1 /*
2  * SPI bus driver for the Topcliff PCH used by Intel SoCs
3  *
4  * Copyright (C) 2011 LAPIS 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/ML7223/ML7831 by LAPIS 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 #define PCI_DEVICE_ID_ML7831_SPI	0x8816
103 
104 /*
105  * Set the number of SPI instance max
106  * Intel EG20T PCH :		1ch
107  * LAPIS Semiconductor ML7213 IOH :	2ch
108  * LAPIS Semiconductor ML7223 IOH :	1ch
109  * LAPIS Semiconductor ML7831 IOH :	1ch
110 */
111 #define PCH_SPI_MAX_DEV			2
112 
113 #define PCH_BUF_SIZE		4096
114 #define PCH_DMA_TRANS_SIZE	12
115 
116 static int use_dma = 1;
117 
118 struct pch_spi_dma_ctrl {
119 	struct dma_async_tx_descriptor	*desc_tx;
120 	struct dma_async_tx_descriptor	*desc_rx;
121 	struct pch_dma_slave		param_tx;
122 	struct pch_dma_slave		param_rx;
123 	struct dma_chan		*chan_tx;
124 	struct dma_chan		*chan_rx;
125 	struct scatterlist		*sg_tx_p;
126 	struct scatterlist		*sg_rx_p;
127 	struct scatterlist		sg_tx;
128 	struct scatterlist		sg_rx;
129 	int				nent;
130 	void				*tx_buf_virt;
131 	void				*rx_buf_virt;
132 	dma_addr_t			tx_buf_dma;
133 	dma_addr_t			rx_buf_dma;
134 };
135 /**
136  * struct pch_spi_data - Holds the SPI channel specific details
137  * @io_remap_addr:		The remapped PCI base address
138  * @master:			Pointer to the SPI master structure
139  * @work:			Reference to work queue handler
140  * @wk:				Workqueue for carrying out execution of the
141  *				requests
142  * @wait:			Wait queue for waking up upon receiving an
143  *				interrupt.
144  * @transfer_complete:		Status of SPI Transfer
145  * @bcurrent_msg_processing:	Status flag for message processing
146  * @lock:			Lock for protecting this structure
147  * @queue:			SPI Message queue
148  * @status:			Status of the SPI driver
149  * @bpw_len:			Length of data to be transferred in bits per
150  *				word
151  * @transfer_active:		Flag showing active transfer
152  * @tx_index:			Transmit data count; for bookkeeping during
153  *				transfer
154  * @rx_index:			Receive data count; for bookkeeping during
155  *				transfer
156  * @tx_buff:			Buffer for data to be transmitted
157  * @rx_index:			Buffer for Received data
158  * @n_curnt_chip:		The chip number that this SPI driver currently
159  *				operates on
160  * @current_chip:		Reference to the current chip that this SPI
161  *				driver currently operates on
162  * @current_msg:		The current message that this SPI driver is
163  *				handling
164  * @cur_trans:			The current transfer that this SPI driver is
165  *				handling
166  * @board_dat:			Reference to the SPI device data structure
167  * @plat_dev:			platform_device structure
168  * @ch:				SPI channel number
169  * @irq_reg_sts:		Status of IRQ registration
170  */
171 struct pch_spi_data {
172 	void __iomem *io_remap_addr;
173 	unsigned long io_base_addr;
174 	struct spi_master *master;
175 	struct work_struct work;
176 	struct workqueue_struct *wk;
177 	wait_queue_head_t wait;
178 	u8 transfer_complete;
179 	u8 bcurrent_msg_processing;
180 	spinlock_t lock;
181 	struct list_head queue;
182 	u8 status;
183 	u32 bpw_len;
184 	u8 transfer_active;
185 	u32 tx_index;
186 	u32 rx_index;
187 	u16 *pkt_tx_buff;
188 	u16 *pkt_rx_buff;
189 	u8 n_curnt_chip;
190 	struct spi_device *current_chip;
191 	struct spi_message *current_msg;
192 	struct spi_transfer *cur_trans;
193 	struct pch_spi_board_data *board_dat;
194 	struct platform_device	*plat_dev;
195 	int ch;
196 	struct pch_spi_dma_ctrl dma;
197 	int use_dma;
198 	u8 irq_reg_sts;
199 	int save_total_len;
200 };
201 
202 /**
203  * struct pch_spi_board_data - Holds the SPI device specific details
204  * @pdev:		Pointer to the PCI device
205  * @suspend_sts:	Status of suspend
206  * @num:		The number of SPI device instance
207  */
208 struct pch_spi_board_data {
209 	struct pci_dev *pdev;
210 	u8 suspend_sts;
211 	int num;
212 };
213 
214 struct pch_pd_dev_save {
215 	int num;
216 	struct platform_device *pd_save[PCH_SPI_MAX_DEV];
217 	struct pch_spi_board_data *board_dat;
218 };
219 
220 static const struct pci_device_id pch_spi_pcidev_id[] = {
221 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_GE_SPI),    1, },
222 	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_SPI), 2, },
223 	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_SPI), 1, },
224 	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_SPI), 1, },
225 	{ }
226 };
227 
228 /**
229  * pch_spi_writereg() - Performs  register writes
230  * @master:	Pointer to struct spi_master.
231  * @idx:	Register offset.
232  * @val:	Value to be written to register.
233  */
234 static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val)
235 {
236 	struct pch_spi_data *data = spi_master_get_devdata(master);
237 	iowrite32(val, (data->io_remap_addr + idx));
238 }
239 
240 /**
241  * pch_spi_readreg() - Performs register reads
242  * @master:	Pointer to struct spi_master.
243  * @idx:	Register offset.
244  */
245 static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
246 {
247 	struct pch_spi_data *data = spi_master_get_devdata(master);
248 	return ioread32(data->io_remap_addr + idx);
249 }
250 
251 static inline void pch_spi_setclr_reg(struct spi_master *master, int idx,
252 				      u32 set, u32 clr)
253 {
254 	u32 tmp = pch_spi_readreg(master, idx);
255 	tmp = (tmp & ~clr) | set;
256 	pch_spi_writereg(master, idx, tmp);
257 }
258 
259 static void pch_spi_set_master_mode(struct spi_master *master)
260 {
261 	pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0);
262 }
263 
264 /**
265  * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
266  * @master:	Pointer to struct spi_master.
267  */
268 static void pch_spi_clear_fifo(struct spi_master *master)
269 {
270 	pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0);
271 	pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT);
272 }
273 
274 static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
275 				void __iomem *io_remap_addr)
276 {
277 	u32 n_read, tx_index, rx_index, bpw_len;
278 	u16 *pkt_rx_buffer, *pkt_tx_buff;
279 	int read_cnt;
280 	u32 reg_spcr_val;
281 	void __iomem *spsr;
282 	void __iomem *spdrr;
283 	void __iomem *spdwr;
284 
285 	spsr = io_remap_addr + PCH_SPSR;
286 	iowrite32(reg_spsr_val, spsr);
287 
288 	if (data->transfer_active) {
289 		rx_index = data->rx_index;
290 		tx_index = data->tx_index;
291 		bpw_len = data->bpw_len;
292 		pkt_rx_buffer = data->pkt_rx_buff;
293 		pkt_tx_buff = data->pkt_tx_buff;
294 
295 		spdrr = io_remap_addr + PCH_SPDRR;
296 		spdwr = io_remap_addr + PCH_SPDWR;
297 
298 		n_read = PCH_READABLE(reg_spsr_val);
299 
300 		for (read_cnt = 0; (read_cnt < n_read); read_cnt++) {
301 			pkt_rx_buffer[rx_index++] = ioread32(spdrr);
302 			if (tx_index < bpw_len)
303 				iowrite32(pkt_tx_buff[tx_index++], spdwr);
304 		}
305 
306 		/* disable RFI if not needed */
307 		if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
308 			reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
309 			reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
310 
311 			/* reset rx threshold */
312 			reg_spcr_val &= ~MASK_RFIC_SPCR_BITS;
313 			reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
314 
315 			iowrite32(reg_spcr_val, (io_remap_addr + PCH_SPCR));
316 		}
317 
318 		/* update counts */
319 		data->tx_index = tx_index;
320 		data->rx_index = rx_index;
321 
322 		/* if transfer complete interrupt */
323 		if (reg_spsr_val & SPSR_FI_BIT) {
324 			if ((tx_index == bpw_len) && (rx_index == tx_index)) {
325 				/* disable interrupts */
326 				pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
327 						   PCH_ALL);
328 
329 				/* transfer is completed;
330 				   inform pch_spi_process_messages */
331 				data->transfer_complete = true;
332 				data->transfer_active = false;
333 				wake_up(&data->wait);
334 			} else {
335 				dev_err(&data->master->dev,
336 					"%s : Transfer is not completed",
337 					__func__);
338 			}
339 		}
340 	}
341 }
342 
343 /**
344  * pch_spi_handler() - Interrupt handler
345  * @irq:	The interrupt number.
346  * @dev_id:	Pointer to struct pch_spi_board_data.
347  */
348 static irqreturn_t pch_spi_handler(int irq, void *dev_id)
349 {
350 	u32 reg_spsr_val;
351 	void __iomem *spsr;
352 	void __iomem *io_remap_addr;
353 	irqreturn_t ret = IRQ_NONE;
354 	struct pch_spi_data *data = dev_id;
355 	struct pch_spi_board_data *board_dat = data->board_dat;
356 
357 	if (board_dat->suspend_sts) {
358 		dev_dbg(&board_dat->pdev->dev,
359 			"%s returning due to suspend\n", __func__);
360 		return IRQ_NONE;
361 	}
362 
363 	io_remap_addr = data->io_remap_addr;
364 	spsr = io_remap_addr + PCH_SPSR;
365 
366 	reg_spsr_val = ioread32(spsr);
367 
368 	if (reg_spsr_val & SPSR_ORF_BIT) {
369 		dev_err(&board_dat->pdev->dev, "%s Over run error\n", __func__);
370 		if (data->current_msg->complete) {
371 			data->transfer_complete = true;
372 			data->current_msg->status = -EIO;
373 			data->current_msg->complete(data->current_msg->context);
374 			data->bcurrent_msg_processing = false;
375 			data->current_msg = NULL;
376 			data->cur_trans = NULL;
377 		}
378 	}
379 
380 	if (data->use_dma)
381 		return IRQ_NONE;
382 
383 	/* Check if the interrupt is for SPI device */
384 	if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
385 		pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
386 		ret = IRQ_HANDLED;
387 	}
388 
389 	dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
390 		__func__, ret);
391 
392 	return ret;
393 }
394 
395 /**
396  * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
397  * @master:	Pointer to struct spi_master.
398  * @speed_hz:	Baud rate.
399  */
400 static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
401 {
402 	u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
403 
404 	/* if baud rate is less than we can support limit it */
405 	if (n_spbr > PCH_MAX_SPBR)
406 		n_spbr = PCH_MAX_SPBR;
407 
408 	pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
409 }
410 
411 /**
412  * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
413  * @master:		Pointer to struct spi_master.
414  * @bits_per_word:	Bits per word for SPI transfer.
415  */
416 static void pch_spi_set_bits_per_word(struct spi_master *master,
417 				      u8 bits_per_word)
418 {
419 	if (bits_per_word == 8)
420 		pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
421 	else
422 		pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
423 }
424 
425 /**
426  * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
427  * @spi:	Pointer to struct spi_device.
428  */
429 static void pch_spi_setup_transfer(struct spi_device *spi)
430 {
431 	u32 flags = 0;
432 
433 	dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
434 		__func__, pch_spi_readreg(spi->master, PCH_SPBRR),
435 		spi->max_speed_hz);
436 	pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
437 
438 	/* set bits per word */
439 	pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
440 
441 	if (!(spi->mode & SPI_LSB_FIRST))
442 		flags |= SPCR_LSBF_BIT;
443 	if (spi->mode & SPI_CPOL)
444 		flags |= SPCR_CPOL_BIT;
445 	if (spi->mode & SPI_CPHA)
446 		flags |= SPCR_CPHA_BIT;
447 	pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
448 			   (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
449 
450 	/* Clear the FIFO by toggling  FICLR to 1 and back to 0 */
451 	pch_spi_clear_fifo(spi->master);
452 }
453 
454 /**
455  * pch_spi_reset() - Clears SPI registers
456  * @master:	Pointer to struct spi_master.
457  */
458 static void pch_spi_reset(struct spi_master *master)
459 {
460 	/* write 1 to reset SPI */
461 	pch_spi_writereg(master, PCH_SRST, 0x1);
462 
463 	/* clear reset */
464 	pch_spi_writereg(master, PCH_SRST, 0x0);
465 }
466 
467 static int pch_spi_setup(struct spi_device *pspi)
468 {
469 	/* Check baud rate setting */
470 	/* if baud rate of chip is greater than
471 	   max we can support,return error */
472 	if ((pspi->max_speed_hz) > PCH_MAX_BAUDRATE)
473 		pspi->max_speed_hz = PCH_MAX_BAUDRATE;
474 
475 	dev_dbg(&pspi->dev, "%s MODE = %x\n", __func__,
476 		(pspi->mode) & (SPI_CPOL | SPI_CPHA));
477 
478 	return 0;
479 }
480 
481 static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
482 {
483 
484 	struct spi_transfer *transfer;
485 	struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
486 	int retval;
487 	unsigned long flags;
488 
489 	/* validate spi message and baud rate */
490 	if (unlikely(list_empty(&pmsg->transfers) == 1)) {
491 		dev_err(&pspi->dev, "%s list empty\n", __func__);
492 		retval = -EINVAL;
493 		goto err_out;
494 	}
495 
496 	if (unlikely(pspi->max_speed_hz == 0)) {
497 		dev_err(&pspi->dev, "%s pch_spi_transfer maxspeed=%d\n",
498 			__func__, pspi->max_speed_hz);
499 		retval = -EINVAL;
500 		goto err_out;
501 	}
502 
503 	dev_dbg(&pspi->dev,
504 		"%s Transfer List not empty. Transfer Speed is set.\n", __func__);
505 
506 	spin_lock_irqsave(&data->lock, flags);
507 	/* validate Tx/Rx buffers and Transfer length */
508 	list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
509 		if (!transfer->tx_buf && !transfer->rx_buf) {
510 			dev_err(&pspi->dev,
511 				"%s Tx and Rx buffer NULL\n", __func__);
512 			retval = -EINVAL;
513 			goto err_return_spinlock;
514 		}
515 
516 		if (!transfer->len) {
517 			dev_err(&pspi->dev, "%s Transfer length invalid\n",
518 				__func__);
519 			retval = -EINVAL;
520 			goto err_return_spinlock;
521 		}
522 
523 		dev_dbg(&pspi->dev,
524 			"%s Tx/Rx buffer valid. Transfer length valid\n",
525 			__func__);
526 
527 		/* if baud rate has been specified validate the same */
528 		if (transfer->speed_hz > PCH_MAX_BAUDRATE)
529 			transfer->speed_hz = PCH_MAX_BAUDRATE;
530 	}
531 	spin_unlock_irqrestore(&data->lock, flags);
532 
533 	/* We won't process any messages if we have been asked to terminate */
534 	if (data->status == STATUS_EXITING) {
535 		dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
536 		retval = -ESHUTDOWN;
537 		goto err_out;
538 	}
539 
540 	/* If suspended ,return -EINVAL */
541 	if (data->board_dat->suspend_sts) {
542 		dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
543 		retval = -EINVAL;
544 		goto err_out;
545 	}
546 
547 	/* set status of message */
548 	pmsg->actual_length = 0;
549 	dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
550 
551 	pmsg->status = -EINPROGRESS;
552 	spin_lock_irqsave(&data->lock, flags);
553 	/* add message to queue */
554 	list_add_tail(&pmsg->queue, &data->queue);
555 	spin_unlock_irqrestore(&data->lock, flags);
556 
557 	dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
558 
559 	/* schedule work queue to run */
560 	queue_work(data->wk, &data->work);
561 	dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
562 
563 	retval = 0;
564 
565 err_out:
566 	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
567 	return retval;
568 err_return_spinlock:
569 	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
570 	spin_unlock_irqrestore(&data->lock, flags);
571 	return retval;
572 }
573 
574 static inline void pch_spi_select_chip(struct pch_spi_data *data,
575 				       struct spi_device *pspi)
576 {
577 	if (data->current_chip != NULL) {
578 		if (pspi->chip_select != data->n_curnt_chip) {
579 			dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
580 			data->current_chip = NULL;
581 		}
582 	}
583 
584 	data->current_chip = pspi;
585 
586 	data->n_curnt_chip = data->current_chip->chip_select;
587 
588 	dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
589 	pch_spi_setup_transfer(pspi);
590 }
591 
592 static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
593 {
594 	int size;
595 	u32 n_writes;
596 	int j;
597 	struct spi_message *pmsg, *tmp;
598 	const u8 *tx_buf;
599 	const u16 *tx_sbuf;
600 
601 	/* set baud rate if needed */
602 	if (data->cur_trans->speed_hz) {
603 		dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
604 		pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
605 	}
606 
607 	/* set bits per word if needed */
608 	if (data->cur_trans->bits_per_word &&
609 	    (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
610 		dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
611 		pch_spi_set_bits_per_word(data->master,
612 					  data->cur_trans->bits_per_word);
613 		*bpw = data->cur_trans->bits_per_word;
614 	} else {
615 		*bpw = data->current_msg->spi->bits_per_word;
616 	}
617 
618 	/* reset Tx/Rx index */
619 	data->tx_index = 0;
620 	data->rx_index = 0;
621 
622 	data->bpw_len = data->cur_trans->len / (*bpw / 8);
623 
624 	/* find alloc size */
625 	size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
626 
627 	/* allocate memory for pkt_tx_buff & pkt_rx_buffer */
628 	data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
629 	if (data->pkt_tx_buff != NULL) {
630 		data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
631 		if (!data->pkt_rx_buff)
632 			kfree(data->pkt_tx_buff);
633 	}
634 
635 	if (!data->pkt_rx_buff) {
636 		/* flush queue and set status of all transfers to -ENOMEM */
637 		dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__);
638 		list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
639 			pmsg->status = -ENOMEM;
640 
641 			if (pmsg->complete)
642 				pmsg->complete(pmsg->context);
643 
644 			/* delete from queue */
645 			list_del_init(&pmsg->queue);
646 		}
647 		return;
648 	}
649 
650 	/* copy Tx Data */
651 	if (data->cur_trans->tx_buf != NULL) {
652 		if (*bpw == 8) {
653 			tx_buf = data->cur_trans->tx_buf;
654 			for (j = 0; j < data->bpw_len; j++)
655 				data->pkt_tx_buff[j] = *tx_buf++;
656 		} else {
657 			tx_sbuf = data->cur_trans->tx_buf;
658 			for (j = 0; j < data->bpw_len; j++)
659 				data->pkt_tx_buff[j] = *tx_sbuf++;
660 		}
661 	}
662 
663 	/* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
664 	n_writes = data->bpw_len;
665 	if (n_writes > PCH_MAX_FIFO_DEPTH)
666 		n_writes = PCH_MAX_FIFO_DEPTH;
667 
668 	dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
669 		"0x2 to SSNXCR\n", __func__);
670 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
671 
672 	for (j = 0; j < n_writes; j++)
673 		pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
674 
675 	/* update tx_index */
676 	data->tx_index = j;
677 
678 	/* reset transfer complete flag */
679 	data->transfer_complete = false;
680 	data->transfer_active = true;
681 }
682 
683 static void pch_spi_nomore_transfer(struct pch_spi_data *data)
684 {
685 	struct spi_message *pmsg, *tmp;
686 	dev_dbg(&data->master->dev, "%s called\n", __func__);
687 	/* Invoke complete callback
688 	 * [To the spi core..indicating end of transfer] */
689 	data->current_msg->status = 0;
690 
691 	if (data->current_msg->complete) {
692 		dev_dbg(&data->master->dev,
693 			"%s:Invoking callback of SPI core\n", __func__);
694 		data->current_msg->complete(data->current_msg->context);
695 	}
696 
697 	/* update status in global variable */
698 	data->bcurrent_msg_processing = false;
699 
700 	dev_dbg(&data->master->dev,
701 		"%s:data->bcurrent_msg_processing = false\n", __func__);
702 
703 	data->current_msg = NULL;
704 	data->cur_trans = NULL;
705 
706 	/* check if we have items in list and not suspending
707 	 * return 1 if list empty */
708 	if ((list_empty(&data->queue) == 0) &&
709 	    (!data->board_dat->suspend_sts) &&
710 	    (data->status != STATUS_EXITING)) {
711 		/* We have some more work to do (either there is more tranint
712 		 * bpw;sfer requests in the current message or there are
713 		 *more messages)
714 		 */
715 		dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
716 		queue_work(data->wk, &data->work);
717 	} else if (data->board_dat->suspend_sts ||
718 		   data->status == STATUS_EXITING) {
719 		dev_dbg(&data->master->dev,
720 			"%s suspend/remove initiated, flushing queue\n",
721 			__func__);
722 		list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
723 			pmsg->status = -EIO;
724 
725 			if (pmsg->complete)
726 				pmsg->complete(pmsg->context);
727 
728 			/* delete from queue */
729 			list_del_init(&pmsg->queue);
730 		}
731 	}
732 }
733 
734 static void pch_spi_set_ir(struct pch_spi_data *data)
735 {
736 	/* enable interrupts, set threshold, enable SPI */
737 	if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
738 		/* set receive threshold to PCH_RX_THOLD */
739 		pch_spi_setclr_reg(data->master, PCH_SPCR,
740 				   PCH_RX_THOLD << SPCR_RFIC_FIELD |
741 				   SPCR_FIE_BIT | SPCR_RFIE_BIT |
742 				   SPCR_ORIE_BIT | SPCR_SPE_BIT,
743 				   MASK_RFIC_SPCR_BITS | PCH_ALL);
744 	else
745 		/* set receive threshold to maximum */
746 		pch_spi_setclr_reg(data->master, PCH_SPCR,
747 				   PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
748 				   SPCR_FIE_BIT | SPCR_ORIE_BIT |
749 				   SPCR_SPE_BIT,
750 				   MASK_RFIC_SPCR_BITS | PCH_ALL);
751 
752 	/* Wait until the transfer completes; go to sleep after
753 				 initiating the transfer. */
754 	dev_dbg(&data->master->dev,
755 		"%s:waiting for transfer to get over\n", __func__);
756 
757 	wait_event_interruptible(data->wait, data->transfer_complete);
758 
759 	/* clear all interrupts */
760 	pch_spi_writereg(data->master, PCH_SPSR,
761 			 pch_spi_readreg(data->master, PCH_SPSR));
762 	/* Disable interrupts and SPI transfer */
763 	pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
764 	/* clear FIFO */
765 	pch_spi_clear_fifo(data->master);
766 }
767 
768 static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
769 {
770 	int j;
771 	u8 *rx_buf;
772 	u16 *rx_sbuf;
773 
774 	/* copy Rx Data */
775 	if (!data->cur_trans->rx_buf)
776 		return;
777 
778 	if (bpw == 8) {
779 		rx_buf = data->cur_trans->rx_buf;
780 		for (j = 0; j < data->bpw_len; j++)
781 			*rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
782 	} else {
783 		rx_sbuf = data->cur_trans->rx_buf;
784 		for (j = 0; j < data->bpw_len; j++)
785 			*rx_sbuf++ = data->pkt_rx_buff[j];
786 	}
787 }
788 
789 static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
790 {
791 	int j;
792 	u8 *rx_buf;
793 	u16 *rx_sbuf;
794 	const u8 *rx_dma_buf;
795 	const u16 *rx_dma_sbuf;
796 
797 	/* copy Rx Data */
798 	if (!data->cur_trans->rx_buf)
799 		return;
800 
801 	if (bpw == 8) {
802 		rx_buf = data->cur_trans->rx_buf;
803 		rx_dma_buf = data->dma.rx_buf_virt;
804 		for (j = 0; j < data->bpw_len; j++)
805 			*rx_buf++ = *rx_dma_buf++ & 0xFF;
806 		data->cur_trans->rx_buf = rx_buf;
807 	} else {
808 		rx_sbuf = data->cur_trans->rx_buf;
809 		rx_dma_sbuf = data->dma.rx_buf_virt;
810 		for (j = 0; j < data->bpw_len; j++)
811 			*rx_sbuf++ = *rx_dma_sbuf++;
812 		data->cur_trans->rx_buf = rx_sbuf;
813 	}
814 }
815 
816 static int pch_spi_start_transfer(struct pch_spi_data *data)
817 {
818 	struct pch_spi_dma_ctrl *dma;
819 	unsigned long flags;
820 	int rtn;
821 
822 	dma = &data->dma;
823 
824 	spin_lock_irqsave(&data->lock, flags);
825 
826 	/* disable interrupts, SPI set enable */
827 	pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
828 
829 	spin_unlock_irqrestore(&data->lock, flags);
830 
831 	/* Wait until the transfer completes; go to sleep after
832 				 initiating the transfer. */
833 	dev_dbg(&data->master->dev,
834 		"%s:waiting for transfer to get over\n", __func__);
835 	rtn = wait_event_interruptible_timeout(data->wait,
836 					       data->transfer_complete,
837 					       msecs_to_jiffies(2 * HZ));
838 	if (!rtn)
839 		dev_err(&data->master->dev,
840 			"%s wait-event timeout\n", __func__);
841 
842 	dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
843 			    DMA_FROM_DEVICE);
844 
845 	dma_sync_sg_for_cpu(&data->master->dev, dma->sg_tx_p, dma->nent,
846 			    DMA_FROM_DEVICE);
847 	memset(data->dma.tx_buf_virt, 0, PAGE_SIZE);
848 
849 	async_tx_ack(dma->desc_rx);
850 	async_tx_ack(dma->desc_tx);
851 	kfree(dma->sg_tx_p);
852 	kfree(dma->sg_rx_p);
853 
854 	spin_lock_irqsave(&data->lock, flags);
855 
856 	/* clear fifo threshold, disable interrupts, disable SPI transfer */
857 	pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
858 			   MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
859 			   SPCR_SPE_BIT);
860 	/* clear all interrupts */
861 	pch_spi_writereg(data->master, PCH_SPSR,
862 			 pch_spi_readreg(data->master, PCH_SPSR));
863 	/* clear FIFO */
864 	pch_spi_clear_fifo(data->master);
865 
866 	spin_unlock_irqrestore(&data->lock, flags);
867 
868 	return rtn;
869 }
870 
871 static void pch_dma_rx_complete(void *arg)
872 {
873 	struct pch_spi_data *data = arg;
874 
875 	/* transfer is completed;inform pch_spi_process_messages_dma */
876 	data->transfer_complete = true;
877 	wake_up_interruptible(&data->wait);
878 }
879 
880 static bool pch_spi_filter(struct dma_chan *chan, void *slave)
881 {
882 	struct pch_dma_slave *param = slave;
883 
884 	if ((chan->chan_id == param->chan_id) &&
885 	    (param->dma_dev == chan->device->dev)) {
886 		chan->private = param;
887 		return true;
888 	} else {
889 		return false;
890 	}
891 }
892 
893 static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
894 {
895 	dma_cap_mask_t mask;
896 	struct dma_chan *chan;
897 	struct pci_dev *dma_dev;
898 	struct pch_dma_slave *param;
899 	struct pch_spi_dma_ctrl *dma;
900 	unsigned int width;
901 
902 	if (bpw == 8)
903 		width = PCH_DMA_WIDTH_1_BYTE;
904 	else
905 		width = PCH_DMA_WIDTH_2_BYTES;
906 
907 	dma = &data->dma;
908 	dma_cap_zero(mask);
909 	dma_cap_set(DMA_SLAVE, mask);
910 
911 	/* Get DMA's dev information */
912 	dma_dev = pci_get_bus_and_slot(data->board_dat->pdev->bus->number,
913 				       PCI_DEVFN(12, 0));
914 
915 	/* Set Tx DMA */
916 	param = &dma->param_tx;
917 	param->dma_dev = &dma_dev->dev;
918 	param->chan_id = data->master->bus_num * 2; /* Tx = 0, 2 */
919 	param->tx_reg = data->io_base_addr + PCH_SPDWR;
920 	param->width = width;
921 	chan = dma_request_channel(mask, pch_spi_filter, param);
922 	if (!chan) {
923 		dev_err(&data->master->dev,
924 			"ERROR: dma_request_channel FAILS(Tx)\n");
925 		data->use_dma = 0;
926 		return;
927 	}
928 	dma->chan_tx = chan;
929 
930 	/* Set Rx DMA */
931 	param = &dma->param_rx;
932 	param->dma_dev = &dma_dev->dev;
933 	param->chan_id = data->master->bus_num * 2 + 1; /* Rx = Tx + 1 */
934 	param->rx_reg = data->io_base_addr + PCH_SPDRR;
935 	param->width = width;
936 	chan = dma_request_channel(mask, pch_spi_filter, param);
937 	if (!chan) {
938 		dev_err(&data->master->dev,
939 			"ERROR: dma_request_channel FAILS(Rx)\n");
940 		dma_release_channel(dma->chan_tx);
941 		dma->chan_tx = NULL;
942 		data->use_dma = 0;
943 		return;
944 	}
945 	dma->chan_rx = chan;
946 }
947 
948 static void pch_spi_release_dma(struct pch_spi_data *data)
949 {
950 	struct pch_spi_dma_ctrl *dma;
951 
952 	dma = &data->dma;
953 	if (dma->chan_tx) {
954 		dma_release_channel(dma->chan_tx);
955 		dma->chan_tx = NULL;
956 	}
957 	if (dma->chan_rx) {
958 		dma_release_channel(dma->chan_rx);
959 		dma->chan_rx = NULL;
960 	}
961 	return;
962 }
963 
964 static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
965 {
966 	const u8 *tx_buf;
967 	const u16 *tx_sbuf;
968 	u8 *tx_dma_buf;
969 	u16 *tx_dma_sbuf;
970 	struct scatterlist *sg;
971 	struct dma_async_tx_descriptor *desc_tx;
972 	struct dma_async_tx_descriptor *desc_rx;
973 	int num;
974 	int i;
975 	int size;
976 	int rem;
977 	int head;
978 	unsigned long flags;
979 	struct pch_spi_dma_ctrl *dma;
980 
981 	dma = &data->dma;
982 
983 	/* set baud rate if needed */
984 	if (data->cur_trans->speed_hz) {
985 		dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
986 		spin_lock_irqsave(&data->lock, flags);
987 		pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
988 		spin_unlock_irqrestore(&data->lock, flags);
989 	}
990 
991 	/* set bits per word if needed */
992 	if (data->cur_trans->bits_per_word &&
993 	    (data->current_msg->spi->bits_per_word !=
994 	     data->cur_trans->bits_per_word)) {
995 		dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
996 		spin_lock_irqsave(&data->lock, flags);
997 		pch_spi_set_bits_per_word(data->master,
998 					  data->cur_trans->bits_per_word);
999 		spin_unlock_irqrestore(&data->lock, flags);
1000 		*bpw = data->cur_trans->bits_per_word;
1001 	} else {
1002 		*bpw = data->current_msg->spi->bits_per_word;
1003 	}
1004 	data->bpw_len = data->cur_trans->len / (*bpw / 8);
1005 
1006 	if (data->bpw_len > PCH_BUF_SIZE) {
1007 		data->bpw_len = PCH_BUF_SIZE;
1008 		data->cur_trans->len -= PCH_BUF_SIZE;
1009 	}
1010 
1011 	/* copy Tx Data */
1012 	if (data->cur_trans->tx_buf != NULL) {
1013 		if (*bpw == 8) {
1014 			tx_buf = data->cur_trans->tx_buf;
1015 			tx_dma_buf = dma->tx_buf_virt;
1016 			for (i = 0; i < data->bpw_len; i++)
1017 				*tx_dma_buf++ = *tx_buf++;
1018 		} else {
1019 			tx_sbuf = data->cur_trans->tx_buf;
1020 			tx_dma_sbuf = dma->tx_buf_virt;
1021 			for (i = 0; i < data->bpw_len; i++)
1022 				*tx_dma_sbuf++ = *tx_sbuf++;
1023 		}
1024 	}
1025 
1026 	/* Calculate Rx parameter for DMA transmitting */
1027 	if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
1028 		if (data->bpw_len % PCH_DMA_TRANS_SIZE) {
1029 			num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
1030 			rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
1031 		} else {
1032 			num = data->bpw_len / PCH_DMA_TRANS_SIZE;
1033 			rem = PCH_DMA_TRANS_SIZE;
1034 		}
1035 		size = PCH_DMA_TRANS_SIZE;
1036 	} else {
1037 		num = 1;
1038 		size = data->bpw_len;
1039 		rem = data->bpw_len;
1040 	}
1041 	dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
1042 		__func__, num, size, rem);
1043 	spin_lock_irqsave(&data->lock, flags);
1044 
1045 	/* set receive fifo threshold and transmit fifo threshold */
1046 	pch_spi_setclr_reg(data->master, PCH_SPCR,
1047 			   ((size - 1) << SPCR_RFIC_FIELD) |
1048 			   (PCH_TX_THOLD << SPCR_TFIC_FIELD),
1049 			   MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
1050 
1051 	spin_unlock_irqrestore(&data->lock, flags);
1052 
1053 	/* RX */
1054 	dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
1055 	sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
1056 	/* offset, length setting */
1057 	sg = dma->sg_rx_p;
1058 	for (i = 0; i < num; i++, sg++) {
1059 		if (i == (num - 2)) {
1060 			sg->offset = size * i;
1061 			sg->offset = sg->offset * (*bpw / 8);
1062 			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
1063 				    sg->offset);
1064 			sg_dma_len(sg) = rem;
1065 		} else if (i == (num - 1)) {
1066 			sg->offset = size * (i - 1) + rem;
1067 			sg->offset = sg->offset * (*bpw / 8);
1068 			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1069 				    sg->offset);
1070 			sg_dma_len(sg) = size;
1071 		} else {
1072 			sg->offset = size * i;
1073 			sg->offset = sg->offset * (*bpw / 8);
1074 			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1075 				    sg->offset);
1076 			sg_dma_len(sg) = size;
1077 		}
1078 		sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
1079 	}
1080 	sg = dma->sg_rx_p;
1081 	desc_rx = dmaengine_prep_slave_sg(dma->chan_rx, sg,
1082 					num, DMA_DEV_TO_MEM,
1083 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1084 	if (!desc_rx) {
1085 		dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
1086 			__func__);
1087 		return;
1088 	}
1089 	dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
1090 	desc_rx->callback = pch_dma_rx_complete;
1091 	desc_rx->callback_param = data;
1092 	dma->nent = num;
1093 	dma->desc_rx = desc_rx;
1094 
1095 	/* Calculate Tx parameter for DMA transmitting */
1096 	if (data->bpw_len > PCH_MAX_FIFO_DEPTH) {
1097 		head = PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE;
1098 		if (data->bpw_len % PCH_DMA_TRANS_SIZE > 4) {
1099 			num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
1100 			rem = data->bpw_len % PCH_DMA_TRANS_SIZE - head;
1101 		} else {
1102 			num = data->bpw_len / PCH_DMA_TRANS_SIZE;
1103 			rem = data->bpw_len % PCH_DMA_TRANS_SIZE +
1104 			      PCH_DMA_TRANS_SIZE - head;
1105 		}
1106 		size = PCH_DMA_TRANS_SIZE;
1107 	} else {
1108 		num = 1;
1109 		size = data->bpw_len;
1110 		rem = data->bpw_len;
1111 		head = 0;
1112 	}
1113 
1114 	dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
1115 	sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
1116 	/* offset, length setting */
1117 	sg = dma->sg_tx_p;
1118 	for (i = 0; i < num; i++, sg++) {
1119 		if (i == 0) {
1120 			sg->offset = 0;
1121 			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size + head,
1122 				    sg->offset);
1123 			sg_dma_len(sg) = size + head;
1124 		} else if (i == (num - 1)) {
1125 			sg->offset = head + size * i;
1126 			sg->offset = sg->offset * (*bpw / 8);
1127 			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
1128 				    sg->offset);
1129 			sg_dma_len(sg) = rem;
1130 		} else {
1131 			sg->offset = head + size * i;
1132 			sg->offset = sg->offset * (*bpw / 8);
1133 			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
1134 				    sg->offset);
1135 			sg_dma_len(sg) = size;
1136 		}
1137 		sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
1138 	}
1139 	sg = dma->sg_tx_p;
1140 	desc_tx = dmaengine_prep_slave_sg(dma->chan_tx,
1141 					sg, num, DMA_MEM_TO_DEV,
1142 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1143 	if (!desc_tx) {
1144 		dev_err(&data->master->dev, "%s:device_prep_slave_sg Failed\n",
1145 			__func__);
1146 		return;
1147 	}
1148 	dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
1149 	desc_tx->callback = NULL;
1150 	desc_tx->callback_param = data;
1151 	dma->nent = num;
1152 	dma->desc_tx = desc_tx;
1153 
1154 	dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
1155 		"0x2 to SSNXCR\n", __func__);
1156 
1157 	spin_lock_irqsave(&data->lock, flags);
1158 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
1159 	desc_rx->tx_submit(desc_rx);
1160 	desc_tx->tx_submit(desc_tx);
1161 	spin_unlock_irqrestore(&data->lock, flags);
1162 
1163 	/* reset transfer complete flag */
1164 	data->transfer_complete = false;
1165 }
1166 
1167 static void pch_spi_process_messages(struct work_struct *pwork)
1168 {
1169 	struct spi_message *pmsg, *tmp;
1170 	struct pch_spi_data *data;
1171 	int bpw;
1172 
1173 	data = container_of(pwork, struct pch_spi_data, work);
1174 	dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
1175 
1176 	spin_lock(&data->lock);
1177 	/* check if suspend has been initiated;if yes flush queue */
1178 	if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
1179 		dev_dbg(&data->master->dev,
1180 			"%s suspend/remove initiated, flushing queue\n", __func__);
1181 		list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
1182 			pmsg->status = -EIO;
1183 
1184 			if (pmsg->complete) {
1185 				spin_unlock(&data->lock);
1186 				pmsg->complete(pmsg->context);
1187 				spin_lock(&data->lock);
1188 			}
1189 
1190 			/* delete from queue */
1191 			list_del_init(&pmsg->queue);
1192 		}
1193 
1194 		spin_unlock(&data->lock);
1195 		return;
1196 	}
1197 
1198 	data->bcurrent_msg_processing = true;
1199 	dev_dbg(&data->master->dev,
1200 		"%s Set data->bcurrent_msg_processing= true\n", __func__);
1201 
1202 	/* Get the message from the queue and delete it from there. */
1203 	data->current_msg = list_entry(data->queue.next, struct spi_message,
1204 					queue);
1205 
1206 	list_del_init(&data->current_msg->queue);
1207 
1208 	data->current_msg->status = 0;
1209 
1210 	pch_spi_select_chip(data, data->current_msg->spi);
1211 
1212 	spin_unlock(&data->lock);
1213 
1214 	if (data->use_dma)
1215 		pch_spi_request_dma(data,
1216 				    data->current_msg->spi->bits_per_word);
1217 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
1218 	do {
1219 		int cnt;
1220 		/* If we are already processing a message get the next
1221 		transfer structure from the message otherwise retrieve
1222 		the 1st transfer request from the message. */
1223 		spin_lock(&data->lock);
1224 		if (data->cur_trans == NULL) {
1225 			data->cur_trans =
1226 				list_entry(data->current_msg->transfers.next,
1227 					   struct spi_transfer, transfer_list);
1228 			dev_dbg(&data->master->dev, "%s "
1229 				":Getting 1st transfer message\n", __func__);
1230 		} else {
1231 			data->cur_trans =
1232 				list_entry(data->cur_trans->transfer_list.next,
1233 					   struct spi_transfer, transfer_list);
1234 			dev_dbg(&data->master->dev, "%s "
1235 				":Getting next transfer message\n", __func__);
1236 		}
1237 		spin_unlock(&data->lock);
1238 
1239 		if (!data->cur_trans->len)
1240 			goto out;
1241 		cnt = (data->cur_trans->len - 1) / PCH_BUF_SIZE + 1;
1242 		data->save_total_len = data->cur_trans->len;
1243 		if (data->use_dma) {
1244 			int i;
1245 			char *save_rx_buf = data->cur_trans->rx_buf;
1246 			for (i = 0; i < cnt; i ++) {
1247 				pch_spi_handle_dma(data, &bpw);
1248 				if (!pch_spi_start_transfer(data)) {
1249 					data->transfer_complete = true;
1250 					data->current_msg->status = -EIO;
1251 					data->current_msg->complete
1252 						   (data->current_msg->context);
1253 					data->bcurrent_msg_processing = false;
1254 					data->current_msg = NULL;
1255 					data->cur_trans = NULL;
1256 					goto out;
1257 				}
1258 				pch_spi_copy_rx_data_for_dma(data, bpw);
1259 			}
1260 			data->cur_trans->rx_buf = save_rx_buf;
1261 		} else {
1262 			pch_spi_set_tx(data, &bpw);
1263 			pch_spi_set_ir(data);
1264 			pch_spi_copy_rx_data(data, bpw);
1265 			kfree(data->pkt_rx_buff);
1266 			data->pkt_rx_buff = NULL;
1267 			kfree(data->pkt_tx_buff);
1268 			data->pkt_tx_buff = NULL;
1269 		}
1270 		/* increment message count */
1271 		data->cur_trans->len = data->save_total_len;
1272 		data->current_msg->actual_length += data->cur_trans->len;
1273 
1274 		dev_dbg(&data->master->dev,
1275 			"%s:data->current_msg->actual_length=%d\n",
1276 			__func__, data->current_msg->actual_length);
1277 
1278 		/* check for delay */
1279 		if (data->cur_trans->delay_usecs) {
1280 			dev_dbg(&data->master->dev, "%s:"
1281 				"delay in usec=%d\n", __func__,
1282 				data->cur_trans->delay_usecs);
1283 			udelay(data->cur_trans->delay_usecs);
1284 		}
1285 
1286 		spin_lock(&data->lock);
1287 
1288 		/* No more transfer in this message. */
1289 		if ((data->cur_trans->transfer_list.next) ==
1290 		    &(data->current_msg->transfers)) {
1291 			pch_spi_nomore_transfer(data);
1292 		}
1293 
1294 		spin_unlock(&data->lock);
1295 
1296 	} while (data->cur_trans != NULL);
1297 
1298 out:
1299 	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH);
1300 	if (data->use_dma)
1301 		pch_spi_release_dma(data);
1302 }
1303 
1304 static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
1305 				   struct pch_spi_data *data)
1306 {
1307 	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1308 
1309 	/* free workqueue */
1310 	if (data->wk != NULL) {
1311 		destroy_workqueue(data->wk);
1312 		data->wk = NULL;
1313 		dev_dbg(&board_dat->pdev->dev,
1314 			"%s destroy_workqueue invoked successfully\n",
1315 			__func__);
1316 	}
1317 }
1318 
1319 static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,
1320 				 struct pch_spi_data *data)
1321 {
1322 	int retval = 0;
1323 
1324 	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1325 
1326 	/* create workqueue */
1327 	data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
1328 	if (!data->wk) {
1329 		dev_err(&board_dat->pdev->dev,
1330 			"%s create_singlet hread_workqueue failed\n", __func__);
1331 		retval = -EBUSY;
1332 		goto err_return;
1333 	}
1334 
1335 	/* reset PCH SPI h/w */
1336 	pch_spi_reset(data->master);
1337 	dev_dbg(&board_dat->pdev->dev,
1338 		"%s pch_spi_reset invoked successfully\n", __func__);
1339 
1340 	dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
1341 
1342 err_return:
1343 	if (retval != 0) {
1344 		dev_err(&board_dat->pdev->dev,
1345 			"%s FAIL:invoking pch_spi_free_resources\n", __func__);
1346 		pch_spi_free_resources(board_dat, data);
1347 	}
1348 
1349 	dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
1350 
1351 	return retval;
1352 }
1353 
1354 static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
1355 			     struct pch_spi_data *data)
1356 {
1357 	struct pch_spi_dma_ctrl *dma;
1358 
1359 	dma = &data->dma;
1360 	if (dma->tx_buf_dma)
1361 		dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1362 				  dma->tx_buf_virt, dma->tx_buf_dma);
1363 	if (dma->rx_buf_dma)
1364 		dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1365 				  dma->rx_buf_virt, dma->rx_buf_dma);
1366 	return;
1367 }
1368 
1369 static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
1370 			      struct pch_spi_data *data)
1371 {
1372 	struct pch_spi_dma_ctrl *dma;
1373 
1374 	dma = &data->dma;
1375 	/* Get Consistent memory for Tx DMA */
1376 	dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1377 				PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
1378 	/* Get Consistent memory for Rx DMA */
1379 	dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1380 				PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
1381 }
1382 
1383 static int pch_spi_pd_probe(struct platform_device *plat_dev)
1384 {
1385 	int ret;
1386 	struct spi_master *master;
1387 	struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1388 	struct pch_spi_data *data;
1389 
1390 	dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
1391 
1392 	master = spi_alloc_master(&board_dat->pdev->dev,
1393 				  sizeof(struct pch_spi_data));
1394 	if (!master) {
1395 		dev_err(&plat_dev->dev, "spi_alloc_master[%d] failed.\n",
1396 			plat_dev->id);
1397 		return -ENOMEM;
1398 	}
1399 
1400 	data = spi_master_get_devdata(master);
1401 	data->master = master;
1402 
1403 	platform_set_drvdata(plat_dev, data);
1404 
1405 	/* baseaddress + address offset) */
1406 	data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
1407 					 PCH_ADDRESS_SIZE * plat_dev->id;
1408 	data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
1409 	if (!data->io_remap_addr) {
1410 		dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
1411 		ret = -ENOMEM;
1412 		goto err_pci_iomap;
1413 	}
1414 	data->io_remap_addr += PCH_ADDRESS_SIZE * plat_dev->id;
1415 
1416 	dev_dbg(&plat_dev->dev, "[ch%d] remap_addr=%p\n",
1417 		plat_dev->id, data->io_remap_addr);
1418 
1419 	/* initialize members of SPI master */
1420 	master->num_chipselect = PCH_MAX_CS;
1421 	master->setup = pch_spi_setup;
1422 	master->transfer = pch_spi_transfer;
1423 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1424 	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
1425 
1426 	data->board_dat = board_dat;
1427 	data->plat_dev = plat_dev;
1428 	data->n_curnt_chip = 255;
1429 	data->status = STATUS_RUNNING;
1430 	data->ch = plat_dev->id;
1431 	data->use_dma = use_dma;
1432 
1433 	INIT_LIST_HEAD(&data->queue);
1434 	spin_lock_init(&data->lock);
1435 	INIT_WORK(&data->work, pch_spi_process_messages);
1436 	init_waitqueue_head(&data->wait);
1437 
1438 	ret = pch_spi_get_resources(board_dat, data);
1439 	if (ret) {
1440 		dev_err(&plat_dev->dev, "%s fail(retval=%d)\n", __func__, ret);
1441 		goto err_spi_get_resources;
1442 	}
1443 
1444 	ret = request_irq(board_dat->pdev->irq, pch_spi_handler,
1445 			  IRQF_SHARED, KBUILD_MODNAME, data);
1446 	if (ret) {
1447 		dev_err(&plat_dev->dev,
1448 			"%s request_irq failed\n", __func__);
1449 		goto err_request_irq;
1450 	}
1451 	data->irq_reg_sts = true;
1452 
1453 	pch_spi_set_master_mode(master);
1454 
1455 	ret = spi_register_master(master);
1456 	if (ret != 0) {
1457 		dev_err(&plat_dev->dev,
1458 			"%s spi_register_master FAILED\n", __func__);
1459 		goto err_spi_register_master;
1460 	}
1461 
1462 	if (use_dma) {
1463 		dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
1464 		pch_alloc_dma_buf(board_dat, data);
1465 	}
1466 
1467 	return 0;
1468 
1469 err_spi_register_master:
1470 	free_irq(board_dat->pdev->irq, data);
1471 err_request_irq:
1472 	pch_spi_free_resources(board_dat, data);
1473 err_spi_get_resources:
1474 	pci_iounmap(board_dat->pdev, data->io_remap_addr);
1475 err_pci_iomap:
1476 	spi_master_put(master);
1477 
1478 	return ret;
1479 }
1480 
1481 static int pch_spi_pd_remove(struct platform_device *plat_dev)
1482 {
1483 	struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1484 	struct pch_spi_data *data = platform_get_drvdata(plat_dev);
1485 	int count;
1486 	unsigned long flags;
1487 
1488 	dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
1489 		__func__, plat_dev->id, board_dat->pdev->irq);
1490 
1491 	if (use_dma)
1492 		pch_free_dma_buf(board_dat, data);
1493 
1494 	/* check for any pending messages; no action is taken if the queue
1495 	 * is still full; but at least we tried.  Unload anyway */
1496 	count = 500;
1497 	spin_lock_irqsave(&data->lock, flags);
1498 	data->status = STATUS_EXITING;
1499 	while ((list_empty(&data->queue) == 0) && --count) {
1500 		dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
1501 			__func__);
1502 		spin_unlock_irqrestore(&data->lock, flags);
1503 		msleep(PCH_SLEEP_TIME);
1504 		spin_lock_irqsave(&data->lock, flags);
1505 	}
1506 	spin_unlock_irqrestore(&data->lock, flags);
1507 
1508 	pch_spi_free_resources(board_dat, data);
1509 	/* disable interrupts & free IRQ */
1510 	if (data->irq_reg_sts) {
1511 		/* disable interrupts */
1512 		pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1513 		data->irq_reg_sts = false;
1514 		free_irq(board_dat->pdev->irq, data);
1515 	}
1516 
1517 	pci_iounmap(board_dat->pdev, data->io_remap_addr);
1518 	spi_unregister_master(data->master);
1519 
1520 	return 0;
1521 }
1522 #ifdef CONFIG_PM
1523 static int pch_spi_pd_suspend(struct platform_device *pd_dev,
1524 			      pm_message_t state)
1525 {
1526 	u8 count;
1527 	struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1528 	struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1529 
1530 	dev_dbg(&pd_dev->dev, "%s ENTRY\n", __func__);
1531 
1532 	if (!board_dat) {
1533 		dev_err(&pd_dev->dev,
1534 			"%s pci_get_drvdata returned NULL\n", __func__);
1535 		return -EFAULT;
1536 	}
1537 
1538 	/* check if the current message is processed:
1539 	   Only after thats done the transfer will be suspended */
1540 	count = 255;
1541 	while ((--count) > 0) {
1542 		if (!(data->bcurrent_msg_processing))
1543 			break;
1544 		msleep(PCH_SLEEP_TIME);
1545 	}
1546 
1547 	/* Free IRQ */
1548 	if (data->irq_reg_sts) {
1549 		/* disable all interrupts */
1550 		pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1551 		pch_spi_reset(data->master);
1552 		free_irq(board_dat->pdev->irq, data);
1553 
1554 		data->irq_reg_sts = false;
1555 		dev_dbg(&pd_dev->dev,
1556 			"%s free_irq invoked successfully.\n", __func__);
1557 	}
1558 
1559 	return 0;
1560 }
1561 
1562 static int pch_spi_pd_resume(struct platform_device *pd_dev)
1563 {
1564 	struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1565 	struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1566 	int retval;
1567 
1568 	if (!board_dat) {
1569 		dev_err(&pd_dev->dev,
1570 			"%s pci_get_drvdata returned NULL\n", __func__);
1571 		return -EFAULT;
1572 	}
1573 
1574 	if (!data->irq_reg_sts) {
1575 		/* register IRQ */
1576 		retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
1577 				     IRQF_SHARED, KBUILD_MODNAME, data);
1578 		if (retval < 0) {
1579 			dev_err(&pd_dev->dev,
1580 				"%s request_irq failed\n", __func__);
1581 			return retval;
1582 		}
1583 
1584 		/* reset PCH SPI h/w */
1585 		pch_spi_reset(data->master);
1586 		pch_spi_set_master_mode(data->master);
1587 		data->irq_reg_sts = true;
1588 	}
1589 	return 0;
1590 }
1591 #else
1592 #define pch_spi_pd_suspend NULL
1593 #define pch_spi_pd_resume NULL
1594 #endif
1595 
1596 static struct platform_driver pch_spi_pd_driver = {
1597 	.driver = {
1598 		.name = "pch-spi",
1599 		.owner = THIS_MODULE,
1600 	},
1601 	.probe = pch_spi_pd_probe,
1602 	.remove = pch_spi_pd_remove,
1603 	.suspend = pch_spi_pd_suspend,
1604 	.resume = pch_spi_pd_resume
1605 };
1606 
1607 static int pch_spi_probe(struct pci_dev *pdev,
1608 				   const struct pci_device_id *id)
1609 {
1610 	struct pch_spi_board_data *board_dat;
1611 	struct platform_device *pd_dev = NULL;
1612 	int retval;
1613 	int i;
1614 	struct pch_pd_dev_save *pd_dev_save;
1615 
1616 	pd_dev_save = kzalloc(sizeof(struct pch_pd_dev_save), GFP_KERNEL);
1617 	if (!pd_dev_save) {
1618 		dev_err(&pdev->dev, "%s Can't allocate pd_dev_sav\n", __func__);
1619 		return -ENOMEM;
1620 	}
1621 
1622 	board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
1623 	if (!board_dat) {
1624 		dev_err(&pdev->dev, "%s Can't allocate board_dat\n", __func__);
1625 		retval = -ENOMEM;
1626 		goto err_no_mem;
1627 	}
1628 
1629 	retval = pci_request_regions(pdev, KBUILD_MODNAME);
1630 	if (retval) {
1631 		dev_err(&pdev->dev, "%s request_region failed\n", __func__);
1632 		goto pci_request_regions;
1633 	}
1634 
1635 	board_dat->pdev = pdev;
1636 	board_dat->num = id->driver_data;
1637 	pd_dev_save->num = id->driver_data;
1638 	pd_dev_save->board_dat = board_dat;
1639 
1640 	retval = pci_enable_device(pdev);
1641 	if (retval) {
1642 		dev_err(&pdev->dev, "%s pci_enable_device failed\n", __func__);
1643 		goto pci_enable_device;
1644 	}
1645 
1646 	for (i = 0; i < board_dat->num; i++) {
1647 		pd_dev = platform_device_alloc("pch-spi", i);
1648 		if (!pd_dev) {
1649 			dev_err(&pdev->dev, "platform_device_alloc failed\n");
1650 			retval = -ENOMEM;
1651 			goto err_platform_device;
1652 		}
1653 		pd_dev_save->pd_save[i] = pd_dev;
1654 		pd_dev->dev.parent = &pdev->dev;
1655 
1656 		retval = platform_device_add_data(pd_dev, board_dat,
1657 						  sizeof(*board_dat));
1658 		if (retval) {
1659 			dev_err(&pdev->dev,
1660 				"platform_device_add_data failed\n");
1661 			platform_device_put(pd_dev);
1662 			goto err_platform_device;
1663 		}
1664 
1665 		retval = platform_device_add(pd_dev);
1666 		if (retval) {
1667 			dev_err(&pdev->dev, "platform_device_add failed\n");
1668 			platform_device_put(pd_dev);
1669 			goto err_platform_device;
1670 		}
1671 	}
1672 
1673 	pci_set_drvdata(pdev, pd_dev_save);
1674 
1675 	return 0;
1676 
1677 err_platform_device:
1678 	pci_disable_device(pdev);
1679 pci_enable_device:
1680 	pci_release_regions(pdev);
1681 pci_request_regions:
1682 	kfree(board_dat);
1683 err_no_mem:
1684 	kfree(pd_dev_save);
1685 
1686 	return retval;
1687 }
1688 
1689 static void pch_spi_remove(struct pci_dev *pdev)
1690 {
1691 	int i;
1692 	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1693 
1694 	dev_dbg(&pdev->dev, "%s ENTRY:pdev=%p\n", __func__, pdev);
1695 
1696 	for (i = 0; i < pd_dev_save->num; i++)
1697 		platform_device_unregister(pd_dev_save->pd_save[i]);
1698 
1699 	pci_disable_device(pdev);
1700 	pci_release_regions(pdev);
1701 	kfree(pd_dev_save->board_dat);
1702 	kfree(pd_dev_save);
1703 }
1704 
1705 #ifdef CONFIG_PM
1706 static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
1707 {
1708 	int retval;
1709 	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1710 
1711 	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1712 
1713 	pd_dev_save->board_dat->suspend_sts = true;
1714 
1715 	/* save config space */
1716 	retval = pci_save_state(pdev);
1717 	if (retval == 0) {
1718 		pci_enable_wake(pdev, PCI_D3hot, 0);
1719 		pci_disable_device(pdev);
1720 		pci_set_power_state(pdev, PCI_D3hot);
1721 	} else {
1722 		dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
1723 	}
1724 
1725 	return retval;
1726 }
1727 
1728 static int pch_spi_resume(struct pci_dev *pdev)
1729 {
1730 	int retval;
1731 	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1732 	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1733 
1734 	pci_set_power_state(pdev, PCI_D0);
1735 	pci_restore_state(pdev);
1736 
1737 	retval = pci_enable_device(pdev);
1738 	if (retval < 0) {
1739 		dev_err(&pdev->dev,
1740 			"%s pci_enable_device failed\n", __func__);
1741 	} else {
1742 		pci_enable_wake(pdev, PCI_D3hot, 0);
1743 
1744 		/* set suspend status to false */
1745 		pd_dev_save->board_dat->suspend_sts = false;
1746 	}
1747 
1748 	return retval;
1749 }
1750 #else
1751 #define pch_spi_suspend NULL
1752 #define pch_spi_resume NULL
1753 
1754 #endif
1755 
1756 static struct pci_driver pch_spi_pcidev_driver = {
1757 	.name = "pch_spi",
1758 	.id_table = pch_spi_pcidev_id,
1759 	.probe = pch_spi_probe,
1760 	.remove = pch_spi_remove,
1761 	.suspend = pch_spi_suspend,
1762 	.resume = pch_spi_resume,
1763 };
1764 
1765 static int __init pch_spi_init(void)
1766 {
1767 	int ret;
1768 	ret = platform_driver_register(&pch_spi_pd_driver);
1769 	if (ret)
1770 		return ret;
1771 
1772 	ret = pci_register_driver(&pch_spi_pcidev_driver);
1773 	if (ret) {
1774 		platform_driver_unregister(&pch_spi_pd_driver);
1775 		return ret;
1776 	}
1777 
1778 	return 0;
1779 }
1780 module_init(pch_spi_init);
1781 
1782 static void __exit pch_spi_exit(void)
1783 {
1784 	pci_unregister_driver(&pch_spi_pcidev_driver);
1785 	platform_driver_unregister(&pch_spi_pd_driver);
1786 }
1787 module_exit(pch_spi_exit);
1788 
1789 module_param(use_dma, int, 0644);
1790 MODULE_PARM_DESC(use_dma,
1791 		 "to use DMA for data transfers pass 1 else 0; default 1");
1792 
1793 MODULE_LICENSE("GPL");
1794 MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semiconductor ML7xxx IOH SPI Driver");
1795 MODULE_DEVICE_TABLE(pci, pch_spi_pcidev_id);
1796 
1797