2 * SPI driver for NVIDIA's Tegra114 SPI Controller.
4 * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 #include <linux/clk.h>
20 #include <linux/clk/tegra.h>
21 #include <linux/completion.h>
22 #include <linux/delay.h>
23 #include <linux/dmaengine.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/dmapool.h>
26 #include <linux/err.h>
27 #include <linux/init.h>
28 #include <linux/interrupt.h>
30 #include <linux/kernel.h>
31 #include <linux/kthread.h>
32 #include <linux/module.h>
33 #include <linux/platform_device.h>
34 #include <linux/pm_runtime.h>
36 #include <linux/of_device.h>
37 #include <linux/spi/spi.h>
39 #define SPI_COMMAND1 0x000
40 #define SPI_BIT_LENGTH(x) (((x) & 0x1f) << 0)
41 #define SPI_PACKED (1 << 5)
42 #define SPI_TX_EN (1 << 11)
43 #define SPI_RX_EN (1 << 12)
44 #define SPI_BOTH_EN_BYTE (1 << 13)
45 #define SPI_BOTH_EN_BIT (1 << 14)
46 #define SPI_LSBYTE_FE (1 << 15)
47 #define SPI_LSBIT_FE (1 << 16)
48 #define SPI_BIDIROE (1 << 17)
49 #define SPI_IDLE_SDA_DRIVE_LOW (0 << 18)
50 #define SPI_IDLE_SDA_DRIVE_HIGH (1 << 18)
51 #define SPI_IDLE_SDA_PULL_LOW (2 << 18)
52 #define SPI_IDLE_SDA_PULL_HIGH (3 << 18)
53 #define SPI_IDLE_SDA_MASK (3 << 18)
54 #define SPI_CS_SS_VAL (1 << 20)
55 #define SPI_CS_SW_HW (1 << 21)
56 /* SPI_CS_POL_INACTIVE bits are default high */
57 #define SPI_CS_POL_INACTIVE 22
58 #define SPI_CS_POL_INACTIVE_0 (1 << 22)
59 #define SPI_CS_POL_INACTIVE_1 (1 << 23)
60 #define SPI_CS_POL_INACTIVE_2 (1 << 24)
61 #define SPI_CS_POL_INACTIVE_3 (1 << 25)
62 #define SPI_CS_POL_INACTIVE_MASK (0xF << 22)
64 #define SPI_CS_SEL_0 (0 << 26)
65 #define SPI_CS_SEL_1 (1 << 26)
66 #define SPI_CS_SEL_2 (2 << 26)
67 #define SPI_CS_SEL_3 (3 << 26)
68 #define SPI_CS_SEL_MASK (3 << 26)
69 #define SPI_CS_SEL(x) (((x) & 0x3) << 26)
70 #define SPI_CONTROL_MODE_0 (0 << 28)
71 #define SPI_CONTROL_MODE_1 (1 << 28)
72 #define SPI_CONTROL_MODE_2 (2 << 28)
73 #define SPI_CONTROL_MODE_3 (3 << 28)
74 #define SPI_CONTROL_MODE_MASK (3 << 28)
75 #define SPI_MODE_SEL(x) (((x) & 0x3) << 28)
76 #define SPI_M_S (1 << 30)
77 #define SPI_PIO (1 << 31)
79 #define SPI_COMMAND2 0x004
80 #define SPI_TX_TAP_DELAY(x) (((x) & 0x3F) << 6)
81 #define SPI_RX_TAP_DELAY(x) (((x) & 0x3F) << 0)
83 #define SPI_CS_TIMING1 0x008
84 #define SPI_SETUP_HOLD(setup, hold) (((setup) << 4) | (hold))
85 #define SPI_CS_SETUP_HOLD(reg, cs, val) \
86 ((((val) & 0xFFu) << ((cs) * 8)) | \
87 ((reg) & ~(0xFFu << ((cs) * 8))))
89 #define SPI_CS_TIMING2 0x00C
90 #define CYCLES_BETWEEN_PACKETS_0(x) (((x) & 0x1F) << 0)
91 #define CS_ACTIVE_BETWEEN_PACKETS_0 (1 << 5)
92 #define CYCLES_BETWEEN_PACKETS_1(x) (((x) & 0x1F) << 8)
93 #define CS_ACTIVE_BETWEEN_PACKETS_1 (1 << 13)
94 #define CYCLES_BETWEEN_PACKETS_2(x) (((x) & 0x1F) << 16)
95 #define CS_ACTIVE_BETWEEN_PACKETS_2 (1 << 21)
96 #define CYCLES_BETWEEN_PACKETS_3(x) (((x) & 0x1F) << 24)
97 #define CS_ACTIVE_BETWEEN_PACKETS_3 (1 << 29)
98 #define SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(reg, cs, val) \
99 (reg = (((val) & 0x1) << ((cs) * 8 + 5)) | \
100 ((reg) & ~(1 << ((cs) * 8 + 5))))
101 #define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val) \
102 (reg = (((val) & 0xF) << ((cs) * 8)) | \
103 ((reg) & ~(0xF << ((cs) * 8))))
105 #define SPI_TRANS_STATUS 0x010
106 #define SPI_BLK_CNT(val) (((val) >> 0) & 0xFFFF)
107 #define SPI_SLV_IDLE_COUNT(val) (((val) >> 16) & 0xFF)
108 #define SPI_RDY (1 << 30)
110 #define SPI_FIFO_STATUS 0x014
111 #define SPI_RX_FIFO_EMPTY (1 << 0)
112 #define SPI_RX_FIFO_FULL (1 << 1)
113 #define SPI_TX_FIFO_EMPTY (1 << 2)
114 #define SPI_TX_FIFO_FULL (1 << 3)
115 #define SPI_RX_FIFO_UNF (1 << 4)
116 #define SPI_RX_FIFO_OVF (1 << 5)
117 #define SPI_TX_FIFO_UNF (1 << 6)
118 #define SPI_TX_FIFO_OVF (1 << 7)
119 #define SPI_ERR (1 << 8)
120 #define SPI_TX_FIFO_FLUSH (1 << 14)
121 #define SPI_RX_FIFO_FLUSH (1 << 15)
122 #define SPI_TX_FIFO_EMPTY_COUNT(val) (((val) >> 16) & 0x7F)
123 #define SPI_RX_FIFO_FULL_COUNT(val) (((val) >> 23) & 0x7F)
124 #define SPI_FRAME_END (1 << 30)
125 #define SPI_CS_INACTIVE (1 << 31)
127 #define SPI_FIFO_ERROR (SPI_RX_FIFO_UNF | \
128 SPI_RX_FIFO_OVF | SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF)
129 #define SPI_FIFO_EMPTY (SPI_RX_FIFO_EMPTY | SPI_TX_FIFO_EMPTY)
131 #define SPI_TX_DATA 0x018
132 #define SPI_RX_DATA 0x01C
134 #define SPI_DMA_CTL 0x020
135 #define SPI_TX_TRIG_1 (0 << 15)
136 #define SPI_TX_TRIG_4 (1 << 15)
137 #define SPI_TX_TRIG_8 (2 << 15)
138 #define SPI_TX_TRIG_16 (3 << 15)
139 #define SPI_TX_TRIG_MASK (3 << 15)
140 #define SPI_RX_TRIG_1 (0 << 19)
141 #define SPI_RX_TRIG_4 (1 << 19)
142 #define SPI_RX_TRIG_8 (2 << 19)
143 #define SPI_RX_TRIG_16 (3 << 19)
144 #define SPI_RX_TRIG_MASK (3 << 19)
145 #define SPI_IE_TX (1 << 28)
146 #define SPI_IE_RX (1 << 29)
147 #define SPI_CONT (1 << 30)
148 #define SPI_DMA (1 << 31)
149 #define SPI_DMA_EN SPI_DMA
151 #define SPI_DMA_BLK 0x024
152 #define SPI_DMA_BLK_SET(x) (((x) & 0xFFFF) << 0)
154 #define SPI_TX_FIFO 0x108
155 #define SPI_RX_FIFO 0x188
156 #define MAX_CHIP_SELECT 4
157 #define SPI_FIFO_DEPTH 64
158 #define DATA_DIR_TX (1 << 0)
159 #define DATA_DIR_RX (1 << 1)
161 #define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000))
162 #define DEFAULT_SPI_DMA_BUF_LEN (16*1024)
163 #define TX_FIFO_EMPTY_COUNT_MAX SPI_TX_FIFO_EMPTY_COUNT(0x40)
164 #define RX_FIFO_FULL_COUNT_ZERO SPI_RX_FIFO_FULL_COUNT(0)
165 #define MAX_HOLD_CYCLES 16
166 #define SPI_DEFAULT_SPEED 25000000
168 #define MAX_CHIP_SELECT 4
169 #define SPI_FIFO_DEPTH 64
171 struct tegra_spi_data
{
173 struct spi_master
*master
;
181 u32 spi_max_frequency
;
184 struct spi_device
*cur_spi
;
187 unsigned words_per_32bit
;
188 unsigned bytes_per_word
;
189 unsigned curr_dma_words
;
190 unsigned cur_direction
;
195 unsigned dma_buf_size
;
196 unsigned max_buf_size
;
197 bool is_curr_dma_xfer
;
199 struct completion rx_dma_complete
;
200 struct completion tx_dma_complete
;
206 unsigned long packed_size
;
210 u32 def_command1_reg
;
213 struct completion xfer_completion
;
214 struct spi_transfer
*curr_xfer
;
215 struct dma_chan
*rx_dma_chan
;
217 dma_addr_t rx_dma_phys
;
218 struct dma_async_tx_descriptor
*rx_dma_desc
;
220 struct dma_chan
*tx_dma_chan
;
222 dma_addr_t tx_dma_phys
;
223 struct dma_async_tx_descriptor
*tx_dma_desc
;
226 static int tegra_spi_runtime_suspend(struct device
*dev
);
227 static int tegra_spi_runtime_resume(struct device
*dev
);
229 static inline unsigned long tegra_spi_readl(struct tegra_spi_data
*tspi
,
232 return readl(tspi
->base
+ reg
);
235 static inline void tegra_spi_writel(struct tegra_spi_data
*tspi
,
236 unsigned long val
, unsigned long reg
)
238 writel(val
, tspi
->base
+ reg
);
240 /* Read back register to make sure that register writes completed */
241 if (reg
!= SPI_TX_FIFO
)
242 readl(tspi
->base
+ SPI_COMMAND1
);
245 static void tegra_spi_clear_status(struct tegra_spi_data
*tspi
)
249 /* Write 1 to clear status register */
250 val
= tegra_spi_readl(tspi
, SPI_TRANS_STATUS
);
251 tegra_spi_writel(tspi
, val
, SPI_TRANS_STATUS
);
253 /* Clear fifo status error if any */
254 val
= tegra_spi_readl(tspi
, SPI_FIFO_STATUS
);
256 tegra_spi_writel(tspi
, SPI_ERR
| SPI_FIFO_ERROR
,
260 static unsigned tegra_spi_calculate_curr_xfer_param(
261 struct spi_device
*spi
, struct tegra_spi_data
*tspi
,
262 struct spi_transfer
*t
)
264 unsigned remain_len
= t
->len
- tspi
->cur_pos
;
266 unsigned bits_per_word
= t
->bits_per_word
;
268 unsigned total_fifo_words
;
270 tspi
->bytes_per_word
= (bits_per_word
- 1) / 8 + 1;
272 if (bits_per_word
== 8 || bits_per_word
== 16) {
274 tspi
->words_per_32bit
= 32/bits_per_word
;
277 tspi
->words_per_32bit
= 1;
280 if (tspi
->is_packed
) {
281 max_len
= min(remain_len
, tspi
->max_buf_size
);
282 tspi
->curr_dma_words
= max_len
/tspi
->bytes_per_word
;
283 total_fifo_words
= (max_len
+ 3) / 4;
285 max_word
= (remain_len
- 1) / tspi
->bytes_per_word
+ 1;
286 max_word
= min(max_word
, tspi
->max_buf_size
/4);
287 tspi
->curr_dma_words
= max_word
;
288 total_fifo_words
= max_word
;
290 return total_fifo_words
;
293 static unsigned tegra_spi_fill_tx_fifo_from_client_txbuf(
294 struct tegra_spi_data
*tspi
, struct spi_transfer
*t
)
297 unsigned tx_empty_count
;
298 unsigned long fifo_status
;
299 unsigned max_n_32bit
;
302 unsigned int written_words
;
303 unsigned fifo_words_left
;
304 u8
*tx_buf
= (u8
*)t
->tx_buf
+ tspi
->cur_tx_pos
;
306 fifo_status
= tegra_spi_readl(tspi
, SPI_FIFO_STATUS
);
307 tx_empty_count
= SPI_TX_FIFO_EMPTY_COUNT(fifo_status
);
309 if (tspi
->is_packed
) {
310 fifo_words_left
= tx_empty_count
* tspi
->words_per_32bit
;
311 written_words
= min(fifo_words_left
, tspi
->curr_dma_words
);
312 nbytes
= written_words
* tspi
->bytes_per_word
;
313 max_n_32bit
= DIV_ROUND_UP(nbytes
, 4);
314 for (count
= 0; count
< max_n_32bit
; count
++) {
316 for (i
= 0; (i
< 4) && nbytes
; i
++, nbytes
--)
317 x
|= (*tx_buf
++) << (i
*8);
318 tegra_spi_writel(tspi
, x
, SPI_TX_FIFO
);
321 max_n_32bit
= min(tspi
->curr_dma_words
, tx_empty_count
);
322 written_words
= max_n_32bit
;
323 nbytes
= written_words
* tspi
->bytes_per_word
;
324 for (count
= 0; count
< max_n_32bit
; count
++) {
326 for (i
= 0; nbytes
&& (i
< tspi
->bytes_per_word
);
328 x
|= ((*tx_buf
++) << i
*8);
329 tegra_spi_writel(tspi
, x
, SPI_TX_FIFO
);
332 tspi
->cur_tx_pos
+= written_words
* tspi
->bytes_per_word
;
333 return written_words
;
336 static unsigned int tegra_spi_read_rx_fifo_to_client_rxbuf(
337 struct tegra_spi_data
*tspi
, struct spi_transfer
*t
)
339 unsigned rx_full_count
;
340 unsigned long fifo_status
;
343 unsigned int read_words
= 0;
345 u8
*rx_buf
= (u8
*)t
->rx_buf
+ tspi
->cur_rx_pos
;
347 fifo_status
= tegra_spi_readl(tspi
, SPI_FIFO_STATUS
);
348 rx_full_count
= SPI_RX_FIFO_FULL_COUNT(fifo_status
);
349 if (tspi
->is_packed
) {
350 len
= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
351 for (count
= 0; count
< rx_full_count
; count
++) {
352 x
= tegra_spi_readl(tspi
, SPI_RX_FIFO
);
353 for (i
= 0; len
&& (i
< 4); i
++, len
--)
354 *rx_buf
++ = (x
>> i
*8) & 0xFF;
356 tspi
->cur_rx_pos
+= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
357 read_words
+= tspi
->curr_dma_words
;
359 unsigned int rx_mask
;
360 unsigned int bits_per_word
= t
->bits_per_word
;
362 rx_mask
= (1 << bits_per_word
) - 1;
363 for (count
= 0; count
< rx_full_count
; count
++) {
364 x
= tegra_spi_readl(tspi
, SPI_RX_FIFO
);
366 for (i
= 0; (i
< tspi
->bytes_per_word
); i
++)
367 *rx_buf
++ = (x
>> (i
*8)) & 0xFF;
369 tspi
->cur_rx_pos
+= rx_full_count
* tspi
->bytes_per_word
;
370 read_words
+= rx_full_count
;
375 static void tegra_spi_copy_client_txbuf_to_spi_txbuf(
376 struct tegra_spi_data
*tspi
, struct spi_transfer
*t
)
380 /* Make the dma buffer to read by cpu */
381 dma_sync_single_for_cpu(tspi
->dev
, tspi
->tx_dma_phys
,
382 tspi
->dma_buf_size
, DMA_TO_DEVICE
);
384 if (tspi
->is_packed
) {
385 len
= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
386 memcpy(tspi
->tx_dma_buf
, t
->tx_buf
+ tspi
->cur_pos
, len
);
390 u8
*tx_buf
= (u8
*)t
->tx_buf
+ tspi
->cur_tx_pos
;
391 unsigned consume
= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
394 for (count
= 0; count
< tspi
->curr_dma_words
; count
++) {
396 for (i
= 0; consume
&& (i
< tspi
->bytes_per_word
);
398 x
|= ((*tx_buf
++) << i
* 8);
399 tspi
->tx_dma_buf
[count
] = x
;
402 tspi
->cur_tx_pos
+= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
404 /* Make the dma buffer to read by dma */
405 dma_sync_single_for_device(tspi
->dev
, tspi
->tx_dma_phys
,
406 tspi
->dma_buf_size
, DMA_TO_DEVICE
);
409 static void tegra_spi_copy_spi_rxbuf_to_client_rxbuf(
410 struct tegra_spi_data
*tspi
, struct spi_transfer
*t
)
414 /* Make the dma buffer to read by cpu */
415 dma_sync_single_for_cpu(tspi
->dev
, tspi
->rx_dma_phys
,
416 tspi
->dma_buf_size
, DMA_FROM_DEVICE
);
418 if (tspi
->is_packed
) {
419 len
= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
420 memcpy(t
->rx_buf
+ tspi
->cur_rx_pos
, tspi
->rx_dma_buf
, len
);
424 unsigned char *rx_buf
= t
->rx_buf
+ tspi
->cur_rx_pos
;
426 unsigned int rx_mask
;
427 unsigned int bits_per_word
= t
->bits_per_word
;
429 rx_mask
= (1 << bits_per_word
) - 1;
430 for (count
= 0; count
< tspi
->curr_dma_words
; count
++) {
431 x
= tspi
->rx_dma_buf
[count
];
433 for (i
= 0; (i
< tspi
->bytes_per_word
); i
++)
434 *rx_buf
++ = (x
>> (i
*8)) & 0xFF;
437 tspi
->cur_rx_pos
+= tspi
->curr_dma_words
* tspi
->bytes_per_word
;
439 /* Make the dma buffer to read by dma */
440 dma_sync_single_for_device(tspi
->dev
, tspi
->rx_dma_phys
,
441 tspi
->dma_buf_size
, DMA_FROM_DEVICE
);
444 static void tegra_spi_dma_complete(void *args
)
446 struct completion
*dma_complete
= args
;
448 complete(dma_complete
);
451 static int tegra_spi_start_tx_dma(struct tegra_spi_data
*tspi
, int len
)
453 INIT_COMPLETION(tspi
->tx_dma_complete
);
454 tspi
->tx_dma_desc
= dmaengine_prep_slave_single(tspi
->tx_dma_chan
,
455 tspi
->tx_dma_phys
, len
, DMA_MEM_TO_DEV
,
456 DMA_PREP_INTERRUPT
| DMA_CTRL_ACK
);
457 if (!tspi
->tx_dma_desc
) {
458 dev_err(tspi
->dev
, "Not able to get desc for Tx\n");
462 tspi
->tx_dma_desc
->callback
= tegra_spi_dma_complete
;
463 tspi
->tx_dma_desc
->callback_param
= &tspi
->tx_dma_complete
;
465 dmaengine_submit(tspi
->tx_dma_desc
);
466 dma_async_issue_pending(tspi
->tx_dma_chan
);
470 static int tegra_spi_start_rx_dma(struct tegra_spi_data
*tspi
, int len
)
472 INIT_COMPLETION(tspi
->rx_dma_complete
);
473 tspi
->rx_dma_desc
= dmaengine_prep_slave_single(tspi
->rx_dma_chan
,
474 tspi
->rx_dma_phys
, len
, DMA_DEV_TO_MEM
,
475 DMA_PREP_INTERRUPT
| DMA_CTRL_ACK
);
476 if (!tspi
->rx_dma_desc
) {
477 dev_err(tspi
->dev
, "Not able to get desc for Rx\n");
481 tspi
->rx_dma_desc
->callback
= tegra_spi_dma_complete
;
482 tspi
->rx_dma_desc
->callback_param
= &tspi
->rx_dma_complete
;
484 dmaengine_submit(tspi
->rx_dma_desc
);
485 dma_async_issue_pending(tspi
->rx_dma_chan
);
489 static int tegra_spi_start_dma_based_transfer(
490 struct tegra_spi_data
*tspi
, struct spi_transfer
*t
)
495 unsigned long status
;
497 /* Make sure that Rx and Tx fifo are empty */
498 status
= tegra_spi_readl(tspi
, SPI_FIFO_STATUS
);
499 if ((status
& SPI_FIFO_EMPTY
) != SPI_FIFO_EMPTY
) {
501 "Rx/Tx fifo are not empty status 0x%08lx\n", status
);
505 val
= SPI_DMA_BLK_SET(tspi
->curr_dma_words
- 1);
506 tegra_spi_writel(tspi
, val
, SPI_DMA_BLK
);
509 len
= DIV_ROUND_UP(tspi
->curr_dma_words
* tspi
->bytes_per_word
,
512 len
= tspi
->curr_dma_words
* 4;
514 /* Set attention level based on length of transfer */
516 val
|= SPI_TX_TRIG_1
| SPI_RX_TRIG_1
;
517 else if (((len
) >> 4) & 0x1)
518 val
|= SPI_TX_TRIG_4
| SPI_RX_TRIG_4
;
520 val
|= SPI_TX_TRIG_8
| SPI_RX_TRIG_8
;
522 if (tspi
->cur_direction
& DATA_DIR_TX
)
525 if (tspi
->cur_direction
& DATA_DIR_RX
)
528 tegra_spi_writel(tspi
, val
, SPI_DMA_CTL
);
529 tspi
->dma_control_reg
= val
;
531 if (tspi
->cur_direction
& DATA_DIR_TX
) {
532 tegra_spi_copy_client_txbuf_to_spi_txbuf(tspi
, t
);
533 ret
= tegra_spi_start_tx_dma(tspi
, len
);
536 "Starting tx dma failed, err %d\n", ret
);
541 if (tspi
->cur_direction
& DATA_DIR_RX
) {
542 /* Make the dma buffer to read by dma */
543 dma_sync_single_for_device(tspi
->dev
, tspi
->rx_dma_phys
,
544 tspi
->dma_buf_size
, DMA_FROM_DEVICE
);
546 ret
= tegra_spi_start_rx_dma(tspi
, len
);
549 "Starting rx dma failed, err %d\n", ret
);
550 if (tspi
->cur_direction
& DATA_DIR_TX
)
551 dmaengine_terminate_all(tspi
->tx_dma_chan
);
555 tspi
->is_curr_dma_xfer
= true;
556 tspi
->dma_control_reg
= val
;
559 tegra_spi_writel(tspi
, val
, SPI_DMA_CTL
);
563 static int tegra_spi_start_cpu_based_transfer(
564 struct tegra_spi_data
*tspi
, struct spi_transfer
*t
)
569 if (tspi
->cur_direction
& DATA_DIR_TX
)
570 cur_words
= tegra_spi_fill_tx_fifo_from_client_txbuf(tspi
, t
);
572 cur_words
= tspi
->curr_dma_words
;
574 val
= SPI_DMA_BLK_SET(cur_words
- 1);
575 tegra_spi_writel(tspi
, val
, SPI_DMA_BLK
);
578 if (tspi
->cur_direction
& DATA_DIR_TX
)
581 if (tspi
->cur_direction
& DATA_DIR_RX
)
584 tegra_spi_writel(tspi
, val
, SPI_DMA_CTL
);
585 tspi
->dma_control_reg
= val
;
587 tspi
->is_curr_dma_xfer
= false;
590 tegra_spi_writel(tspi
, val
, SPI_DMA_CTL
);
594 static int tegra_spi_init_dma_param(struct tegra_spi_data
*tspi
,
597 struct dma_chan
*dma_chan
;
601 struct dma_slave_config dma_sconfig
;
605 dma_cap_set(DMA_SLAVE
, mask
);
606 dma_chan
= dma_request_channel(mask
, NULL
, NULL
);
609 "Dma channel is not available, will try later\n");
610 return -EPROBE_DEFER
;
613 dma_buf
= dma_alloc_coherent(tspi
->dev
, tspi
->dma_buf_size
,
614 &dma_phys
, GFP_KERNEL
);
616 dev_err(tspi
->dev
, " Not able to allocate the dma buffer\n");
617 dma_release_channel(dma_chan
);
621 dma_sconfig
.slave_id
= tspi
->dma_req_sel
;
623 dma_sconfig
.src_addr
= tspi
->phys
+ SPI_RX_FIFO
;
624 dma_sconfig
.src_addr_width
= DMA_SLAVE_BUSWIDTH_4_BYTES
;
625 dma_sconfig
.src_maxburst
= 0;
627 dma_sconfig
.dst_addr
= tspi
->phys
+ SPI_TX_FIFO
;
628 dma_sconfig
.dst_addr_width
= DMA_SLAVE_BUSWIDTH_4_BYTES
;
629 dma_sconfig
.dst_maxburst
= 0;
632 ret
= dmaengine_slave_config(dma_chan
, &dma_sconfig
);
636 tspi
->rx_dma_chan
= dma_chan
;
637 tspi
->rx_dma_buf
= dma_buf
;
638 tspi
->rx_dma_phys
= dma_phys
;
640 tspi
->tx_dma_chan
= dma_chan
;
641 tspi
->tx_dma_buf
= dma_buf
;
642 tspi
->tx_dma_phys
= dma_phys
;
647 dma_free_coherent(tspi
->dev
, tspi
->dma_buf_size
, dma_buf
, dma_phys
);
648 dma_release_channel(dma_chan
);
652 static void tegra_spi_deinit_dma_param(struct tegra_spi_data
*tspi
,
657 struct dma_chan
*dma_chan
;
660 dma_buf
= tspi
->rx_dma_buf
;
661 dma_chan
= tspi
->rx_dma_chan
;
662 dma_phys
= tspi
->rx_dma_phys
;
663 tspi
->rx_dma_chan
= NULL
;
664 tspi
->rx_dma_buf
= NULL
;
666 dma_buf
= tspi
->tx_dma_buf
;
667 dma_chan
= tspi
->tx_dma_chan
;
668 dma_phys
= tspi
->tx_dma_phys
;
669 tspi
->tx_dma_buf
= NULL
;
670 tspi
->tx_dma_chan
= NULL
;
675 dma_free_coherent(tspi
->dev
, tspi
->dma_buf_size
, dma_buf
, dma_phys
);
676 dma_release_channel(dma_chan
);
679 static int tegra_spi_start_transfer_one(struct spi_device
*spi
,
680 struct spi_transfer
*t
, bool is_first_of_msg
,
683 struct tegra_spi_data
*tspi
= spi_master_get_devdata(spi
->master
);
684 u32 speed
= t
->speed_hz
;
685 u8 bits_per_word
= t
->bits_per_word
;
686 unsigned total_fifo_words
;
688 unsigned long command1
;
691 if (speed
!= tspi
->cur_speed
) {
692 clk_set_rate(tspi
->clk
, speed
);
693 tspi
->cur_speed
= speed
;
698 tspi
->cur_rx_pos
= 0;
699 tspi
->cur_tx_pos
= 0;
701 total_fifo_words
= tegra_spi_calculate_curr_xfer_param(spi
, tspi
, t
);
703 if (is_first_of_msg
) {
704 tegra_spi_clear_status(tspi
);
706 command1
= tspi
->def_command1_reg
;
707 command1
|= SPI_BIT_LENGTH(bits_per_word
- 1);
709 command1
&= ~SPI_CONTROL_MODE_MASK
;
710 req_mode
= spi
->mode
& 0x3;
711 if (req_mode
== SPI_MODE_0
)
712 command1
|= SPI_CONTROL_MODE_0
;
713 else if (req_mode
== SPI_MODE_1
)
714 command1
|= SPI_CONTROL_MODE_1
;
715 else if (req_mode
== SPI_MODE_2
)
716 command1
|= SPI_CONTROL_MODE_2
;
717 else if (req_mode
== SPI_MODE_3
)
718 command1
|= SPI_CONTROL_MODE_3
;
720 tegra_spi_writel(tspi
, command1
, SPI_COMMAND1
);
722 command1
|= SPI_CS_SW_HW
;
723 if (spi
->mode
& SPI_CS_HIGH
)
724 command1
|= SPI_CS_SS_VAL
;
726 command1
&= ~SPI_CS_SS_VAL
;
728 tegra_spi_writel(tspi
, 0, SPI_COMMAND2
);
730 command1
= tspi
->command1_reg
;
731 command1
&= ~SPI_BIT_LENGTH(~0);
732 command1
|= SPI_BIT_LENGTH(bits_per_word
- 1);
736 command1
|= SPI_PACKED
;
738 command1
&= ~(SPI_CS_SEL_MASK
| SPI_TX_EN
| SPI_RX_EN
);
739 tspi
->cur_direction
= 0;
741 command1
|= SPI_RX_EN
;
742 tspi
->cur_direction
|= DATA_DIR_RX
;
745 command1
|= SPI_TX_EN
;
746 tspi
->cur_direction
|= DATA_DIR_TX
;
748 command1
|= SPI_CS_SEL(spi
->chip_select
);
749 tegra_spi_writel(tspi
, command1
, SPI_COMMAND1
);
750 tspi
->command1_reg
= command1
;
752 dev_dbg(tspi
->dev
, "The def 0x%x and written 0x%lx\n",
753 tspi
->def_command1_reg
, command1
);
755 if (total_fifo_words
> SPI_FIFO_DEPTH
)
756 ret
= tegra_spi_start_dma_based_transfer(tspi
, t
);
758 ret
= tegra_spi_start_cpu_based_transfer(tspi
, t
);
762 static int tegra_spi_setup(struct spi_device
*spi
)
764 struct tegra_spi_data
*tspi
= spi_master_get_devdata(spi
->master
);
768 unsigned int cs_pol_bit
[MAX_CHIP_SELECT
] = {
769 SPI_CS_POL_INACTIVE_0
,
770 SPI_CS_POL_INACTIVE_1
,
771 SPI_CS_POL_INACTIVE_2
,
772 SPI_CS_POL_INACTIVE_3
,
775 dev_dbg(&spi
->dev
, "setup %d bpw, %scpol, %scpha, %dHz\n",
777 spi
->mode
& SPI_CPOL
? "" : "~",
778 spi
->mode
& SPI_CPHA
? "" : "~",
781 BUG_ON(spi
->chip_select
>= MAX_CHIP_SELECT
);
783 /* Set speed to the spi max fequency if spi device has not set */
784 spi
->max_speed_hz
= spi
->max_speed_hz
? : tspi
->spi_max_frequency
;
786 ret
= pm_runtime_get_sync(tspi
->dev
);
788 dev_err(tspi
->dev
, "pm runtime failed, e = %d\n", ret
);
792 spin_lock_irqsave(&tspi
->lock
, flags
);
793 val
= tspi
->def_command1_reg
;
794 if (spi
->mode
& SPI_CS_HIGH
)
795 val
&= ~cs_pol_bit
[spi
->chip_select
];
797 val
|= cs_pol_bit
[spi
->chip_select
];
798 tspi
->def_command1_reg
= val
;
799 tegra_spi_writel(tspi
, tspi
->def_command1_reg
, SPI_COMMAND1
);
800 spin_unlock_irqrestore(&tspi
->lock
, flags
);
802 pm_runtime_put(tspi
->dev
);
806 static int tegra_spi_transfer_one_message(struct spi_master
*master
,
807 struct spi_message
*msg
)
809 bool is_first_msg
= true;
811 struct tegra_spi_data
*tspi
= spi_master_get_devdata(master
);
812 struct spi_transfer
*xfer
;
813 struct spi_device
*spi
= msg
->spi
;
817 msg
->actual_length
= 0;
819 ret
= pm_runtime_get_sync(tspi
->dev
);
821 dev_err(tspi
->dev
, "runtime PM get failed: %d\n", ret
);
823 spi_finalize_current_message(master
);
827 single_xfer
= list_is_singular(&msg
->transfers
);
828 list_for_each_entry(xfer
, &msg
->transfers
, transfer_list
) {
829 INIT_COMPLETION(tspi
->xfer_completion
);
830 ret
= tegra_spi_start_transfer_one(spi
, xfer
,
831 is_first_msg
, single_xfer
);
834 "spi can not start transfer, err %d\n", ret
);
837 is_first_msg
= false;
838 ret
= wait_for_completion_timeout(&tspi
->xfer_completion
,
840 if (WARN_ON(ret
== 0)) {
842 "spi trasfer timeout, err %d\n", ret
);
847 if (tspi
->tx_status
|| tspi
->rx_status
) {
848 dev_err(tspi
->dev
, "Error in Transfer\n");
852 msg
->actual_length
+= xfer
->len
;
853 if (xfer
->cs_change
&& xfer
->delay_usecs
) {
854 tegra_spi_writel(tspi
, tspi
->def_command1_reg
,
856 udelay(xfer
->delay_usecs
);
861 tegra_spi_writel(tspi
, tspi
->def_command1_reg
, SPI_COMMAND1
);
862 pm_runtime_put(tspi
->dev
);
864 spi_finalize_current_message(master
);
868 static irqreturn_t
handle_cpu_based_xfer(struct tegra_spi_data
*tspi
)
870 struct spi_transfer
*t
= tspi
->curr_xfer
;
873 spin_lock_irqsave(&tspi
->lock
, flags
);
874 if (tspi
->tx_status
|| tspi
->rx_status
) {
875 dev_err(tspi
->dev
, "CpuXfer ERROR bit set 0x%x\n",
877 dev_err(tspi
->dev
, "CpuXfer 0x%08x:0x%08x\n",
878 tspi
->command1_reg
, tspi
->dma_control_reg
);
879 tegra_periph_reset_assert(tspi
->clk
);
881 tegra_periph_reset_deassert(tspi
->clk
);
882 complete(&tspi
->xfer_completion
);
886 if (tspi
->cur_direction
& DATA_DIR_RX
)
887 tegra_spi_read_rx_fifo_to_client_rxbuf(tspi
, t
);
889 if (tspi
->cur_direction
& DATA_DIR_TX
)
890 tspi
->cur_pos
= tspi
->cur_tx_pos
;
892 tspi
->cur_pos
= tspi
->cur_rx_pos
;
894 if (tspi
->cur_pos
== t
->len
) {
895 complete(&tspi
->xfer_completion
);
899 tegra_spi_calculate_curr_xfer_param(tspi
->cur_spi
, tspi
, t
);
900 tegra_spi_start_cpu_based_transfer(tspi
, t
);
902 spin_unlock_irqrestore(&tspi
->lock
, flags
);
906 static irqreturn_t
handle_dma_based_xfer(struct tegra_spi_data
*tspi
)
908 struct spi_transfer
*t
= tspi
->curr_xfer
;
911 unsigned total_fifo_words
;
914 /* Abort dmas if any error */
915 if (tspi
->cur_direction
& DATA_DIR_TX
) {
916 if (tspi
->tx_status
) {
917 dmaengine_terminate_all(tspi
->tx_dma_chan
);
920 wait_status
= wait_for_completion_interruptible_timeout(
921 &tspi
->tx_dma_complete
, SPI_DMA_TIMEOUT
);
922 if (wait_status
<= 0) {
923 dmaengine_terminate_all(tspi
->tx_dma_chan
);
924 dev_err(tspi
->dev
, "TxDma Xfer failed\n");
930 if (tspi
->cur_direction
& DATA_DIR_RX
) {
931 if (tspi
->rx_status
) {
932 dmaengine_terminate_all(tspi
->rx_dma_chan
);
935 wait_status
= wait_for_completion_interruptible_timeout(
936 &tspi
->rx_dma_complete
, SPI_DMA_TIMEOUT
);
937 if (wait_status
<= 0) {
938 dmaengine_terminate_all(tspi
->rx_dma_chan
);
939 dev_err(tspi
->dev
, "RxDma Xfer failed\n");
945 spin_lock_irqsave(&tspi
->lock
, flags
);
947 dev_err(tspi
->dev
, "DmaXfer: ERROR bit set 0x%x\n",
949 dev_err(tspi
->dev
, "DmaXfer 0x%08x:0x%08x\n",
950 tspi
->command1_reg
, tspi
->dma_control_reg
);
951 tegra_periph_reset_assert(tspi
->clk
);
953 tegra_periph_reset_deassert(tspi
->clk
);
954 complete(&tspi
->xfer_completion
);
955 spin_unlock_irqrestore(&tspi
->lock
, flags
);
959 if (tspi
->cur_direction
& DATA_DIR_RX
)
960 tegra_spi_copy_spi_rxbuf_to_client_rxbuf(tspi
, t
);
962 if (tspi
->cur_direction
& DATA_DIR_TX
)
963 tspi
->cur_pos
= tspi
->cur_tx_pos
;
965 tspi
->cur_pos
= tspi
->cur_rx_pos
;
967 if (tspi
->cur_pos
== t
->len
) {
968 complete(&tspi
->xfer_completion
);
972 /* Continue transfer in current message */
973 total_fifo_words
= tegra_spi_calculate_curr_xfer_param(tspi
->cur_spi
,
975 if (total_fifo_words
> SPI_FIFO_DEPTH
)
976 err
= tegra_spi_start_dma_based_transfer(tspi
, t
);
978 err
= tegra_spi_start_cpu_based_transfer(tspi
, t
);
981 spin_unlock_irqrestore(&tspi
->lock
, flags
);
985 static irqreturn_t
tegra_spi_isr_thread(int irq
, void *context_data
)
987 struct tegra_spi_data
*tspi
= context_data
;
989 if (!tspi
->is_curr_dma_xfer
)
990 return handle_cpu_based_xfer(tspi
);
991 return handle_dma_based_xfer(tspi
);
994 static irqreturn_t
tegra_spi_isr(int irq
, void *context_data
)
996 struct tegra_spi_data
*tspi
= context_data
;
998 tspi
->status_reg
= tegra_spi_readl(tspi
, SPI_FIFO_STATUS
);
999 if (tspi
->cur_direction
& DATA_DIR_TX
)
1000 tspi
->tx_status
= tspi
->status_reg
&
1001 (SPI_TX_FIFO_UNF
| SPI_TX_FIFO_OVF
);
1003 if (tspi
->cur_direction
& DATA_DIR_RX
)
1004 tspi
->rx_status
= tspi
->status_reg
&
1005 (SPI_RX_FIFO_OVF
| SPI_RX_FIFO_UNF
);
1006 tegra_spi_clear_status(tspi
);
1008 return IRQ_WAKE_THREAD
;
1011 static void tegra_spi_parse_dt(struct platform_device
*pdev
,
1012 struct tegra_spi_data
*tspi
)
1014 struct device_node
*np
= pdev
->dev
.of_node
;
1017 if (of_property_read_u32_array(np
, "nvidia,dma-request-selector",
1019 tspi
->dma_req_sel
= of_dma
[1];
1021 if (of_property_read_u32(np
, "spi-max-frequency",
1022 &tspi
->spi_max_frequency
))
1023 tspi
->spi_max_frequency
= 25000000; /* 25MHz */
1026 static struct of_device_id tegra_spi_of_match
[] = {
1027 { .compatible
= "nvidia,tegra114-spi", },
1030 MODULE_DEVICE_TABLE(of
, tegra_spi_of_match
);
1032 static int tegra_spi_probe(struct platform_device
*pdev
)
1034 struct spi_master
*master
;
1035 struct tegra_spi_data
*tspi
;
1039 master
= spi_alloc_master(&pdev
->dev
, sizeof(*tspi
));
1041 dev_err(&pdev
->dev
, "master allocation failed\n");
1044 dev_set_drvdata(&pdev
->dev
, master
);
1045 tspi
= spi_master_get_devdata(master
);
1048 tegra_spi_parse_dt(pdev
, tspi
);
1050 /* the spi->mode bits understood by this driver: */
1051 master
->mode_bits
= SPI_CPOL
| SPI_CPHA
| SPI_CS_HIGH
;
1052 master
->setup
= tegra_spi_setup
;
1053 master
->transfer_one_message
= tegra_spi_transfer_one_message
;
1054 master
->num_chipselect
= MAX_CHIP_SELECT
;
1055 master
->bus_num
= -1;
1057 tspi
->master
= master
;
1058 tspi
->dev
= &pdev
->dev
;
1059 spin_lock_init(&tspi
->lock
);
1061 r
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
1063 dev_err(&pdev
->dev
, "No IO memory resource\n");
1065 goto exit_free_master
;
1067 tspi
->phys
= r
->start
;
1068 tspi
->base
= devm_ioremap_resource(&pdev
->dev
, r
);
1069 if (IS_ERR(tspi
->base
)) {
1070 ret
= PTR_ERR(tspi
->base
);
1071 dev_err(&pdev
->dev
, "ioremap failed: err = %d\n", ret
);
1072 goto exit_free_master
;
1075 spi_irq
= platform_get_irq(pdev
, 0);
1076 tspi
->irq
= spi_irq
;
1077 ret
= request_threaded_irq(tspi
->irq
, tegra_spi_isr
,
1078 tegra_spi_isr_thread
, IRQF_ONESHOT
,
1079 dev_name(&pdev
->dev
), tspi
);
1081 dev_err(&pdev
->dev
, "Failed to register ISR for IRQ %d\n",
1083 goto exit_free_master
;
1086 tspi
->clk
= devm_clk_get(&pdev
->dev
, "spi");
1087 if (IS_ERR(tspi
->clk
)) {
1088 dev_err(&pdev
->dev
, "can not get clock\n");
1089 ret
= PTR_ERR(tspi
->clk
);
1093 tspi
->max_buf_size
= SPI_FIFO_DEPTH
<< 2;
1094 tspi
->dma_buf_size
= DEFAULT_SPI_DMA_BUF_LEN
;
1096 if (tspi
->dma_req_sel
) {
1097 ret
= tegra_spi_init_dma_param(tspi
, true);
1099 dev_err(&pdev
->dev
, "RxDma Init failed, err %d\n", ret
);
1103 ret
= tegra_spi_init_dma_param(tspi
, false);
1105 dev_err(&pdev
->dev
, "TxDma Init failed, err %d\n", ret
);
1106 goto exit_rx_dma_free
;
1108 tspi
->max_buf_size
= tspi
->dma_buf_size
;
1109 init_completion(&tspi
->tx_dma_complete
);
1110 init_completion(&tspi
->rx_dma_complete
);
1113 init_completion(&tspi
->xfer_completion
);
1115 pm_runtime_enable(&pdev
->dev
);
1116 if (!pm_runtime_enabled(&pdev
->dev
)) {
1117 ret
= tegra_spi_runtime_resume(&pdev
->dev
);
1119 goto exit_pm_disable
;
1122 ret
= pm_runtime_get_sync(&pdev
->dev
);
1124 dev_err(&pdev
->dev
, "pm runtime get failed, e = %d\n", ret
);
1125 goto exit_pm_disable
;
1127 tspi
->def_command1_reg
= SPI_M_S
;
1128 tegra_spi_writel(tspi
, tspi
->def_command1_reg
, SPI_COMMAND1
);
1129 pm_runtime_put(&pdev
->dev
);
1131 master
->dev
.of_node
= pdev
->dev
.of_node
;
1132 ret
= spi_register_master(master
);
1134 dev_err(&pdev
->dev
, "can not register to master err %d\n", ret
);
1135 goto exit_pm_disable
;
1140 pm_runtime_disable(&pdev
->dev
);
1141 if (!pm_runtime_status_suspended(&pdev
->dev
))
1142 tegra_spi_runtime_suspend(&pdev
->dev
);
1143 tegra_spi_deinit_dma_param(tspi
, false);
1145 tegra_spi_deinit_dma_param(tspi
, true);
1147 free_irq(spi_irq
, tspi
);
1149 spi_master_put(master
);
1153 static int tegra_spi_remove(struct platform_device
*pdev
)
1155 struct spi_master
*master
= dev_get_drvdata(&pdev
->dev
);
1156 struct tegra_spi_data
*tspi
= spi_master_get_devdata(master
);
1158 free_irq(tspi
->irq
, tspi
);
1159 spi_unregister_master(master
);
1161 if (tspi
->tx_dma_chan
)
1162 tegra_spi_deinit_dma_param(tspi
, false);
1164 if (tspi
->rx_dma_chan
)
1165 tegra_spi_deinit_dma_param(tspi
, true);
1167 pm_runtime_disable(&pdev
->dev
);
1168 if (!pm_runtime_status_suspended(&pdev
->dev
))
1169 tegra_spi_runtime_suspend(&pdev
->dev
);
1174 #ifdef CONFIG_PM_SLEEP
1175 static int tegra_spi_suspend(struct device
*dev
)
1177 struct spi_master
*master
= dev_get_drvdata(dev
);
1179 return spi_master_suspend(master
);
1182 static int tegra_spi_resume(struct device
*dev
)
1184 struct spi_master
*master
= dev_get_drvdata(dev
);
1185 struct tegra_spi_data
*tspi
= spi_master_get_devdata(master
);
1188 ret
= pm_runtime_get_sync(dev
);
1190 dev_err(dev
, "pm runtime failed, e = %d\n", ret
);
1193 tegra_spi_writel(tspi
, tspi
->command1_reg
, SPI_COMMAND1
);
1194 pm_runtime_put(dev
);
1196 return spi_master_resume(master
);
1200 static int tegra_spi_runtime_suspend(struct device
*dev
)
1202 struct spi_master
*master
= dev_get_drvdata(dev
);
1203 struct tegra_spi_data
*tspi
= spi_master_get_devdata(master
);
1205 /* Flush all write which are in PPSB queue by reading back */
1206 tegra_spi_readl(tspi
, SPI_COMMAND1
);
1208 clk_disable_unprepare(tspi
->clk
);
1212 static int tegra_spi_runtime_resume(struct device
*dev
)
1214 struct spi_master
*master
= dev_get_drvdata(dev
);
1215 struct tegra_spi_data
*tspi
= spi_master_get_devdata(master
);
1218 ret
= clk_prepare_enable(tspi
->clk
);
1220 dev_err(tspi
->dev
, "clk_prepare failed: %d\n", ret
);
1226 static const struct dev_pm_ops tegra_spi_pm_ops
= {
1227 SET_RUNTIME_PM_OPS(tegra_spi_runtime_suspend
,
1228 tegra_spi_runtime_resume
, NULL
)
1229 SET_SYSTEM_SLEEP_PM_OPS(tegra_spi_suspend
, tegra_spi_resume
)
1231 static struct platform_driver tegra_spi_driver
= {
1233 .name
= "spi-tegra114",
1234 .owner
= THIS_MODULE
,
1235 .pm
= &tegra_spi_pm_ops
,
1236 .of_match_table
= tegra_spi_of_match
,
1238 .probe
= tegra_spi_probe
,
1239 .remove
= tegra_spi_remove
,
1241 module_platform_driver(tegra_spi_driver
);
1243 MODULE_ALIAS("platform:spi-tegra114");
1244 MODULE_DESCRIPTION("NVIDIA Tegra114 SPI Controller Driver");
1245 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1246 MODULE_LICENSE("GPL v2");