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH);
1264 	if (data->use_dma)
1265 		pch_spi_release_dma(data);
1266 }
1267 
1268 static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
1269 				   struct pch_spi_data *data)
1270 {
1271 	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1272 
1273 	/* free workqueue */
1274 	if (data->wk != NULL) {
1275 		destroy_workqueue(data->wk);
1276 		data->wk = NULL;
1277 		dev_dbg(&board_dat->pdev->dev,
1278 			"%s destroy_workqueue invoked successfully\n",
1279 			__func__);
1280 	}
1281 }
1282 
1283 static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,
1284 				 struct pch_spi_data *data)
1285 {
1286 	int retval = 0;
1287 
1288 	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1289 
1290 	/* create workqueue */
1291 	data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
1292 	if (!data->wk) {
1293 		dev_err(&board_dat->pdev->dev,
1294 			"%s create_singlet hread_workqueue failed\n", __func__);
1295 		retval = -EBUSY;
1296 		goto err_return;
1297 	}
1298 
1299 	/* reset PCH SPI h/w */
1300 	pch_spi_reset(data->master);
1301 	dev_dbg(&board_dat->pdev->dev,
1302 		"%s pch_spi_reset invoked successfully\n", __func__);
1303 
1304 	dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
1305 
1306 err_return:
1307 	if (retval != 0) {
1308 		dev_err(&board_dat->pdev->dev,
1309 			"%s FAIL:invoking pch_spi_free_resources\n", __func__);
1310 		pch_spi_free_resources(board_dat, data);
1311 	}
1312 
1313 	dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
1314 
1315 	return retval;
1316 }
1317 
1318 static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
1319 			     struct pch_spi_data *data)
1320 {
1321 	struct pch_spi_dma_ctrl *dma;
1322 
1323 	dma = &data->dma;
1324 	if (dma->tx_buf_dma)
1325 		dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1326 				  dma->tx_buf_virt, dma->tx_buf_dma);
1327 	if (dma->rx_buf_dma)
1328 		dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1329 				  dma->rx_buf_virt, dma->rx_buf_dma);
1330 	return;
1331 }
1332 
1333 static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
1334 			      struct pch_spi_data *data)
1335 {
1336 	struct pch_spi_dma_ctrl *dma;
1337 
1338 	dma = &data->dma;
1339 	/* Get Consistent memory for Tx DMA */
1340 	dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1341 				PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
1342 	/* Get Consistent memory for Rx DMA */
1343 	dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1344 				PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
1345 }
1346 
1347 static int __devinit pch_spi_pd_probe(struct platform_device *plat_dev)
1348 {
1349 	int ret;
1350 	struct spi_master *master;
1351 	struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1352 	struct pch_spi_data *data;
1353 
1354 	dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
1355 
1356 	master = spi_alloc_master(&board_dat->pdev->dev,
1357 				  sizeof(struct pch_spi_data));
1358 	if (!master) {
1359 		dev_err(&plat_dev->dev, "spi_alloc_master[%d] failed.\n",
1360 			plat_dev->id);
1361 		return -ENOMEM;
1362 	}
1363 
1364 	data = spi_master_get_devdata(master);
1365 	data->master = master;
1366 
1367 	platform_set_drvdata(plat_dev, data);
1368 
1369 	/* baseaddress + address offset) */
1370 	data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
1371 					 PCH_ADDRESS_SIZE * plat_dev->id;
1372 	data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0) +
1373 					 PCH_ADDRESS_SIZE * plat_dev->id;
1374 	if (!data->io_remap_addr) {
1375 		dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
1376 		ret = -ENOMEM;
1377 		goto err_pci_iomap;
1378 	}
1379 
1380 	dev_dbg(&plat_dev->dev, "[ch%d] remap_addr=%p\n",
1381 		plat_dev->id, data->io_remap_addr);
1382 
1383 	/* initialize members of SPI master */
1384 	master->bus_num = -1;
1385 	master->num_chipselect = PCH_MAX_CS;
1386 	master->setup = pch_spi_setup;
1387 	master->transfer = pch_spi_transfer;
1388 
1389 	data->board_dat = board_dat;
1390 	data->plat_dev = plat_dev;
1391 	data->n_curnt_chip = 255;
1392 	data->status = STATUS_RUNNING;
1393 	data->ch = plat_dev->id;
1394 	data->use_dma = use_dma;
1395 
1396 	INIT_LIST_HEAD(&data->queue);
1397 	spin_lock_init(&data->lock);
1398 	INIT_WORK(&data->work, pch_spi_process_messages);
1399 	init_waitqueue_head(&data->wait);
1400 
1401 	ret = pch_spi_get_resources(board_dat, data);
1402 	if (ret) {
1403 		dev_err(&plat_dev->dev, "%s fail(retval=%d)\n", __func__, ret);
1404 		goto err_spi_get_resources;
1405 	}
1406 
1407 	ret = request_irq(board_dat->pdev->irq, pch_spi_handler,
1408 			  IRQF_SHARED, KBUILD_MODNAME, data);
1409 	if (ret) {
1410 		dev_err(&plat_dev->dev,
1411 			"%s request_irq failed\n", __func__);
1412 		goto err_request_irq;
1413 	}
1414 	data->irq_reg_sts = true;
1415 
1416 	pch_spi_set_master_mode(master);
1417 
1418 	ret = spi_register_master(master);
1419 	if (ret != 0) {
1420 		dev_err(&plat_dev->dev,
1421 			"%s spi_register_master FAILED\n", __func__);
1422 		goto err_spi_register_master;
1423 	}
1424 
1425 	if (use_dma) {
1426 		dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
1427 		pch_alloc_dma_buf(board_dat, data);
1428 	}
1429 
1430 	return 0;
1431 
1432 err_spi_register_master:
1433 	free_irq(board_dat->pdev->irq, board_dat);
1434 err_request_irq:
1435 	pch_spi_free_resources(board_dat, data);
1436 err_spi_get_resources:
1437 	pci_iounmap(board_dat->pdev, data->io_remap_addr);
1438 err_pci_iomap:
1439 	spi_master_put(master);
1440 
1441 	return ret;
1442 }
1443 
1444 static int __devexit pch_spi_pd_remove(struct platform_device *plat_dev)
1445 {
1446 	struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1447 	struct pch_spi_data *data = platform_get_drvdata(plat_dev);
1448 	int count;
1449 	unsigned long flags;
1450 
1451 	dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
1452 		__func__, plat_dev->id, board_dat->pdev->irq);
1453 
1454 	if (use_dma)
1455 		pch_free_dma_buf(board_dat, data);
1456 
1457 	/* check for any pending messages; no action is taken if the queue
1458 	 * is still full; but at least we tried.  Unload anyway */
1459 	count = 500;
1460 	spin_lock_irqsave(&data->lock, flags);
1461 	data->status = STATUS_EXITING;
1462 	while ((list_empty(&data->queue) == 0) && --count) {
1463 		dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
1464 			__func__);
1465 		spin_unlock_irqrestore(&data->lock, flags);
1466 		msleep(PCH_SLEEP_TIME);
1467 		spin_lock_irqsave(&data->lock, flags);
1468 	}
1469 	spin_unlock_irqrestore(&data->lock, flags);
1470 
1471 	pch_spi_free_resources(board_dat, data);
1472 	/* disable interrupts & free IRQ */
1473 	if (data->irq_reg_sts) {
1474 		/* disable interrupts */
1475 		pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1476 		data->irq_reg_sts = false;
1477 		free_irq(board_dat->pdev->irq, data);
1478 	}
1479 
1480 	pci_iounmap(board_dat->pdev, data->io_remap_addr);
1481 	spi_unregister_master(data->master);
1482 	spi_master_put(data->master);
1483 	platform_set_drvdata(plat_dev, NULL);
1484 
1485 	return 0;
1486 }
1487 #ifdef CONFIG_PM
1488 static int pch_spi_pd_suspend(struct platform_device *pd_dev,
1489 			      pm_message_t state)
1490 {
1491 	u8 count;
1492 	struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1493 	struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1494 
1495 	dev_dbg(&pd_dev->dev, "%s ENTRY\n", __func__);
1496 
1497 	if (!board_dat) {
1498 		dev_err(&pd_dev->dev,
1499 			"%s pci_get_drvdata returned NULL\n", __func__);
1500 		return -EFAULT;
1501 	}
1502 
1503 	/* check if the current message is processed:
1504 	   Only after thats done the transfer will be suspended */
1505 	count = 255;
1506 	while ((--count) > 0) {
1507 		if (!(data->bcurrent_msg_processing))
1508 			break;
1509 		msleep(PCH_SLEEP_TIME);
1510 	}
1511 
1512 	/* Free IRQ */
1513 	if (data->irq_reg_sts) {
1514 		/* disable all interrupts */
1515 		pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1516 		pch_spi_reset(data->master);
1517 		free_irq(board_dat->pdev->irq, data);
1518 
1519 		data->irq_reg_sts = false;
1520 		dev_dbg(&pd_dev->dev,
1521 			"%s free_irq invoked successfully.\n", __func__);
1522 	}
1523 
1524 	return 0;
1525 }
1526 
1527 static int pch_spi_pd_resume(struct platform_device *pd_dev)
1528 {
1529 	struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1530 	struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1531 	int retval;
1532 
1533 	if (!board_dat) {
1534 		dev_err(&pd_dev->dev,
1535 			"%s pci_get_drvdata returned NULL\n", __func__);
1536 		return -EFAULT;
1537 	}
1538 
1539 	if (!data->irq_reg_sts) {
1540 		/* register IRQ */
1541 		retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
1542 				     IRQF_SHARED, KBUILD_MODNAME, data);
1543 		if (retval < 0) {
1544 			dev_err(&pd_dev->dev,
1545 				"%s request_irq failed\n", __func__);
1546 			return retval;
1547 		}
1548 
1549 		/* reset PCH SPI h/w */
1550 		pch_spi_reset(data->master);
1551 		pch_spi_set_master_mode(data->master);
1552 		data->irq_reg_sts = true;
1553 	}
1554 	return 0;
1555 }
1556 #else
1557 #define pch_spi_pd_suspend NULL
1558 #define pch_spi_pd_resume NULL
1559 #endif
1560 
1561 static struct platform_driver pch_spi_pd_driver = {
1562 	.driver = {
1563 		.name = "pch-spi",
1564 		.owner = THIS_MODULE,
1565 	},
1566 	.probe = pch_spi_pd_probe,
1567 	.remove = __devexit_p(pch_spi_pd_remove),
1568 	.suspend = pch_spi_pd_suspend,
1569 	.resume = pch_spi_pd_resume
1570 };
1571 
1572 static int __devinit pch_spi_probe(struct pci_dev *pdev,
1573 				   const struct pci_device_id *id)
1574 {
1575 	struct pch_spi_board_data *board_dat;
1576 	struct platform_device *pd_dev = NULL;
1577 	int retval;
1578 	int i;
1579 	struct pch_pd_dev_save *pd_dev_save;
1580 
1581 	pd_dev_save = kzalloc(sizeof(struct pch_pd_dev_save), GFP_KERNEL);
1582 	if (!pd_dev_save) {
1583 		dev_err(&pdev->dev, "%s Can't allocate pd_dev_sav\n", __func__);
1584 		return -ENOMEM;
1585 	}
1586 
1587 	board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
1588 	if (!board_dat) {
1589 		dev_err(&pdev->dev, "%s Can't allocate board_dat\n", __func__);
1590 		retval = -ENOMEM;
1591 		goto err_no_mem;
1592 	}
1593 
1594 	retval = pci_request_regions(pdev, KBUILD_MODNAME);
1595 	if (retval) {
1596 		dev_err(&pdev->dev, "%s request_region failed\n", __func__);
1597 		goto pci_request_regions;
1598 	}
1599 
1600 	board_dat->pdev = pdev;
1601 	board_dat->num = id->driver_data;
1602 	pd_dev_save->num = id->driver_data;
1603 	pd_dev_save->board_dat = board_dat;
1604 
1605 	retval = pci_enable_device(pdev);
1606 	if (retval) {
1607 		dev_err(&pdev->dev, "%s pci_enable_device failed\n", __func__);
1608 		goto pci_enable_device;
1609 	}
1610 
1611 	for (i = 0; i < board_dat->num; i++) {
1612 		pd_dev = platform_device_alloc("pch-spi", i);
1613 		if (!pd_dev) {
1614 			dev_err(&pdev->dev, "platform_device_alloc failed\n");
1615 			goto err_platform_device;
1616 		}
1617 		pd_dev_save->pd_save[i] = pd_dev;
1618 		pd_dev->dev.parent = &pdev->dev;
1619 
1620 		retval = platform_device_add_data(pd_dev, board_dat,
1621 						  sizeof(*board_dat));
1622 		if (retval) {
1623 			dev_err(&pdev->dev,
1624 				"platform_device_add_data failed\n");
1625 			platform_device_put(pd_dev);
1626 			goto err_platform_device;
1627 		}
1628 
1629 		retval = platform_device_add(pd_dev);
1630 		if (retval) {
1631 			dev_err(&pdev->dev, "platform_device_add failed\n");
1632 			platform_device_put(pd_dev);
1633 			goto err_platform_device;
1634 		}
1635 	}
1636 
1637 	pci_set_drvdata(pdev, pd_dev_save);
1638 
1639 	return 0;
1640 
1641 err_platform_device:
1642 	pci_disable_device(pdev);
1643 pci_enable_device:
1644 	pci_release_regions(pdev);
1645 pci_request_regions:
1646 	kfree(board_dat);
1647 err_no_mem:
1648 	kfree(pd_dev_save);
1649 
1650 	return retval;
1651 }
1652 
1653 static void __devexit pch_spi_remove(struct pci_dev *pdev)
1654 {
1655 	int i;
1656 	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1657 
1658 	dev_dbg(&pdev->dev, "%s ENTRY:pdev=%p\n", __func__, pdev);
1659 
1660 	for (i = 0; i < pd_dev_save->num; i++)
1661 		platform_device_unregister(pd_dev_save->pd_save[i]);
1662 
1663 	pci_disable_device(pdev);
1664 	pci_release_regions(pdev);
1665 	kfree(pd_dev_save->board_dat);
1666 	kfree(pd_dev_save);
1667 }
1668 
1669 #ifdef CONFIG_PM
1670 static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
1671 {
1672 	int retval;
1673 	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1674 
1675 	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1676 
1677 	pd_dev_save->board_dat->suspend_sts = true;
1678 
1679 	/* save config space */
1680 	retval = pci_save_state(pdev);
1681 	if (retval == 0) {
1682 		pci_enable_wake(pdev, PCI_D3hot, 0);
1683 		pci_disable_device(pdev);
1684 		pci_set_power_state(pdev, PCI_D3hot);
1685 	} else {
1686 		dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
1687 	}
1688 
1689 	return retval;
1690 }
1691 
1692 static int pch_spi_resume(struct pci_dev *pdev)
1693 {
1694 	int retval;
1695 	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1696 	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1697 
1698 	pci_set_power_state(pdev, PCI_D0);
1699 	pci_restore_state(pdev);
1700 
1701 	retval = pci_enable_device(pdev);
1702 	if (retval < 0) {
1703 		dev_err(&pdev->dev,
1704 			"%s pci_enable_device failed\n", __func__);
1705 	} else {
1706 		pci_enable_wake(pdev, PCI_D3hot, 0);
1707 
1708 		/* set suspend status to false */
1709 		pd_dev_save->board_dat->suspend_sts = false;
1710 	}
1711 
1712 	return retval;
1713 }
1714 #else
1715 #define pch_spi_suspend NULL
1716 #define pch_spi_resume NULL
1717 
1718 #endif
1719 
1720 static struct pci_driver pch_spi_pcidev = {
1721 	.name = "pch_spi",
1722 	.id_table = pch_spi_pcidev_id,
1723 	.probe = pch_spi_probe,
1724 	.remove = pch_spi_remove,
1725 	.suspend = pch_spi_suspend,
1726 	.resume = pch_spi_resume,
1727 };
1728 
1729 static int __init pch_spi_init(void)
1730 {
1731 	int ret;
1732 	ret = platform_driver_register(&pch_spi_pd_driver);
1733 	if (ret)
1734 		return ret;
1735 
1736 	ret = pci_register_driver(&pch_spi_pcidev);
1737 	if (ret)
1738 		return ret;
1739 
1740 	return 0;
1741 }
1742 module_init(pch_spi_init);
1743 
1744 static void __exit pch_spi_exit(void)
1745 {
1746 	pci_unregister_driver(&pch_spi_pcidev);
1747 	platform_driver_unregister(&pch_spi_pd_driver);
1748 }
1749 module_exit(pch_spi_exit);
1750 
1751 module_param(use_dma, int, 0644);
1752 MODULE_PARM_DESC(use_dma,
1753 		 "to use DMA for data transfers pass 1 else 0; default 1");
1754 
1755 MODULE_LICENSE("GPL");
1756 MODULE_DESCRIPTION("Intel EG20T PCH/OKI SEMICONDUCTOR ML7xxx IOH SPI Driver");
1757