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path: root/drivers/spi/spi-topcliff-pch.c
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-rw-r--r--drivers/spi/spi-topcliff-pch.c1303
1 files changed, 1303 insertions, 0 deletions
diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c
new file mode 100644
index 000000000000..79e48d451137
--- /dev/null
+++ b/drivers/spi/spi-topcliff-pch.c
@@ -0,0 +1,1303 @@
1/*
2 * SPI bus driver for the Topcliff PCH used by Intel SoCs
3 *
4 * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
18 */
19
20#include <linux/delay.h>
21#include <linux/pci.h>
22#include <linux/wait.h>
23#include <linux/spi/spi.h>
24#include <linux/interrupt.h>
25#include <linux/sched.h>
26#include <linux/spi/spidev.h>
27#include <linux/module.h>
28#include <linux/device.h>
29
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
39#define PCH_SPSR_TFD 0x000007C0
40#define PCH_SPSR_RFD 0x0000F800
41
42#define PCH_READABLE(x) (((x) & PCH_SPSR_RFD)>>11)
43#define PCH_WRITABLE(x) (((x) & PCH_SPSR_TFD)>>6)
44
45#define PCH_RX_THOLD 7
46#define PCH_RX_THOLD_MAX 15
47
48#define PCH_MAX_BAUDRATE 5000000
49#define PCH_MAX_FIFO_DEPTH 16
50
51#define STATUS_RUNNING 1
52#define STATUS_EXITING 2
53#define PCH_SLEEP_TIME 10
54
55#define PCH_ADDRESS_SIZE 0x20
56
57#define SSN_LOW 0x02U
58#define SSN_NO_CONTROL 0x00U
59#define PCH_MAX_CS 0xFF
60#define PCI_DEVICE_ID_GE_SPI 0x8816
61
62#define SPCR_SPE_BIT (1 << 0)
63#define SPCR_MSTR_BIT (1 << 1)
64#define SPCR_LSBF_BIT (1 << 4)
65#define SPCR_CPHA_BIT (1 << 5)
66#define SPCR_CPOL_BIT (1 << 6)
67#define SPCR_TFIE_BIT (1 << 8)
68#define SPCR_RFIE_BIT (1 << 9)
69#define SPCR_FIE_BIT (1 << 10)
70#define SPCR_ORIE_BIT (1 << 11)
71#define SPCR_MDFIE_BIT (1 << 12)
72#define SPCR_FICLR_BIT (1 << 24)
73#define SPSR_TFI_BIT (1 << 0)
74#define SPSR_RFI_BIT (1 << 1)
75#define SPSR_FI_BIT (1 << 2)
76#define SPBRR_SIZE_BIT (1 << 10)
77
78#define PCH_ALL (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|SPCR_ORIE_BIT|SPCR_MDFIE_BIT)
79
80#define SPCR_RFIC_FIELD 20
81#define SPCR_TFIC_FIELD 16
82
83#define SPSR_INT_BITS 0x1F
84#define MASK_SPBRR_SPBR_BITS (~((1 << 10) - 1))
85#define MASK_RFIC_SPCR_BITS (~(0xf << 20))
86#define MASK_TFIC_SPCR_BITS (~(0xf000f << 12))
87
88#define PCH_CLOCK_HZ 50000000
89#define PCH_MAX_SPBR 1023
90
91
92/**
93 * struct pch_spi_data - Holds the SPI channel specific details
94 * @io_remap_addr: The remapped PCI base address
95 * @master: Pointer to the SPI master structure
96 * @work: Reference to work queue handler
97 * @wk: Workqueue for carrying out execution of the
98 * requests
99 * @wait: Wait queue for waking up upon receiving an
100 * interrupt.
101 * @transfer_complete: Status of SPI Transfer
102 * @bcurrent_msg_processing: Status flag for message processing
103 * @lock: Lock for protecting this structure
104 * @queue: SPI Message queue
105 * @status: Status of the SPI driver
106 * @bpw_len: Length of data to be transferred in bits per
107 * word
108 * @transfer_active: Flag showing active transfer
109 * @tx_index: Transmit data count; for bookkeeping during
110 * transfer
111 * @rx_index: Receive data count; for bookkeeping during
112 * transfer
113 * @tx_buff: Buffer for data to be transmitted
114 * @rx_index: Buffer for Received data
115 * @n_curnt_chip: The chip number that this SPI driver currently
116 * operates on
117 * @current_chip: Reference to the current chip that this SPI
118 * driver currently operates on
119 * @current_msg: The current message that this SPI driver is
120 * handling
121 * @cur_trans: The current transfer that this SPI driver is
122 * handling
123 * @board_dat: Reference to the SPI device data structure
124 */
125struct pch_spi_data {
126 void __iomem *io_remap_addr;
127 struct spi_master *master;
128 struct work_struct work;
129 struct workqueue_struct *wk;
130 wait_queue_head_t wait;
131 u8 transfer_complete;
132 u8 bcurrent_msg_processing;
133 spinlock_t lock;
134 struct list_head queue;
135 u8 status;
136 u32 bpw_len;
137 u8 transfer_active;
138 u32 tx_index;
139 u32 rx_index;
140 u16 *pkt_tx_buff;
141 u16 *pkt_rx_buff;
142 u8 n_curnt_chip;
143 struct spi_device *current_chip;
144 struct spi_message *current_msg;
145 struct spi_transfer *cur_trans;
146 struct pch_spi_board_data *board_dat;
147};
148
149/**
150 * struct pch_spi_board_data - Holds the SPI device specific details
151 * @pdev: Pointer to the PCI device
152 * @irq_reg_sts: Status of IRQ registration
153 * @pci_req_sts: Status of pci_request_regions
154 * @suspend_sts: Status of suspend
155 * @data: Pointer to SPI channel data structure
156 */
157struct pch_spi_board_data {
158 struct pci_dev *pdev;
159 u8 irq_reg_sts;
160 u8 pci_req_sts;
161 u8 suspend_sts;
162 struct pch_spi_data *data;
163};
164
165static struct pci_device_id pch_spi_pcidev_id[] = {
166 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_GE_SPI)},
167 {0,}
168};
169
170/**
171 * pch_spi_writereg() - Performs register writes
172 * @master: Pointer to struct spi_master.
173 * @idx: Register offset.
174 * @val: Value to be written to register.
175 */
176static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val)
177{
178 struct pch_spi_data *data = spi_master_get_devdata(master);
179 iowrite32(val, (data->io_remap_addr + idx));
180}
181
182/**
183 * pch_spi_readreg() - Performs register reads
184 * @master: Pointer to struct spi_master.
185 * @idx: Register offset.
186 */
187static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
188{
189 struct pch_spi_data *data = spi_master_get_devdata(master);
190 return ioread32(data->io_remap_addr + idx);
191}
192
193static inline void pch_spi_setclr_reg(struct spi_master *master, int idx,
194 u32 set, u32 clr)
195{
196 u32 tmp = pch_spi_readreg(master, idx);
197 tmp = (tmp & ~clr) | set;
198 pch_spi_writereg(master, idx, tmp);
199}
200
201static void pch_spi_set_master_mode(struct spi_master *master)
202{
203 pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0);
204}
205
206/**
207 * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
208 * @master: Pointer to struct spi_master.
209 */
210static void pch_spi_clear_fifo(struct spi_master *master)
211{
212 pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0);
213 pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT);
214}
215
216static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
217 void __iomem *io_remap_addr)
218{
219 u32 n_read, tx_index, rx_index, bpw_len;
220 u16 *pkt_rx_buffer, *pkt_tx_buff;
221 int read_cnt;
222 u32 reg_spcr_val;
223 void __iomem *spsr;
224 void __iomem *spdrr;
225 void __iomem *spdwr;
226
227 spsr = io_remap_addr + PCH_SPSR;
228 iowrite32(reg_spsr_val, spsr);
229
230 if (data->transfer_active) {
231 rx_index = data->rx_index;
232 tx_index = data->tx_index;
233 bpw_len = data->bpw_len;
234 pkt_rx_buffer = data->pkt_rx_buff;
235 pkt_tx_buff = data->pkt_tx_buff;
236
237 spdrr = io_remap_addr + PCH_SPDRR;
238 spdwr = io_remap_addr + PCH_SPDWR;
239
240 n_read = PCH_READABLE(reg_spsr_val);
241
242 for (read_cnt = 0; (read_cnt < n_read); read_cnt++) {
243 pkt_rx_buffer[rx_index++] = ioread32(spdrr);
244 if (tx_index < bpw_len)
245 iowrite32(pkt_tx_buff[tx_index++], spdwr);
246 }
247
248 /* disable RFI if not needed */
249 if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
250 reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
251 reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
252
253 /* reset rx threshold */
254 reg_spcr_val &= MASK_RFIC_SPCR_BITS;
255 reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
256 iowrite32(((reg_spcr_val) &= (~(SPCR_RFIE_BIT))),
257 (io_remap_addr + PCH_SPCR));
258 }
259
260 /* update counts */
261 data->tx_index = tx_index;
262 data->rx_index = rx_index;
263
264 }
265
266 /* if transfer complete interrupt */
267 if (reg_spsr_val & SPSR_FI_BIT) {
268 /* disable FI & RFI interrupts */
269 pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
270 SPCR_FIE_BIT | SPCR_RFIE_BIT);
271
272 /* transfer is completed;inform pch_spi_process_messages */
273 data->transfer_complete = true;
274 wake_up(&data->wait);
275 }
276}
277
278/**
279 * pch_spi_handler() - Interrupt handler
280 * @irq: The interrupt number.
281 * @dev_id: Pointer to struct pch_spi_board_data.
282 */
283static irqreturn_t pch_spi_handler(int irq, void *dev_id)
284{
285 u32 reg_spsr_val;
286 struct pch_spi_data *data;
287 void __iomem *spsr;
288 void __iomem *io_remap_addr;
289 irqreturn_t ret = IRQ_NONE;
290 struct pch_spi_board_data *board_dat = dev_id;
291
292 if (board_dat->suspend_sts) {
293 dev_dbg(&board_dat->pdev->dev,
294 "%s returning due to suspend\n", __func__);
295 return IRQ_NONE;
296 }
297
298 data = board_dat->data;
299 io_remap_addr = data->io_remap_addr;
300 spsr = io_remap_addr + PCH_SPSR;
301
302 reg_spsr_val = ioread32(spsr);
303
304 /* Check if the interrupt is for SPI device */
305 if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
306 pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
307 ret = IRQ_HANDLED;
308 }
309
310 dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
311 __func__, ret);
312
313 return ret;
314}
315
316/**
317 * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
318 * @master: Pointer to struct spi_master.
319 * @speed_hz: Baud rate.
320 */
321static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
322{
323 u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
324
325 /* if baud rate is less than we can support limit it */
326 if (n_spbr > PCH_MAX_SPBR)
327 n_spbr = PCH_MAX_SPBR;
328
329 pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, ~MASK_SPBRR_SPBR_BITS);
330}
331
332/**
333 * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
334 * @master: Pointer to struct spi_master.
335 * @bits_per_word: Bits per word for SPI transfer.
336 */
337static void pch_spi_set_bits_per_word(struct spi_master *master,
338 u8 bits_per_word)
339{
340 if (bits_per_word == 8)
341 pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
342 else
343 pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
344}
345
346/**
347 * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
348 * @spi: Pointer to struct spi_device.
349 */
350static void pch_spi_setup_transfer(struct spi_device *spi)
351{
352 u32 flags = 0;
353
354 dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
355 __func__, pch_spi_readreg(spi->master, PCH_SPBRR),
356 spi->max_speed_hz);
357 pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
358
359 /* set bits per word */
360 pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
361
362 if (!(spi->mode & SPI_LSB_FIRST))
363 flags |= SPCR_LSBF_BIT;
364 if (spi->mode & SPI_CPOL)
365 flags |= SPCR_CPOL_BIT;
366 if (spi->mode & SPI_CPHA)
367 flags |= SPCR_CPHA_BIT;
368 pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
369 (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
370
371 /* Clear the FIFO by toggling FICLR to 1 and back to 0 */
372 pch_spi_clear_fifo(spi->master);
373}
374
375/**
376 * pch_spi_reset() - Clears SPI registers
377 * @master: Pointer to struct spi_master.
378 */
379static void pch_spi_reset(struct spi_master *master)
380{
381 /* write 1 to reset SPI */
382 pch_spi_writereg(master, PCH_SRST, 0x1);
383
384 /* clear reset */
385 pch_spi_writereg(master, PCH_SRST, 0x0);
386}
387
388static int pch_spi_setup(struct spi_device *pspi)
389{
390 /* check bits per word */
391 if (pspi->bits_per_word == 0) {
392 pspi->bits_per_word = 8;
393 dev_dbg(&pspi->dev, "%s 8 bits per word\n", __func__);
394 }
395
396 if ((pspi->bits_per_word != 8) && (pspi->bits_per_word != 16)) {
397 dev_err(&pspi->dev, "%s Invalid bits per word\n", __func__);
398 return -EINVAL;
399 }
400
401 /* Check baud rate setting */
402 /* if baud rate of chip is greater than
403 max we can support,return error */
404 if ((pspi->max_speed_hz) > PCH_MAX_BAUDRATE)
405 pspi->max_speed_hz = PCH_MAX_BAUDRATE;
406
407 dev_dbg(&pspi->dev, "%s MODE = %x\n", __func__,
408 (pspi->mode) & (SPI_CPOL | SPI_CPHA));
409
410 return 0;
411}
412
413static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
414{
415
416 struct spi_transfer *transfer;
417 struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
418 int retval;
419 unsigned long flags;
420
421 /* validate spi message and baud rate */
422 if (unlikely(list_empty(&pmsg->transfers) == 1)) {
423 dev_err(&pspi->dev, "%s list empty\n", __func__);
424 retval = -EINVAL;
425 goto err_out;
426 }
427
428 if (unlikely(pspi->max_speed_hz == 0)) {
429 dev_err(&pspi->dev, "%s pch_spi_tranfer maxspeed=%d\n",
430 __func__, pspi->max_speed_hz);
431 retval = -EINVAL;
432 goto err_out;
433 }
434
435 dev_dbg(&pspi->dev, "%s Transfer List not empty. "
436 "Transfer Speed is set.\n", __func__);
437
438 /* validate Tx/Rx buffers and Transfer length */
439 list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
440 if (!transfer->tx_buf && !transfer->rx_buf) {
441 dev_err(&pspi->dev,
442 "%s Tx and Rx buffer NULL\n", __func__);
443 retval = -EINVAL;
444 goto err_out;
445 }
446
447 if (!transfer->len) {
448 dev_err(&pspi->dev, "%s Transfer length invalid\n",
449 __func__);
450 retval = -EINVAL;
451 goto err_out;
452 }
453
454 dev_dbg(&pspi->dev, "%s Tx/Rx buffer valid. Transfer length"
455 " valid\n", __func__);
456
457 /* if baud rate hs been specified validate the same */
458 if (transfer->speed_hz > PCH_MAX_BAUDRATE)
459 transfer->speed_hz = PCH_MAX_BAUDRATE;
460
461 /* if bits per word has been specified validate the same */
462 if (transfer->bits_per_word) {
463 if ((transfer->bits_per_word != 8)
464 && (transfer->bits_per_word != 16)) {
465 retval = -EINVAL;
466 dev_err(&pspi->dev,
467 "%s Invalid bits per word\n", __func__);
468 goto err_out;
469 }
470 }
471 }
472
473 spin_lock_irqsave(&data->lock, flags);
474
475 /* We won't process any messages if we have been asked to terminate */
476 if (data->status == STATUS_EXITING) {
477 dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
478 retval = -ESHUTDOWN;
479 goto err_return_spinlock;
480 }
481
482 /* If suspended ,return -EINVAL */
483 if (data->board_dat->suspend_sts) {
484 dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
485 retval = -EINVAL;
486 goto err_return_spinlock;
487 }
488
489 /* set status of message */
490 pmsg->actual_length = 0;
491 dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
492
493 pmsg->status = -EINPROGRESS;
494
495 /* add message to queue */
496 list_add_tail(&pmsg->queue, &data->queue);
497 dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
498
499 /* schedule work queue to run */
500 queue_work(data->wk, &data->work);
501 dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
502
503 retval = 0;
504
505err_return_spinlock:
506 spin_unlock_irqrestore(&data->lock, flags);
507err_out:
508 dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
509 return retval;
510}
511
512static inline void pch_spi_select_chip(struct pch_spi_data *data,
513 struct spi_device *pspi)
514{
515 if (data->current_chip != NULL) {
516 if (pspi->chip_select != data->n_curnt_chip) {
517 dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
518 data->current_chip = NULL;
519 }
520 }
521
522 data->current_chip = pspi;
523
524 data->n_curnt_chip = data->current_chip->chip_select;
525
526 dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
527 pch_spi_setup_transfer(pspi);
528}
529
530static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
531 struct spi_message **ppmsg)
532{
533 int size;
534 u32 n_writes;
535 int j;
536 struct spi_message *pmsg;
537 const u8 *tx_buf;
538 const u16 *tx_sbuf;
539
540 pmsg = *ppmsg;
541
542 /* set baud rate if needed */
543 if (data->cur_trans->speed_hz) {
544 dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
545 pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
546 }
547
548 /* set bits per word if needed */
549 if (data->cur_trans->bits_per_word &&
550 (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
551 dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
552 pch_spi_set_bits_per_word(data->master,
553 data->cur_trans->bits_per_word);
554 *bpw = data->cur_trans->bits_per_word;
555 } else {
556 *bpw = data->current_msg->spi->bits_per_word;
557 }
558
559 /* reset Tx/Rx index */
560 data->tx_index = 0;
561 data->rx_index = 0;
562
563 data->bpw_len = data->cur_trans->len / (*bpw / 8);
564
565 /* find alloc size */
566 size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
567
568 /* allocate memory for pkt_tx_buff & pkt_rx_buffer */
569 data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
570 if (data->pkt_tx_buff != NULL) {
571 data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
572 if (!data->pkt_rx_buff)
573 kfree(data->pkt_tx_buff);
574 }
575
576 if (!data->pkt_rx_buff) {
577 /* flush queue and set status of all transfers to -ENOMEM */
578 dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__);
579 list_for_each_entry(pmsg, data->queue.next, queue) {
580 pmsg->status = -ENOMEM;
581
582 if (pmsg->complete != 0)
583 pmsg->complete(pmsg->context);
584
585 /* delete from queue */
586 list_del_init(&pmsg->queue);
587 }
588 return;
589 }
590
591 /* copy Tx Data */
592 if (data->cur_trans->tx_buf != NULL) {
593 if (*bpw == 8) {
594 tx_buf = data->cur_trans->tx_buf;
595 for (j = 0; j < data->bpw_len; j++)
596 data->pkt_tx_buff[j] = *tx_buf++;
597 } else {
598 tx_sbuf = data->cur_trans->tx_buf;
599 for (j = 0; j < data->bpw_len; j++)
600 data->pkt_tx_buff[j] = *tx_sbuf++;
601 }
602 }
603
604 /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
605 n_writes = data->bpw_len;
606 if (n_writes > PCH_MAX_FIFO_DEPTH)
607 n_writes = PCH_MAX_FIFO_DEPTH;
608
609 dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
610 "0x2 to SSNXCR\n", __func__);
611 pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
612
613 for (j = 0; j < n_writes; j++)
614 pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
615
616 /* update tx_index */
617 data->tx_index = j;
618
619 /* reset transfer complete flag */
620 data->transfer_complete = false;
621 data->transfer_active = true;
622}
623
624
625static void pch_spi_nomore_transfer(struct pch_spi_data *data,
626 struct spi_message *pmsg)
627{
628 dev_dbg(&data->master->dev, "%s called\n", __func__);
629 /* Invoke complete callback
630 * [To the spi core..indicating end of transfer] */
631 data->current_msg->status = 0;
632
633 if (data->current_msg->complete != 0) {
634 dev_dbg(&data->master->dev,
635 "%s:Invoking callback of SPI core\n", __func__);
636 data->current_msg->complete(data->current_msg->context);
637 }
638
639 /* update status in global variable */
640 data->bcurrent_msg_processing = false;
641
642 dev_dbg(&data->master->dev,
643 "%s:data->bcurrent_msg_processing = false\n", __func__);
644
645 data->current_msg = NULL;
646 data->cur_trans = NULL;
647
648 /* check if we have items in list and not suspending
649 * return 1 if list empty */
650 if ((list_empty(&data->queue) == 0) &&
651 (!data->board_dat->suspend_sts) &&
652 (data->status != STATUS_EXITING)) {
653 /* We have some more work to do (either there is more tranint
654 * bpw;sfer requests in the current message or there are
655 *more messages)
656 */
657 dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
658 queue_work(data->wk, &data->work);
659 } else if (data->board_dat->suspend_sts ||
660 data->status == STATUS_EXITING) {
661 dev_dbg(&data->master->dev,
662 "%s suspend/remove initiated, flushing queue\n",
663 __func__);
664 list_for_each_entry(pmsg, data->queue.next, queue) {
665 pmsg->status = -EIO;
666
667 if (pmsg->complete)
668 pmsg->complete(pmsg->context);
669
670 /* delete from queue */
671 list_del_init(&pmsg->queue);
672 }
673 }
674}
675
676static void pch_spi_set_ir(struct pch_spi_data *data)
677{
678 /* enable interrupts */
679 if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) {
680 /* set receive threshold to PCH_RX_THOLD */
681 pch_spi_setclr_reg(data->master, PCH_SPCR,
682 PCH_RX_THOLD << SPCR_RFIC_FIELD,
683 ~MASK_RFIC_SPCR_BITS);
684 /* enable FI and RFI interrupts */
685 pch_spi_setclr_reg(data->master, PCH_SPCR,
686 SPCR_RFIE_BIT | SPCR_FIE_BIT, 0);
687 } else {
688 /* set receive threshold to maximum */
689 pch_spi_setclr_reg(data->master, PCH_SPCR,
690 PCH_RX_THOLD_MAX << SPCR_TFIC_FIELD,
691 ~MASK_TFIC_SPCR_BITS);
692 /* enable FI interrupt */
693 pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_FIE_BIT, 0);
694 }
695
696 dev_dbg(&data->master->dev,
697 "%s:invoking pch_spi_set_enable to enable SPI\n", __func__);
698
699 /* SPI set enable */
700 pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, SPCR_SPE_BIT, 0);
701
702 /* Wait until the transfer completes; go to sleep after
703 initiating the transfer. */
704 dev_dbg(&data->master->dev,
705 "%s:waiting for transfer to get over\n", __func__);
706
707 wait_event_interruptible(data->wait, data->transfer_complete);
708
709 pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
710 dev_dbg(&data->master->dev,
711 "%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
712
713 data->transfer_active = false;
714 dev_dbg(&data->master->dev,
715 "%s set data->transfer_active = false\n", __func__);
716
717 /* clear all interrupts */
718 pch_spi_writereg(data->master, PCH_SPSR,
719 pch_spi_readreg(data->master, PCH_SPSR));
720 /* disable interrupts */
721 pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
722}
723
724static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
725{
726 int j;
727 u8 *rx_buf;
728 u16 *rx_sbuf;
729
730 /* copy Rx Data */
731 if (!data->cur_trans->rx_buf)
732 return;
733
734 if (bpw == 8) {
735 rx_buf = data->cur_trans->rx_buf;
736 for (j = 0; j < data->bpw_len; j++)
737 *rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
738 } else {
739 rx_sbuf = data->cur_trans->rx_buf;
740 for (j = 0; j < data->bpw_len; j++)
741 *rx_sbuf++ = data->pkt_rx_buff[j];
742 }
743}
744
745
746static void pch_spi_process_messages(struct work_struct *pwork)
747{
748 struct spi_message *pmsg;
749 struct pch_spi_data *data;
750 int bpw;
751
752 data = container_of(pwork, struct pch_spi_data, work);
753 dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
754
755 spin_lock(&data->lock);
756
757 /* check if suspend has been initiated;if yes flush queue */
758 if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
759 dev_dbg(&data->master->dev,
760 "%s suspend/remove initiated,flushing queue\n",
761 __func__);
762
763 list_for_each_entry(pmsg, data->queue.next, queue) {
764 pmsg->status = -EIO;
765
766 if (pmsg->complete != 0) {
767 spin_unlock(&data->lock);
768 pmsg->complete(pmsg->context);
769 spin_lock(&data->lock);
770 }
771
772 /* delete from queue */
773 list_del_init(&pmsg->queue);
774 }
775
776 spin_unlock(&data->lock);
777 return;
778 }
779
780 data->bcurrent_msg_processing = true;
781 dev_dbg(&data->master->dev,
782 "%s Set data->bcurrent_msg_processing= true\n", __func__);
783
784 /* Get the message from the queue and delete it from there. */
785 data->current_msg = list_entry(data->queue.next, struct spi_message,
786 queue);
787
788 list_del_init(&data->current_msg->queue);
789
790 data->current_msg->status = 0;
791
792 pch_spi_select_chip(data, data->current_msg->spi);
793
794 spin_unlock(&data->lock);
795
796 do {
797 /* If we are already processing a message get the next
798 transfer structure from the message otherwise retrieve
799 the 1st transfer request from the message. */
800 spin_lock(&data->lock);
801
802 if (data->cur_trans == NULL) {
803 data->cur_trans =
804 list_entry(data->current_msg->transfers.
805 next, struct spi_transfer,
806 transfer_list);
807 dev_dbg(&data->master->dev,
808 "%s :Getting 1st transfer message\n", __func__);
809 } else {
810 data->cur_trans =
811 list_entry(data->cur_trans->transfer_list.next,
812 struct spi_transfer,
813 transfer_list);
814 dev_dbg(&data->master->dev,
815 "%s :Getting next transfer message\n",
816 __func__);
817 }
818
819 spin_unlock(&data->lock);
820
821 pch_spi_set_tx(data, &bpw, &pmsg);
822
823 /* Control interrupt*/
824 pch_spi_set_ir(data);
825
826 /* Disable SPI transfer */
827 pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, 0,
828 SPCR_SPE_BIT);
829
830 /* clear FIFO */
831 pch_spi_clear_fifo(data->master);
832
833 /* copy Rx Data */
834 pch_spi_copy_rx_data(data, bpw);
835
836 /* free memory */
837 kfree(data->pkt_rx_buff);
838 data->pkt_rx_buff = NULL;
839
840 kfree(data->pkt_tx_buff);
841 data->pkt_tx_buff = NULL;
842
843 /* increment message count */
844 data->current_msg->actual_length += data->cur_trans->len;
845
846 dev_dbg(&data->master->dev,
847 "%s:data->current_msg->actual_length=%d\n",
848 __func__, data->current_msg->actual_length);
849
850 /* check for delay */
851 if (data->cur_trans->delay_usecs) {
852 dev_dbg(&data->master->dev, "%s:"
853 "delay in usec=%d\n", __func__,
854 data->cur_trans->delay_usecs);
855 udelay(data->cur_trans->delay_usecs);
856 }
857
858 spin_lock(&data->lock);
859
860 /* No more transfer in this message. */
861 if ((data->cur_trans->transfer_list.next) ==
862 &(data->current_msg->transfers)) {
863 pch_spi_nomore_transfer(data, pmsg);
864 }
865
866 spin_unlock(&data->lock);
867
868 } while (data->cur_trans != NULL);
869}
870
871static void pch_spi_free_resources(struct pch_spi_board_data *board_dat)
872{
873 dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
874
875 /* free workqueue */
876 if (board_dat->data->wk != NULL) {
877 destroy_workqueue(board_dat->data->wk);
878 board_dat->data->wk = NULL;
879 dev_dbg(&board_dat->pdev->dev,
880 "%s destroy_workqueue invoked successfully\n",
881 __func__);
882 }
883
884 /* disable interrupts & free IRQ */
885 if (board_dat->irq_reg_sts) {
886 /* disable interrupts */
887 pch_spi_setclr_reg(board_dat->data->master, PCH_SPCR, 0,
888 PCH_ALL);
889
890 /* free IRQ */
891 free_irq(board_dat->pdev->irq, board_dat);
892
893 dev_dbg(&board_dat->pdev->dev,
894 "%s free_irq invoked successfully\n", __func__);
895
896 board_dat->irq_reg_sts = false;
897 }
898
899 /* unmap PCI base address */
900 if (board_dat->data->io_remap_addr != 0) {
901 pci_iounmap(board_dat->pdev, board_dat->data->io_remap_addr);
902
903 board_dat->data->io_remap_addr = 0;
904
905 dev_dbg(&board_dat->pdev->dev,
906 "%s pci_iounmap invoked successfully\n", __func__);
907 }
908
909 /* release PCI region */
910 if (board_dat->pci_req_sts) {
911 pci_release_regions(board_dat->pdev);
912 dev_dbg(&board_dat->pdev->dev,
913 "%s pci_release_regions invoked successfully\n",
914 __func__);
915 board_dat->pci_req_sts = false;
916 }
917}
918
919static int pch_spi_get_resources(struct pch_spi_board_data *board_dat)
920{
921 void __iomem *io_remap_addr;
922 int retval;
923 dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
924
925 /* create workqueue */
926 board_dat->data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
927 if (!board_dat->data->wk) {
928 dev_err(&board_dat->pdev->dev,
929 "%s create_singlet hread_workqueue failed\n", __func__);
930 retval = -EBUSY;
931 goto err_return;
932 }
933
934 dev_dbg(&board_dat->pdev->dev,
935 "%s create_singlethread_workqueue success\n", __func__);
936
937 retval = pci_request_regions(board_dat->pdev, KBUILD_MODNAME);
938 if (retval != 0) {
939 dev_err(&board_dat->pdev->dev,
940 "%s request_region failed\n", __func__);
941 goto err_return;
942 }
943
944 board_dat->pci_req_sts = true;
945
946 io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
947 if (io_remap_addr == 0) {
948 dev_err(&board_dat->pdev->dev,
949 "%s pci_iomap failed\n", __func__);
950 retval = -ENOMEM;
951 goto err_return;
952 }
953
954 /* calculate base address for all channels */
955 board_dat->data->io_remap_addr = io_remap_addr;
956
957 /* reset PCH SPI h/w */
958 pch_spi_reset(board_dat->data->master);
959 dev_dbg(&board_dat->pdev->dev,
960 "%s pch_spi_reset invoked successfully\n", __func__);
961
962 /* register IRQ */
963 retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
964 IRQF_SHARED, KBUILD_MODNAME, board_dat);
965 if (retval != 0) {
966 dev_err(&board_dat->pdev->dev,
967 "%s request_irq failed\n", __func__);
968 goto err_return;
969 }
970
971 dev_dbg(&board_dat->pdev->dev, "%s request_irq returned=%d\n",
972 __func__, retval);
973
974 board_dat->irq_reg_sts = true;
975 dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
976
977err_return:
978 if (retval != 0) {
979 dev_err(&board_dat->pdev->dev,
980 "%s FAIL:invoking pch_spi_free_resources\n", __func__);
981 pch_spi_free_resources(board_dat);
982 }
983
984 dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
985
986 return retval;
987}
988
989static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
990{
991
992 struct spi_master *master;
993
994 struct pch_spi_board_data *board_dat;
995 int retval;
996
997 dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
998
999 /* allocate memory for private data */
1000 board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
1001 if (board_dat == NULL) {
1002 dev_err(&pdev->dev,
1003 " %s memory allocation for private data failed\n",
1004 __func__);
1005 retval = -ENOMEM;
1006 goto err_kmalloc;
1007 }
1008
1009 dev_dbg(&pdev->dev,
1010 "%s memory allocation for private data success\n", __func__);
1011
1012 /* enable PCI device */
1013 retval = pci_enable_device(pdev);
1014 if (retval != 0) {
1015 dev_err(&pdev->dev, "%s pci_enable_device FAILED\n", __func__);
1016
1017 goto err_pci_en_device;
1018 }
1019
1020 dev_dbg(&pdev->dev, "%s pci_enable_device returned=%d\n",
1021 __func__, retval);
1022
1023 board_dat->pdev = pdev;
1024
1025 /* alllocate memory for SPI master */
1026 master = spi_alloc_master(&pdev->dev, sizeof(struct pch_spi_data));
1027 if (master == NULL) {
1028 retval = -ENOMEM;
1029 dev_err(&pdev->dev, "%s Fail.\n", __func__);
1030 goto err_spi_alloc_master;
1031 }
1032
1033 dev_dbg(&pdev->dev,
1034 "%s spi_alloc_master returned non NULL\n", __func__);
1035
1036 /* initialize members of SPI master */
1037 master->bus_num = -1;
1038 master->num_chipselect = PCH_MAX_CS;
1039 master->setup = pch_spi_setup;
1040 master->transfer = pch_spi_transfer;
1041 dev_dbg(&pdev->dev,
1042 "%s transfer member of SPI master initialized\n", __func__);
1043
1044 board_dat->data = spi_master_get_devdata(master);
1045
1046 board_dat->data->master = master;
1047 board_dat->data->n_curnt_chip = 255;
1048 board_dat->data->board_dat = board_dat;
1049 board_dat->data->status = STATUS_RUNNING;
1050
1051 INIT_LIST_HEAD(&board_dat->data->queue);
1052 spin_lock_init(&board_dat->data->lock);
1053 INIT_WORK(&board_dat->data->work, pch_spi_process_messages);
1054 init_waitqueue_head(&board_dat->data->wait);
1055
1056 /* allocate resources for PCH SPI */
1057 retval = pch_spi_get_resources(board_dat);
1058 if (retval) {
1059 dev_err(&pdev->dev, "%s fail(retval=%d)\n", __func__, retval);
1060 goto err_spi_get_resources;
1061 }
1062
1063 dev_dbg(&pdev->dev, "%s pch_spi_get_resources returned=%d\n",
1064 __func__, retval);
1065
1066 /* save private data in dev */
1067 pci_set_drvdata(pdev, board_dat);
1068 dev_dbg(&pdev->dev, "%s invoked pci_set_drvdata\n", __func__);
1069
1070 /* set master mode */
1071 pch_spi_set_master_mode(master);
1072 dev_dbg(&pdev->dev,
1073 "%s invoked pch_spi_set_master_mode\n", __func__);
1074
1075 /* Register the controller with the SPI core. */
1076 retval = spi_register_master(master);
1077 if (retval != 0) {
1078 dev_err(&pdev->dev,
1079 "%s spi_register_master FAILED\n", __func__);
1080 goto err_spi_reg_master;
1081 }
1082
1083 dev_dbg(&pdev->dev, "%s spi_register_master returned=%d\n",
1084 __func__, retval);
1085
1086
1087 return 0;
1088
1089err_spi_reg_master:
1090 spi_unregister_master(master);
1091err_spi_get_resources:
1092err_spi_alloc_master:
1093 spi_master_put(master);
1094 pci_disable_device(pdev);
1095err_pci_en_device:
1096 kfree(board_dat);
1097err_kmalloc:
1098 return retval;
1099}
1100
1101static void pch_spi_remove(struct pci_dev *pdev)
1102{
1103 struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
1104 int count;
1105
1106 dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1107
1108 if (!board_dat) {
1109 dev_err(&pdev->dev,
1110 "%s pci_get_drvdata returned NULL\n", __func__);
1111 return;
1112 }
1113
1114 /* check for any pending messages; no action is taken if the queue
1115 * is still full; but at least we tried. Unload anyway */
1116 count = 500;
1117 spin_lock(&board_dat->data->lock);
1118 board_dat->data->status = STATUS_EXITING;
1119 while ((list_empty(&board_dat->data->queue) == 0) && --count) {
1120 dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
1121 __func__);
1122 spin_unlock(&board_dat->data->lock);
1123 msleep(PCH_SLEEP_TIME);
1124 spin_lock(&board_dat->data->lock);
1125 }
1126 spin_unlock(&board_dat->data->lock);
1127
1128 /* Free resources allocated for PCH SPI */
1129 pch_spi_free_resources(board_dat);
1130
1131 spi_unregister_master(board_dat->data->master);
1132
1133 /* free memory for private data */
1134 kfree(board_dat);
1135
1136 pci_set_drvdata(pdev, NULL);
1137
1138 /* disable PCI device */
1139 pci_disable_device(pdev);
1140
1141 dev_dbg(&pdev->dev, "%s invoked pci_disable_device\n", __func__);
1142}
1143
1144#ifdef CONFIG_PM
1145static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
1146{
1147 u8 count;
1148 int retval;
1149
1150 struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
1151
1152 dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1153
1154 if (!board_dat) {
1155 dev_err(&pdev->dev,
1156 "%s pci_get_drvdata returned NULL\n", __func__);
1157 return -EFAULT;
1158 }
1159
1160 retval = 0;
1161 board_dat->suspend_sts = true;
1162
1163 /* check if the current message is processed:
1164 Only after thats done the transfer will be suspended */
1165 count = 255;
1166 while ((--count) > 0) {
1167 if (!(board_dat->data->bcurrent_msg_processing)) {
1168 dev_dbg(&pdev->dev, "%s board_dat->data->bCurrent_"
1169 "msg_processing = false\n", __func__);
1170 break;
1171 } else {
1172 dev_dbg(&pdev->dev, "%s board_dat->data->bCurrent_msg_"
1173 "processing = true\n", __func__);
1174 }
1175 msleep(PCH_SLEEP_TIME);
1176 }
1177
1178 /* Free IRQ */
1179 if (board_dat->irq_reg_sts) {
1180 /* disable all interrupts */
1181 pch_spi_setclr_reg(board_dat->data->master, PCH_SPCR, 0,
1182 PCH_ALL);
1183 pch_spi_reset(board_dat->data->master);
1184
1185 free_irq(board_dat->pdev->irq, board_dat);
1186
1187 board_dat->irq_reg_sts = false;
1188 dev_dbg(&pdev->dev,
1189 "%s free_irq invoked successfully.\n", __func__);
1190 }
1191
1192 /* save config space */
1193 retval = pci_save_state(pdev);
1194
1195 if (retval == 0) {
1196 dev_dbg(&pdev->dev, "%s pci_save_state returned=%d\n",
1197 __func__, retval);
1198 /* disable PM notifications */
1199 pci_enable_wake(pdev, PCI_D3hot, 0);
1200 dev_dbg(&pdev->dev,
1201 "%s pci_enable_wake invoked successfully\n", __func__);
1202 /* disable PCI device */
1203 pci_disable_device(pdev);
1204 dev_dbg(&pdev->dev,
1205 "%s pci_disable_device invoked successfully\n",
1206 __func__);
1207 /* move device to D3hot state */
1208 pci_set_power_state(pdev, PCI_D3hot);
1209 dev_dbg(&pdev->dev,
1210 "%s pci_set_power_state invoked successfully\n",
1211 __func__);
1212 } else {
1213 dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
1214 }
1215
1216 dev_dbg(&pdev->dev, "%s return=%d\n", __func__, retval);
1217
1218 return retval;
1219}
1220
1221static int pch_spi_resume(struct pci_dev *pdev)
1222{
1223 int retval;
1224
1225 struct pch_spi_board_data *board = pci_get_drvdata(pdev);
1226 dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
1227
1228 if (!board) {
1229 dev_err(&pdev->dev,
1230 "%s pci_get_drvdata returned NULL\n", __func__);
1231 return -EFAULT;
1232 }
1233
1234 /* move device to DO power state */
1235 pci_set_power_state(pdev, PCI_D0);
1236
1237 /* restore state */
1238 pci_restore_state(pdev);
1239
1240 retval = pci_enable_device(pdev);
1241 if (retval < 0) {
1242 dev_err(&pdev->dev,
1243 "%s pci_enable_device failed\n", __func__);
1244 } else {
1245 /* disable PM notifications */
1246 pci_enable_wake(pdev, PCI_D3hot, 0);
1247
1248 /* register IRQ handler */
1249 if (!board->irq_reg_sts) {
1250 /* register IRQ */
1251 retval = request_irq(board->pdev->irq, pch_spi_handler,
1252 IRQF_SHARED, KBUILD_MODNAME,
1253 board);
1254 if (retval < 0) {
1255 dev_err(&pdev->dev,
1256 "%s request_irq failed\n", __func__);
1257 return retval;
1258 }
1259 board->irq_reg_sts = true;
1260
1261 /* reset PCH SPI h/w */
1262 pch_spi_reset(board->data->master);
1263 pch_spi_set_master_mode(board->data->master);
1264
1265 /* set suspend status to false */
1266 board->suspend_sts = false;
1267
1268 }
1269 }
1270
1271 dev_dbg(&pdev->dev, "%s returning=%d\n", __func__, retval);
1272
1273 return retval;
1274}
1275#else
1276#define pch_spi_suspend NULL
1277#define pch_spi_resume NULL
1278
1279#endif
1280
1281static struct pci_driver pch_spi_pcidev = {
1282 .name = "pch_spi",
1283 .id_table = pch_spi_pcidev_id,
1284 .probe = pch_spi_probe,
1285 .remove = pch_spi_remove,
1286 .suspend = pch_spi_suspend,
1287 .resume = pch_spi_resume,
1288};
1289
1290static int __init pch_spi_init(void)
1291{
1292 return pci_register_driver(&pch_spi_pcidev);
1293}
1294module_init(pch_spi_init);
1295
1296static void __exit pch_spi_exit(void)
1297{
1298 pci_unregister_driver(&pch_spi_pcidev);
1299}
1300module_exit(pch_spi_exit);
1301
1302MODULE_LICENSE("GPL");
1303MODULE_DESCRIPTION("Topcliff PCH SPI PCI Driver");
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-28 17:16:08 -0500