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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>
29#include <linux/of.h>
30
31
32#define SPI_6348_RSET_SIZE 64
33#define SPI_6348_CMD 0x00
34#define SPI_6348_INT_STATUS 0x02
35#define SPI_6348_INT_MASK_ST 0x03
36#define SPI_6348_INT_MASK 0x04
37#define SPI_6348_ST 0x05
38#define SPI_6348_CLK_CFG 0x06
39#define SPI_6348_FILL_BYTE 0x07
40#define SPI_6348_MSG_TAIL 0x09
41#define SPI_6348_RX_TAIL 0x0b
42#define SPI_6348_MSG_CTL 0x40
43#define SPI_6348_MSG_CTL_WIDTH 8
44#define SPI_6348_MSG_DATA 0x41
45#define SPI_6348_MSG_DATA_SIZE 0x3f
46#define SPI_6348_RX_DATA 0x80
47#define SPI_6348_RX_DATA_SIZE 0x3f
48
49
50#define SPI_6358_RSET_SIZE 1804
51#define SPI_6358_MSG_CTL 0x00
52#define SPI_6358_MSG_CTL_WIDTH 16
53#define SPI_6358_MSG_DATA 0x02
54#define SPI_6358_MSG_DATA_SIZE 0x21e
55#define SPI_6358_RX_DATA 0x400
56#define SPI_6358_RX_DATA_SIZE 0x220
57#define SPI_6358_CMD 0x700
58#define SPI_6358_INT_STATUS 0x702
59#define SPI_6358_INT_MASK_ST 0x703
60#define SPI_6358_INT_MASK 0x704
61#define SPI_6358_ST 0x705
62#define SPI_6358_CLK_CFG 0x706
63#define SPI_6358_FILL_BYTE 0x707
64#define SPI_6358_MSG_TAIL 0x709
65#define SPI_6358_RX_TAIL 0x70B
66
67
68
69
70#define SPI_FD_RW 0x00
71#define SPI_HD_W 0x01
72#define SPI_HD_R 0x02
73#define SPI_BYTE_CNT_SHIFT 0
74#define SPI_6348_MSG_TYPE_SHIFT 6
75#define SPI_6358_MSG_TYPE_SHIFT 14
76
77
78#define SPI_CMD_NOOP 0x00
79#define SPI_CMD_SOFT_RESET 0x01
80#define SPI_CMD_HARD_RESET 0x02
81#define SPI_CMD_START_IMMEDIATE 0x03
82#define SPI_CMD_COMMAND_SHIFT 0
83#define SPI_CMD_COMMAND_MASK 0x000f
84#define SPI_CMD_DEVICE_ID_SHIFT 4
85#define SPI_CMD_PREPEND_BYTE_CNT_SHIFT 8
86#define SPI_CMD_ONE_BYTE_SHIFT 11
87#define SPI_CMD_ONE_WIRE_SHIFT 12
88#define SPI_DEV_ID_0 0
89#define SPI_DEV_ID_1 1
90#define SPI_DEV_ID_2 2
91#define SPI_DEV_ID_3 3
92
93
94#define SPI_INTR_CMD_DONE 0x01
95#define SPI_INTR_RX_OVERFLOW 0x02
96#define SPI_INTR_TX_UNDERFLOW 0x04
97#define SPI_INTR_TX_OVERFLOW 0x08
98#define SPI_INTR_RX_UNDERFLOW 0x10
99#define SPI_INTR_CLEAR_ALL 0x1f
100
101
102#define SPI_RX_EMPTY 0x02
103#define SPI_CMD_BUSY 0x04
104#define SPI_SERIAL_BUSY 0x08
105
106
107#define SPI_CLK_20MHZ 0x00
108#define SPI_CLK_0_391MHZ 0x01
109#define SPI_CLK_0_781MHZ 0x02
110#define SPI_CLK_1_563MHZ 0x03
111#define SPI_CLK_3_125MHZ 0x04
112#define SPI_CLK_6_250MHZ 0x05
113#define SPI_CLK_12_50MHZ 0x06
114#define SPI_CLK_MASK 0x07
115#define SPI_SSOFFTIME_MASK 0x38
116#define SPI_SSOFFTIME_SHIFT 3
117#define SPI_BYTE_SWAP 0x80
118
119enum bcm63xx_regs_spi {
120 SPI_CMD,
121 SPI_INT_STATUS,
122 SPI_INT_MASK_ST,
123 SPI_INT_MASK,
124 SPI_ST,
125 SPI_CLK_CFG,
126 SPI_FILL_BYTE,
127 SPI_MSG_TAIL,
128 SPI_RX_TAIL,
129 SPI_MSG_CTL,
130 SPI_MSG_DATA,
131 SPI_RX_DATA,
132 SPI_MSG_TYPE_SHIFT,
133 SPI_MSG_CTL_WIDTH,
134 SPI_MSG_DATA_SIZE,
135};
136
137#define BCM63XX_SPI_MAX_PREPEND 15
138
139#define BCM63XX_SPI_MAX_CS 8
140#define BCM63XX_SPI_BUS_NUM 0
141
142struct bcm63xx_spi {
143 struct completion done;
144
145 void __iomem *regs;
146 int irq;
147
148
149 const unsigned long *reg_offsets;
150 unsigned int fifo_size;
151 unsigned int msg_type_shift;
152 unsigned int msg_ctl_width;
153
154
155 u8 __iomem *tx_io;
156 const u8 __iomem *rx_io;
157
158 struct clk *clk;
159 struct platform_device *pdev;
160};
161
162static inline u8 bcm_spi_readb(struct bcm63xx_spi *bs,
163 unsigned int offset)
164{
165 return readb(bs->regs + bs->reg_offsets[offset]);
166}
167
168static inline u16 bcm_spi_readw(struct bcm63xx_spi *bs,
169 unsigned int offset)
170{
171#ifdef CONFIG_CPU_BIG_ENDIAN
172 return ioread16be(bs->regs + bs->reg_offsets[offset]);
173#else
174 return readw(bs->regs + bs->reg_offsets[offset]);
175#endif
176}
177
178static inline void bcm_spi_writeb(struct bcm63xx_spi *bs,
179 u8 value, unsigned int offset)
180{
181 writeb(value, bs->regs + bs->reg_offsets[offset]);
182}
183
184static inline void bcm_spi_writew(struct bcm63xx_spi *bs,
185 u16 value, unsigned int offset)
186{
187#ifdef CONFIG_CPU_BIG_ENDIAN
188 iowrite16be(value, bs->regs + bs->reg_offsets[offset]);
189#else
190 writew(value, bs->regs + bs->reg_offsets[offset]);
191#endif
192}
193
194static const unsigned int bcm63xx_spi_freq_table[SPI_CLK_MASK][2] = {
195 { 20000000, SPI_CLK_20MHZ },
196 { 12500000, SPI_CLK_12_50MHZ },
197 { 6250000, SPI_CLK_6_250MHZ },
198 { 3125000, SPI_CLK_3_125MHZ },
199 { 1563000, SPI_CLK_1_563MHZ },
200 { 781000, SPI_CLK_0_781MHZ },
201 { 391000, SPI_CLK_0_391MHZ }
202};
203
204static void bcm63xx_spi_setup_transfer(struct spi_device *spi,
205 struct spi_transfer *t)
206{
207 struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
208 u8 clk_cfg, reg;
209 int i;
210
211
212 clk_cfg = SPI_CLK_0_391MHZ;
213
214
215 for (i = 0; i < SPI_CLK_MASK; i++) {
216 if (t->speed_hz >= bcm63xx_spi_freq_table[i][0]) {
217 clk_cfg = bcm63xx_spi_freq_table[i][1];
218 break;
219 }
220 }
221
222
223 reg = bcm_spi_readb(bs, SPI_CLK_CFG);
224 reg &= ~SPI_CLK_MASK;
225 reg |= clk_cfg;
226
227 bcm_spi_writeb(bs, reg, SPI_CLK_CFG);
228 dev_dbg(&spi->dev, "Setting clock register to %02x (hz %d)\n",
229 clk_cfg, t->speed_hz);
230}
231
232
233#define MODEBITS (SPI_CPOL | SPI_CPHA)
234
235static int bcm63xx_txrx_bufs(struct spi_device *spi, struct spi_transfer *first,
236 unsigned int num_transfers)
237{
238 struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
239 u16 msg_ctl;
240 u16 cmd;
241 unsigned int i, timeout = 0, prepend_len = 0, len = 0;
242 struct spi_transfer *t = first;
243 bool do_rx = false;
244 bool do_tx = false;
245
246
247 bcm_spi_writeb(bs, 0, SPI_INT_MASK);
248
249 dev_dbg(&spi->dev, "txrx: tx %p, rx %p, len %d\n",
250 t->tx_buf, t->rx_buf, t->len);
251
252 if (num_transfers > 1 && t->tx_buf && t->len <= BCM63XX_SPI_MAX_PREPEND)
253 prepend_len = t->len;
254
255
256 for (i = 0; i < num_transfers; i++) {
257 if (t->tx_buf) {
258 do_tx = true;
259 memcpy_toio(bs->tx_io + len, t->tx_buf, t->len);
260
261
262 if (t != first)
263 prepend_len = 0;
264 }
265
266 if (t->rx_buf) {
267 do_rx = true;
268
269 if (t == first)
270 prepend_len = 0;
271 }
272
273 len += t->len;
274
275 t = list_entry(t->transfer_list.next, struct spi_transfer,
276 transfer_list);
277 }
278
279 reinit_completion(&bs->done);
280
281
282 msg_ctl = (len << SPI_BYTE_CNT_SHIFT);
283
284 if (do_rx && do_tx && prepend_len == 0)
285 msg_ctl |= (SPI_FD_RW << bs->msg_type_shift);
286 else if (do_rx)
287 msg_ctl |= (SPI_HD_R << bs->msg_type_shift);
288 else if (do_tx)
289 msg_ctl |= (SPI_HD_W << bs->msg_type_shift);
290
291 switch (bs->msg_ctl_width) {
292 case 8:
293 bcm_spi_writeb(bs, msg_ctl, SPI_MSG_CTL);
294 break;
295 case 16:
296 bcm_spi_writew(bs, msg_ctl, SPI_MSG_CTL);
297 break;
298 }
299
300
301 cmd = SPI_CMD_START_IMMEDIATE;
302 cmd |= (prepend_len << SPI_CMD_PREPEND_BYTE_CNT_SHIFT);
303 cmd |= (spi->chip_select << SPI_CMD_DEVICE_ID_SHIFT);
304 bcm_spi_writew(bs, cmd, SPI_CMD);
305
306
307 bcm_spi_writeb(bs, SPI_INTR_CMD_DONE, SPI_INT_MASK);
308
309 timeout = wait_for_completion_timeout(&bs->done, HZ);
310 if (!timeout)
311 return -ETIMEDOUT;
312
313 if (!do_rx)
314 return 0;
315
316 len = 0;
317 t = first;
318
319 for (i = 0; i < num_transfers; i++) {
320 if (t->rx_buf)
321 memcpy_fromio(t->rx_buf, bs->rx_io + len, t->len);
322
323 if (t != first || prepend_len == 0)
324 len += t->len;
325
326 t = list_entry(t->transfer_list.next, struct spi_transfer,
327 transfer_list);
328 }
329
330 return 0;
331}
332
333static int bcm63xx_spi_transfer_one(struct spi_master *master,
334 struct spi_message *m)
335{
336 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
337 struct spi_transfer *t, *first = NULL;
338 struct spi_device *spi = m->spi;
339 int status = 0;
340 unsigned int n_transfers = 0, total_len = 0;
341 bool can_use_prepend = false;
342
343
344
345
346
347
348
349 list_for_each_entry(t, &m->transfers, transfer_list) {
350 if (!first)
351 first = t;
352
353 n_transfers++;
354 total_len += t->len;
355
356 if (n_transfers == 2 && !first->rx_buf && !t->tx_buf &&
357 first->len <= BCM63XX_SPI_MAX_PREPEND)
358 can_use_prepend = true;
359 else if (can_use_prepend && t->tx_buf)
360 can_use_prepend = false;
361
362
363 if ((can_use_prepend &&
364 total_len > (bs->fifo_size + BCM63XX_SPI_MAX_PREPEND)) ||
365 (!can_use_prepend && total_len > bs->fifo_size)) {
366 dev_err(&spi->dev, "unable to do transfers larger than FIFO size (%i > %i)\n",
367 total_len, bs->fifo_size);
368 status = -EINVAL;
369 goto exit;
370 }
371
372
373 if (t->speed_hz != first->speed_hz) {
374 dev_err(&spi->dev, "unable to change speed between transfers\n");
375 status = -EINVAL;
376 goto exit;
377 }
378
379
380 if (t->delay_usecs) {
381 dev_err(&spi->dev, "unable to keep CS asserted after transfer\n");
382 status = -EINVAL;
383 goto exit;
384 }
385
386 if (t->cs_change ||
387 list_is_last(&t->transfer_list, &m->transfers)) {
388
389 bcm63xx_spi_setup_transfer(spi, first);
390
391
392 status = bcm63xx_txrx_bufs(spi, first, n_transfers);
393 if (status)
394 goto exit;
395
396 m->actual_length += total_len;
397
398 first = NULL;
399 n_transfers = 0;
400 total_len = 0;
401 can_use_prepend = false;
402 }
403 }
404exit:
405 m->status = status;
406 spi_finalize_current_message(master);
407
408 return 0;
409}
410
411
412
413
414static irqreturn_t bcm63xx_spi_interrupt(int irq, void *dev_id)
415{
416 struct spi_master *master = (struct spi_master *)dev_id;
417 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
418 u8 intr;
419
420
421 intr = bcm_spi_readb(bs, SPI_INT_STATUS);
422 bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
423 bcm_spi_writeb(bs, 0, SPI_INT_MASK);
424
425
426 if (intr & SPI_INTR_CMD_DONE)
427 complete(&bs->done);
428
429 return IRQ_HANDLED;
430}
431
432static size_t bcm63xx_spi_max_length(struct spi_device *spi)
433{
434 struct bcm63xx_spi *bs = spi_master_get_devdata(spi->master);
435
436 return bs->fifo_size;
437}
438
439static const unsigned long bcm6348_spi_reg_offsets[] = {
440 [SPI_CMD] = SPI_6348_CMD,
441 [SPI_INT_STATUS] = SPI_6348_INT_STATUS,
442 [SPI_INT_MASK_ST] = SPI_6348_INT_MASK_ST,
443 [SPI_INT_MASK] = SPI_6348_INT_MASK,
444 [SPI_ST] = SPI_6348_ST,
445 [SPI_CLK_CFG] = SPI_6348_CLK_CFG,
446 [SPI_FILL_BYTE] = SPI_6348_FILL_BYTE,
447 [SPI_MSG_TAIL] = SPI_6348_MSG_TAIL,
448 [SPI_RX_TAIL] = SPI_6348_RX_TAIL,
449 [SPI_MSG_CTL] = SPI_6348_MSG_CTL,
450 [SPI_MSG_DATA] = SPI_6348_MSG_DATA,
451 [SPI_RX_DATA] = SPI_6348_RX_DATA,
452 [SPI_MSG_TYPE_SHIFT] = SPI_6348_MSG_TYPE_SHIFT,
453 [SPI_MSG_CTL_WIDTH] = SPI_6348_MSG_CTL_WIDTH,
454 [SPI_MSG_DATA_SIZE] = SPI_6348_MSG_DATA_SIZE,
455};
456
457static const unsigned long bcm6358_spi_reg_offsets[] = {
458 [SPI_CMD] = SPI_6358_CMD,
459 [SPI_INT_STATUS] = SPI_6358_INT_STATUS,
460 [SPI_INT_MASK_ST] = SPI_6358_INT_MASK_ST,
461 [SPI_INT_MASK] = SPI_6358_INT_MASK,
462 [SPI_ST] = SPI_6358_ST,
463 [SPI_CLK_CFG] = SPI_6358_CLK_CFG,
464 [SPI_FILL_BYTE] = SPI_6358_FILL_BYTE,
465 [SPI_MSG_TAIL] = SPI_6358_MSG_TAIL,
466 [SPI_RX_TAIL] = SPI_6358_RX_TAIL,
467 [SPI_MSG_CTL] = SPI_6358_MSG_CTL,
468 [SPI_MSG_DATA] = SPI_6358_MSG_DATA,
469 [SPI_RX_DATA] = SPI_6358_RX_DATA,
470 [SPI_MSG_TYPE_SHIFT] = SPI_6358_MSG_TYPE_SHIFT,
471 [SPI_MSG_CTL_WIDTH] = SPI_6358_MSG_CTL_WIDTH,
472 [SPI_MSG_DATA_SIZE] = SPI_6358_MSG_DATA_SIZE,
473};
474
475static const struct platform_device_id bcm63xx_spi_dev_match[] = {
476 {
477 .name = "bcm6348-spi",
478 .driver_data = (unsigned long)bcm6348_spi_reg_offsets,
479 },
480 {
481 .name = "bcm6358-spi",
482 .driver_data = (unsigned long)bcm6358_spi_reg_offsets,
483 },
484 {
485 },
486};
487
488static const struct of_device_id bcm63xx_spi_of_match[] = {
489 { .compatible = "brcm,bcm6348-spi", .data = &bcm6348_spi_reg_offsets },
490 { .compatible = "brcm,bcm6358-spi", .data = &bcm6358_spi_reg_offsets },
491 { },
492};
493
494static int bcm63xx_spi_probe(struct platform_device *pdev)
495{
496 struct resource *r;
497 const unsigned long *bcm63xx_spireg;
498 struct device *dev = &pdev->dev;
499 int irq, bus_num;
500 struct spi_master *master;
501 struct clk *clk;
502 struct bcm63xx_spi *bs;
503 int ret;
504 u32 num_cs = BCM63XX_SPI_MAX_CS;
505
506 if (dev->of_node) {
507 const struct of_device_id *match;
508
509 match = of_match_node(bcm63xx_spi_of_match, dev->of_node);
510 if (!match)
511 return -EINVAL;
512 bcm63xx_spireg = match->data;
513
514 of_property_read_u32(dev->of_node, "num-cs", &num_cs);
515 if (num_cs > BCM63XX_SPI_MAX_CS) {
516 dev_warn(dev, "unsupported number of cs (%i), reducing to 8\n",
517 num_cs);
518 num_cs = BCM63XX_SPI_MAX_CS;
519 }
520
521 bus_num = -1;
522 } else if (pdev->id_entry->driver_data) {
523 const struct platform_device_id *match = pdev->id_entry;
524
525 bcm63xx_spireg = (const unsigned long *)match->driver_data;
526 bus_num = BCM63XX_SPI_BUS_NUM;
527 } else {
528 return -EINVAL;
529 }
530
531 irq = platform_get_irq(pdev, 0);
532 if (irq < 0) {
533 dev_err(dev, "no irq\n");
534 return -ENXIO;
535 }
536
537 clk = devm_clk_get(dev, "spi");
538 if (IS_ERR(clk)) {
539 dev_err(dev, "no clock for device\n");
540 return PTR_ERR(clk);
541 }
542
543 master = spi_alloc_master(dev, sizeof(*bs));
544 if (!master) {
545 dev_err(dev, "out of memory\n");
546 return -ENOMEM;
547 }
548
549 bs = spi_master_get_devdata(master);
550 init_completion(&bs->done);
551
552 platform_set_drvdata(pdev, master);
553 bs->pdev = pdev;
554
555 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
556 bs->regs = devm_ioremap_resource(&pdev->dev, r);
557 if (IS_ERR(bs->regs)) {
558 ret = PTR_ERR(bs->regs);
559 goto out_err;
560 }
561
562 bs->irq = irq;
563 bs->clk = clk;
564 bs->reg_offsets = bcm63xx_spireg;
565 bs->fifo_size = bs->reg_offsets[SPI_MSG_DATA_SIZE];
566
567 ret = devm_request_irq(&pdev->dev, irq, bcm63xx_spi_interrupt, 0,
568 pdev->name, master);
569 if (ret) {
570 dev_err(dev, "unable to request irq\n");
571 goto out_err;
572 }
573
574 master->dev.of_node = dev->of_node;
575 master->bus_num = bus_num;
576 master->num_chipselect = num_cs;
577 master->transfer_one_message = bcm63xx_spi_transfer_one;
578 master->mode_bits = MODEBITS;
579 master->bits_per_word_mask = SPI_BPW_MASK(8);
580 master->max_transfer_size = bcm63xx_spi_max_length;
581 master->max_message_size = bcm63xx_spi_max_length;
582 master->auto_runtime_pm = true;
583 bs->msg_type_shift = bs->reg_offsets[SPI_MSG_TYPE_SHIFT];
584 bs->msg_ctl_width = bs->reg_offsets[SPI_MSG_CTL_WIDTH];
585 bs->tx_io = (u8 *)(bs->regs + bs->reg_offsets[SPI_MSG_DATA]);
586 bs->rx_io = (const u8 *)(bs->regs + bs->reg_offsets[SPI_RX_DATA]);
587
588
589 ret = clk_prepare_enable(bs->clk);
590 if (ret)
591 goto out_err;
592
593 bcm_spi_writeb(bs, SPI_INTR_CLEAR_ALL, SPI_INT_STATUS);
594
595
596 ret = devm_spi_register_master(dev, master);
597 if (ret) {
598 dev_err(dev, "spi register failed\n");
599 goto out_clk_disable;
600 }
601
602 dev_info(dev, "at %pr (irq %d, FIFOs size %d)\n",
603 r, irq, bs->fifo_size);
604
605 return 0;
606
607out_clk_disable:
608 clk_disable_unprepare(clk);
609out_err:
610 spi_master_put(master);
611 return ret;
612}
613
614static int bcm63xx_spi_remove(struct platform_device *pdev)
615{
616 struct spi_master *master = platform_get_drvdata(pdev);
617 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
618
619
620 bcm_spi_writeb(bs, 0, SPI_INT_MASK);
621
622
623 clk_disable_unprepare(bs->clk);
624
625 return 0;
626}
627
628#ifdef CONFIG_PM_SLEEP
629static int bcm63xx_spi_suspend(struct device *dev)
630{
631 struct spi_master *master = dev_get_drvdata(dev);
632 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
633
634 spi_master_suspend(master);
635
636 clk_disable_unprepare(bs->clk);
637
638 return 0;
639}
640
641static int bcm63xx_spi_resume(struct device *dev)
642{
643 struct spi_master *master = dev_get_drvdata(dev);
644 struct bcm63xx_spi *bs = spi_master_get_devdata(master);
645 int ret;
646
647 ret = clk_prepare_enable(bs->clk);
648 if (ret)
649 return ret;
650
651 spi_master_resume(master);
652
653 return 0;
654}
655#endif
656
657static const struct dev_pm_ops bcm63xx_spi_pm_ops = {
658 SET_SYSTEM_SLEEP_PM_OPS(bcm63xx_spi_suspend, bcm63xx_spi_resume)
659};
660
661static struct platform_driver bcm63xx_spi_driver = {
662 .driver = {
663 .name = "bcm63xx-spi",
664 .pm = &bcm63xx_spi_pm_ops,
665 .of_match_table = bcm63xx_spi_of_match,
666 },
667 .id_table = bcm63xx_spi_dev_match,
668 .probe = bcm63xx_spi_probe,
669 .remove = bcm63xx_spi_remove,
670};
671
672module_platform_driver(bcm63xx_spi_driver);
673
674MODULE_ALIAS("platform:bcm63xx_spi");
675MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
676MODULE_AUTHOR("Tanguy Bouzeloc <tanguy.bouzeloc@efixo.com>");
677MODULE_DESCRIPTION("Broadcom BCM63xx SPI Controller driver");
678MODULE_LICENSE("GPL");
679
