x86/build: Don't add -maccumulate-outgoing-args w/o compiler support
[linux/fpc-iii.git] / drivers / spi / spi-bcm63xx.c
blobfee747030ee67e4cf2e81ab0a8e6329e861675eb
1 /*
2 * Broadcom BCM63xx SPI controller support
4 * Copyright (C) 2009-2012 Florian Fainelli <florian@openwrt.org>
5 * Copyright (C) 2010 Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
18 #include <linux/kernel.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <linux/spi/spi.h>
26 #include <linux/completion.h>
27 #include <linux/err.h>
28 #include <linux/pm_runtime.h>
30 /* BCM 6338/6348 SPI core */
31 #define SPI_6348_RSET_SIZE 64
32 #define SPI_6348_CMD 0x00 /* 16-bits register */
33 #define SPI_6348_INT_STATUS 0x02
34 #define SPI_6348_INT_MASK_ST 0x03
35 #define SPI_6348_INT_MASK 0x04
36 #define SPI_6348_ST 0x05
37 #define SPI_6348_CLK_CFG 0x06
38 #define SPI_6348_FILL_BYTE 0x07
39 #define SPI_6348_MSG_TAIL 0x09
40 #define SPI_6348_RX_TAIL 0x0b
41 #define SPI_6348_MSG_CTL 0x40 /* 8-bits register */
42 #define SPI_6348_MSG_CTL_WIDTH 8
43 #define SPI_6348_MSG_DATA 0x41
44 #define SPI_6348_MSG_DATA_SIZE 0x3f
45 #define SPI_6348_RX_DATA 0x80
46 #define SPI_6348_RX_DATA_SIZE 0x3f
48 /* BCM 3368/6358/6262/6368 SPI core */
49 #define SPI_6358_RSET_SIZE 1804
50 #define SPI_6358_MSG_CTL 0x00 /* 16-bits register */
51 #define SPI_6358_MSG_CTL_WIDTH 16
52 #define SPI_6358_MSG_DATA 0x02
53 #define SPI_6358_MSG_DATA_SIZE 0x21e
54 #define SPI_6358_RX_DATA 0x400
55 #define SPI_6358_RX_DATA_SIZE 0x220
56 #define SPI_6358_CMD 0x700 /* 16-bits register */
57 #define SPI_6358_INT_STATUS 0x702
58 #define SPI_6358_INT_MASK_ST 0x703
59 #define SPI_6358_INT_MASK 0x704
60 #define SPI_6358_ST 0x705
61 #define SPI_6358_CLK_CFG 0x706
62 #define SPI_6358_FILL_BYTE 0x707
63 #define SPI_6358_MSG_TAIL 0x709
64 #define SPI_6358_RX_TAIL 0x70B
66 /* Shared SPI definitions */
68 /* Message configuration */
69 #define SPI_FD_RW 0x00
70 #define SPI_HD_W 0x01
71 #define SPI_HD_R 0x02
72 #define SPI_BYTE_CNT_SHIFT 0
73 #define SPI_6348_MSG_TYPE_SHIFT 6
74 #define SPI_6358_MSG_TYPE_SHIFT 14
76 /* Command */
77 #define SPI_CMD_NOOP 0x00
78 #define SPI_CMD_SOFT_RESET 0x01
79 #define SPI_CMD_HARD_RESET 0x02
80 #define SPI_CMD_START_IMMEDIATE 0x03
81 #define SPI_CMD_COMMAND_SHIFT 0
82 #define SPI_CMD_COMMAND_MASK 0x000f
83 #define SPI_CMD_DEVICE_ID_SHIFT 4
84 #define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
85 #define SPI_CMD_ONE_BYTE_SHIFT 11
86 #define SPI_CMD_ONE_WIRE_SHIFT 12
87 #define SPI_DEV_ID_0 0
88 #define SPI_DEV_ID_1 1
89 #define SPI_DEV_ID_2 2
90 #define SPI_DEV_ID_3 3
92 /* Interrupt mask */
93 #define SPI_INTR_CMD_DONE 0x01
94 #define SPI_INTR_RX_OVERFLOW 0x02
95 #define SPI_INTR_TX_UNDERFLOW 0x04
96 #define SPI_INTR_TX_OVERFLOW 0x08
97 #define SPI_INTR_RX_UNDERFLOW 0x10
98 #define SPI_INTR_CLEAR_ALL 0x1f
100 /* Status */
101 #define SPI_RX_EMPTY 0x02
102 #define SPI_CMD_BUSY 0x04
103 #define SPI_SERIAL_BUSY 0x08
105 /* Clock configuration */
106 #define SPI_CLK_20MHZ 0x00
107 #define SPI_CLK_0_391MHZ 0x01
108 #define SPI_CLK_0_781MHZ 0x02 /* default */
109 #define SPI_CLK_1_563MHZ 0x03
110 #define SPI_CLK_3_125MHZ 0x04
111 #define SPI_CLK_6_250MHZ 0x05
112 #define SPI_CLK_12_50MHZ 0x06
113 #define SPI_CLK_MASK 0x07
114 #define SPI_SSOFFTIME_MASK 0x38
115 #define SPI_SSOFFTIME_SHIFT 3
116 #define SPI_BYTE_SWAP 0x80
118 enum bcm63xx_regs_spi {
119 SPI_CMD,
120 SPI_INT_STATUS,
121 SPI_INT_MASK_ST,
122 SPI_INT_MASK,
123 SPI_ST,
124 SPI_CLK_CFG,
125 SPI_FILL_BYTE,
126 SPI_MSG_TAIL,
127 SPI_RX_TAIL,
128 SPI_MSG_CTL,
129 SPI_MSG_DATA,
130 SPI_RX_DATA,
131 SPI_MSG_TYPE_SHIFT,
132 SPI_MSG_CTL_WIDTH,
133 SPI_MSG_DATA_SIZE,
136 #define BCM63XX_SPI_MAX_PREPEND 15
138 #define BCM63XX_SPI_MAX_CS 8
139 #define BCM63XX_SPI_BUS_NUM 0
141 struct bcm63xx_spi {
142 struct completion done;
144 void __iomem *regs;
145 int irq;
147 /* Platform data */
148 const unsigned long *reg_offsets;
149 unsigned fifo_size;
150 unsigned int msg_type_shift;
151 unsigned int msg_ctl_width;
153 /* data iomem */
154 u8 __iomem *tx_io;
155 const u8 __iomem *rx_io;
157 struct clk *clk;
158 struct platform_device *pdev;
161 static inline u8 bcm_spi_readb(struct bcm63xx_spi *bs,
162 unsigned int offset)
164 return readb(bs->regs + bs->reg_offsets[offset]);
167 static inline u16 bcm_spi_readw(struct bcm63xx_spi *bs,
168 unsigned int offset)
170 #ifdef CONFIG_CPU_BIG_ENDIAN
171 return ioread16be(bs->regs + bs->reg_offsets[offset]);
172 #else
173 return readw(bs->regs + bs->reg_offsets[offset]);
174 #endif
177 static inline void bcm_spi_writeb(struct bcm63xx_spi *bs,
178 u8 value, unsigned int offset)
180 writeb(value, bs->regs + bs->reg_offsets[offset]);
183 static inline void bcm_spi_writew(struct bcm63xx_spi *bs,
184 u16 value, unsigned int offset)
186 #ifdef CONFIG_CPU_BIG_ENDIAN
187 iowrite16be(value, bs->regs + bs->reg_offsets[offset]);
188 #else
189 writew(value, bs->regs + bs->reg_offsets[offset]);
190 #endif
193 static const unsigned bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = {
194 { 20000000, SPI_CLK_20MHZ },
195 { 12500000, SPI_CLK_12_50MHZ },
196 { 6250000, SPI_CLK_6_250MHZ },
197 { 3125000, SPI_CLK_3_125MHZ },
198 { 1563000, SPI_CLK_1_563MHZ },
199 { 781000, SPI_CLK_0_781MHZ },
200 { 391000, SPI_CLK_0_391MHZ }
203 static void bcm63xx_spi_setup_transfer(struct spi_device *spi,
204 struct spi_transfer *t)
206 struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
207 u8 clk_cfg, reg;
208 int i;
210 /* Default to lowest clock configuration */
211 clk_cfg = SPI_CLK_0_391MHZ;
213 /* Find the closest clock configuration */
214 for (i = 0; i < SPI_CLK_MASK; i++) {
215 if (t->speed_hz >= bcm63xx_spi_freq_table[i][0]) {
216 clk_cfg = bcm63xx_spi_freq_table[i][1];
217 break;
221 /* clear existing clock configuration bits of the register */
222 reg = bcm_spi_readb(bs, SPI_CLK_CFG);
223 reg &= ~SPI_CLK_MASK;
224 reg |= clk_cfg;
226 bcm_spi_writeb(bs, reg, SPI_CLK_CFG);
227 dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n",
228 clk_cfg, t->speed_hz);
231 /* the spi->mode bits understood by this driver: */
232 #define MODEBITS (SPI_CPOL | SPI_CPHA)
234 static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *first,
235 unsigned int num_transfers)
237 struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
238 u16 msg_ctl;
239 u16 cmd;
240 unsigned int i, timeout = 0, prepend_len = 0, len = 0;
241 struct spi_transfer *t = first;
242 bool do_rx = false;
243 bool do_tx = false;
245 /* Disable the CMD_DONE interrupt */
246 bcm_spi_writeb(bs, 0, SPI_INT_MASK);
248 dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n",
249 t->tx_buf, t->rx_buf, t->len);
251 if (num_transfers > 1 && t->tx_buf && t->len <= BCM63XX_SPI_MAX_PREPEND)
252 prepend_len = t->len;
254 /* prepare the buffer */
255 for (i = 0; i < num_transfers; i++) {
256 if (t->tx_buf) {
257 do_tx = true;
258 memcpy_toio(bs->tx_io + len, t->tx_buf, t->len);
260 /* don't prepend more than one tx */
261 if (t != first)
262 prepend_len = 0;
265 if (t->rx_buf) {
266 do_rx = true;
267 /* prepend is half-duplex write only */
268 if (t == first)
269 prepend_len = 0;
272 len += t->len;
274 t = list_entry(t->transfer_list.next, struct spi_transfer,
275 transfer_list);
278 reinit_completion(&bs->done);
280 /* Fill in the Message control register */
281 msg_ctl = (len << SPI_BYTE_CNT_SHIFT);
283 if (do_rx && do_tx && prepend_len == 0)
284 msg_ctl |= (SPI_FD_RW << bs->msg_type_shift);
285 else if (do_rx)
286 msg_ctl |= (SPI_HD_R << bs->msg_type_shift);
287 else if (do_tx)
288 msg_ctl |= (SPI_HD_W << bs->msg_type_shift);
290 switch (bs->msg_ctl_width) {
291 case 8:
292 bcm_spi_writeb(bs, msg_ctl, SPI_MSG_CTL);
293 break;
294 case 16:
295 bcm_spi_writew(bs, msg_ctl, SPI_MSG_CTL);
296 break;
299 /* Issue the transfer */
300 cmd = SPI_CMD_START_IMMEDIATE;
301 cmd |= (prepend_len << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
302 cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT);
303 bcm_spi_writew(bs, cmd, SPI_CMD);
305 /* Enable the CMD_DONE interrupt */
306 bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
308 timeout = wait_for_completion_timeout(&bs->done, HZ);
309 if (!timeout)
310 return -ETIMEDOUT;
312 if (!do_rx)
313 return 0;
315 len = 0;
316 t = first;
317 /* Read out all the data */
318 for (i = 0; i < num_transfers; i++) {
319 if (t->rx_buf)
320 memcpy_fromio(t->rx_buf, bs->rx_io + len, t->len);
322 if (t != first || prepend_len == 0)
323 len += t->len;
325 t = list_entry(t->transfer_list.next, struct spi_transfer,
326 transfer_list);
329 return 0;
332 static int bcm63xx_spi_transfer_one(struct spi_master *master,
333 struct spi_message *m)
335 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
336 struct spi_transfer *t, *first = NULL;
337 struct spi_device *spi = m->spi;
338 int status = 0;
339 unsigned int n_transfers = 0, total_len = 0;
340 bool can_use_prepend = false;
343 * This SPI controller does not support keeping CS active after a
344 * transfer.
345 * Work around this by merging as many transfers we can into one big
346 * full-duplex transfers.
348 list_for_each_entry(t, &m->transfers, transfer_list) {
349 if (!first)
350 first = t;
352 n_transfers++;
353 total_len += t->len;
355 if (n_transfers == 2 && !first->rx_buf && !t->tx_buf &&
356 first->len <= BCM63XX_SPI_MAX_PREPEND)
357 can_use_prepend = true;
358 else if (can_use_prepend && t->tx_buf)
359 can_use_prepend = false;
361 /* we can only transfer one fifo worth of data */
362 if ((can_use_prepend &&
363 total_len > (bs->fifo_size + BCM63XX_SPI_MAX_PREPEND)) ||
364 (!can_use_prepend && total_len > bs->fifo_size)) {
365 dev_err(&spi->dev, "unable to do transfers larger than FIFO size (%i > %i)\n",
366 total_len, bs->fifo_size);
367 status = -EINVAL;
368 goto exit;
371 /* all combined transfers have to have the same speed */
372 if (t->speed_hz != first->speed_hz) {
373 dev_err(&spi->dev, "unable to change speed between transfers\n");
374 status = -EINVAL;
375 goto exit;
378 /* CS will be deasserted directly after transfer */
379 if (t->delay_usecs) {
380 dev_err(&spi->dev, "unable to keep CS asserted after transfer\n");
381 status = -EINVAL;
382 goto exit;
385 if (t->cs_change ||
386 list_is_last(&t->transfer_list, &m->transfers)) {
387 /* configure adapter for a new transfer */
388 bcm63xx_spi_setup_transfer(spi, first);
390 /* send the data */
391 status = bcm63xx_txrx_bufs(spi, first, n_transfers);
392 if (status)
393 goto exit;
395 m->actual_length += total_len;
397 first = NULL;
398 n_transfers = 0;
399 total_len = 0;
400 can_use_prepend = false;
403 exit:
404 m->status = status;
405 spi_finalize_current_message(master);
407 return 0;
410 /* This driver supports single master mode only. Hence
411 * CMD_DONE is the only interrupt we care about
413 static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id)
415 struct spi_master *master = (struct spi_master *)dev_id;
416 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
417 u8 intr;
419 /* Read interupts and clear them immediately */
420 intr = bcm_spi_readb(bs, SPI_INT_STATUS);
421 bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
422 bcm_spi_writeb(bs, 0, SPI_INT_MASK);
424 /* A transfer completed */
425 if (intr & SPI_INTR_CMD_DONE)
426 complete(&bs->done);
428 return IRQ_HANDLED;
431 static const unsigned long bcm6348_spi_reg_offsets[] = {
432 [SPI_CMD] = SPI_6348_CMD,
433 [SPI_INT_STATUS] = SPI_6348_INT_STATUS,
434 [SPI_INT_MASK_ST] = SPI_6348_INT_MASK_ST,
435 [SPI_INT_MASK] = SPI_6348_INT_MASK,
436 [SPI_ST] = SPI_6348_ST,
437 [SPI_CLK_CFG] = SPI_6348_CLK_CFG,
438 [SPI_FILL_BYTE] = SPI_6348_FILL_BYTE,
439 [SPI_MSG_TAIL] = SPI_6348_MSG_TAIL,
440 [SPI_RX_TAIL] = SPI_6348_RX_TAIL,
441 [SPI_MSG_CTL] = SPI_6348_MSG_CTL,
442 [SPI_MSG_DATA] = SPI_6348_MSG_DATA,
443 [SPI_RX_DATA] = SPI_6348_RX_DATA,
444 [SPI_MSG_TYPE_SHIFT] = SPI_6348_MSG_TYPE_SHIFT,
445 [SPI_MSG_CTL_WIDTH] = SPI_6348_MSG_CTL_WIDTH,
446 [SPI_MSG_DATA_SIZE] = SPI_6348_MSG_DATA_SIZE,
449 static const unsigned long bcm6358_spi_reg_offsets[] = {
450 [SPI_CMD] = SPI_6358_CMD,
451 [SPI_INT_STATUS] = SPI_6358_INT_STATUS,
452 [SPI_INT_MASK_ST] = SPI_6358_INT_MASK_ST,
453 [SPI_INT_MASK] = SPI_6358_INT_MASK,
454 [SPI_ST] = SPI_6358_ST,
455 [SPI_CLK_CFG] = SPI_6358_CLK_CFG,
456 [SPI_FILL_BYTE] = SPI_6358_FILL_BYTE,
457 [SPI_MSG_TAIL] = SPI_6358_MSG_TAIL,
458 [SPI_RX_TAIL] = SPI_6358_RX_TAIL,
459 [SPI_MSG_CTL] = SPI_6358_MSG_CTL,
460 [SPI_MSG_DATA] = SPI_6358_MSG_DATA,
461 [SPI_RX_DATA] = SPI_6358_RX_DATA,
462 [SPI_MSG_TYPE_SHIFT] = SPI_6358_MSG_TYPE_SHIFT,
463 [SPI_MSG_CTL_WIDTH] = SPI_6358_MSG_CTL_WIDTH,
464 [SPI_MSG_DATA_SIZE] = SPI_6358_MSG_DATA_SIZE,
467 static const struct platform_device_id bcm63xx_spi_dev_match[] = {
469 .name = "bcm6348-spi",
470 .driver_data = (unsigned long)bcm6348_spi_reg_offsets,
473 .name = "bcm6358-spi",
474 .driver_data = (unsigned long)bcm6358_spi_reg_offsets,
480 static int bcm63xx_spi_probe(struct platform_device *pdev)
482 struct resource *r;
483 const unsigned long *bcm63xx_spireg;
484 struct device *dev = &pdev->dev;
485 int irq;
486 struct spi_master *master;
487 struct clk *clk;
488 struct bcm63xx_spi *bs;
489 int ret;
491 if (!pdev->id_entry->driver_data)
492 return -EINVAL;
494 bcm63xx_spireg = (const unsigned long *)pdev->id_entry->driver_data;
496 irq = platform_get_irq(pdev, 0);
497 if (irq < 0) {
498 dev_err(dev, "no irq\n");
499 return -ENXIO;
502 clk = devm_clk_get(dev, "spi");
503 if (IS_ERR(clk)) {
504 dev_err(dev, "no clock for device\n");
505 return PTR_ERR(clk);
508 master = spi_alloc_master(dev, sizeof(*bs));
509 if (!master) {
510 dev_err(dev, "out of memory\n");
511 return -ENOMEM;
514 bs = spi_master_get_devdata(master);
515 init_completion(&bs->done);
517 platform_set_drvdata(pdev, master);
518 bs->pdev = pdev;
520 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
521 bs->regs = devm_ioremap_resource(&pdev->dev, r);
522 if (IS_ERR(bs->regs)) {
523 ret = PTR_ERR(bs->regs);
524 goto out_err;
527 bs->irq = irq;
528 bs->clk = clk;
529 bs->reg_offsets = bcm63xx_spireg;
530 bs->fifo_size = bs->reg_offsets[SPI_MSG_DATA_SIZE];
532 ret = devm_request_irq(&pdev->dev, irq, bcm63xx_spi_interrupt, 0,
533 pdev->name, master);
534 if (ret) {
535 dev_err(dev, "unable to request irq\n");
536 goto out_err;
539 master->bus_num = BCM63XX_SPI_BUS_NUM;
540 master->num_chipselect = BCM63XX_SPI_MAX_CS;
541 master->transfer_one_message = bcm63xx_spi_transfer_one;
542 master->mode_bits = MODEBITS;
543 master->bits_per_word_mask = SPI_BPW_MASK(8);
544 master->auto_runtime_pm = true;
545 bs->msg_type_shift = bs->reg_offsets[SPI_MSG_TYPE_SHIFT];
546 bs->msg_ctl_width = bs->reg_offsets[SPI_MSG_CTL_WIDTH];
547 bs->tx_io = (u8 *)(bs->regs + bs->reg_offsets[SPI_MSG_DATA]);
548 bs->rx_io = (const u8 *)(bs->regs + bs->reg_offsets[SPI_RX_DATA]);
550 /* Initialize hardware */
551 ret = clk_prepare_enable(bs->clk);
552 if (ret)
553 goto out_err;
555 bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
557 /* register and we are done */
558 ret = devm_spi_register_master(dev, master);
559 if (ret) {
560 dev_err(dev, "spi register failed\n");
561 goto out_clk_disable;
564 dev_info(dev, "at %pr (irq %d, FIFOs size %d)\n",
565 r, irq, bs->fifo_size);
567 return 0;
569 out_clk_disable:
570 clk_disable_unprepare(clk);
571 out_err:
572 spi_master_put(master);
573 return ret;
576 static int bcm63xx_spi_remove(struct platform_device *pdev)
578 struct spi_master *master = platform_get_drvdata(pdev);
579 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
581 /* reset spi block */
582 bcm_spi_writeb(bs, 0, SPI_INT_MASK);
584 /* HW shutdown */
585 clk_disable_unprepare(bs->clk);
587 return 0;
590 #ifdef CONFIG_PM_SLEEP
591 static int bcm63xx_spi_suspend(struct device *dev)
593 struct spi_master *master = dev_get_drvdata(dev);
594 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
596 spi_master_suspend(master);
598 clk_disable_unprepare(bs->clk);
600 return 0;
603 static int bcm63xx_spi_resume(struct device *dev)
605 struct spi_master *master = dev_get_drvdata(dev);
606 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
607 int ret;
609 ret = clk_prepare_enable(bs->clk);
610 if (ret)
611 return ret;
613 spi_master_resume(master);
615 return 0;
617 #endif
619 static const struct dev_pm_ops bcm63xx_spi_pm_ops = {
620 SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend, bcm63xx_spi_resume)
623 static struct platform_driver bcm63xx_spi_driver = {
624 .driver = {
625 .name = "bcm63xx-spi",
626 .pm = &bcm63xx_spi_pm_ops,
628 .id_table = bcm63xx_spi_dev_match,
629 .probe = bcm63xx_spi_probe,
630 .remove = bcm63xx_spi_remove,
633 module_platform_driver(bcm63xx_spi_driver);
635 MODULE_ALIAS("platform:bcm63xx_spi");
636 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
637 MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
638 MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
639 MODULE_LICENSE("GPL");