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
16#include <linux/delay.h>
17#include <linux/pci.h>
18#include <linux/wait.h>
19#include <linux/spi/spi.h>
20#include <linux/interrupt.h>
21#include <linux/sched.h>
22#include <linux/spi/spidev.h>
23#include <linux/module.h>
24#include <linux/device.h>
25#include <linux/platform_device.h>
26
27#include <linux/dmaengine.h>
28#include <linux/pch_dma.h>
29
30/* Register offsets */
31#define PCH_SPCR		0x00	/* SPI control register */
32#define PCH_SPBRR		0x04	/* SPI baud rate register */
33#define PCH_SPSR		0x08	/* SPI status register */
34#define PCH_SPDWR		0x0C	/* SPI write data register */
35#define PCH_SPDRR		0x10	/* SPI read data register */
36#define PCH_SSNXCR		0x18	/* SSN Expand Control Register */
37#define PCH_SRST		0x1C	/* SPI reset register */
38#define PCH_ADDRESS_SIZE	0x20
39
40#define PCH_SPSR_TFD		0x000007C0
41#define PCH_SPSR_RFD		0x0000F800
42
43#define PCH_READABLE(x)		(((x) & PCH_SPSR_RFD)>>11)
44#define PCH_WRITABLE(x)		(((x) & PCH_SPSR_TFD)>>6)
45
46#define PCH_RX_THOLD		7
47#define PCH_RX_THOLD_MAX	15
48
49#define PCH_TX_THOLD		2
50
51#define PCH_MAX_BAUDRATE	5000000
52#define PCH_MAX_FIFO_DEPTH	16
53
54#define STATUS_RUNNING		1
55#define STATUS_EXITING		2
56#define PCH_SLEEP_TIME		10
57
58#define SSN_LOW			0x02U
59#define SSN_HIGH		0x03U
60#define SSN_NO_CONTROL		0x00U
61#define PCH_MAX_CS		0xFF
62#define PCI_DEVICE_ID_GE_SPI	0x8816
63
64#define SPCR_SPE_BIT		(1 << 0)
65#define SPCR_MSTR_BIT		(1 << 1)
66#define SPCR_LSBF_BIT		(1 << 4)
67#define SPCR_CPHA_BIT		(1 << 5)
68#define SPCR_CPOL_BIT		(1 << 6)
69#define SPCR_TFIE_BIT		(1 << 8)
70#define SPCR_RFIE_BIT		(1 << 9)
71#define SPCR_FIE_BIT		(1 << 10)
72#define SPCR_ORIE_BIT		(1 << 11)
73#define SPCR_MDFIE_BIT		(1 << 12)
74#define SPCR_FICLR_BIT		(1 << 24)
75#define SPSR_TFI_BIT		(1 << 0)
76#define SPSR_RFI_BIT		(1 << 1)
77#define SPSR_FI_BIT		(1 << 2)
78#define SPSR_ORF_BIT		(1 << 3)
79#define SPBRR_SIZE_BIT		(1 << 10)
80
81#define PCH_ALL			(SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|\
82				SPCR_ORIE_BIT|SPCR_MDFIE_BIT)
83
84#define SPCR_RFIC_FIELD		20
85#define SPCR_TFIC_FIELD		16
86
87#define MASK_SPBRR_SPBR_BITS	((1 << 10) - 1)
88#define MASK_RFIC_SPCR_BITS	(0xf << SPCR_RFIC_FIELD)
89#define MASK_TFIC_SPCR_BITS	(0xf << SPCR_TFIC_FIELD)
90
91#define PCH_CLOCK_HZ		50000000
92#define PCH_MAX_SPBR		1023
93
94/* Definition for ML7213/ML7223/ML7831 by LAPIS Semiconductor */
95#define PCI_VENDOR_ID_ROHM		0x10DB
96#define PCI_DEVICE_ID_ML7213_SPI	0x802c
97#define PCI_DEVICE_ID_ML7223_SPI	0x800F
98#define PCI_DEVICE_ID_ML7831_SPI	0x8816
99
100/*
101 * Set the number of SPI instance max
102 * Intel EG20T PCH :		1ch
103 * LAPIS Semiconductor ML7213 IOH :	2ch
104 * LAPIS Semiconductor ML7223 IOH :	1ch
105 * LAPIS Semiconductor ML7831 IOH :	1ch
106*/
107#define PCH_SPI_MAX_DEV			2
108
109#define PCH_BUF_SIZE		4096
110#define PCH_DMA_TRANS_SIZE	12
111
112static int use_dma = 1;
113
114struct pch_spi_dma_ctrl {
115	struct dma_async_tx_descriptor	*desc_tx;
116	struct dma_async_tx_descriptor	*desc_rx;
117	struct pch_dma_slave		param_tx;
118	struct pch_dma_slave		param_rx;
119	struct dma_chan		*chan_tx;
120	struct dma_chan		*chan_rx;
121	struct scatterlist		*sg_tx_p;
122	struct scatterlist		*sg_rx_p;
123	struct scatterlist		sg_tx;
124	struct scatterlist		sg_rx;
125	int				nent;
126	void				*tx_buf_virt;
127	void				*rx_buf_virt;
128	dma_addr_t			tx_buf_dma;
129	dma_addr_t			rx_buf_dma;
130};
131/**
132 * struct pch_spi_data - Holds the SPI channel specific details
133 * @io_remap_addr:		The remapped PCI base address
134 * @master:			Pointer to the SPI master structure
135 * @work:			Reference to work queue handler
136 * @wk:				Workqueue for carrying out execution of the
137 *				requests
138 * @wait:			Wait queue for waking up upon receiving an
139 *				interrupt.
140 * @transfer_complete:		Status of SPI Transfer
141 * @bcurrent_msg_processing:	Status flag for message processing
142 * @lock:			Lock for protecting this structure
143 * @queue:			SPI Message queue
144 * @status:			Status of the SPI driver
145 * @bpw_len:			Length of data to be transferred in bits per
146 *				word
147 * @transfer_active:		Flag showing active transfer
148 * @tx_index:			Transmit data count; for bookkeeping during
149 *				transfer
150 * @rx_index:			Receive data count; for bookkeeping during
151 *				transfer
152 * @tx_buff:			Buffer for data to be transmitted
153 * @rx_index:			Buffer for Received data
154 * @n_curnt_chip:		The chip number that this SPI driver currently
155 *				operates on
156 * @current_chip:		Reference to the current chip that this SPI
157 *				driver currently operates on
158 * @current_msg:		The current message that this SPI driver is
159 *				handling
160 * @cur_trans:			The current transfer that this SPI driver is
161 *				handling
162 * @board_dat:			Reference to the SPI device data structure
163 * @plat_dev:			platform_device structure
164 * @ch:				SPI channel number
165 * @irq_reg_sts:		Status of IRQ registration
166 */
167struct pch_spi_data {
168	void __iomem *io_remap_addr;
169	unsigned long io_base_addr;
170	struct spi_master *master;
171	struct work_struct work;
172	struct workqueue_struct *wk;
173	wait_queue_head_t wait;
174	u8 transfer_complete;
175	u8 bcurrent_msg_processing;
176	spinlock_t lock;
177	struct list_head queue;
178	u8 status;
179	u32 bpw_len;
180	u8 transfer_active;
181	u32 tx_index;
182	u32 rx_index;
183	u16 *pkt_tx_buff;
184	u16 *pkt_rx_buff;
185	u8 n_curnt_chip;
186	struct spi_device *current_chip;
187	struct spi_message *current_msg;
188	struct spi_transfer *cur_trans;
189	struct pch_spi_board_data *board_dat;
190	struct platform_device	*plat_dev;
191	int ch;
192	struct pch_spi_dma_ctrl dma;
193	int use_dma;
194	u8 irq_reg_sts;
195	int save_total_len;
196};
197
198/**
199 * struct pch_spi_board_data - Holds the SPI device specific details
200 * @pdev:		Pointer to the PCI device
201 * @suspend_sts:	Status of suspend
202 * @num:		The number of SPI device instance
203 */
204struct pch_spi_board_data {
205	struct pci_dev *pdev;
206	u8 suspend_sts;
207	int num;
208};
209
210struct pch_pd_dev_save {
211	int num;
212	struct platform_device *pd_save[PCH_SPI_MAX_DEV];
213	struct pch_spi_board_data *board_dat;
214};
215
216static const struct pci_device_id pch_spi_pcidev_id[] = {
217	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_GE_SPI),    1, },
218	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_SPI), 2, },
219	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_SPI), 1, },
220	{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_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 */
230static 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 */
241static 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
247static 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
255static 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 */
264static 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
270static 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		/* if transfer complete interrupt */
319		if (reg_spsr_val & SPSR_FI_BIT) {
320			if ((tx_index == bpw_len) && (rx_index == tx_index)) {
321				/* disable interrupts */
322				pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
323						   PCH_ALL);
324
325				/* transfer is completed;
326				   inform pch_spi_process_messages */
327				data->transfer_complete = true;
328				data->transfer_active = false;
329				wake_up(&data->wait);
330			} else {
331				dev_vdbg(&data->master->dev,
332					"%s : Transfer is not completed",
333					__func__);
334			}
335		}
336	}
337}
338
339/**
340 * pch_spi_handler() - Interrupt handler
341 * @irq:	The interrupt number.
342 * @dev_id:	Pointer to struct pch_spi_board_data.
343 */
344static irqreturn_t pch_spi_handler(int irq, void *dev_id)
345{
346	u32 reg_spsr_val;
347	void __iomem *spsr;
348	void __iomem *io_remap_addr;
349	irqreturn_t ret = IRQ_NONE;
350	struct pch_spi_data *data = dev_id;
351	struct pch_spi_board_data *board_dat = data->board_dat;
352
353	if (board_dat->suspend_sts) {
354		dev_dbg(&board_dat->pdev->dev,
355			"%s returning due to suspend\n", __func__);
356		return IRQ_NONE;
357	}
358
359	io_remap_addr = data->io_remap_addr;
360	spsr = io_remap_addr + PCH_SPSR;
361
362	reg_spsr_val = ioread32(spsr);
363
364	if (reg_spsr_val & SPSR_ORF_BIT) {
365		dev_err(&board_dat->pdev->dev, "%s Over run error\n", __func__);
366		if (data->current_msg->complete) {
367			data->transfer_complete = true;
368			data->current_msg->status = -EIO;
369			data->current_msg->complete(data->current_msg->context);
370			data->bcurrent_msg_processing = false;
371			data->current_msg = NULL;
372			data->cur_trans = NULL;
373		}
374	}
375
376	if (data->use_dma)
377		return IRQ_NONE;
378
379	/* Check if the interrupt is for SPI device */
380	if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
381		pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
382		ret = IRQ_HANDLED;
383	}
384
385	dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
386		__func__, ret);
387
388	return ret;
389}
390
391/**
392 * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
393 * @master:	Pointer to struct spi_master.
394 * @speed_hz:	Baud rate.
395 */
396static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
397{
398	u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
399
400	/* if baud rate is less than we can support limit it */
401	if (n_spbr > PCH_MAX_SPBR)
402		n_spbr = PCH_MAX_SPBR;
403
404	pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, MASK_SPBRR_SPBR_BITS);
405}
406
407/**
408 * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
409 * @master:		Pointer to struct spi_master.
410 * @bits_per_word:	Bits per word for SPI transfer.
411 */
412static void pch_spi_set_bits_per_word(struct spi_master *master,
413				      u8 bits_per_word)
414{
415	if (bits_per_word == 8)
416		pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
417	else
418		pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
419}
420
421/**
422 * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
423 * @spi:	Pointer to struct spi_device.
424 */
425static void pch_spi_setup_transfer(struct spi_device *spi)
426{
427	u32 flags = 0;
428
429	dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
430		__func__, pch_spi_readreg(spi->master, PCH_SPBRR),
431		spi->max_speed_hz);
432	pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
433
434	/* set bits per word */
435	pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
436
437	if (!(spi->mode & SPI_LSB_FIRST))
438		flags |= SPCR_LSBF_BIT;
439	if (spi->mode & SPI_CPOL)
440		flags |= SPCR_CPOL_BIT;
441	if (spi->mode & SPI_CPHA)
442		flags |= SPCR_CPHA_BIT;
443	pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
444			   (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
445
446	/* Clear the FIFO by toggling  FICLR to 1 and back to 0 */
447	pch_spi_clear_fifo(spi->master);
448}
449
450/**
451 * pch_spi_reset() - Clears SPI registers
452 * @master:	Pointer to struct spi_master.
453 */
454static void pch_spi_reset(struct spi_master *master)
455{
456	/* write 1 to reset SPI */
457	pch_spi_writereg(master, PCH_SRST, 0x1);
458
459	/* clear reset */
460	pch_spi_writereg(master, PCH_SRST, 0x0);
461}
462
463static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
464{
465
466	struct spi_transfer *transfer;
467	struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
468	int retval;
469	unsigned long flags;
470
471	spin_lock_irqsave(&data->lock, flags);
472	/* validate Tx/Rx buffers and Transfer length */
473	list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
474		if (!transfer->tx_buf && !transfer->rx_buf) {
475			dev_err(&pspi->dev,
476				"%s Tx and Rx buffer NULL\n", __func__);
477			retval = -EINVAL;
478			goto err_return_spinlock;
479		}
480
481		if (!transfer->len) {
482			dev_err(&pspi->dev, "%s Transfer length invalid\n",
483				__func__);
484			retval = -EINVAL;
485			goto err_return_spinlock;
486		}
487
488		dev_dbg(&pspi->dev,
489			"%s Tx/Rx buffer valid. Transfer length valid\n",
490			__func__);
491	}
492	spin_unlock_irqrestore(&data->lock, flags);
493
494	/* We won't process any messages if we have been asked to terminate */
495	if (data->status == STATUS_EXITING) {
496		dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
497		retval = -ESHUTDOWN;
498		goto err_out;
499	}
500
501	/* If suspended ,return -EINVAL */
502	if (data->board_dat->suspend_sts) {
503		dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
504		retval = -EINVAL;
505		goto err_out;
506	}
507
508	/* set status of message */
509	pmsg->actual_length = 0;
510	dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
511
512	pmsg->status = -EINPROGRESS;
513	spin_lock_irqsave(&data->lock, flags);
514	/* add message to queue */
515	list_add_tail(&pmsg->queue, &data->queue);
516	spin_unlock_irqrestore(&data->lock, flags);
517
518	dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
519
520	/* schedule work queue to run */
521	queue_work(data->wk, &data->work);
522	dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
523
524	retval = 0;
525
526err_out:
527	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
528	return retval;
529err_return_spinlock:
530	dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
531	spin_unlock_irqrestore(&data->lock, flags);
532	return retval;
533}
534
535static inline void pch_spi_select_chip(struct pch_spi_data *data,
536				       struct spi_device *pspi)
537{
538	if (data->current_chip != NULL) {
539		if (pspi->chip_select != data->n_curnt_chip) {
540			dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
541			data->current_chip = NULL;
542		}
543	}
544
545	data->current_chip = pspi;
546
547	data->n_curnt_chip = data->current_chip->chip_select;
548
549	dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
550	pch_spi_setup_transfer(pspi);
551}
552
553static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw)
554{
555	int size;
556	u32 n_writes;
557	int j;
558	struct spi_message *pmsg, *tmp;
559	const u8 *tx_buf;
560	const u16 *tx_sbuf;
561
562	/* set baud rate if needed */
563	if (data->cur_trans->speed_hz) {
564		dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
565		pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
566	}
567
568	/* set bits per word if needed */
569	if (data->cur_trans->bits_per_word &&
570	    (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
571		dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
572		pch_spi_set_bits_per_word(data->master,
573					  data->cur_trans->bits_per_word);
574		*bpw = data->cur_trans->bits_per_word;
575	} else {
576		*bpw = data->current_msg->spi->bits_per_word;
577	}
578
579	/* reset Tx/Rx index */
580	data->tx_index = 0;
581	data->rx_index = 0;
582
583	data->bpw_len = data->cur_trans->len / (*bpw / 8);
584
585	/* find alloc size */
586	size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
587
588	/* allocate memory for pkt_tx_buff & pkt_rx_buffer */
589	data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
590	if (data->pkt_tx_buff != NULL) {
591		data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
592		if (!data->pkt_rx_buff)
593			kfree(data->pkt_tx_buff);
594	}
595
596	if (!data->pkt_rx_buff) {
597		/* flush queue and set status of all transfers to -ENOMEM */
598		dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__);
599		list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
600			pmsg->status = -ENOMEM;
601
602			if (pmsg->complete)
603				pmsg->complete(pmsg->context);
604
605			/* delete from queue */
606			list_del_init(&pmsg->queue);
607		}
608		return;
609	}
610
611	/* copy Tx Data */
612	if (data->cur_trans->tx_buf != NULL) {
613		if (*bpw == 8) {
614			tx_buf = data->cur_trans->tx_buf;
615			for (j = 0; j < data->bpw_len; j++)
616				data->pkt_tx_buff[j] = *tx_buf++;
617		} else {
618			tx_sbuf = data->cur_trans->tx_buf;
619			for (j = 0; j < data->bpw_len; j++)
620				data->pkt_tx_buff[j] = *tx_sbuf++;
621		}
622	}
623
624	/* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
625	n_writes = data->bpw_len;
626	if (n_writes > PCH_MAX_FIFO_DEPTH)
627		n_writes = PCH_MAX_FIFO_DEPTH;
628
629	dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
630		"0x2 to SSNXCR\n", __func__);
631	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
632
633	for (j = 0; j < n_writes; j++)
634		pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
635
636	/* update tx_index */
637	data->tx_index = j;
638
639	/* reset transfer complete flag */
640	data->transfer_complete = false;
641	data->transfer_active = true;
642}
643
644static void pch_spi_nomore_transfer(struct pch_spi_data *data)
645{
646	struct spi_message *pmsg, *tmp;
647	dev_dbg(&data->master->dev, "%s called\n", __func__);
648	/* Invoke complete callback
649	 * [To the spi core..indicating end of transfer] */
650	data->current_msg->status = 0;
651
652	if (data->current_msg->complete) {
653		dev_dbg(&data->master->dev,
654			"%s:Invoking callback of SPI core\n", __func__);
655		data->current_msg->complete(data->current_msg->context);
656	}
657
658	/* update status in global variable */
659	data->bcurrent_msg_processing = false;
660
661	dev_dbg(&data->master->dev,
662		"%s:data->bcurrent_msg_processing = false\n", __func__);
663
664	data->current_msg = NULL;
665	data->cur_trans = NULL;
666
667	/* check if we have items in list and not suspending
668	 * return 1 if list empty */
669	if ((list_empty(&data->queue) == 0) &&
670	    (!data->board_dat->suspend_sts) &&
671	    (data->status != STATUS_EXITING)) {
672		/* We have some more work to do (either there is more tranint
673		 * bpw;sfer requests in the current message or there are
674		 *more messages)
675		 */
676		dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
677		queue_work(data->wk, &data->work);
678	} else if (data->board_dat->suspend_sts ||
679		   data->status == STATUS_EXITING) {
680		dev_dbg(&data->master->dev,
681			"%s suspend/remove initiated, flushing queue\n",
682			__func__);
683		list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
684			pmsg->status = -EIO;
685
686			if (pmsg->complete)
687				pmsg->complete(pmsg->context);
688
689			/* delete from queue */
690			list_del_init(&pmsg->queue);
691		}
692	}
693}
694
695static void pch_spi_set_ir(struct pch_spi_data *data)
696{
697	/* enable interrupts, set threshold, enable SPI */
698	if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH)
699		/* set receive threshold to PCH_RX_THOLD */
700		pch_spi_setclr_reg(data->master, PCH_SPCR,
701				   PCH_RX_THOLD << SPCR_RFIC_FIELD |
702				   SPCR_FIE_BIT | SPCR_RFIE_BIT |
703				   SPCR_ORIE_BIT | SPCR_SPE_BIT,
704				   MASK_RFIC_SPCR_BITS | PCH_ALL);
705	else
706		/* set receive threshold to maximum */
707		pch_spi_setclr_reg(data->master, PCH_SPCR,
708				   PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD |
709				   SPCR_FIE_BIT | SPCR_ORIE_BIT |
710				   SPCR_SPE_BIT,
711				   MASK_RFIC_SPCR_BITS | PCH_ALL);
712
713	/* Wait until the transfer completes; go to sleep after
714				 initiating the transfer. */
715	dev_dbg(&data->master->dev,
716		"%s:waiting for transfer to get over\n", __func__);
717
718	wait_event_interruptible(data->wait, data->transfer_complete);
719
720	/* clear all interrupts */
721	pch_spi_writereg(data->master, PCH_SPSR,
722			 pch_spi_readreg(data->master, PCH_SPSR));
723	/* Disable interrupts and SPI transfer */
724	pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL | SPCR_SPE_BIT);
725	/* clear FIFO */
726	pch_spi_clear_fifo(data->master);
727}
728
729static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
730{
731	int j;
732	u8 *rx_buf;
733	u16 *rx_sbuf;
734
735	/* copy Rx Data */
736	if (!data->cur_trans->rx_buf)
737		return;
738
739	if (bpw == 8) {
740		rx_buf = data->cur_trans->rx_buf;
741		for (j = 0; j < data->bpw_len; j++)
742			*rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
743	} else {
744		rx_sbuf = data->cur_trans->rx_buf;
745		for (j = 0; j < data->bpw_len; j++)
746			*rx_sbuf++ = data->pkt_rx_buff[j];
747	}
748}
749
750static void pch_spi_copy_rx_data_for_dma(struct pch_spi_data *data, int bpw)
751{
752	int j;
753	u8 *rx_buf;
754	u16 *rx_sbuf;
755	const u8 *rx_dma_buf;
756	const u16 *rx_dma_sbuf;
757
758	/* copy Rx Data */
759	if (!data->cur_trans->rx_buf)
760		return;
761
762	if (bpw == 8) {
763		rx_buf = data->cur_trans->rx_buf;
764		rx_dma_buf = data->dma.rx_buf_virt;
765		for (j = 0; j < data->bpw_len; j++)
766			*rx_buf++ = *rx_dma_buf++ & 0xFF;
767		data->cur_trans->rx_buf = rx_buf;
768	} else {
769		rx_sbuf = data->cur_trans->rx_buf;
770		rx_dma_sbuf = data->dma.rx_buf_virt;
771		for (j = 0; j < data->bpw_len; j++)
772			*rx_sbuf++ = *rx_dma_sbuf++;
773		data->cur_trans->rx_buf = rx_sbuf;
774	}
775}
776
777static int pch_spi_start_transfer(struct pch_spi_data *data)
778{
779	struct pch_spi_dma_ctrl *dma;
780	unsigned long flags;
781	int rtn;
782
783	dma = &data->dma;
784
785	spin_lock_irqsave(&data->lock, flags);
786
787	/* disable interrupts, SPI set enable */
788	pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_SPE_BIT, PCH_ALL);
789
790	spin_unlock_irqrestore(&data->lock, flags);
791
792	/* Wait until the transfer completes; go to sleep after
793				 initiating the transfer. */
794	dev_dbg(&data->master->dev,
795		"%s:waiting for transfer to get over\n", __func__);
796	rtn = wait_event_interruptible_timeout(data->wait,
797					       data->transfer_complete,
798					       msecs_to_jiffies(2 * HZ));
799	if (!rtn)
800		dev_err(&data->master->dev,
801			"%s wait-event timeout\n", __func__);
802
803	dma_sync_sg_for_cpu(&data->master->dev, dma->sg_rx_p, dma->nent,
804			    DMA_FROM_DEVICE);
805
806	dma_sync_sg_for_cpu(&data->master->dev, dma->sg_tx_p, dma->nent,
807			    DMA_FROM_DEVICE);
808	memset(data->dma.tx_buf_virt, 0, PAGE_SIZE);
809
810	async_tx_ack(dma->desc_rx);
811	async_tx_ack(dma->desc_tx);
812	kfree(dma->sg_tx_p);
813	kfree(dma->sg_rx_p);
814
815	spin_lock_irqsave(&data->lock, flags);
816
817	/* clear fifo threshold, disable interrupts, disable SPI transfer */
818	pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
819			   MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS | PCH_ALL |
820			   SPCR_SPE_BIT);
821	/* clear all interrupts */
822	pch_spi_writereg(data->master, PCH_SPSR,
823			 pch_spi_readreg(data->master, PCH_SPSR));
824	/* clear FIFO */
825	pch_spi_clear_fifo(data->master);
826
827	spin_unlock_irqrestore(&data->lock, flags);
828
829	return rtn;
830}
831
832static void pch_dma_rx_complete(void *arg)
833{
834	struct pch_spi_data *data = arg;
835
836	/* transfer is completed;inform pch_spi_process_messages_dma */
837	data->transfer_complete = true;
838	wake_up_interruptible(&data->wait);
839}
840
841static bool pch_spi_filter(struct dma_chan *chan, void *slave)
842{
843	struct pch_dma_slave *param = slave;
844
845	if ((chan->chan_id == param->chan_id) &&
846	    (param->dma_dev == chan->device->dev)) {
847		chan->private = param;
848		return true;
849	} else {
850		return false;
851	}
852}
853
854static void pch_spi_request_dma(struct pch_spi_data *data, int bpw)
855{
856	dma_cap_mask_t mask;
857	struct dma_chan *chan;
858	struct pci_dev *dma_dev;
859	struct pch_dma_slave *param;
860	struct pch_spi_dma_ctrl *dma;
861	unsigned int width;
862
863	if (bpw == 8)
864		width = PCH_DMA_WIDTH_1_BYTE;
865	else
866		width = PCH_DMA_WIDTH_2_BYTES;
867
868	dma = &data->dma;
869	dma_cap_zero(mask);
870	dma_cap_set(DMA_SLAVE, mask);
871
872	/* Get DMA's dev information */
873	dma_dev = pci_get_slot(data->board_dat->pdev->bus,
874			PCI_DEVFN(PCI_SLOT(data->board_dat->pdev->devfn), 0));
875
876	/* Set Tx DMA */
877	param = &dma->param_tx;
878	param->dma_dev = &dma_dev->dev;
879	param->chan_id = data->ch * 2; /* Tx = 0, 2 */;
880	param->tx_reg = data->io_base_addr + PCH_SPDWR;
881	param->width = width;
882	chan = dma_request_channel(mask, pch_spi_filter, param);
883	if (!chan) {
884		dev_err(&data->master->dev,
885			"ERROR: dma_request_channel FAILS(Tx)\n");
886		data->use_dma = 0;
887		return;
888	}
889	dma->chan_tx = chan;
890
891	/* Set Rx DMA */
892	param = &dma->param_rx;
893	param->dma_dev = &dma_dev->dev;
894	param->chan_id = data->ch * 2 + 1; /* Rx = Tx + 1 */;
895	param->rx_reg = data->io_base_addr + PCH_SPDRR;
896	param->width = width;
897	chan = dma_request_channel(mask, pch_spi_filter, param);
898	if (!chan) {
899		dev_err(&data->master->dev,
900			"ERROR: dma_request_channel FAILS(Rx)\n");
901		dma_release_channel(dma->chan_tx);
902		dma->chan_tx = NULL;
903		data->use_dma = 0;
904		return;
905	}
906	dma->chan_rx = chan;
907}
908
909static void pch_spi_release_dma(struct pch_spi_data *data)
910{
911	struct pch_spi_dma_ctrl *dma;
912
913	dma = &data->dma;
914	if (dma->chan_tx) {
915		dma_release_channel(dma->chan_tx);
916		dma->chan_tx = NULL;
917	}
918	if (dma->chan_rx) {
919		dma_release_channel(dma->chan_rx);
920		dma->chan_rx = NULL;
921	}
922	return;
923}
924
925static void pch_spi_handle_dma(struct pch_spi_data *data, int *bpw)
926{
927	const u8 *tx_buf;
928	const u16 *tx_sbuf;
929	u8 *tx_dma_buf;
930	u16 *tx_dma_sbuf;
931	struct scatterlist *sg;
932	struct dma_async_tx_descriptor *desc_tx;
933	struct dma_async_tx_descriptor *desc_rx;
934	int num;
935	int i;
936	int size;
937	int rem;
938	int head;
939	unsigned long flags;
940	struct pch_spi_dma_ctrl *dma;
941
942	dma = &data->dma;
943
944	/* set baud rate if needed */
945	if (data->cur_trans->speed_hz) {
946		dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
947		spin_lock_irqsave(&data->lock, flags);
948		pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
949		spin_unlock_irqrestore(&data->lock, flags);
950	}
951
952	/* set bits per word if needed */
953	if (data->cur_trans->bits_per_word &&
954	    (data->current_msg->spi->bits_per_word !=
955	     data->cur_trans->bits_per_word)) {
956		dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
957		spin_lock_irqsave(&data->lock, flags);
958		pch_spi_set_bits_per_word(data->master,
959					  data->cur_trans->bits_per_word);
960		spin_unlock_irqrestore(&data->lock, flags);
961		*bpw = data->cur_trans->bits_per_word;
962	} else {
963		*bpw = data->current_msg->spi->bits_per_word;
964	}
965	data->bpw_len = data->cur_trans->len / (*bpw / 8);
966
967	if (data->bpw_len > PCH_BUF_SIZE) {
968		data->bpw_len = PCH_BUF_SIZE;
969		data->cur_trans->len -= PCH_BUF_SIZE;
970	}
971
972	/* copy Tx Data */
973	if (data->cur_trans->tx_buf != NULL) {
974		if (*bpw == 8) {
975			tx_buf = data->cur_trans->tx_buf;
976			tx_dma_buf = dma->tx_buf_virt;
977			for (i = 0; i < data->bpw_len; i++)
978				*tx_dma_buf++ = *tx_buf++;
979		} else {
980			tx_sbuf = data->cur_trans->tx_buf;
981			tx_dma_sbuf = dma->tx_buf_virt;
982			for (i = 0; i < data->bpw_len; i++)
983				*tx_dma_sbuf++ = *tx_sbuf++;
984		}
985	}
986
987	/* Calculate Rx parameter for DMA transmitting */
988	if (data->bpw_len > PCH_DMA_TRANS_SIZE) {
989		if (data->bpw_len % PCH_DMA_TRANS_SIZE) {
990			num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
991			rem = data->bpw_len % PCH_DMA_TRANS_SIZE;
992		} else {
993			num = data->bpw_len / PCH_DMA_TRANS_SIZE;
994			rem = PCH_DMA_TRANS_SIZE;
995		}
996		size = PCH_DMA_TRANS_SIZE;
997	} else {
998		num = 1;
999		size = data->bpw_len;
1000		rem = data->bpw_len;
1001	}
1002	dev_dbg(&data->master->dev, "%s num=%d size=%d rem=%d\n",
1003		__func__, num, size, rem);
1004	spin_lock_irqsave(&data->lock, flags);
1005
1006	/* set receive fifo threshold and transmit fifo threshold */
1007	pch_spi_setclr_reg(data->master, PCH_SPCR,
1008			   ((size - 1) << SPCR_RFIC_FIELD) |
1009			   (PCH_TX_THOLD << SPCR_TFIC_FIELD),
1010			   MASK_RFIC_SPCR_BITS | MASK_TFIC_SPCR_BITS);
1011
1012	spin_unlock_irqrestore(&data->lock, flags);
1013
1014	/* RX */
1015	dma->sg_rx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
1016	sg_init_table(dma->sg_rx_p, num); /* Initialize SG table */
1017	/* offset, length setting */
1018	sg = dma->sg_rx_p;
1019	for (i = 0; i < num; i++, sg++) {
1020		if (i == (num - 2)) {
1021			sg->offset = size * i;
1022			sg->offset = sg->offset * (*bpw / 8);
1023			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), rem,
1024				    sg->offset);
1025			sg_dma_len(sg) = rem;
1026		} else if (i == (num - 1)) {
1027			sg->offset = size * (i - 1) + rem;
1028			sg->offset = sg->offset * (*bpw / 8);
1029			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1030				    sg->offset);
1031			sg_dma_len(sg) = size;
1032		} else {
1033			sg->offset = size * i;
1034			sg->offset = sg->offset * (*bpw / 8);
1035			sg_set_page(sg, virt_to_page(dma->rx_buf_virt), size,
1036				    sg->offset);
1037			sg_dma_len(sg) = size;
1038		}
1039		sg_dma_address(sg) = dma->rx_buf_dma + sg->offset;
1040	}
1041	sg = dma->sg_rx_p;
1042	desc_rx = dmaengine_prep_slave_sg(dma->chan_rx, sg,
1043					num, DMA_DEV_TO_MEM,
1044					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1045	if (!desc_rx) {
1046		dev_err(&data->master->dev,
1047			"%s:dmaengine_prep_slave_sg Failed\n", __func__);
1048		return;
1049	}
1050	dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_FROM_DEVICE);
1051	desc_rx->callback = pch_dma_rx_complete;
1052	desc_rx->callback_param = data;
1053	dma->nent = num;
1054	dma->desc_rx = desc_rx;
1055
1056	/* Calculate Tx parameter for DMA transmitting */
1057	if (data->bpw_len > PCH_MAX_FIFO_DEPTH) {
1058		head = PCH_MAX_FIFO_DEPTH - PCH_DMA_TRANS_SIZE;
1059		if (data->bpw_len % PCH_DMA_TRANS_SIZE > 4) {
1060			num = data->bpw_len / PCH_DMA_TRANS_SIZE + 1;
1061			rem = data->bpw_len % PCH_DMA_TRANS_SIZE - head;
1062		} else {
1063			num = data->bpw_len / PCH_DMA_TRANS_SIZE;
1064			rem = data->bpw_len % PCH_DMA_TRANS_SIZE +
1065			      PCH_DMA_TRANS_SIZE - head;
1066		}
1067		size = PCH_DMA_TRANS_SIZE;
1068	} else {
1069		num = 1;
1070		size = data->bpw_len;
1071		rem = data->bpw_len;
1072		head = 0;
1073	}
1074
1075	dma->sg_tx_p = kzalloc(sizeof(struct scatterlist)*num, GFP_ATOMIC);
1076	sg_init_table(dma->sg_tx_p, num); /* Initialize SG table */
1077	/* offset, length setting */
1078	sg = dma->sg_tx_p;
1079	for (i = 0; i < num; i++, sg++) {
1080		if (i == 0) {
1081			sg->offset = 0;
1082			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size + head,
1083				    sg->offset);
1084			sg_dma_len(sg) = size + head;
1085		} else if (i == (num - 1)) {
1086			sg->offset = head + size * i;
1087			sg->offset = sg->offset * (*bpw / 8);
1088			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), rem,
1089				    sg->offset);
1090			sg_dma_len(sg) = rem;
1091		} else {
1092			sg->offset = head + size * i;
1093			sg->offset = sg->offset * (*bpw / 8);
1094			sg_set_page(sg, virt_to_page(dma->tx_buf_virt), size,
1095				    sg->offset);
1096			sg_dma_len(sg) = size;
1097		}
1098		sg_dma_address(sg) = dma->tx_buf_dma + sg->offset;
1099	}
1100	sg = dma->sg_tx_p;
1101	desc_tx = dmaengine_prep_slave_sg(dma->chan_tx,
1102					sg, num, DMA_MEM_TO_DEV,
1103					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1104	if (!desc_tx) {
1105		dev_err(&data->master->dev,
1106			"%s:dmaengine_prep_slave_sg Failed\n", __func__);
1107		return;
1108	}
1109	dma_sync_sg_for_device(&data->master->dev, sg, num, DMA_TO_DEVICE);
1110	desc_tx->callback = NULL;
1111	desc_tx->callback_param = data;
1112	dma->nent = num;
1113	dma->desc_tx = desc_tx;
1114
1115	dev_dbg(&data->master->dev, "%s:Pulling down SSN low - writing 0x2 to SSNXCR\n", __func__);
1116
1117	spin_lock_irqsave(&data->lock, flags);
1118	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
1119	desc_rx->tx_submit(desc_rx);
1120	desc_tx->tx_submit(desc_tx);
1121	spin_unlock_irqrestore(&data->lock, flags);
1122
1123	/* reset transfer complete flag */
1124	data->transfer_complete = false;
1125}
1126
1127static void pch_spi_process_messages(struct work_struct *pwork)
1128{
1129	struct spi_message *pmsg, *tmp;
1130	struct pch_spi_data *data;
1131	int bpw;
1132
1133	data = container_of(pwork, struct pch_spi_data, work);
1134	dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
1135
1136	spin_lock(&data->lock);
1137	/* check if suspend has been initiated;if yes flush queue */
1138	if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
1139		dev_dbg(&data->master->dev,
1140			"%s suspend/remove initiated, flushing queue\n", __func__);
1141		list_for_each_entry_safe(pmsg, tmp, data->queue.next, queue) {
1142			pmsg->status = -EIO;
1143
1144			if (pmsg->complete) {
1145				spin_unlock(&data->lock);
1146				pmsg->complete(pmsg->context);
1147				spin_lock(&data->lock);
1148			}
1149
1150			/* delete from queue */
1151			list_del_init(&pmsg->queue);
1152		}
1153
1154		spin_unlock(&data->lock);
1155		return;
1156	}
1157
1158	data->bcurrent_msg_processing = true;
1159	dev_dbg(&data->master->dev,
1160		"%s Set data->bcurrent_msg_processing= true\n", __func__);
1161
1162	/* Get the message from the queue and delete it from there. */
1163	data->current_msg = list_entry(data->queue.next, struct spi_message,
1164					queue);
1165
1166	list_del_init(&data->current_msg->queue);
1167
1168	data->current_msg->status = 0;
1169
1170	pch_spi_select_chip(data, data->current_msg->spi);
1171
1172	spin_unlock(&data->lock);
1173
1174	if (data->use_dma)
1175		pch_spi_request_dma(data,
1176				    data->current_msg->spi->bits_per_word);
1177	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
1178	do {
1179		int cnt;
1180		/* If we are already processing a message get the next
1181		transfer structure from the message otherwise retrieve
1182		the 1st transfer request from the message. */
1183		spin_lock(&data->lock);
1184		if (data->cur_trans == NULL) {
1185			data->cur_trans =
1186				list_entry(data->current_msg->transfers.next,
1187					   struct spi_transfer, transfer_list);
1188			dev_dbg(&data->master->dev, "%s "
1189				":Getting 1st transfer message\n", __func__);
1190		} else {
1191			data->cur_trans =
1192				list_entry(data->cur_trans->transfer_list.next,
1193					   struct spi_transfer, transfer_list);
1194			dev_dbg(&data->master->dev, "%s "
1195				":Getting next transfer message\n", __func__);
1196		}
1197		spin_unlock(&data->lock);
1198
1199		if (!data->cur_trans->len)
1200			goto out;
1201		cnt = (data->cur_trans->len - 1) / PCH_BUF_SIZE + 1;
1202		data->save_total_len = data->cur_trans->len;
1203		if (data->use_dma) {
1204			int i;
1205			char *save_rx_buf = data->cur_trans->rx_buf;
1206			for (i = 0; i < cnt; i ++) {
1207				pch_spi_handle_dma(data, &bpw);
1208				if (!pch_spi_start_transfer(data)) {
1209					data->transfer_complete = true;
1210					data->current_msg->status = -EIO;
1211					data->current_msg->complete
1212						   (data->current_msg->context);
1213					data->bcurrent_msg_processing = false;
1214					data->current_msg = NULL;
1215					data->cur_trans = NULL;
1216					goto out;
1217				}
1218				pch_spi_copy_rx_data_for_dma(data, bpw);
1219			}
1220			data->cur_trans->rx_buf = save_rx_buf;
1221		} else {
1222			pch_spi_set_tx(data, &bpw);
1223			pch_spi_set_ir(data);
1224			pch_spi_copy_rx_data(data, bpw);
1225			kfree(data->pkt_rx_buff);
1226			data->pkt_rx_buff = NULL;
1227			kfree(data->pkt_tx_buff);
1228			data->pkt_tx_buff = NULL;
1229		}
1230		/* increment message count */
1231		data->cur_trans->len = data->save_total_len;
1232		data->current_msg->actual_length += data->cur_trans->len;
1233
1234		dev_dbg(&data->master->dev,
1235			"%s:data->current_msg->actual_length=%d\n",
1236			__func__, data->current_msg->actual_length);
1237
1238		/* check for delay */
1239		if (data->cur_trans->delay_usecs) {
1240			dev_dbg(&data->master->dev, "%s:"
1241				"delay in usec=%d\n", __func__,
1242				data->cur_trans->delay_usecs);
1243			udelay(data->cur_trans->delay_usecs);
1244		}
1245
1246		spin_lock(&data->lock);
1247
1248		/* No more transfer in this message. */
1249		if ((data->cur_trans->transfer_list.next) ==
1250		    &(data->current_msg->transfers)) {
1251			pch_spi_nomore_transfer(data);
1252		}
1253
1254		spin_unlock(&data->lock);
1255
1256	} while (data->cur_trans != NULL);
1257
1258out:
1259	pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH);
1260	if (data->use_dma)
1261		pch_spi_release_dma(data);
1262}
1263
1264static void pch_spi_free_resources(struct pch_spi_board_data *board_dat,
1265				   struct pch_spi_data *data)
1266{
1267	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1268
1269	/* free workqueue */
1270	if (data->wk != NULL) {
1271		destroy_workqueue(data->wk);
1272		data->wk = NULL;
1273		dev_dbg(&board_dat->pdev->dev,
1274			"%s destroy_workqueue invoked successfully\n",
1275			__func__);
1276	}
1277}
1278
1279static int pch_spi_get_resources(struct pch_spi_board_data *board_dat,
1280				 struct pch_spi_data *data)
1281{
1282	int retval = 0;
1283
1284	dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
1285
1286	/* create workqueue */
1287	data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
1288	if (!data->wk) {
1289		dev_err(&board_dat->pdev->dev,
1290			"%s create_singlet hread_workqueue failed\n", __func__);
1291		retval = -EBUSY;
1292		goto err_return;
1293	}
1294
1295	/* reset PCH SPI h/w */
1296	pch_spi_reset(data->master);
1297	dev_dbg(&board_dat->pdev->dev,
1298		"%s pch_spi_reset invoked successfully\n", __func__);
1299
1300	dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
1301
1302err_return:
1303	if (retval != 0) {
1304		dev_err(&board_dat->pdev->dev,
1305			"%s FAIL:invoking pch_spi_free_resources\n", __func__);
1306		pch_spi_free_resources(board_dat, data);
1307	}
1308
1309	dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
1310
1311	return retval;
1312}
1313
1314static void pch_free_dma_buf(struct pch_spi_board_data *board_dat,
1315			     struct pch_spi_data *data)
1316{
1317	struct pch_spi_dma_ctrl *dma;
1318
1319	dma = &data->dma;
1320	if (dma->tx_buf_dma)
1321		dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1322				  dma->tx_buf_virt, dma->tx_buf_dma);
1323	if (dma->rx_buf_dma)
1324		dma_free_coherent(&board_dat->pdev->dev, PCH_BUF_SIZE,
1325				  dma->rx_buf_virt, dma->rx_buf_dma);
1326	return;
1327}
1328
1329static void pch_alloc_dma_buf(struct pch_spi_board_data *board_dat,
1330			      struct pch_spi_data *data)
1331{
1332	struct pch_spi_dma_ctrl *dma;
1333
1334	dma = &data->dma;
1335	/* Get Consistent memory for Tx DMA */
1336	dma->tx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1337				PCH_BUF_SIZE, &dma->tx_buf_dma, GFP_KERNEL);
1338	/* Get Consistent memory for Rx DMA */
1339	dma->rx_buf_virt = dma_alloc_coherent(&board_dat->pdev->dev,
1340				PCH_BUF_SIZE, &dma->rx_buf_dma, GFP_KERNEL);
1341}
1342
1343static int pch_spi_pd_probe(struct platform_device *plat_dev)
1344{
1345	int ret;
1346	struct spi_master *master;
1347	struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1348	struct pch_spi_data *data;
1349
1350	dev_dbg(&plat_dev->dev, "%s:debug\n", __func__);
1351
1352	master = spi_alloc_master(&board_dat->pdev->dev,
1353				  sizeof(struct pch_spi_data));
1354	if (!master) {
1355		dev_err(&plat_dev->dev, "spi_alloc_master[%d] failed.\n",
1356			plat_dev->id);
1357		return -ENOMEM;
1358	}
1359
1360	data = spi_master_get_devdata(master);
1361	data->master = master;
1362
1363	platform_set_drvdata(plat_dev, data);
1364
1365	/* baseaddress + address offset) */
1366	data->io_base_addr = pci_resource_start(board_dat->pdev, 1) +
1367					 PCH_ADDRESS_SIZE * plat_dev->id;
1368	data->io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
1369	if (!data->io_remap_addr) {
1370		dev_err(&plat_dev->dev, "%s pci_iomap failed\n", __func__);
1371		ret = -ENOMEM;
1372		goto err_pci_iomap;
1373	}
1374	data->io_remap_addr += PCH_ADDRESS_SIZE * plat_dev->id;
1375
1376	dev_dbg(&plat_dev->dev, "[ch%d] remap_addr=%p\n",
1377		plat_dev->id, data->io_remap_addr);
1378
1379	/* initialize members of SPI master */
1380	master->num_chipselect = PCH_MAX_CS;
1381	master->transfer = pch_spi_transfer;
1382	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1383	master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
1384	master->max_speed_hz = PCH_MAX_BAUDRATE;
1385
1386	data->board_dat = board_dat;
1387	data->plat_dev = plat_dev;
1388	data->n_curnt_chip = 255;
1389	data->status = STATUS_RUNNING;
1390	data->ch = plat_dev->id;
1391	data->use_dma = use_dma;
1392
1393	INIT_LIST_HEAD(&data->queue);
1394	spin_lock_init(&data->lock);
1395	INIT_WORK(&data->work, pch_spi_process_messages);
1396	init_waitqueue_head(&data->wait);
1397
1398	ret = pch_spi_get_resources(board_dat, data);
1399	if (ret) {
1400		dev_err(&plat_dev->dev, "%s fail(retval=%d)\n", __func__, ret);
1401		goto err_spi_get_resources;
1402	}
1403
1404	ret = request_irq(board_dat->pdev->irq, pch_spi_handler,
1405			  IRQF_SHARED, KBUILD_MODNAME, data);
1406	if (ret) {
1407		dev_err(&plat_dev->dev,
1408			"%s request_irq failed\n", __func__);
1409		goto err_request_irq;
1410	}
1411	data->irq_reg_sts = true;
1412
1413	pch_spi_set_master_mode(master);
1414
1415	if (use_dma) {
1416		dev_info(&plat_dev->dev, "Use DMA for data transfers\n");
1417		pch_alloc_dma_buf(board_dat, data);
1418	}
1419
1420	ret = spi_register_master(master);
1421	if (ret != 0) {
1422		dev_err(&plat_dev->dev,
1423			"%s spi_register_master FAILED\n", __func__);
1424		goto err_spi_register_master;
1425	}
1426
1427	return 0;
1428
1429err_spi_register_master:
1430	pch_free_dma_buf(board_dat, data);
1431	free_irq(board_dat->pdev->irq, data);
1432err_request_irq:
1433	pch_spi_free_resources(board_dat, data);
1434err_spi_get_resources:
1435	pci_iounmap(board_dat->pdev, data->io_remap_addr);
1436err_pci_iomap:
1437	spi_master_put(master);
1438
1439	return ret;
1440}
1441
1442static int pch_spi_pd_remove(struct platform_device *plat_dev)
1443{
1444	struct pch_spi_board_data *board_dat = dev_get_platdata(&plat_dev->dev);
1445	struct pch_spi_data *data = platform_get_drvdata(plat_dev);
1446	int count;
1447	unsigned long flags;
1448
1449	dev_dbg(&plat_dev->dev, "%s:[ch%d] irq=%d\n",
1450		__func__, plat_dev->id, board_dat->pdev->irq);
1451
1452	if (use_dma)
1453		pch_free_dma_buf(board_dat, data);
1454
1455	/* check for any pending messages; no action is taken if the queue
1456	 * is still full; but at least we tried.  Unload anyway */
1457	count = 500;
1458	spin_lock_irqsave(&data->lock, flags);
1459	data->status = STATUS_EXITING;
1460	while ((list_empty(&data->queue) == 0) && --count) {
1461		dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
1462			__func__);
1463		spin_unlock_irqrestore(&data->lock, flags);
1464		msleep(PCH_SLEEP_TIME);
1465		spin_lock_irqsave(&data->lock, flags);
1466	}
1467	spin_unlock_irqrestore(&data->lock, flags);
1468
1469	pch_spi_free_resources(board_dat, data);
1470	/* disable interrupts & free IRQ */
1471	if (data->irq_reg_sts) {
1472		/* disable interrupts */
1473		pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1474		data->irq_reg_sts = false;
1475		free_irq(board_dat->pdev->irq, data);
1476	}
1477
1478	pci_iounmap(board_dat->pdev, data->io_remap_addr);
1479	spi_unregister_master(data->master);
1480
1481	return 0;
1482}
1483#ifdef CONFIG_PM
1484static int pch_spi_pd_suspend(struct platform_device *pd_dev,
1485			      pm_message_t state)
1486{
1487	u8 count;
1488	struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1489	struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1490
1491	dev_dbg(&pd_dev->dev, "%s ENTRY\n", __func__);
1492
1493	if (!board_dat) {
1494		dev_err(&pd_dev->dev,
1495			"%s pci_get_drvdata returned NULL\n", __func__);
1496		return -EFAULT;
1497	}
1498
1499	/* check if the current message is processed:
1500	   Only after thats done the transfer will be suspended */
1501	count = 255;
1502	while ((--count) > 0) {
1503		if (!(data->bcurrent_msg_processing))
1504			break;
1505		msleep(PCH_SLEEP_TIME);
1506	}
1507
1508	/* Free IRQ */
1509	if (data->irq_reg_sts) {
1510		/* disable all interrupts */
1511		pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
1512		pch_spi_reset(data->master);
1513		free_irq(board_dat->pdev->irq, data);
1514
1515		data->irq_reg_sts = false;
1516		dev_dbg(&pd_dev->dev,
1517			"%s free_irq invoked successfully.\n", __func__);
1518	}
1519
1520	return 0;
1521}
1522
1523static int pch_spi_pd_resume(struct platform_device *pd_dev)
1524{
1525	struct pch_spi_board_data *board_dat = dev_get_platdata(&pd_dev->dev);
1526	struct pch_spi_data *data = platform_get_drvdata(pd_dev);
1527	int retval;
1528
1529	if (!board_dat) {
1530		dev_err(&pd_dev->dev,
1531			"%s pci_get_drvdata returned NULL\n", __func__);
1532		return -EFAULT;
1533	}
1534
1535	if (!data->irq_reg_sts) {
1536		/* register IRQ */
1537		retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
1538				     IRQF_SHARED, KBUILD_MODNAME, data);
1539		if (retval < 0) {
1540			dev_err(&pd_dev->dev,
1541				"%s request_irq failed\n", __func__);
1542			return retval;
1543		}
1544
1545		/* reset PCH SPI h/w */
1546		pch_spi_reset(data->master);
1547		pch_spi_set_master_mode(data->master);
1548		data->irq_reg_sts = true;
1549	}
1550	return 0;
1551}
1552#else
1553#define pch_spi_pd_suspend NULL
1554#define pch_spi_pd_resume NULL
1555#endif
1556
1557static struct platform_driver pch_spi_pd_driver = {
1558	.driver = {
1559		.name = "pch-spi",
1560	},
1561	.probe = pch_spi_pd_probe,
1562	.remove = pch_spi_pd_remove,
1563	.suspend = pch_spi_pd_suspend,
1564	.resume = pch_spi_pd_resume
1565};
1566
1567static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1568{
1569	struct pch_spi_board_data *board_dat;
1570	struct platform_device *pd_dev = NULL;
1571	int retval;
1572	int i;
1573	struct pch_pd_dev_save *pd_dev_save;
1574
1575	pd_dev_save = kzalloc(sizeof(struct pch_pd_dev_save), GFP_KERNEL);
1576	if (!pd_dev_save)
1577		return -ENOMEM;
1578
1579	board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
1580	if (!board_dat) {
1581		retval = -ENOMEM;
1582		goto err_no_mem;
1583	}
1584
1585	retval = pci_request_regions(pdev, KBUILD_MODNAME);
1586	if (retval) {
1587		dev_err(&pdev->dev, "%s request_region failed\n", __func__);
1588		goto pci_request_regions;
1589	}
1590
1591	board_dat->pdev = pdev;
1592	board_dat->num = id->driver_data;
1593	pd_dev_save->num = id->driver_data;
1594	pd_dev_save->board_dat = board_dat;
1595
1596	retval = pci_enable_device(pdev);
1597	if (retval) {
1598		dev_err(&pdev->dev, "%s pci_enable_device failed\n", __func__);
1599		goto pci_enable_device;
1600	}
1601
1602	for (i = 0; i < board_dat->num; i++) {
1603		pd_dev = platform_device_alloc("pch-spi", i);
1604		if (!pd_dev) {
1605			dev_err(&pdev->dev, "platform_device_alloc failed\n");
1606			retval = -ENOMEM;
1607			goto err_platform_device;
1608		}
1609		pd_dev_save->pd_save[i] = pd_dev;
1610		pd_dev->dev.parent = &pdev->dev;
1611
1612		retval = platform_device_add_data(pd_dev, board_dat,
1613						  sizeof(*board_dat));
1614		if (retval) {
1615			dev_err(&pdev->dev,
1616				"platform_device_add_data failed\n");
1617			platform_device_put(pd_dev);
1618			goto err_platform_device;
1619		}
1620
1621		retval = platform_device_add(pd_dev);
1622		if (retval) {
1623			dev_err(&pdev->dev, "platform_device_add failed\n");
1624			platform_device_put(pd_dev);
1625			goto err_platform_device;
1626		}
1627	}
1628
1629	pci_set_drvdata(pdev, pd_dev_save);
1630
1631	return 0;
1632
1633err_platform_device:
1634	while (--i >= 0)
1635		platform_device_unregister(pd_dev_save->pd_save[i]);
1636	pci_disable_device(pdev);
1637pci_enable_device:
1638	pci_release_regions(pdev);
1639pci_request_regions:
1640	kfree(board_dat);
1641err_no_mem:
1642	kfree(pd_dev_save);
1643
1644	return retval;
1645}
1646
1647static void pch_spi_remove(struct pci_dev *pdev)
1648{
1649	int i;
1650	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1651
1652	dev_dbg(&pdev->dev, "%s ENTRY:pdev=%p\n", __func__, pdev);
1653
1654	for (i = 0; i < pd_dev_save->num; i++)
1655		platform_device_unregister(pd_dev_save->pd_save[i]);
1656
1657	pci_disable_device(pdev);
1658	pci_release_regions(pdev);
1659	kfree(pd_dev_save->board_dat);
1660	kfree(pd_dev_save);
1661}
1662
1663#ifdef CONFIG_PM
1664static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
1665{
1666	int retval;
1667	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1668
1669	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1670
1671	pd_dev_save->board_dat->suspend_sts = true;
1672
1673	/* save config space */
1674	retval = pci_save_state(pdev);
1675	if (retval == 0) {
1676		pci_enable_wake(pdev, PCI_D3hot, 0);
1677		pci_disable_device(pdev);
1678		pci_set_power_state(pdev, PCI_D3hot);
1679	} else {
1680		dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
1681	}
1682
1683	return retval;
1684}
1685
1686static int pch_spi_resume(struct pci_dev *pdev)
1687{
1688	int retval;
1689	struct pch_pd_dev_save *pd_dev_save = pci_get_drvdata(pdev);
1690	dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1691
1692	pci_set_power_state(pdev, PCI_D0);
1693	pci_restore_state(pdev);
1694
1695	retval = pci_enable_device(pdev);
1696	if (retval < 0) {
1697		dev_err(&pdev->dev,
1698			"%s pci_enable_device failed\n", __func__);
1699	} else {
1700		pci_enable_wake(pdev, PCI_D3hot, 0);
1701
1702		/* set suspend status to false */
1703		pd_dev_save->board_dat->suspend_sts = false;
1704	}
1705
1706	return retval;
1707}
1708#else
1709#define pch_spi_suspend NULL
1710#define pch_spi_resume NULL
1711
1712#endif
1713
1714static struct pci_driver pch_spi_pcidev_driver = {
1715	.name = "pch_spi",
1716	.id_table = pch_spi_pcidev_id,
1717	.probe = pch_spi_probe,
1718	.remove = pch_spi_remove,
1719	.suspend = pch_spi_suspend,
1720	.resume = pch_spi_resume,
1721};
1722
1723static int __init pch_spi_init(void)
1724{
1725	int ret;
1726	ret = platform_driver_register(&pch_spi_pd_driver);
1727	if (ret)
1728		return ret;
1729
1730	ret = pci_register_driver(&pch_spi_pcidev_driver);
1731	if (ret) {
1732		platform_driver_unregister(&pch_spi_pd_driver);
1733		return ret;
1734	}
1735
1736	return 0;
1737}
1738module_init(pch_spi_init);
1739
1740static void __exit pch_spi_exit(void)
1741{
1742	pci_unregister_driver(&pch_spi_pcidev_driver);
1743	platform_driver_unregister(&pch_spi_pd_driver);
1744}
1745module_exit(pch_spi_exit);
1746
1747module_param(use_dma, int, 0644);
1748MODULE_PARM_DESC(use_dma,
1749		 "to use DMA for data transfers pass 1 else 0; default 1");
1750
1751MODULE_LICENSE("GPL");
1752MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semiconductor ML7xxx IOH SPI Driver");
1753MODULE_DEVICE_TABLE(pci, pch_spi_pcidev_id);
1754
1755