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1/*
2 * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
3 * Author: Addy Ke <addy.ke@rock-chips.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 */
15
16#include <linux/clk.h>
17#include <linux/dmaengine.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/platform_device.h>
21#include <linux/spi/spi.h>
22#include <linux/pm_runtime.h>
23#include <linux/scatterlist.h>
24
25#define DRIVER_NAME "rockchip-spi"
26
27/* SPI register offsets */
28#define ROCKCHIP_SPI_CTRLR0 0x0000
29#define ROCKCHIP_SPI_CTRLR1 0x0004
30#define ROCKCHIP_SPI_SSIENR 0x0008
31#define ROCKCHIP_SPI_SER 0x000c
32#define ROCKCHIP_SPI_BAUDR 0x0010
33#define ROCKCHIP_SPI_TXFTLR 0x0014
34#define ROCKCHIP_SPI_RXFTLR 0x0018
35#define ROCKCHIP_SPI_TXFLR 0x001c
36#define ROCKCHIP_SPI_RXFLR 0x0020
37#define ROCKCHIP_SPI_SR 0x0024
38#define ROCKCHIP_SPI_IPR 0x0028
39#define ROCKCHIP_SPI_IMR 0x002c
40#define ROCKCHIP_SPI_ISR 0x0030
41#define ROCKCHIP_SPI_RISR 0x0034
42#define ROCKCHIP_SPI_ICR 0x0038
43#define ROCKCHIP_SPI_DMACR 0x003c
44#define ROCKCHIP_SPI_DMATDLR 0x0040
45#define ROCKCHIP_SPI_DMARDLR 0x0044
46#define ROCKCHIP_SPI_TXDR 0x0400
47#define ROCKCHIP_SPI_RXDR 0x0800
48
49/* Bit fields in CTRLR0 */
50#define CR0_DFS_OFFSET 0
51
52#define CR0_CFS_OFFSET 2
53
54#define CR0_SCPH_OFFSET 6
55
56#define CR0_SCPOL_OFFSET 7
57
58#define CR0_CSM_OFFSET 8
59#define CR0_CSM_KEEP 0x0
60/* ss_n be high for half sclk_out cycles */
61#define CR0_CSM_HALF 0X1
62/* ss_n be high for one sclk_out cycle */
63#define CR0_CSM_ONE 0x2
64
65/* ss_n to sclk_out delay */
66#define CR0_SSD_OFFSET 10
67/*
68 * The period between ss_n active and
69 * sclk_out active is half sclk_out cycles
70 */
71#define CR0_SSD_HALF 0x0
72/*
73 * The period between ss_n active and
74 * sclk_out active is one sclk_out cycle
75 */
76#define CR0_SSD_ONE 0x1
77
78#define CR0_EM_OFFSET 11
79#define CR0_EM_LITTLE 0x0
80#define CR0_EM_BIG 0x1
81
82#define CR0_FBM_OFFSET 12
83#define CR0_FBM_MSB 0x0
84#define CR0_FBM_LSB 0x1
85
86#define CR0_BHT_OFFSET 13
87#define CR0_BHT_16BIT 0x0
88#define CR0_BHT_8BIT 0x1
89
90#define CR0_RSD_OFFSET 14
91
92#define CR0_FRF_OFFSET 16
93#define CR0_FRF_SPI 0x0
94#define CR0_FRF_SSP 0x1
95#define CR0_FRF_MICROWIRE 0x2
96
97#define CR0_XFM_OFFSET 18
98#define CR0_XFM_MASK (0x03 << SPI_XFM_OFFSET)
99#define CR0_XFM_TR 0x0
100#define CR0_XFM_TO 0x1
101#define CR0_XFM_RO 0x2
102
103#define CR0_OPM_OFFSET 20
104#define CR0_OPM_MASTER 0x0
105#define CR0_OPM_SLAVE 0x1
106
107#define CR0_MTM_OFFSET 0x21
108
109/* Bit fields in SER, 2bit */
110#define SER_MASK 0x3
111
112/* Bit fields in SR, 5bit */
113#define SR_MASK 0x1f
114#define SR_BUSY (1 << 0)
115#define SR_TF_FULL (1 << 1)
116#define SR_TF_EMPTY (1 << 2)
117#define SR_RF_EMPTY (1 << 3)
118#define SR_RF_FULL (1 << 4)
119
120/* Bit fields in ISR, IMR, ISR, RISR, 5bit */
121#define INT_MASK 0x1f
122#define INT_TF_EMPTY (1 << 0)
123#define INT_TF_OVERFLOW (1 << 1)
124#define INT_RF_UNDERFLOW (1 << 2)
125#define INT_RF_OVERFLOW (1 << 3)
126#define INT_RF_FULL (1 << 4)
127
128/* Bit fields in ICR, 4bit */
129#define ICR_MASK 0x0f
130#define ICR_ALL (1 << 0)
131#define ICR_RF_UNDERFLOW (1 << 1)
132#define ICR_RF_OVERFLOW (1 << 2)
133#define ICR_TF_OVERFLOW (1 << 3)
134
135/* Bit fields in DMACR */
136#define RF_DMA_EN (1 << 0)
137#define TF_DMA_EN (1 << 1)
138
139#define RXBUSY (1 << 0)
140#define TXBUSY (1 << 1)
141
142/* sclk_out: spi master internal logic in rk3x can support 50Mhz */
143#define MAX_SCLK_OUT 50000000
144
145enum rockchip_ssi_type {
146 SSI_MOTO_SPI = 0,
147 SSI_TI_SSP,
148 SSI_NS_MICROWIRE,
149};
150
151struct rockchip_spi_dma_data {
152 struct dma_chan *ch;
153 enum dma_transfer_direction direction;
154 dma_addr_t addr;
155};
156
157struct rockchip_spi {
158 struct device *dev;
159 struct spi_master *master;
160
161 struct clk *spiclk;
162 struct clk *apb_pclk;
163
164 void __iomem *regs;
165 /*depth of the FIFO buffer */
166 u32 fifo_len;
167 /* max bus freq supported */
168 u32 max_freq;
169 /* supported slave numbers */
170 enum rockchip_ssi_type type;
171
172 u16 mode;
173 u8 tmode;
174 u8 bpw;
175 u8 n_bytes;
176 u32 rsd_nsecs;
177 unsigned len;
178 u32 speed;
179
180 const void *tx;
181 const void *tx_end;
182 void *rx;
183 void *rx_end;
184
185 u32 state;
186 /* protect state */
187 spinlock_t lock;
188
189 u32 use_dma;
190 struct sg_table tx_sg;
191 struct sg_table rx_sg;
192 struct rockchip_spi_dma_data dma_rx;
193 struct rockchip_spi_dma_data dma_tx;
194 struct dma_slave_caps dma_caps;
195};
196
197static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
198{
199 writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
200}
201
202static inline void spi_set_clk(struct rockchip_spi *rs, u16 div)
203{
204 writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR);
205}
206
207static inline void flush_fifo(struct rockchip_spi *rs)
208{
209 while (readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR))
210 readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
211}
212
213static inline void wait_for_idle(struct rockchip_spi *rs)
214{
215 unsigned long timeout = jiffies + msecs_to_jiffies(5);
216
217 do {
218 if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))
219 return;
220 } while (!time_after(jiffies, timeout));
221
222 dev_warn(rs->dev, "spi controller is in busy state!\n");
223}
224
225static u32 get_fifo_len(struct rockchip_spi *rs)
226{
227 u32 fifo;
228
229 for (fifo = 2; fifo < 32; fifo++) {
230 writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR);
231 if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR))
232 break;
233 }
234
235 writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR);
236
237 return (fifo == 31) ? 0 : fifo;
238}
239
240static inline u32 tx_max(struct rockchip_spi *rs)
241{
242 u32 tx_left, tx_room;
243
244 tx_left = (rs->tx_end - rs->tx) / rs->n_bytes;
245 tx_room = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR);
246
247 return min(tx_left, tx_room);
248}
249
250static inline u32 rx_max(struct rockchip_spi *rs)
251{
252 u32 rx_left = (rs->rx_end - rs->rx) / rs->n_bytes;
253 u32 rx_room = (u32)readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
254
255 return min(rx_left, rx_room);
256}
257
258static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
259{
260 u32 ser;
261 struct spi_master *master = spi->master;
262 struct rockchip_spi *rs = spi_master_get_devdata(master);
263
264 pm_runtime_get_sync(rs->dev);
265
266 ser = readl_relaxed(rs->regs + ROCKCHIP_SPI_SER) & SER_MASK;
267
268 /*
269 * drivers/spi/spi.c:
270 * static void spi_set_cs(struct spi_device *spi, bool enable)
271 * {
272 * if (spi->mode & SPI_CS_HIGH)
273 * enable = !enable;
274 *
275 * if (spi->cs_gpio >= 0)
276 * gpio_set_value(spi->cs_gpio, !enable);
277 * else if (spi->master->set_cs)
278 * spi->master->set_cs(spi, !enable);
279 * }
280 *
281 * Note: enable(rockchip_spi_set_cs) = !enable(spi_set_cs)
282 */
283 if (!enable)
284 ser |= 1 << spi->chip_select;
285 else
286 ser &= ~(1 << spi->chip_select);
287
288 writel_relaxed(ser, rs->regs + ROCKCHIP_SPI_SER);
289
290 pm_runtime_put_sync(rs->dev);
291}
292
293static int rockchip_spi_prepare_message(struct spi_master *master,
294 struct spi_message *msg)
295{
296 struct rockchip_spi *rs = spi_master_get_devdata(master);
297 struct spi_device *spi = msg->spi;
298
299 rs->mode = spi->mode;
300
301 return 0;
302}
303
304static void rockchip_spi_handle_err(struct spi_master *master,
305 struct spi_message *msg)
306{
307 unsigned long flags;
308 struct rockchip_spi *rs = spi_master_get_devdata(master);
309
310 spin_lock_irqsave(&rs->lock, flags);
311
312 /*
313 * For DMA mode, we need terminate DMA channel and flush
314 * fifo for the next transfer if DMA thansfer timeout.
315 * handle_err() was called by core if transfer failed.
316 * Maybe it is reasonable for error handling here.
317 */
318 if (rs->use_dma) {
319 if (rs->state & RXBUSY) {
320 dmaengine_terminate_async(rs->dma_rx.ch);
321 flush_fifo(rs);
322 }
323
324 if (rs->state & TXBUSY)
325 dmaengine_terminate_async(rs->dma_tx.ch);
326 }
327
328 spin_unlock_irqrestore(&rs->lock, flags);
329}
330
331static int rockchip_spi_unprepare_message(struct spi_master *master,
332 struct spi_message *msg)
333{
334 struct rockchip_spi *rs = spi_master_get_devdata(master);
335
336 spi_enable_chip(rs, 0);
337
338 return 0;
339}
340
341static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
342{
343 u32 max = tx_max(rs);
344 u32 txw = 0;
345
346 while (max--) {
347 if (rs->n_bytes == 1)
348 txw = *(u8 *)(rs->tx);
349 else
350 txw = *(u16 *)(rs->tx);
351
352 writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR);
353 rs->tx += rs->n_bytes;
354 }
355}
356
357static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
358{
359 u32 max = rx_max(rs);
360 u32 rxw;
361
362 while (max--) {
363 rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
364 if (rs->n_bytes == 1)
365 *(u8 *)(rs->rx) = (u8)rxw;
366 else
367 *(u16 *)(rs->rx) = (u16)rxw;
368 rs->rx += rs->n_bytes;
369 }
370}
371
372static int rockchip_spi_pio_transfer(struct rockchip_spi *rs)
373{
374 int remain = 0;
375
376 do {
377 if (rs->tx) {
378 remain = rs->tx_end - rs->tx;
379 rockchip_spi_pio_writer(rs);
380 }
381
382 if (rs->rx) {
383 remain = rs->rx_end - rs->rx;
384 rockchip_spi_pio_reader(rs);
385 }
386
387 cpu_relax();
388 } while (remain);
389
390 /* If tx, wait until the FIFO data completely. */
391 if (rs->tx)
392 wait_for_idle(rs);
393
394 spi_enable_chip(rs, 0);
395
396 return 0;
397}
398
399static void rockchip_spi_dma_rxcb(void *data)
400{
401 unsigned long flags;
402 struct rockchip_spi *rs = data;
403
404 spin_lock_irqsave(&rs->lock, flags);
405
406 rs->state &= ~RXBUSY;
407 if (!(rs->state & TXBUSY)) {
408 spi_enable_chip(rs, 0);
409 spi_finalize_current_transfer(rs->master);
410 }
411
412 spin_unlock_irqrestore(&rs->lock, flags);
413}
414
415static void rockchip_spi_dma_txcb(void *data)
416{
417 unsigned long flags;
418 struct rockchip_spi *rs = data;
419
420 /* Wait until the FIFO data completely. */
421 wait_for_idle(rs);
422
423 spin_lock_irqsave(&rs->lock, flags);
424
425 rs->state &= ~TXBUSY;
426 if (!(rs->state & RXBUSY)) {
427 spi_enable_chip(rs, 0);
428 spi_finalize_current_transfer(rs->master);
429 }
430
431 spin_unlock_irqrestore(&rs->lock, flags);
432}
433
434static int rockchip_spi_prepare_dma(struct rockchip_spi *rs)
435{
436 unsigned long flags;
437 struct dma_slave_config rxconf, txconf;
438 struct dma_async_tx_descriptor *rxdesc, *txdesc;
439
440 spin_lock_irqsave(&rs->lock, flags);
441 rs->state &= ~RXBUSY;
442 rs->state &= ~TXBUSY;
443 spin_unlock_irqrestore(&rs->lock, flags);
444
445 rxdesc = NULL;
446 if (rs->rx) {
447 rxconf.direction = rs->dma_rx.direction;
448 rxconf.src_addr = rs->dma_rx.addr;
449 rxconf.src_addr_width = rs->n_bytes;
450 if (rs->dma_caps.max_burst > 4)
451 rxconf.src_maxburst = 4;
452 else
453 rxconf.src_maxburst = 1;
454 dmaengine_slave_config(rs->dma_rx.ch, &rxconf);
455
456 rxdesc = dmaengine_prep_slave_sg(
457 rs->dma_rx.ch,
458 rs->rx_sg.sgl, rs->rx_sg.nents,
459 rs->dma_rx.direction, DMA_PREP_INTERRUPT);
460 if (!rxdesc)
461 return -EINVAL;
462
463 rxdesc->callback = rockchip_spi_dma_rxcb;
464 rxdesc->callback_param = rs;
465 }
466
467 txdesc = NULL;
468 if (rs->tx) {
469 txconf.direction = rs->dma_tx.direction;
470 txconf.dst_addr = rs->dma_tx.addr;
471 txconf.dst_addr_width = rs->n_bytes;
472 if (rs->dma_caps.max_burst > 4)
473 txconf.dst_maxburst = 4;
474 else
475 txconf.dst_maxburst = 1;
476 dmaengine_slave_config(rs->dma_tx.ch, &txconf);
477
478 txdesc = dmaengine_prep_slave_sg(
479 rs->dma_tx.ch,
480 rs->tx_sg.sgl, rs->tx_sg.nents,
481 rs->dma_tx.direction, DMA_PREP_INTERRUPT);
482 if (!txdesc) {
483 if (rxdesc)
484 dmaengine_terminate_sync(rs->dma_rx.ch);
485 return -EINVAL;
486 }
487
488 txdesc->callback = rockchip_spi_dma_txcb;
489 txdesc->callback_param = rs;
490 }
491
492 /* rx must be started before tx due to spi instinct */
493 if (rxdesc) {
494 spin_lock_irqsave(&rs->lock, flags);
495 rs->state |= RXBUSY;
496 spin_unlock_irqrestore(&rs->lock, flags);
497 dmaengine_submit(rxdesc);
498 dma_async_issue_pending(rs->dma_rx.ch);
499 }
500
501 if (txdesc) {
502 spin_lock_irqsave(&rs->lock, flags);
503 rs->state |= TXBUSY;
504 spin_unlock_irqrestore(&rs->lock, flags);
505 dmaengine_submit(txdesc);
506 dma_async_issue_pending(rs->dma_tx.ch);
507 }
508
509 return 0;
510}
511
512static void rockchip_spi_config(struct rockchip_spi *rs)
513{
514 u32 div = 0;
515 u32 dmacr = 0;
516 int rsd = 0;
517
518 u32 cr0 = (CR0_BHT_8BIT << CR0_BHT_OFFSET)
519 | (CR0_SSD_ONE << CR0_SSD_OFFSET)
520 | (CR0_EM_BIG << CR0_EM_OFFSET);
521
522 cr0 |= (rs->n_bytes << CR0_DFS_OFFSET);
523 cr0 |= ((rs->mode & 0x3) << CR0_SCPH_OFFSET);
524 cr0 |= (rs->tmode << CR0_XFM_OFFSET);
525 cr0 |= (rs->type << CR0_FRF_OFFSET);
526
527 if (rs->use_dma) {
528 if (rs->tx)
529 dmacr |= TF_DMA_EN;
530 if (rs->rx)
531 dmacr |= RF_DMA_EN;
532 }
533
534 if (WARN_ON(rs->speed > MAX_SCLK_OUT))
535 rs->speed = MAX_SCLK_OUT;
536
537 /* the minimum divisor is 2 */
538 if (rs->max_freq < 2 * rs->speed) {
539 clk_set_rate(rs->spiclk, 2 * rs->speed);
540 rs->max_freq = clk_get_rate(rs->spiclk);
541 }
542
543 /* div doesn't support odd number */
544 div = DIV_ROUND_UP(rs->max_freq, rs->speed);
545 div = (div + 1) & 0xfffe;
546
547 /* Rx sample delay is expressed in parent clock cycles (max 3) */
548 rsd = DIV_ROUND_CLOSEST(rs->rsd_nsecs * (rs->max_freq >> 8),
549 1000000000 >> 8);
550 if (!rsd && rs->rsd_nsecs) {
551 pr_warn_once("rockchip-spi: %u Hz are too slow to express %u ns delay\n",
552 rs->max_freq, rs->rsd_nsecs);
553 } else if (rsd > 3) {
554 rsd = 3;
555 pr_warn_once("rockchip-spi: %u Hz are too fast to express %u ns delay, clamping at %u ns\n",
556 rs->max_freq, rs->rsd_nsecs,
557 rsd * 1000000000U / rs->max_freq);
558 }
559 cr0 |= rsd << CR0_RSD_OFFSET;
560
561 writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
562
563 writel_relaxed(rs->len - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
564 writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR);
565 writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
566
567 writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR);
568 writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR);
569 writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
570
571 spi_set_clk(rs, div);
572
573 dev_dbg(rs->dev, "cr0 0x%x, div %d\n", cr0, div);
574}
575
576static int rockchip_spi_transfer_one(
577 struct spi_master *master,
578 struct spi_device *spi,
579 struct spi_transfer *xfer)
580{
581 int ret = 1;
582 struct rockchip_spi *rs = spi_master_get_devdata(master);
583
584 WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
585 (readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));
586
587 if (!xfer->tx_buf && !xfer->rx_buf) {
588 dev_err(rs->dev, "No buffer for transfer\n");
589 return -EINVAL;
590 }
591
592 rs->speed = xfer->speed_hz;
593 rs->bpw = xfer->bits_per_word;
594 rs->n_bytes = rs->bpw >> 3;
595
596 rs->tx = xfer->tx_buf;
597 rs->tx_end = rs->tx + xfer->len;
598 rs->rx = xfer->rx_buf;
599 rs->rx_end = rs->rx + xfer->len;
600 rs->len = xfer->len;
601
602 rs->tx_sg = xfer->tx_sg;
603 rs->rx_sg = xfer->rx_sg;
604
605 if (rs->tx && rs->rx)
606 rs->tmode = CR0_XFM_TR;
607 else if (rs->tx)
608 rs->tmode = CR0_XFM_TO;
609 else if (rs->rx)
610 rs->tmode = CR0_XFM_RO;
611
612 /* we need prepare dma before spi was enabled */
613 if (master->can_dma && master->can_dma(master, spi, xfer))
614 rs->use_dma = 1;
615 else
616 rs->use_dma = 0;
617
618 rockchip_spi_config(rs);
619
620 if (rs->use_dma) {
621 if (rs->tmode == CR0_XFM_RO) {
622 /* rx: dma must be prepared first */
623 ret = rockchip_spi_prepare_dma(rs);
624 spi_enable_chip(rs, 1);
625 } else {
626 /* tx or tr: spi must be enabled first */
627 spi_enable_chip(rs, 1);
628 ret = rockchip_spi_prepare_dma(rs);
629 }
630 } else {
631 spi_enable_chip(rs, 1);
632 ret = rockchip_spi_pio_transfer(rs);
633 }
634
635 return ret;
636}
637
638static bool rockchip_spi_can_dma(struct spi_master *master,
639 struct spi_device *spi,
640 struct spi_transfer *xfer)
641{
642 struct rockchip_spi *rs = spi_master_get_devdata(master);
643
644 return (xfer->len > rs->fifo_len);
645}
646
647static int rockchip_spi_probe(struct platform_device *pdev)
648{
649 int ret = 0;
650 struct rockchip_spi *rs;
651 struct spi_master *master;
652 struct resource *mem;
653 u32 rsd_nsecs;
654
655 master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
656 if (!master)
657 return -ENOMEM;
658
659 platform_set_drvdata(pdev, master);
660
661 rs = spi_master_get_devdata(master);
662
663 /* Get basic io resource and map it */
664 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
665 rs->regs = devm_ioremap_resource(&pdev->dev, mem);
666 if (IS_ERR(rs->regs)) {
667 ret = PTR_ERR(rs->regs);
668 goto err_ioremap_resource;
669 }
670
671 rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
672 if (IS_ERR(rs->apb_pclk)) {
673 dev_err(&pdev->dev, "Failed to get apb_pclk\n");
674 ret = PTR_ERR(rs->apb_pclk);
675 goto err_ioremap_resource;
676 }
677
678 rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
679 if (IS_ERR(rs->spiclk)) {
680 dev_err(&pdev->dev, "Failed to get spi_pclk\n");
681 ret = PTR_ERR(rs->spiclk);
682 goto err_ioremap_resource;
683 }
684
685 ret = clk_prepare_enable(rs->apb_pclk);
686 if (ret) {
687 dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
688 goto err_ioremap_resource;
689 }
690
691 ret = clk_prepare_enable(rs->spiclk);
692 if (ret) {
693 dev_err(&pdev->dev, "Failed to enable spi_clk\n");
694 goto err_spiclk_enable;
695 }
696
697 spi_enable_chip(rs, 0);
698
699 rs->type = SSI_MOTO_SPI;
700 rs->master = master;
701 rs->dev = &pdev->dev;
702 rs->max_freq = clk_get_rate(rs->spiclk);
703
704 if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns",
705 &rsd_nsecs))
706 rs->rsd_nsecs = rsd_nsecs;
707
708 rs->fifo_len = get_fifo_len(rs);
709 if (!rs->fifo_len) {
710 dev_err(&pdev->dev, "Failed to get fifo length\n");
711 ret = -EINVAL;
712 goto err_get_fifo_len;
713 }
714
715 spin_lock_init(&rs->lock);
716
717 pm_runtime_set_active(&pdev->dev);
718 pm_runtime_enable(&pdev->dev);
719
720 master->auto_runtime_pm = true;
721 master->bus_num = pdev->id;
722 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
723 master->num_chipselect = 2;
724 master->dev.of_node = pdev->dev.of_node;
725 master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
726
727 master->set_cs = rockchip_spi_set_cs;
728 master->prepare_message = rockchip_spi_prepare_message;
729 master->unprepare_message = rockchip_spi_unprepare_message;
730 master->transfer_one = rockchip_spi_transfer_one;
731 master->handle_err = rockchip_spi_handle_err;
732
733 rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
734 if (IS_ERR(rs->dma_tx.ch)) {
735 /* Check tx to see if we need defer probing driver */
736 if (PTR_ERR(rs->dma_tx.ch) == -EPROBE_DEFER) {
737 ret = -EPROBE_DEFER;
738 goto err_get_fifo_len;
739 }
740 dev_warn(rs->dev, "Failed to request TX DMA channel\n");
741 rs->dma_tx.ch = NULL;
742 }
743
744 rs->dma_rx.ch = dma_request_chan(rs->dev, "rx");
745 if (IS_ERR(rs->dma_rx.ch)) {
746 if (PTR_ERR(rs->dma_rx.ch) == -EPROBE_DEFER) {
747 dma_release_channel(rs->dma_tx.ch);
748 rs->dma_tx.ch = NULL;
749 ret = -EPROBE_DEFER;
750 goto err_get_fifo_len;
751 }
752 dev_warn(rs->dev, "Failed to request RX DMA channel\n");
753 rs->dma_rx.ch = NULL;
754 }
755
756 if (rs->dma_tx.ch && rs->dma_rx.ch) {
757 dma_get_slave_caps(rs->dma_rx.ch, &(rs->dma_caps));
758 rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR);
759 rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR);
760 rs->dma_tx.direction = DMA_MEM_TO_DEV;
761 rs->dma_rx.direction = DMA_DEV_TO_MEM;
762
763 master->can_dma = rockchip_spi_can_dma;
764 master->dma_tx = rs->dma_tx.ch;
765 master->dma_rx = rs->dma_rx.ch;
766 }
767
768 ret = devm_spi_register_master(&pdev->dev, master);
769 if (ret) {
770 dev_err(&pdev->dev, "Failed to register master\n");
771 goto err_register_master;
772 }
773
774 return 0;
775
776err_register_master:
777 pm_runtime_disable(&pdev->dev);
778 if (rs->dma_tx.ch)
779 dma_release_channel(rs->dma_tx.ch);
780 if (rs->dma_rx.ch)
781 dma_release_channel(rs->dma_rx.ch);
782err_get_fifo_len:
783 clk_disable_unprepare(rs->spiclk);
784err_spiclk_enable:
785 clk_disable_unprepare(rs->apb_pclk);
786err_ioremap_resource:
787 spi_master_put(master);
788
789 return ret;
790}
791
792static int rockchip_spi_remove(struct platform_device *pdev)
793{
794 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
795 struct rockchip_spi *rs = spi_master_get_devdata(master);
796
797 pm_runtime_disable(&pdev->dev);
798
799 clk_disable_unprepare(rs->spiclk);
800 clk_disable_unprepare(rs->apb_pclk);
801
802 if (rs->dma_tx.ch)
803 dma_release_channel(rs->dma_tx.ch);
804 if (rs->dma_rx.ch)
805 dma_release_channel(rs->dma_rx.ch);
806
807 spi_master_put(master);
808
809 return 0;
810}
811
812#ifdef CONFIG_PM_SLEEP
813static int rockchip_spi_suspend(struct device *dev)
814{
815 int ret = 0;
816 struct spi_master *master = dev_get_drvdata(dev);
817 struct rockchip_spi *rs = spi_master_get_devdata(master);
818
819 ret = spi_master_suspend(rs->master);
820 if (ret)
821 return ret;
822
823 if (!pm_runtime_suspended(dev)) {
824 clk_disable_unprepare(rs->spiclk);
825 clk_disable_unprepare(rs->apb_pclk);
826 }
827
828 return ret;
829}
830
831static int rockchip_spi_resume(struct device *dev)
832{
833 int ret = 0;
834 struct spi_master *master = dev_get_drvdata(dev);
835 struct rockchip_spi *rs = spi_master_get_devdata(master);
836
837 if (!pm_runtime_suspended(dev)) {
838 ret = clk_prepare_enable(rs->apb_pclk);
839 if (ret < 0)
840 return ret;
841
842 ret = clk_prepare_enable(rs->spiclk);
843 if (ret < 0) {
844 clk_disable_unprepare(rs->apb_pclk);
845 return ret;
846 }
847 }
848
849 ret = spi_master_resume(rs->master);
850 if (ret < 0) {
851 clk_disable_unprepare(rs->spiclk);
852 clk_disable_unprepare(rs->apb_pclk);
853 }
854
855 return ret;
856}
857#endif /* CONFIG_PM_SLEEP */
858
859#ifdef CONFIG_PM
860static int rockchip_spi_runtime_suspend(struct device *dev)
861{
862 struct spi_master *master = dev_get_drvdata(dev);
863 struct rockchip_spi *rs = spi_master_get_devdata(master);
864
865 clk_disable_unprepare(rs->spiclk);
866 clk_disable_unprepare(rs->apb_pclk);
867
868 return 0;
869}
870
871static int rockchip_spi_runtime_resume(struct device *dev)
872{
873 int ret;
874 struct spi_master *master = dev_get_drvdata(dev);
875 struct rockchip_spi *rs = spi_master_get_devdata(master);
876
877 ret = clk_prepare_enable(rs->apb_pclk);
878 if (ret)
879 return ret;
880
881 ret = clk_prepare_enable(rs->spiclk);
882 if (ret)
883 clk_disable_unprepare(rs->apb_pclk);
884
885 return ret;
886}
887#endif /* CONFIG_PM */
888
889static const struct dev_pm_ops rockchip_spi_pm = {
890 SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
891 SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
892 rockchip_spi_runtime_resume, NULL)
893};
894
895static const struct of_device_id rockchip_spi_dt_match[] = {
896 { .compatible = "rockchip,rk3066-spi", },
897 { .compatible = "rockchip,rk3188-spi", },
898 { .compatible = "rockchip,rk3288-spi", },
899 { .compatible = "rockchip,rk3399-spi", },
900 { },
901};
902MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
903
904static struct platform_driver rockchip_spi_driver = {
905 .driver = {
906 .name = DRIVER_NAME,
907 .pm = &rockchip_spi_pm,
908 .of_match_table = of_match_ptr(rockchip_spi_dt_match),
909 },
910 .probe = rockchip_spi_probe,
911 .remove = rockchip_spi_remove,
912};
913
914module_platform_driver(rockchip_spi_driver);
915
916MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
917MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
918MODULE_LICENSE("GPL v2");
1/*
2 * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
3 * Author: Addy Ke <addy.ke@rock-chips.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 */
15
16#include <linux/clk.h>
17#include <linux/dmaengine.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/pinctrl/consumer.h>
21#include <linux/platform_device.h>
22#include <linux/spi/spi.h>
23#include <linux/pm_runtime.h>
24#include <linux/scatterlist.h>
25
26#define DRIVER_NAME "rockchip-spi"
27
28#define ROCKCHIP_SPI_CLR_BITS(reg, bits) \
29 writel_relaxed(readl_relaxed(reg) & ~(bits), reg)
30#define ROCKCHIP_SPI_SET_BITS(reg, bits) \
31 writel_relaxed(readl_relaxed(reg) | (bits), reg)
32
33/* SPI register offsets */
34#define ROCKCHIP_SPI_CTRLR0 0x0000
35#define ROCKCHIP_SPI_CTRLR1 0x0004
36#define ROCKCHIP_SPI_SSIENR 0x0008
37#define ROCKCHIP_SPI_SER 0x000c
38#define ROCKCHIP_SPI_BAUDR 0x0010
39#define ROCKCHIP_SPI_TXFTLR 0x0014
40#define ROCKCHIP_SPI_RXFTLR 0x0018
41#define ROCKCHIP_SPI_TXFLR 0x001c
42#define ROCKCHIP_SPI_RXFLR 0x0020
43#define ROCKCHIP_SPI_SR 0x0024
44#define ROCKCHIP_SPI_IPR 0x0028
45#define ROCKCHIP_SPI_IMR 0x002c
46#define ROCKCHIP_SPI_ISR 0x0030
47#define ROCKCHIP_SPI_RISR 0x0034
48#define ROCKCHIP_SPI_ICR 0x0038
49#define ROCKCHIP_SPI_DMACR 0x003c
50#define ROCKCHIP_SPI_DMATDLR 0x0040
51#define ROCKCHIP_SPI_DMARDLR 0x0044
52#define ROCKCHIP_SPI_TXDR 0x0400
53#define ROCKCHIP_SPI_RXDR 0x0800
54
55/* Bit fields in CTRLR0 */
56#define CR0_DFS_OFFSET 0
57
58#define CR0_CFS_OFFSET 2
59
60#define CR0_SCPH_OFFSET 6
61
62#define CR0_SCPOL_OFFSET 7
63
64#define CR0_CSM_OFFSET 8
65#define CR0_CSM_KEEP 0x0
66/* ss_n be high for half sclk_out cycles */
67#define CR0_CSM_HALF 0X1
68/* ss_n be high for one sclk_out cycle */
69#define CR0_CSM_ONE 0x2
70
71/* ss_n to sclk_out delay */
72#define CR0_SSD_OFFSET 10
73/*
74 * The period between ss_n active and
75 * sclk_out active is half sclk_out cycles
76 */
77#define CR0_SSD_HALF 0x0
78/*
79 * The period between ss_n active and
80 * sclk_out active is one sclk_out cycle
81 */
82#define CR0_SSD_ONE 0x1
83
84#define CR0_EM_OFFSET 11
85#define CR0_EM_LITTLE 0x0
86#define CR0_EM_BIG 0x1
87
88#define CR0_FBM_OFFSET 12
89#define CR0_FBM_MSB 0x0
90#define CR0_FBM_LSB 0x1
91
92#define CR0_BHT_OFFSET 13
93#define CR0_BHT_16BIT 0x0
94#define CR0_BHT_8BIT 0x1
95
96#define CR0_RSD_OFFSET 14
97
98#define CR0_FRF_OFFSET 16
99#define CR0_FRF_SPI 0x0
100#define CR0_FRF_SSP 0x1
101#define CR0_FRF_MICROWIRE 0x2
102
103#define CR0_XFM_OFFSET 18
104#define CR0_XFM_MASK (0x03 << SPI_XFM_OFFSET)
105#define CR0_XFM_TR 0x0
106#define CR0_XFM_TO 0x1
107#define CR0_XFM_RO 0x2
108
109#define CR0_OPM_OFFSET 20
110#define CR0_OPM_MASTER 0x0
111#define CR0_OPM_SLAVE 0x1
112
113#define CR0_MTM_OFFSET 0x21
114
115/* Bit fields in SER, 2bit */
116#define SER_MASK 0x3
117
118/* Bit fields in SR, 5bit */
119#define SR_MASK 0x1f
120#define SR_BUSY (1 << 0)
121#define SR_TF_FULL (1 << 1)
122#define SR_TF_EMPTY (1 << 2)
123#define SR_RF_EMPTY (1 << 3)
124#define SR_RF_FULL (1 << 4)
125
126/* Bit fields in ISR, IMR, ISR, RISR, 5bit */
127#define INT_MASK 0x1f
128#define INT_TF_EMPTY (1 << 0)
129#define INT_TF_OVERFLOW (1 << 1)
130#define INT_RF_UNDERFLOW (1 << 2)
131#define INT_RF_OVERFLOW (1 << 3)
132#define INT_RF_FULL (1 << 4)
133
134/* Bit fields in ICR, 4bit */
135#define ICR_MASK 0x0f
136#define ICR_ALL (1 << 0)
137#define ICR_RF_UNDERFLOW (1 << 1)
138#define ICR_RF_OVERFLOW (1 << 2)
139#define ICR_TF_OVERFLOW (1 << 3)
140
141/* Bit fields in DMACR */
142#define RF_DMA_EN (1 << 0)
143#define TF_DMA_EN (1 << 1)
144
145#define RXBUSY (1 << 0)
146#define TXBUSY (1 << 1)
147
148/* sclk_out: spi master internal logic in rk3x can support 50Mhz */
149#define MAX_SCLK_OUT 50000000
150
151/*
152 * SPI_CTRLR1 is 16-bits, so we should support lengths of 0xffff + 1. However,
153 * the controller seems to hang when given 0x10000, so stick with this for now.
154 */
155#define ROCKCHIP_SPI_MAX_TRANLEN 0xffff
156
157#define ROCKCHIP_SPI_MAX_CS_NUM 2
158
159enum rockchip_ssi_type {
160 SSI_MOTO_SPI = 0,
161 SSI_TI_SSP,
162 SSI_NS_MICROWIRE,
163};
164
165struct rockchip_spi_dma_data {
166 struct dma_chan *ch;
167 enum dma_transfer_direction direction;
168 dma_addr_t addr;
169};
170
171struct rockchip_spi {
172 struct device *dev;
173 struct spi_master *master;
174
175 struct clk *spiclk;
176 struct clk *apb_pclk;
177
178 void __iomem *regs;
179 /*depth of the FIFO buffer */
180 u32 fifo_len;
181 /* max bus freq supported */
182 u32 max_freq;
183 /* supported slave numbers */
184 enum rockchip_ssi_type type;
185
186 u16 mode;
187 u8 tmode;
188 u8 bpw;
189 u8 n_bytes;
190 u32 rsd_nsecs;
191 unsigned len;
192 u32 speed;
193
194 const void *tx;
195 const void *tx_end;
196 void *rx;
197 void *rx_end;
198
199 u32 state;
200 /* protect state */
201 spinlock_t lock;
202
203 bool cs_asserted[ROCKCHIP_SPI_MAX_CS_NUM];
204
205 u32 use_dma;
206 struct sg_table tx_sg;
207 struct sg_table rx_sg;
208 struct rockchip_spi_dma_data dma_rx;
209 struct rockchip_spi_dma_data dma_tx;
210 struct dma_slave_caps dma_caps;
211};
212
213static inline void spi_enable_chip(struct rockchip_spi *rs, int enable)
214{
215 writel_relaxed((enable ? 1 : 0), rs->regs + ROCKCHIP_SPI_SSIENR);
216}
217
218static inline void spi_set_clk(struct rockchip_spi *rs, u16 div)
219{
220 writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR);
221}
222
223static inline void flush_fifo(struct rockchip_spi *rs)
224{
225 while (readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR))
226 readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
227}
228
229static inline void wait_for_idle(struct rockchip_spi *rs)
230{
231 unsigned long timeout = jiffies + msecs_to_jiffies(5);
232
233 do {
234 if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))
235 return;
236 } while (!time_after(jiffies, timeout));
237
238 dev_warn(rs->dev, "spi controller is in busy state!\n");
239}
240
241static u32 get_fifo_len(struct rockchip_spi *rs)
242{
243 u32 fifo;
244
245 for (fifo = 2; fifo < 32; fifo++) {
246 writel_relaxed(fifo, rs->regs + ROCKCHIP_SPI_TXFTLR);
247 if (fifo != readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFTLR))
248 break;
249 }
250
251 writel_relaxed(0, rs->regs + ROCKCHIP_SPI_TXFTLR);
252
253 return (fifo == 31) ? 0 : fifo;
254}
255
256static inline u32 tx_max(struct rockchip_spi *rs)
257{
258 u32 tx_left, tx_room;
259
260 tx_left = (rs->tx_end - rs->tx) / rs->n_bytes;
261 tx_room = rs->fifo_len - readl_relaxed(rs->regs + ROCKCHIP_SPI_TXFLR);
262
263 return min(tx_left, tx_room);
264}
265
266static inline u32 rx_max(struct rockchip_spi *rs)
267{
268 u32 rx_left = (rs->rx_end - rs->rx) / rs->n_bytes;
269 u32 rx_room = (u32)readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR);
270
271 return min(rx_left, rx_room);
272}
273
274static void rockchip_spi_set_cs(struct spi_device *spi, bool enable)
275{
276 struct spi_master *master = spi->master;
277 struct rockchip_spi *rs = spi_master_get_devdata(master);
278 bool cs_asserted = !enable;
279
280 /* Return immediately for no-op */
281 if (cs_asserted == rs->cs_asserted[spi->chip_select])
282 return;
283
284 if (cs_asserted) {
285 /* Keep things powered as long as CS is asserted */
286 pm_runtime_get_sync(rs->dev);
287
288 ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER,
289 BIT(spi->chip_select));
290 } else {
291 ROCKCHIP_SPI_CLR_BITS(rs->regs + ROCKCHIP_SPI_SER,
292 BIT(spi->chip_select));
293
294 /* Drop reference from when we first asserted CS */
295 pm_runtime_put(rs->dev);
296 }
297
298 rs->cs_asserted[spi->chip_select] = cs_asserted;
299}
300
301static int rockchip_spi_prepare_message(struct spi_master *master,
302 struct spi_message *msg)
303{
304 struct rockchip_spi *rs = spi_master_get_devdata(master);
305 struct spi_device *spi = msg->spi;
306
307 rs->mode = spi->mode;
308
309 return 0;
310}
311
312static void rockchip_spi_handle_err(struct spi_master *master,
313 struct spi_message *msg)
314{
315 unsigned long flags;
316 struct rockchip_spi *rs = spi_master_get_devdata(master);
317
318 spin_lock_irqsave(&rs->lock, flags);
319
320 /*
321 * For DMA mode, we need terminate DMA channel and flush
322 * fifo for the next transfer if DMA thansfer timeout.
323 * handle_err() was called by core if transfer failed.
324 * Maybe it is reasonable for error handling here.
325 */
326 if (rs->use_dma) {
327 if (rs->state & RXBUSY) {
328 dmaengine_terminate_async(rs->dma_rx.ch);
329 flush_fifo(rs);
330 }
331
332 if (rs->state & TXBUSY)
333 dmaengine_terminate_async(rs->dma_tx.ch);
334 }
335
336 spin_unlock_irqrestore(&rs->lock, flags);
337}
338
339static int rockchip_spi_unprepare_message(struct spi_master *master,
340 struct spi_message *msg)
341{
342 struct rockchip_spi *rs = spi_master_get_devdata(master);
343
344 spi_enable_chip(rs, 0);
345
346 return 0;
347}
348
349static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
350{
351 u32 max = tx_max(rs);
352 u32 txw = 0;
353
354 while (max--) {
355 if (rs->n_bytes == 1)
356 txw = *(u8 *)(rs->tx);
357 else
358 txw = *(u16 *)(rs->tx);
359
360 writel_relaxed(txw, rs->regs + ROCKCHIP_SPI_TXDR);
361 rs->tx += rs->n_bytes;
362 }
363}
364
365static void rockchip_spi_pio_reader(struct rockchip_spi *rs)
366{
367 u32 max = rx_max(rs);
368 u32 rxw;
369
370 while (max--) {
371 rxw = readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
372 if (rs->n_bytes == 1)
373 *(u8 *)(rs->rx) = (u8)rxw;
374 else
375 *(u16 *)(rs->rx) = (u16)rxw;
376 rs->rx += rs->n_bytes;
377 }
378}
379
380static int rockchip_spi_pio_transfer(struct rockchip_spi *rs)
381{
382 int remain = 0;
383
384 do {
385 if (rs->tx) {
386 remain = rs->tx_end - rs->tx;
387 rockchip_spi_pio_writer(rs);
388 }
389
390 if (rs->rx) {
391 remain = rs->rx_end - rs->rx;
392 rockchip_spi_pio_reader(rs);
393 }
394
395 cpu_relax();
396 } while (remain);
397
398 /* If tx, wait until the FIFO data completely. */
399 if (rs->tx)
400 wait_for_idle(rs);
401
402 spi_enable_chip(rs, 0);
403
404 return 0;
405}
406
407static void rockchip_spi_dma_rxcb(void *data)
408{
409 unsigned long flags;
410 struct rockchip_spi *rs = data;
411
412 spin_lock_irqsave(&rs->lock, flags);
413
414 rs->state &= ~RXBUSY;
415 if (!(rs->state & TXBUSY)) {
416 spi_enable_chip(rs, 0);
417 spi_finalize_current_transfer(rs->master);
418 }
419
420 spin_unlock_irqrestore(&rs->lock, flags);
421}
422
423static void rockchip_spi_dma_txcb(void *data)
424{
425 unsigned long flags;
426 struct rockchip_spi *rs = data;
427
428 /* Wait until the FIFO data completely. */
429 wait_for_idle(rs);
430
431 spin_lock_irqsave(&rs->lock, flags);
432
433 rs->state &= ~TXBUSY;
434 if (!(rs->state & RXBUSY)) {
435 spi_enable_chip(rs, 0);
436 spi_finalize_current_transfer(rs->master);
437 }
438
439 spin_unlock_irqrestore(&rs->lock, flags);
440}
441
442static int rockchip_spi_prepare_dma(struct rockchip_spi *rs)
443{
444 unsigned long flags;
445 struct dma_slave_config rxconf, txconf;
446 struct dma_async_tx_descriptor *rxdesc, *txdesc;
447
448 spin_lock_irqsave(&rs->lock, flags);
449 rs->state &= ~RXBUSY;
450 rs->state &= ~TXBUSY;
451 spin_unlock_irqrestore(&rs->lock, flags);
452
453 rxdesc = NULL;
454 if (rs->rx) {
455 rxconf.direction = rs->dma_rx.direction;
456 rxconf.src_addr = rs->dma_rx.addr;
457 rxconf.src_addr_width = rs->n_bytes;
458 if (rs->dma_caps.max_burst > 4)
459 rxconf.src_maxburst = 4;
460 else
461 rxconf.src_maxburst = 1;
462 dmaengine_slave_config(rs->dma_rx.ch, &rxconf);
463
464 rxdesc = dmaengine_prep_slave_sg(
465 rs->dma_rx.ch,
466 rs->rx_sg.sgl, rs->rx_sg.nents,
467 rs->dma_rx.direction, DMA_PREP_INTERRUPT);
468 if (!rxdesc)
469 return -EINVAL;
470
471 rxdesc->callback = rockchip_spi_dma_rxcb;
472 rxdesc->callback_param = rs;
473 }
474
475 txdesc = NULL;
476 if (rs->tx) {
477 txconf.direction = rs->dma_tx.direction;
478 txconf.dst_addr = rs->dma_tx.addr;
479 txconf.dst_addr_width = rs->n_bytes;
480 if (rs->dma_caps.max_burst > 4)
481 txconf.dst_maxburst = 4;
482 else
483 txconf.dst_maxburst = 1;
484 dmaengine_slave_config(rs->dma_tx.ch, &txconf);
485
486 txdesc = dmaengine_prep_slave_sg(
487 rs->dma_tx.ch,
488 rs->tx_sg.sgl, rs->tx_sg.nents,
489 rs->dma_tx.direction, DMA_PREP_INTERRUPT);
490 if (!txdesc) {
491 if (rxdesc)
492 dmaengine_terminate_sync(rs->dma_rx.ch);
493 return -EINVAL;
494 }
495
496 txdesc->callback = rockchip_spi_dma_txcb;
497 txdesc->callback_param = rs;
498 }
499
500 /* rx must be started before tx due to spi instinct */
501 if (rxdesc) {
502 spin_lock_irqsave(&rs->lock, flags);
503 rs->state |= RXBUSY;
504 spin_unlock_irqrestore(&rs->lock, flags);
505 dmaengine_submit(rxdesc);
506 dma_async_issue_pending(rs->dma_rx.ch);
507 }
508
509 if (txdesc) {
510 spin_lock_irqsave(&rs->lock, flags);
511 rs->state |= TXBUSY;
512 spin_unlock_irqrestore(&rs->lock, flags);
513 dmaengine_submit(txdesc);
514 dma_async_issue_pending(rs->dma_tx.ch);
515 }
516
517 return 0;
518}
519
520static void rockchip_spi_config(struct rockchip_spi *rs)
521{
522 u32 div = 0;
523 u32 dmacr = 0;
524 int rsd = 0;
525
526 u32 cr0 = (CR0_BHT_8BIT << CR0_BHT_OFFSET)
527 | (CR0_SSD_ONE << CR0_SSD_OFFSET)
528 | (CR0_EM_BIG << CR0_EM_OFFSET);
529
530 cr0 |= (rs->n_bytes << CR0_DFS_OFFSET);
531 cr0 |= ((rs->mode & 0x3) << CR0_SCPH_OFFSET);
532 cr0 |= (rs->tmode << CR0_XFM_OFFSET);
533 cr0 |= (rs->type << CR0_FRF_OFFSET);
534
535 if (rs->use_dma) {
536 if (rs->tx)
537 dmacr |= TF_DMA_EN;
538 if (rs->rx)
539 dmacr |= RF_DMA_EN;
540 }
541
542 if (WARN_ON(rs->speed > MAX_SCLK_OUT))
543 rs->speed = MAX_SCLK_OUT;
544
545 /* the minimum divisor is 2 */
546 if (rs->max_freq < 2 * rs->speed) {
547 clk_set_rate(rs->spiclk, 2 * rs->speed);
548 rs->max_freq = clk_get_rate(rs->spiclk);
549 }
550
551 /* div doesn't support odd number */
552 div = DIV_ROUND_UP(rs->max_freq, rs->speed);
553 div = (div + 1) & 0xfffe;
554
555 /* Rx sample delay is expressed in parent clock cycles (max 3) */
556 rsd = DIV_ROUND_CLOSEST(rs->rsd_nsecs * (rs->max_freq >> 8),
557 1000000000 >> 8);
558 if (!rsd && rs->rsd_nsecs) {
559 pr_warn_once("rockchip-spi: %u Hz are too slow to express %u ns delay\n",
560 rs->max_freq, rs->rsd_nsecs);
561 } else if (rsd > 3) {
562 rsd = 3;
563 pr_warn_once("rockchip-spi: %u Hz are too fast to express %u ns delay, clamping at %u ns\n",
564 rs->max_freq, rs->rsd_nsecs,
565 rsd * 1000000000U / rs->max_freq);
566 }
567 cr0 |= rsd << CR0_RSD_OFFSET;
568
569 writel_relaxed(cr0, rs->regs + ROCKCHIP_SPI_CTRLR0);
570
571 if (rs->n_bytes == 1)
572 writel_relaxed(rs->len - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
573 else if (rs->n_bytes == 2)
574 writel_relaxed((rs->len / 2) - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
575 else
576 writel_relaxed((rs->len * 2) - 1, rs->regs + ROCKCHIP_SPI_CTRLR1);
577
578 writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_TXFTLR);
579 writel_relaxed(rs->fifo_len / 2 - 1, rs->regs + ROCKCHIP_SPI_RXFTLR);
580
581 writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMATDLR);
582 writel_relaxed(0, rs->regs + ROCKCHIP_SPI_DMARDLR);
583 writel_relaxed(dmacr, rs->regs + ROCKCHIP_SPI_DMACR);
584
585 spi_set_clk(rs, div);
586
587 dev_dbg(rs->dev, "cr0 0x%x, div %d\n", cr0, div);
588}
589
590static size_t rockchip_spi_max_transfer_size(struct spi_device *spi)
591{
592 return ROCKCHIP_SPI_MAX_TRANLEN;
593}
594
595static int rockchip_spi_transfer_one(
596 struct spi_master *master,
597 struct spi_device *spi,
598 struct spi_transfer *xfer)
599{
600 int ret = 0;
601 struct rockchip_spi *rs = spi_master_get_devdata(master);
602
603 WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
604 (readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));
605
606 if (!xfer->tx_buf && !xfer->rx_buf) {
607 dev_err(rs->dev, "No buffer for transfer\n");
608 return -EINVAL;
609 }
610
611 if (xfer->len > ROCKCHIP_SPI_MAX_TRANLEN) {
612 dev_err(rs->dev, "Transfer is too long (%d)\n", xfer->len);
613 return -EINVAL;
614 }
615
616 rs->speed = xfer->speed_hz;
617 rs->bpw = xfer->bits_per_word;
618 rs->n_bytes = rs->bpw >> 3;
619
620 rs->tx = xfer->tx_buf;
621 rs->tx_end = rs->tx + xfer->len;
622 rs->rx = xfer->rx_buf;
623 rs->rx_end = rs->rx + xfer->len;
624 rs->len = xfer->len;
625
626 rs->tx_sg = xfer->tx_sg;
627 rs->rx_sg = xfer->rx_sg;
628
629 if (rs->tx && rs->rx)
630 rs->tmode = CR0_XFM_TR;
631 else if (rs->tx)
632 rs->tmode = CR0_XFM_TO;
633 else if (rs->rx)
634 rs->tmode = CR0_XFM_RO;
635
636 /* we need prepare dma before spi was enabled */
637 if (master->can_dma && master->can_dma(master, spi, xfer))
638 rs->use_dma = 1;
639 else
640 rs->use_dma = 0;
641
642 rockchip_spi_config(rs);
643
644 if (rs->use_dma) {
645 if (rs->tmode == CR0_XFM_RO) {
646 /* rx: dma must be prepared first */
647 ret = rockchip_spi_prepare_dma(rs);
648 spi_enable_chip(rs, 1);
649 } else {
650 /* tx or tr: spi must be enabled first */
651 spi_enable_chip(rs, 1);
652 ret = rockchip_spi_prepare_dma(rs);
653 }
654 /* successful DMA prepare means the transfer is in progress */
655 ret = ret ? ret : 1;
656 } else {
657 spi_enable_chip(rs, 1);
658 ret = rockchip_spi_pio_transfer(rs);
659 }
660
661 return ret;
662}
663
664static bool rockchip_spi_can_dma(struct spi_master *master,
665 struct spi_device *spi,
666 struct spi_transfer *xfer)
667{
668 struct rockchip_spi *rs = spi_master_get_devdata(master);
669
670 return (xfer->len > rs->fifo_len);
671}
672
673static int rockchip_spi_probe(struct platform_device *pdev)
674{
675 int ret;
676 struct rockchip_spi *rs;
677 struct spi_master *master;
678 struct resource *mem;
679 u32 rsd_nsecs;
680
681 master = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));
682 if (!master)
683 return -ENOMEM;
684
685 platform_set_drvdata(pdev, master);
686
687 rs = spi_master_get_devdata(master);
688
689 /* Get basic io resource and map it */
690 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
691 rs->regs = devm_ioremap_resource(&pdev->dev, mem);
692 if (IS_ERR(rs->regs)) {
693 ret = PTR_ERR(rs->regs);
694 goto err_put_master;
695 }
696
697 rs->apb_pclk = devm_clk_get(&pdev->dev, "apb_pclk");
698 if (IS_ERR(rs->apb_pclk)) {
699 dev_err(&pdev->dev, "Failed to get apb_pclk\n");
700 ret = PTR_ERR(rs->apb_pclk);
701 goto err_put_master;
702 }
703
704 rs->spiclk = devm_clk_get(&pdev->dev, "spiclk");
705 if (IS_ERR(rs->spiclk)) {
706 dev_err(&pdev->dev, "Failed to get spi_pclk\n");
707 ret = PTR_ERR(rs->spiclk);
708 goto err_put_master;
709 }
710
711 ret = clk_prepare_enable(rs->apb_pclk);
712 if (ret < 0) {
713 dev_err(&pdev->dev, "Failed to enable apb_pclk\n");
714 goto err_put_master;
715 }
716
717 ret = clk_prepare_enable(rs->spiclk);
718 if (ret < 0) {
719 dev_err(&pdev->dev, "Failed to enable spi_clk\n");
720 goto err_disable_apbclk;
721 }
722
723 spi_enable_chip(rs, 0);
724
725 rs->type = SSI_MOTO_SPI;
726 rs->master = master;
727 rs->dev = &pdev->dev;
728 rs->max_freq = clk_get_rate(rs->spiclk);
729
730 if (!of_property_read_u32(pdev->dev.of_node, "rx-sample-delay-ns",
731 &rsd_nsecs))
732 rs->rsd_nsecs = rsd_nsecs;
733
734 rs->fifo_len = get_fifo_len(rs);
735 if (!rs->fifo_len) {
736 dev_err(&pdev->dev, "Failed to get fifo length\n");
737 ret = -EINVAL;
738 goto err_disable_spiclk;
739 }
740
741 spin_lock_init(&rs->lock);
742
743 pm_runtime_set_active(&pdev->dev);
744 pm_runtime_enable(&pdev->dev);
745
746 master->auto_runtime_pm = true;
747 master->bus_num = pdev->id;
748 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
749 master->num_chipselect = ROCKCHIP_SPI_MAX_CS_NUM;
750 master->dev.of_node = pdev->dev.of_node;
751 master->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
752
753 master->set_cs = rockchip_spi_set_cs;
754 master->prepare_message = rockchip_spi_prepare_message;
755 master->unprepare_message = rockchip_spi_unprepare_message;
756 master->transfer_one = rockchip_spi_transfer_one;
757 master->max_transfer_size = rockchip_spi_max_transfer_size;
758 master->handle_err = rockchip_spi_handle_err;
759 master->flags = SPI_MASTER_GPIO_SS;
760
761 rs->dma_tx.ch = dma_request_chan(rs->dev, "tx");
762 if (IS_ERR(rs->dma_tx.ch)) {
763 /* Check tx to see if we need defer probing driver */
764 if (PTR_ERR(rs->dma_tx.ch) == -EPROBE_DEFER) {
765 ret = -EPROBE_DEFER;
766 goto err_disable_pm_runtime;
767 }
768 dev_warn(rs->dev, "Failed to request TX DMA channel\n");
769 rs->dma_tx.ch = NULL;
770 }
771
772 rs->dma_rx.ch = dma_request_chan(rs->dev, "rx");
773 if (IS_ERR(rs->dma_rx.ch)) {
774 if (PTR_ERR(rs->dma_rx.ch) == -EPROBE_DEFER) {
775 ret = -EPROBE_DEFER;
776 goto err_free_dma_tx;
777 }
778 dev_warn(rs->dev, "Failed to request RX DMA channel\n");
779 rs->dma_rx.ch = NULL;
780 }
781
782 if (rs->dma_tx.ch && rs->dma_rx.ch) {
783 dma_get_slave_caps(rs->dma_rx.ch, &(rs->dma_caps));
784 rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR);
785 rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR);
786 rs->dma_tx.direction = DMA_MEM_TO_DEV;
787 rs->dma_rx.direction = DMA_DEV_TO_MEM;
788
789 master->can_dma = rockchip_spi_can_dma;
790 master->dma_tx = rs->dma_tx.ch;
791 master->dma_rx = rs->dma_rx.ch;
792 }
793
794 ret = devm_spi_register_master(&pdev->dev, master);
795 if (ret < 0) {
796 dev_err(&pdev->dev, "Failed to register master\n");
797 goto err_free_dma_rx;
798 }
799
800 return 0;
801
802err_free_dma_rx:
803 if (rs->dma_rx.ch)
804 dma_release_channel(rs->dma_rx.ch);
805err_free_dma_tx:
806 if (rs->dma_tx.ch)
807 dma_release_channel(rs->dma_tx.ch);
808err_disable_pm_runtime:
809 pm_runtime_disable(&pdev->dev);
810err_disable_spiclk:
811 clk_disable_unprepare(rs->spiclk);
812err_disable_apbclk:
813 clk_disable_unprepare(rs->apb_pclk);
814err_put_master:
815 spi_master_put(master);
816
817 return ret;
818}
819
820static int rockchip_spi_remove(struct platform_device *pdev)
821{
822 struct spi_master *master = spi_master_get(platform_get_drvdata(pdev));
823 struct rockchip_spi *rs = spi_master_get_devdata(master);
824
825 pm_runtime_get_sync(&pdev->dev);
826
827 clk_disable_unprepare(rs->spiclk);
828 clk_disable_unprepare(rs->apb_pclk);
829
830 pm_runtime_put_noidle(&pdev->dev);
831 pm_runtime_disable(&pdev->dev);
832 pm_runtime_set_suspended(&pdev->dev);
833
834 if (rs->dma_tx.ch)
835 dma_release_channel(rs->dma_tx.ch);
836 if (rs->dma_rx.ch)
837 dma_release_channel(rs->dma_rx.ch);
838
839 spi_master_put(master);
840
841 return 0;
842}
843
844#ifdef CONFIG_PM_SLEEP
845static int rockchip_spi_suspend(struct device *dev)
846{
847 int ret;
848 struct spi_master *master = dev_get_drvdata(dev);
849 struct rockchip_spi *rs = spi_master_get_devdata(master);
850
851 ret = spi_master_suspend(rs->master);
852 if (ret < 0)
853 return ret;
854
855 ret = pm_runtime_force_suspend(dev);
856 if (ret < 0)
857 return ret;
858
859 pinctrl_pm_select_sleep_state(dev);
860
861 return 0;
862}
863
864static int rockchip_spi_resume(struct device *dev)
865{
866 int ret;
867 struct spi_master *master = dev_get_drvdata(dev);
868 struct rockchip_spi *rs = spi_master_get_devdata(master);
869
870 pinctrl_pm_select_default_state(dev);
871
872 ret = pm_runtime_force_resume(dev);
873 if (ret < 0)
874 return ret;
875
876 ret = spi_master_resume(rs->master);
877 if (ret < 0) {
878 clk_disable_unprepare(rs->spiclk);
879 clk_disable_unprepare(rs->apb_pclk);
880 }
881
882 return 0;
883}
884#endif /* CONFIG_PM_SLEEP */
885
886#ifdef CONFIG_PM
887static int rockchip_spi_runtime_suspend(struct device *dev)
888{
889 struct spi_master *master = dev_get_drvdata(dev);
890 struct rockchip_spi *rs = spi_master_get_devdata(master);
891
892 clk_disable_unprepare(rs->spiclk);
893 clk_disable_unprepare(rs->apb_pclk);
894
895 return 0;
896}
897
898static int rockchip_spi_runtime_resume(struct device *dev)
899{
900 int ret;
901 struct spi_master *master = dev_get_drvdata(dev);
902 struct rockchip_spi *rs = spi_master_get_devdata(master);
903
904 ret = clk_prepare_enable(rs->apb_pclk);
905 if (ret < 0)
906 return ret;
907
908 ret = clk_prepare_enable(rs->spiclk);
909 if (ret < 0)
910 clk_disable_unprepare(rs->apb_pclk);
911
912 return 0;
913}
914#endif /* CONFIG_PM */
915
916static const struct dev_pm_ops rockchip_spi_pm = {
917 SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
918 SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
919 rockchip_spi_runtime_resume, NULL)
920};
921
922static const struct of_device_id rockchip_spi_dt_match[] = {
923 { .compatible = "rockchip,rv1108-spi", },
924 { .compatible = "rockchip,rk3036-spi", },
925 { .compatible = "rockchip,rk3066-spi", },
926 { .compatible = "rockchip,rk3188-spi", },
927 { .compatible = "rockchip,rk3228-spi", },
928 { .compatible = "rockchip,rk3288-spi", },
929 { .compatible = "rockchip,rk3368-spi", },
930 { .compatible = "rockchip,rk3399-spi", },
931 { },
932};
933MODULE_DEVICE_TABLE(of, rockchip_spi_dt_match);
934
935static struct platform_driver rockchip_spi_driver = {
936 .driver = {
937 .name = DRIVER_NAME,
938 .pm = &rockchip_spi_pm,
939 .of_match_table = of_match_ptr(rockchip_spi_dt_match),
940 },
941 .probe = rockchip_spi_probe,
942 .remove = rockchip_spi_remove,
943};
944
945module_platform_driver(rockchip_spi_driver);
946
947MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");
948MODULE_DESCRIPTION("ROCKCHIP SPI Controller Driver");
949MODULE_LICENSE("GPL v2");