blob: 413c718434927f0d3278c051d15040639a68237a [file] [log] [blame]
Laxman Dewanganf333a332013-02-22 18:07:39 +05301/*
2 * SPI driver for NVIDIA's Tegra114 SPI Controller.
3 *
4 * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved.
5 *
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.
9 *
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
13 * more details.
14 *
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/>.
17 */
18
19#include <linux/clk.h>
Laxman Dewanganf333a332013-02-22 18:07:39 +053020#include <linux/completion.h>
21#include <linux/delay.h>
22#include <linux/dmaengine.h>
23#include <linux/dma-mapping.h>
24#include <linux/dmapool.h>
25#include <linux/err.h>
26#include <linux/init.h>
27#include <linux/interrupt.h>
28#include <linux/io.h>
29#include <linux/kernel.h>
30#include <linux/kthread.h>
31#include <linux/module.h>
32#include <linux/platform_device.h>
33#include <linux/pm_runtime.h>
34#include <linux/of.h>
35#include <linux/of_device.h>
Stephen Warrenff2251e2013-11-06 16:31:24 -070036#include <linux/reset.h>
Laxman Dewanganf333a332013-02-22 18:07:39 +053037#include <linux/spi/spi.h>
38
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 */
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +010057 /* n from 0 to 3 */
58#define SPI_CS_POL_INACTIVE(n) (1 << (22 + (n)))
Laxman Dewanganf333a332013-02-22 18:07:39 +053059#define SPI_CS_POL_INACTIVE_MASK (0xF << 22)
60
61#define SPI_CS_SEL_0 (0 << 26)
62#define SPI_CS_SEL_1 (1 << 26)
63#define SPI_CS_SEL_2 (2 << 26)
64#define SPI_CS_SEL_3 (3 << 26)
65#define SPI_CS_SEL_MASK (3 << 26)
66#define SPI_CS_SEL(x) (((x) & 0x3) << 26)
67#define SPI_CONTROL_MODE_0 (0 << 28)
68#define SPI_CONTROL_MODE_1 (1 << 28)
69#define SPI_CONTROL_MODE_2 (2 << 28)
70#define SPI_CONTROL_MODE_3 (3 << 28)
71#define SPI_CONTROL_MODE_MASK (3 << 28)
72#define SPI_MODE_SEL(x) (((x) & 0x3) << 28)
73#define SPI_M_S (1 << 30)
74#define SPI_PIO (1 << 31)
75
76#define SPI_COMMAND2 0x004
77#define SPI_TX_TAP_DELAY(x) (((x) & 0x3F) << 6)
78#define SPI_RX_TAP_DELAY(x) (((x) & 0x3F) << 0)
79
80#define SPI_CS_TIMING1 0x008
81#define SPI_SETUP_HOLD(setup, hold) (((setup) << 4) | (hold))
82#define SPI_CS_SETUP_HOLD(reg, cs, val) \
83 ((((val) & 0xFFu) << ((cs) * 8)) | \
84 ((reg) & ~(0xFFu << ((cs) * 8))))
85
86#define SPI_CS_TIMING2 0x00C
87#define CYCLES_BETWEEN_PACKETS_0(x) (((x) & 0x1F) << 0)
88#define CS_ACTIVE_BETWEEN_PACKETS_0 (1 << 5)
89#define CYCLES_BETWEEN_PACKETS_1(x) (((x) & 0x1F) << 8)
90#define CS_ACTIVE_BETWEEN_PACKETS_1 (1 << 13)
91#define CYCLES_BETWEEN_PACKETS_2(x) (((x) & 0x1F) << 16)
92#define CS_ACTIVE_BETWEEN_PACKETS_2 (1 << 21)
93#define CYCLES_BETWEEN_PACKETS_3(x) (((x) & 0x1F) << 24)
94#define CS_ACTIVE_BETWEEN_PACKETS_3 (1 << 29)
95#define SPI_SET_CS_ACTIVE_BETWEEN_PACKETS(reg, cs, val) \
96 (reg = (((val) & 0x1) << ((cs) * 8 + 5)) | \
97 ((reg) & ~(1 << ((cs) * 8 + 5))))
98#define SPI_SET_CYCLES_BETWEEN_PACKETS(reg, cs, val) \
99 (reg = (((val) & 0xF) << ((cs) * 8)) | \
100 ((reg) & ~(0xF << ((cs) * 8))))
101
102#define SPI_TRANS_STATUS 0x010
103#define SPI_BLK_CNT(val) (((val) >> 0) & 0xFFFF)
104#define SPI_SLV_IDLE_COUNT(val) (((val) >> 16) & 0xFF)
105#define SPI_RDY (1 << 30)
106
107#define SPI_FIFO_STATUS 0x014
108#define SPI_RX_FIFO_EMPTY (1 << 0)
109#define SPI_RX_FIFO_FULL (1 << 1)
110#define SPI_TX_FIFO_EMPTY (1 << 2)
111#define SPI_TX_FIFO_FULL (1 << 3)
112#define SPI_RX_FIFO_UNF (1 << 4)
113#define SPI_RX_FIFO_OVF (1 << 5)
114#define SPI_TX_FIFO_UNF (1 << 6)
115#define SPI_TX_FIFO_OVF (1 << 7)
116#define SPI_ERR (1 << 8)
117#define SPI_TX_FIFO_FLUSH (1 << 14)
118#define SPI_RX_FIFO_FLUSH (1 << 15)
119#define SPI_TX_FIFO_EMPTY_COUNT(val) (((val) >> 16) & 0x7F)
120#define SPI_RX_FIFO_FULL_COUNT(val) (((val) >> 23) & 0x7F)
121#define SPI_FRAME_END (1 << 30)
122#define SPI_CS_INACTIVE (1 << 31)
123
124#define SPI_FIFO_ERROR (SPI_RX_FIFO_UNF | \
125 SPI_RX_FIFO_OVF | SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF)
126#define SPI_FIFO_EMPTY (SPI_RX_FIFO_EMPTY | SPI_TX_FIFO_EMPTY)
127
128#define SPI_TX_DATA 0x018
129#define SPI_RX_DATA 0x01C
130
131#define SPI_DMA_CTL 0x020
132#define SPI_TX_TRIG_1 (0 << 15)
133#define SPI_TX_TRIG_4 (1 << 15)
134#define SPI_TX_TRIG_8 (2 << 15)
135#define SPI_TX_TRIG_16 (3 << 15)
136#define SPI_TX_TRIG_MASK (3 << 15)
137#define SPI_RX_TRIG_1 (0 << 19)
138#define SPI_RX_TRIG_4 (1 << 19)
139#define SPI_RX_TRIG_8 (2 << 19)
140#define SPI_RX_TRIG_16 (3 << 19)
141#define SPI_RX_TRIG_MASK (3 << 19)
142#define SPI_IE_TX (1 << 28)
143#define SPI_IE_RX (1 << 29)
144#define SPI_CONT (1 << 30)
145#define SPI_DMA (1 << 31)
146#define SPI_DMA_EN SPI_DMA
147
148#define SPI_DMA_BLK 0x024
149#define SPI_DMA_BLK_SET(x) (((x) & 0xFFFF) << 0)
150
151#define SPI_TX_FIFO 0x108
152#define SPI_RX_FIFO 0x188
153#define MAX_CHIP_SELECT 4
154#define SPI_FIFO_DEPTH 64
155#define DATA_DIR_TX (1 << 0)
156#define DATA_DIR_RX (1 << 1)
157
158#define SPI_DMA_TIMEOUT (msecs_to_jiffies(1000))
159#define DEFAULT_SPI_DMA_BUF_LEN (16*1024)
160#define TX_FIFO_EMPTY_COUNT_MAX SPI_TX_FIFO_EMPTY_COUNT(0x40)
161#define RX_FIFO_FULL_COUNT_ZERO SPI_RX_FIFO_FULL_COUNT(0)
162#define MAX_HOLD_CYCLES 16
163#define SPI_DEFAULT_SPEED 25000000
164
Laxman Dewanganf333a332013-02-22 18:07:39 +0530165struct tegra_spi_data {
166 struct device *dev;
167 struct spi_master *master;
168 spinlock_t lock;
169
170 struct clk *clk;
Stephen Warrenff2251e2013-11-06 16:31:24 -0700171 struct reset_control *rst;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530172 void __iomem *base;
173 phys_addr_t phys;
174 unsigned irq;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530175 u32 spi_max_frequency;
176 u32 cur_speed;
177
178 struct spi_device *cur_spi;
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400179 struct spi_device *cs_control;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530180 unsigned cur_pos;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530181 unsigned words_per_32bit;
182 unsigned bytes_per_word;
183 unsigned curr_dma_words;
184 unsigned cur_direction;
185
186 unsigned cur_rx_pos;
187 unsigned cur_tx_pos;
188
189 unsigned dma_buf_size;
190 unsigned max_buf_size;
191 bool is_curr_dma_xfer;
192
193 struct completion rx_dma_complete;
194 struct completion tx_dma_complete;
195
196 u32 tx_status;
197 u32 rx_status;
198 u32 status_reg;
199 bool is_packed;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530200
201 u32 command1_reg;
202 u32 dma_control_reg;
203 u32 def_command1_reg;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530204
205 struct completion xfer_completion;
206 struct spi_transfer *curr_xfer;
207 struct dma_chan *rx_dma_chan;
208 u32 *rx_dma_buf;
209 dma_addr_t rx_dma_phys;
210 struct dma_async_tx_descriptor *rx_dma_desc;
211
212 struct dma_chan *tx_dma_chan;
213 u32 *tx_dma_buf;
214 dma_addr_t tx_dma_phys;
215 struct dma_async_tx_descriptor *tx_dma_desc;
216};
217
218static int tegra_spi_runtime_suspend(struct device *dev);
219static int tegra_spi_runtime_resume(struct device *dev);
220
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100221static inline u32 tegra_spi_readl(struct tegra_spi_data *tspi,
Laxman Dewanganf333a332013-02-22 18:07:39 +0530222 unsigned long reg)
223{
224 return readl(tspi->base + reg);
225}
226
227static inline void tegra_spi_writel(struct tegra_spi_data *tspi,
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100228 u32 val, unsigned long reg)
Laxman Dewanganf333a332013-02-22 18:07:39 +0530229{
230 writel(val, tspi->base + reg);
231
232 /* Read back register to make sure that register writes completed */
233 if (reg != SPI_TX_FIFO)
234 readl(tspi->base + SPI_COMMAND1);
235}
236
237static void tegra_spi_clear_status(struct tegra_spi_data *tspi)
238{
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100239 u32 val;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530240
241 /* Write 1 to clear status register */
242 val = tegra_spi_readl(tspi, SPI_TRANS_STATUS);
243 tegra_spi_writel(tspi, val, SPI_TRANS_STATUS);
244
245 /* Clear fifo status error if any */
246 val = tegra_spi_readl(tspi, SPI_FIFO_STATUS);
247 if (val & SPI_ERR)
248 tegra_spi_writel(tspi, SPI_ERR | SPI_FIFO_ERROR,
249 SPI_FIFO_STATUS);
250}
251
252static unsigned tegra_spi_calculate_curr_xfer_param(
253 struct spi_device *spi, struct tegra_spi_data *tspi,
254 struct spi_transfer *t)
255{
256 unsigned remain_len = t->len - tspi->cur_pos;
257 unsigned max_word;
258 unsigned bits_per_word = t->bits_per_word;
259 unsigned max_len;
260 unsigned total_fifo_words;
261
Axel Line91d2352013-08-30 11:00:23 +0800262 tspi->bytes_per_word = DIV_ROUND_UP(bits_per_word, 8);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530263
264 if (bits_per_word == 8 || bits_per_word == 16) {
265 tspi->is_packed = 1;
266 tspi->words_per_32bit = 32/bits_per_word;
267 } else {
268 tspi->is_packed = 0;
269 tspi->words_per_32bit = 1;
270 }
271
272 if (tspi->is_packed) {
273 max_len = min(remain_len, tspi->max_buf_size);
274 tspi->curr_dma_words = max_len/tspi->bytes_per_word;
275 total_fifo_words = (max_len + 3) / 4;
276 } else {
277 max_word = (remain_len - 1) / tspi->bytes_per_word + 1;
278 max_word = min(max_word, tspi->max_buf_size/4);
279 tspi->curr_dma_words = max_word;
280 total_fifo_words = max_word;
281 }
282 return total_fifo_words;
283}
284
285static unsigned tegra_spi_fill_tx_fifo_from_client_txbuf(
286 struct tegra_spi_data *tspi, struct spi_transfer *t)
287{
288 unsigned nbytes;
289 unsigned tx_empty_count;
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100290 u32 fifo_status;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530291 unsigned max_n_32bit;
292 unsigned i, count;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530293 unsigned int written_words;
294 unsigned fifo_words_left;
295 u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos;
296
297 fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS);
298 tx_empty_count = SPI_TX_FIFO_EMPTY_COUNT(fifo_status);
299
300 if (tspi->is_packed) {
301 fifo_words_left = tx_empty_count * tspi->words_per_32bit;
302 written_words = min(fifo_words_left, tspi->curr_dma_words);
303 nbytes = written_words * tspi->bytes_per_word;
304 max_n_32bit = DIV_ROUND_UP(nbytes, 4);
305 for (count = 0; count < max_n_32bit; count++) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100306 u32 x = 0;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530307 for (i = 0; (i < 4) && nbytes; i++, nbytes--)
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100308 x |= (u32)(*tx_buf++) << (i * 8);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530309 tegra_spi_writel(tspi, x, SPI_TX_FIFO);
310 }
311 } else {
312 max_n_32bit = min(tspi->curr_dma_words, tx_empty_count);
313 written_words = max_n_32bit;
314 nbytes = written_words * tspi->bytes_per_word;
315 for (count = 0; count < max_n_32bit; count++) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100316 u32 x = 0;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530317 for (i = 0; nbytes && (i < tspi->bytes_per_word);
318 i++, nbytes--)
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100319 x |= (u32)(*tx_buf++) << (i * 8);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530320 tegra_spi_writel(tspi, x, SPI_TX_FIFO);
321 }
322 }
323 tspi->cur_tx_pos += written_words * tspi->bytes_per_word;
324 return written_words;
325}
326
327static unsigned int tegra_spi_read_rx_fifo_to_client_rxbuf(
328 struct tegra_spi_data *tspi, struct spi_transfer *t)
329{
330 unsigned rx_full_count;
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100331 u32 fifo_status;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530332 unsigned i, count;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530333 unsigned int read_words = 0;
334 unsigned len;
335 u8 *rx_buf = (u8 *)t->rx_buf + tspi->cur_rx_pos;
336
337 fifo_status = tegra_spi_readl(tspi, SPI_FIFO_STATUS);
338 rx_full_count = SPI_RX_FIFO_FULL_COUNT(fifo_status);
339 if (tspi->is_packed) {
340 len = tspi->curr_dma_words * tspi->bytes_per_word;
341 for (count = 0; count < rx_full_count; count++) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100342 u32 x = tegra_spi_readl(tspi, SPI_RX_FIFO);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530343 for (i = 0; len && (i < 4); i++, len--)
344 *rx_buf++ = (x >> i*8) & 0xFF;
345 }
346 tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word;
347 read_words += tspi->curr_dma_words;
348 } else {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100349 u32 rx_mask = ((u32)1 << t->bits_per_word) - 1;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530350 for (count = 0; count < rx_full_count; count++) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100351 u32 x = tegra_spi_readl(tspi, SPI_RX_FIFO) & rx_mask;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530352 for (i = 0; (i < tspi->bytes_per_word); i++)
353 *rx_buf++ = (x >> (i*8)) & 0xFF;
354 }
355 tspi->cur_rx_pos += rx_full_count * tspi->bytes_per_word;
356 read_words += rx_full_count;
357 }
358 return read_words;
359}
360
361static void tegra_spi_copy_client_txbuf_to_spi_txbuf(
362 struct tegra_spi_data *tspi, struct spi_transfer *t)
363{
Laxman Dewanganf333a332013-02-22 18:07:39 +0530364 /* Make the dma buffer to read by cpu */
365 dma_sync_single_for_cpu(tspi->dev, tspi->tx_dma_phys,
366 tspi->dma_buf_size, DMA_TO_DEVICE);
367
368 if (tspi->is_packed) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100369 unsigned len = tspi->curr_dma_words * tspi->bytes_per_word;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530370 memcpy(tspi->tx_dma_buf, t->tx_buf + tspi->cur_pos, len);
371 } else {
372 unsigned int i;
373 unsigned int count;
374 u8 *tx_buf = (u8 *)t->tx_buf + tspi->cur_tx_pos;
375 unsigned consume = tspi->curr_dma_words * tspi->bytes_per_word;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530376
377 for (count = 0; count < tspi->curr_dma_words; count++) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100378 u32 x = 0;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530379 for (i = 0; consume && (i < tspi->bytes_per_word);
380 i++, consume--)
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100381 x |= (u32)(*tx_buf++) << (i * 8);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530382 tspi->tx_dma_buf[count] = x;
383 }
384 }
385 tspi->cur_tx_pos += tspi->curr_dma_words * tspi->bytes_per_word;
386
387 /* Make the dma buffer to read by dma */
388 dma_sync_single_for_device(tspi->dev, tspi->tx_dma_phys,
389 tspi->dma_buf_size, DMA_TO_DEVICE);
390}
391
392static void tegra_spi_copy_spi_rxbuf_to_client_rxbuf(
393 struct tegra_spi_data *tspi, struct spi_transfer *t)
394{
Laxman Dewanganf333a332013-02-22 18:07:39 +0530395 /* Make the dma buffer to read by cpu */
396 dma_sync_single_for_cpu(tspi->dev, tspi->rx_dma_phys,
397 tspi->dma_buf_size, DMA_FROM_DEVICE);
398
399 if (tspi->is_packed) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100400 unsigned len = tspi->curr_dma_words * tspi->bytes_per_word;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530401 memcpy(t->rx_buf + tspi->cur_rx_pos, tspi->rx_dma_buf, len);
402 } else {
403 unsigned int i;
404 unsigned int count;
405 unsigned char *rx_buf = t->rx_buf + tspi->cur_rx_pos;
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100406 u32 rx_mask = ((u32)1 << t->bits_per_word) - 1;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530407
Laxman Dewanganf333a332013-02-22 18:07:39 +0530408 for (count = 0; count < tspi->curr_dma_words; count++) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100409 u32 x = tspi->rx_dma_buf[count] & rx_mask;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530410 for (i = 0; (i < tspi->bytes_per_word); i++)
411 *rx_buf++ = (x >> (i*8)) & 0xFF;
412 }
413 }
414 tspi->cur_rx_pos += tspi->curr_dma_words * tspi->bytes_per_word;
415
416 /* Make the dma buffer to read by dma */
417 dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys,
418 tspi->dma_buf_size, DMA_FROM_DEVICE);
419}
420
421static void tegra_spi_dma_complete(void *args)
422{
423 struct completion *dma_complete = args;
424
425 complete(dma_complete);
426}
427
428static int tegra_spi_start_tx_dma(struct tegra_spi_data *tspi, int len)
429{
Wolfram Sang16735d02013-11-14 14:32:02 -0800430 reinit_completion(&tspi->tx_dma_complete);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530431 tspi->tx_dma_desc = dmaengine_prep_slave_single(tspi->tx_dma_chan,
432 tspi->tx_dma_phys, len, DMA_MEM_TO_DEV,
433 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
434 if (!tspi->tx_dma_desc) {
435 dev_err(tspi->dev, "Not able to get desc for Tx\n");
436 return -EIO;
437 }
438
439 tspi->tx_dma_desc->callback = tegra_spi_dma_complete;
440 tspi->tx_dma_desc->callback_param = &tspi->tx_dma_complete;
441
442 dmaengine_submit(tspi->tx_dma_desc);
443 dma_async_issue_pending(tspi->tx_dma_chan);
444 return 0;
445}
446
447static int tegra_spi_start_rx_dma(struct tegra_spi_data *tspi, int len)
448{
Wolfram Sang16735d02013-11-14 14:32:02 -0800449 reinit_completion(&tspi->rx_dma_complete);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530450 tspi->rx_dma_desc = dmaengine_prep_slave_single(tspi->rx_dma_chan,
451 tspi->rx_dma_phys, len, DMA_DEV_TO_MEM,
452 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
453 if (!tspi->rx_dma_desc) {
454 dev_err(tspi->dev, "Not able to get desc for Rx\n");
455 return -EIO;
456 }
457
458 tspi->rx_dma_desc->callback = tegra_spi_dma_complete;
459 tspi->rx_dma_desc->callback_param = &tspi->rx_dma_complete;
460
461 dmaengine_submit(tspi->rx_dma_desc);
462 dma_async_issue_pending(tspi->rx_dma_chan);
463 return 0;
464}
465
466static int tegra_spi_start_dma_based_transfer(
467 struct tegra_spi_data *tspi, struct spi_transfer *t)
468{
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100469 u32 val;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530470 unsigned int len;
471 int ret = 0;
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100472 u32 status;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530473
474 /* Make sure that Rx and Tx fifo are empty */
475 status = tegra_spi_readl(tspi, SPI_FIFO_STATUS);
476 if ((status & SPI_FIFO_EMPTY) != SPI_FIFO_EMPTY) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100477 dev_err(tspi->dev, "Rx/Tx fifo are not empty status 0x%08x\n",
478 (unsigned)status);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530479 return -EIO;
480 }
481
482 val = SPI_DMA_BLK_SET(tspi->curr_dma_words - 1);
483 tegra_spi_writel(tspi, val, SPI_DMA_BLK);
484
485 if (tspi->is_packed)
486 len = DIV_ROUND_UP(tspi->curr_dma_words * tspi->bytes_per_word,
487 4) * 4;
488 else
489 len = tspi->curr_dma_words * 4;
490
491 /* Set attention level based on length of transfer */
492 if (len & 0xF)
493 val |= SPI_TX_TRIG_1 | SPI_RX_TRIG_1;
494 else if (((len) >> 4) & 0x1)
495 val |= SPI_TX_TRIG_4 | SPI_RX_TRIG_4;
496 else
497 val |= SPI_TX_TRIG_8 | SPI_RX_TRIG_8;
498
499 if (tspi->cur_direction & DATA_DIR_TX)
500 val |= SPI_IE_TX;
501
502 if (tspi->cur_direction & DATA_DIR_RX)
503 val |= SPI_IE_RX;
504
505 tegra_spi_writel(tspi, val, SPI_DMA_CTL);
506 tspi->dma_control_reg = val;
507
508 if (tspi->cur_direction & DATA_DIR_TX) {
509 tegra_spi_copy_client_txbuf_to_spi_txbuf(tspi, t);
510 ret = tegra_spi_start_tx_dma(tspi, len);
511 if (ret < 0) {
512 dev_err(tspi->dev,
513 "Starting tx dma failed, err %d\n", ret);
514 return ret;
515 }
516 }
517
518 if (tspi->cur_direction & DATA_DIR_RX) {
519 /* Make the dma buffer to read by dma */
520 dma_sync_single_for_device(tspi->dev, tspi->rx_dma_phys,
521 tspi->dma_buf_size, DMA_FROM_DEVICE);
522
523 ret = tegra_spi_start_rx_dma(tspi, len);
524 if (ret < 0) {
525 dev_err(tspi->dev,
526 "Starting rx dma failed, err %d\n", ret);
527 if (tspi->cur_direction & DATA_DIR_TX)
528 dmaengine_terminate_all(tspi->tx_dma_chan);
529 return ret;
530 }
531 }
532 tspi->is_curr_dma_xfer = true;
533 tspi->dma_control_reg = val;
534
535 val |= SPI_DMA_EN;
536 tegra_spi_writel(tspi, val, SPI_DMA_CTL);
537 return ret;
538}
539
540static int tegra_spi_start_cpu_based_transfer(
541 struct tegra_spi_data *tspi, struct spi_transfer *t)
542{
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100543 u32 val;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530544 unsigned cur_words;
545
546 if (tspi->cur_direction & DATA_DIR_TX)
547 cur_words = tegra_spi_fill_tx_fifo_from_client_txbuf(tspi, t);
548 else
549 cur_words = tspi->curr_dma_words;
550
551 val = SPI_DMA_BLK_SET(cur_words - 1);
552 tegra_spi_writel(tspi, val, SPI_DMA_BLK);
553
554 val = 0;
555 if (tspi->cur_direction & DATA_DIR_TX)
556 val |= SPI_IE_TX;
557
558 if (tspi->cur_direction & DATA_DIR_RX)
559 val |= SPI_IE_RX;
560
561 tegra_spi_writel(tspi, val, SPI_DMA_CTL);
562 tspi->dma_control_reg = val;
563
564 tspi->is_curr_dma_xfer = false;
565
566 val |= SPI_DMA_EN;
567 tegra_spi_writel(tspi, val, SPI_DMA_CTL);
568 return 0;
569}
570
571static int tegra_spi_init_dma_param(struct tegra_spi_data *tspi,
572 bool dma_to_memory)
573{
574 struct dma_chan *dma_chan;
575 u32 *dma_buf;
576 dma_addr_t dma_phys;
577 int ret;
578 struct dma_slave_config dma_sconfig;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530579
Stephen Warrena915d152013-11-11 13:13:47 -0700580 dma_chan = dma_request_slave_channel_reason(tspi->dev,
581 dma_to_memory ? "rx" : "tx");
582 if (IS_ERR(dma_chan)) {
583 ret = PTR_ERR(dma_chan);
584 if (ret != -EPROBE_DEFER)
585 dev_err(tspi->dev,
586 "Dma channel is not available: %d\n", ret);
587 return ret;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530588 }
589
590 dma_buf = dma_alloc_coherent(tspi->dev, tspi->dma_buf_size,
591 &dma_phys, GFP_KERNEL);
592 if (!dma_buf) {
593 dev_err(tspi->dev, " Not able to allocate the dma buffer\n");
594 dma_release_channel(dma_chan);
595 return -ENOMEM;
596 }
597
Laxman Dewanganf333a332013-02-22 18:07:39 +0530598 if (dma_to_memory) {
599 dma_sconfig.src_addr = tspi->phys + SPI_RX_FIFO;
600 dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
601 dma_sconfig.src_maxburst = 0;
602 } else {
603 dma_sconfig.dst_addr = tspi->phys + SPI_TX_FIFO;
604 dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
605 dma_sconfig.dst_maxburst = 0;
606 }
607
608 ret = dmaengine_slave_config(dma_chan, &dma_sconfig);
609 if (ret)
610 goto scrub;
611 if (dma_to_memory) {
612 tspi->rx_dma_chan = dma_chan;
613 tspi->rx_dma_buf = dma_buf;
614 tspi->rx_dma_phys = dma_phys;
615 } else {
616 tspi->tx_dma_chan = dma_chan;
617 tspi->tx_dma_buf = dma_buf;
618 tspi->tx_dma_phys = dma_phys;
619 }
620 return 0;
621
622scrub:
623 dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys);
624 dma_release_channel(dma_chan);
625 return ret;
626}
627
628static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi,
629 bool dma_to_memory)
630{
631 u32 *dma_buf;
632 dma_addr_t dma_phys;
633 struct dma_chan *dma_chan;
634
635 if (dma_to_memory) {
636 dma_buf = tspi->rx_dma_buf;
637 dma_chan = tspi->rx_dma_chan;
638 dma_phys = tspi->rx_dma_phys;
639 tspi->rx_dma_chan = NULL;
640 tspi->rx_dma_buf = NULL;
641 } else {
642 dma_buf = tspi->tx_dma_buf;
643 dma_chan = tspi->tx_dma_chan;
644 dma_phys = tspi->tx_dma_phys;
645 tspi->tx_dma_buf = NULL;
646 tspi->tx_dma_chan = NULL;
647 }
648 if (!dma_chan)
649 return;
650
651 dma_free_coherent(tspi->dev, tspi->dma_buf_size, dma_buf, dma_phys);
652 dma_release_channel(dma_chan);
653}
654
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100655static u32 tegra_spi_setup_transfer_one(struct spi_device *spi,
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400656 struct spi_transfer *t, bool is_first_of_msg)
Laxman Dewanganf333a332013-02-22 18:07:39 +0530657{
658 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master);
659 u32 speed = t->speed_hz;
660 u8 bits_per_word = t->bits_per_word;
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100661 u32 command1;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530662 int req_mode;
663
664 if (speed != tspi->cur_speed) {
665 clk_set_rate(tspi->clk, speed);
666 tspi->cur_speed = speed;
667 }
668
669 tspi->cur_spi = spi;
670 tspi->cur_pos = 0;
671 tspi->cur_rx_pos = 0;
672 tspi->cur_tx_pos = 0;
673 tspi->curr_xfer = t;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530674
675 if (is_first_of_msg) {
676 tegra_spi_clear_status(tspi);
677
678 command1 = tspi->def_command1_reg;
679 command1 |= SPI_BIT_LENGTH(bits_per_word - 1);
680
681 command1 &= ~SPI_CONTROL_MODE_MASK;
682 req_mode = spi->mode & 0x3;
683 if (req_mode == SPI_MODE_0)
684 command1 |= SPI_CONTROL_MODE_0;
685 else if (req_mode == SPI_MODE_1)
686 command1 |= SPI_CONTROL_MODE_1;
687 else if (req_mode == SPI_MODE_2)
688 command1 |= SPI_CONTROL_MODE_2;
689 else if (req_mode == SPI_MODE_3)
690 command1 |= SPI_CONTROL_MODE_3;
691
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400692 if (tspi->cs_control) {
693 if (tspi->cs_control != spi)
694 tegra_spi_writel(tspi, command1, SPI_COMMAND1);
695 tspi->cs_control = NULL;
696 } else
697 tegra_spi_writel(tspi, command1, SPI_COMMAND1);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530698
699 command1 |= SPI_CS_SW_HW;
700 if (spi->mode & SPI_CS_HIGH)
701 command1 |= SPI_CS_SS_VAL;
702 else
703 command1 &= ~SPI_CS_SS_VAL;
704
705 tegra_spi_writel(tspi, 0, SPI_COMMAND2);
706 } else {
707 command1 = tspi->command1_reg;
708 command1 &= ~SPI_BIT_LENGTH(~0);
709 command1 |= SPI_BIT_LENGTH(bits_per_word - 1);
710 }
711
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400712 return command1;
713}
714
715static int tegra_spi_start_transfer_one(struct spi_device *spi,
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100716 struct spi_transfer *t, u32 command1)
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400717{
718 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master);
719 unsigned total_fifo_words;
720 int ret;
721
722 total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t);
723
Laxman Dewanganf333a332013-02-22 18:07:39 +0530724 if (tspi->is_packed)
725 command1 |= SPI_PACKED;
726
727 command1 &= ~(SPI_CS_SEL_MASK | SPI_TX_EN | SPI_RX_EN);
728 tspi->cur_direction = 0;
729 if (t->rx_buf) {
730 command1 |= SPI_RX_EN;
731 tspi->cur_direction |= DATA_DIR_RX;
732 }
733 if (t->tx_buf) {
734 command1 |= SPI_TX_EN;
735 tspi->cur_direction |= DATA_DIR_TX;
736 }
737 command1 |= SPI_CS_SEL(spi->chip_select);
738 tegra_spi_writel(tspi, command1, SPI_COMMAND1);
739 tspi->command1_reg = command1;
740
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100741 dev_dbg(tspi->dev, "The def 0x%x and written 0x%x\n",
742 tspi->def_command1_reg, (unsigned)command1);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530743
744 if (total_fifo_words > SPI_FIFO_DEPTH)
745 ret = tegra_spi_start_dma_based_transfer(tspi, t);
746 else
747 ret = tegra_spi_start_cpu_based_transfer(tspi, t);
748 return ret;
749}
750
751static int tegra_spi_setup(struct spi_device *spi)
752{
753 struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master);
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100754 u32 val;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530755 unsigned long flags;
756 int ret;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530757
758 dev_dbg(&spi->dev, "setup %d bpw, %scpol, %scpha, %dHz\n",
759 spi->bits_per_word,
760 spi->mode & SPI_CPOL ? "" : "~",
761 spi->mode & SPI_CPHA ? "" : "~",
762 spi->max_speed_hz);
763
764 BUG_ON(spi->chip_select >= MAX_CHIP_SELECT);
765
766 /* Set speed to the spi max fequency if spi device has not set */
767 spi->max_speed_hz = spi->max_speed_hz ? : tspi->spi_max_frequency;
768
769 ret = pm_runtime_get_sync(tspi->dev);
770 if (ret < 0) {
771 dev_err(tspi->dev, "pm runtime failed, e = %d\n", ret);
772 return ret;
773 }
774
775 spin_lock_irqsave(&tspi->lock, flags);
776 val = tspi->def_command1_reg;
777 if (spi->mode & SPI_CS_HIGH)
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100778 val &= ~SPI_CS_POL_INACTIVE(spi->chip_select);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530779 else
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100780 val |= SPI_CS_POL_INACTIVE(spi->chip_select);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530781 tspi->def_command1_reg = val;
782 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1);
783 spin_unlock_irqrestore(&tspi->lock, flags);
784
785 pm_runtime_put(tspi->dev);
786 return 0;
787}
788
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400789static void tegra_spi_transfer_delay(int delay)
790{
791 if (!delay)
792 return;
793
794 if (delay >= 1000)
795 mdelay(delay / 1000);
796
797 udelay(delay % 1000);
798}
799
Laxman Dewanganf333a332013-02-22 18:07:39 +0530800static int tegra_spi_transfer_one_message(struct spi_master *master,
801 struct spi_message *msg)
802{
803 bool is_first_msg = true;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530804 struct tegra_spi_data *tspi = spi_master_get_devdata(master);
805 struct spi_transfer *xfer;
806 struct spi_device *spi = msg->spi;
807 int ret;
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400808 bool skip = false;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530809
810 msg->status = 0;
811 msg->actual_length = 0;
812
Laxman Dewanganf333a332013-02-22 18:07:39 +0530813 list_for_each_entry(xfer, &msg->transfers, transfer_list) {
Michal Nazarewicz48c3fc92013-12-08 16:35:09 +0100814 u32 cmd1;
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400815
Wolfram Sang16735d02013-11-14 14:32:02 -0800816 reinit_completion(&tspi->xfer_completion);
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400817
818 cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg);
819
820 if (!xfer->len) {
821 ret = 0;
822 skip = true;
823 goto complete_xfer;
824 }
825
826 ret = tegra_spi_start_transfer_one(spi, xfer, cmd1);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530827 if (ret < 0) {
828 dev_err(tspi->dev,
829 "spi can not start transfer, err %d\n", ret);
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400830 goto complete_xfer;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530831 }
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400832
Laxman Dewanganf333a332013-02-22 18:07:39 +0530833 is_first_msg = false;
834 ret = wait_for_completion_timeout(&tspi->xfer_completion,
835 SPI_DMA_TIMEOUT);
836 if (WARN_ON(ret == 0)) {
837 dev_err(tspi->dev,
838 "spi trasfer timeout, err %d\n", ret);
839 ret = -EIO;
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400840 goto complete_xfer;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530841 }
842
843 if (tspi->tx_status || tspi->rx_status) {
844 dev_err(tspi->dev, "Error in Transfer\n");
845 ret = -EIO;
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400846 goto complete_xfer;
Laxman Dewanganf333a332013-02-22 18:07:39 +0530847 }
848 msg->actual_length += xfer->len;
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400849
850complete_xfer:
851 if (ret < 0 || skip) {
Laxman Dewanganf333a332013-02-22 18:07:39 +0530852 tegra_spi_writel(tspi, tspi->def_command1_reg,
853 SPI_COMMAND1);
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400854 tegra_spi_transfer_delay(xfer->delay_usecs);
855 goto exit;
856 } else if (msg->transfers.prev == &xfer->transfer_list) {
857 /* This is the last transfer in message */
858 if (xfer->cs_change)
859 tspi->cs_control = spi;
860 else {
861 tegra_spi_writel(tspi, tspi->def_command1_reg,
862 SPI_COMMAND1);
863 tegra_spi_transfer_delay(xfer->delay_usecs);
864 }
865 } else if (xfer->cs_change) {
866 tegra_spi_writel(tspi, tspi->def_command1_reg,
867 SPI_COMMAND1);
868 tegra_spi_transfer_delay(xfer->delay_usecs);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530869 }
Rhyland Kleinf4fade12013-09-26 13:01:43 -0400870
Laxman Dewanganf333a332013-02-22 18:07:39 +0530871 }
872 ret = 0;
873exit:
Laxman Dewanganf333a332013-02-22 18:07:39 +0530874 msg->status = ret;
875 spi_finalize_current_message(master);
876 return ret;
877}
878
879static irqreturn_t handle_cpu_based_xfer(struct tegra_spi_data *tspi)
880{
881 struct spi_transfer *t = tspi->curr_xfer;
882 unsigned long flags;
883
884 spin_lock_irqsave(&tspi->lock, flags);
885 if (tspi->tx_status || tspi->rx_status) {
886 dev_err(tspi->dev, "CpuXfer ERROR bit set 0x%x\n",
887 tspi->status_reg);
888 dev_err(tspi->dev, "CpuXfer 0x%08x:0x%08x\n",
889 tspi->command1_reg, tspi->dma_control_reg);
Stephen Warrenff2251e2013-11-06 16:31:24 -0700890 reset_control_assert(tspi->rst);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530891 udelay(2);
Stephen Warrenff2251e2013-11-06 16:31:24 -0700892 reset_control_deassert(tspi->rst);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530893 complete(&tspi->xfer_completion);
894 goto exit;
895 }
896
897 if (tspi->cur_direction & DATA_DIR_RX)
898 tegra_spi_read_rx_fifo_to_client_rxbuf(tspi, t);
899
900 if (tspi->cur_direction & DATA_DIR_TX)
901 tspi->cur_pos = tspi->cur_tx_pos;
902 else
903 tspi->cur_pos = tspi->cur_rx_pos;
904
905 if (tspi->cur_pos == t->len) {
906 complete(&tspi->xfer_completion);
907 goto exit;
908 }
909
910 tegra_spi_calculate_curr_xfer_param(tspi->cur_spi, tspi, t);
911 tegra_spi_start_cpu_based_transfer(tspi, t);
912exit:
913 spin_unlock_irqrestore(&tspi->lock, flags);
914 return IRQ_HANDLED;
915}
916
917static irqreturn_t handle_dma_based_xfer(struct tegra_spi_data *tspi)
918{
919 struct spi_transfer *t = tspi->curr_xfer;
920 long wait_status;
921 int err = 0;
922 unsigned total_fifo_words;
923 unsigned long flags;
924
925 /* Abort dmas if any error */
926 if (tspi->cur_direction & DATA_DIR_TX) {
927 if (tspi->tx_status) {
928 dmaengine_terminate_all(tspi->tx_dma_chan);
929 err += 1;
930 } else {
931 wait_status = wait_for_completion_interruptible_timeout(
932 &tspi->tx_dma_complete, SPI_DMA_TIMEOUT);
933 if (wait_status <= 0) {
934 dmaengine_terminate_all(tspi->tx_dma_chan);
935 dev_err(tspi->dev, "TxDma Xfer failed\n");
936 err += 1;
937 }
938 }
939 }
940
941 if (tspi->cur_direction & DATA_DIR_RX) {
942 if (tspi->rx_status) {
943 dmaengine_terminate_all(tspi->rx_dma_chan);
944 err += 2;
945 } else {
946 wait_status = wait_for_completion_interruptible_timeout(
947 &tspi->rx_dma_complete, SPI_DMA_TIMEOUT);
948 if (wait_status <= 0) {
949 dmaengine_terminate_all(tspi->rx_dma_chan);
950 dev_err(tspi->dev, "RxDma Xfer failed\n");
951 err += 2;
952 }
953 }
954 }
955
956 spin_lock_irqsave(&tspi->lock, flags);
957 if (err) {
958 dev_err(tspi->dev, "DmaXfer: ERROR bit set 0x%x\n",
959 tspi->status_reg);
960 dev_err(tspi->dev, "DmaXfer 0x%08x:0x%08x\n",
961 tspi->command1_reg, tspi->dma_control_reg);
Stephen Warrenff2251e2013-11-06 16:31:24 -0700962 reset_control_assert(tspi->rst);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530963 udelay(2);
Stephen Warrenff2251e2013-11-06 16:31:24 -0700964 reset_control_deassert(tspi->rst);
Laxman Dewanganf333a332013-02-22 18:07:39 +0530965 complete(&tspi->xfer_completion);
966 spin_unlock_irqrestore(&tspi->lock, flags);
967 return IRQ_HANDLED;
968 }
969
970 if (tspi->cur_direction & DATA_DIR_RX)
971 tegra_spi_copy_spi_rxbuf_to_client_rxbuf(tspi, t);
972
973 if (tspi->cur_direction & DATA_DIR_TX)
974 tspi->cur_pos = tspi->cur_tx_pos;
975 else
976 tspi->cur_pos = tspi->cur_rx_pos;
977
978 if (tspi->cur_pos == t->len) {
979 complete(&tspi->xfer_completion);
980 goto exit;
981 }
982
983 /* Continue transfer in current message */
984 total_fifo_words = tegra_spi_calculate_curr_xfer_param(tspi->cur_spi,
985 tspi, t);
986 if (total_fifo_words > SPI_FIFO_DEPTH)
987 err = tegra_spi_start_dma_based_transfer(tspi, t);
988 else
989 err = tegra_spi_start_cpu_based_transfer(tspi, t);
990
991exit:
992 spin_unlock_irqrestore(&tspi->lock, flags);
993 return IRQ_HANDLED;
994}
995
996static irqreturn_t tegra_spi_isr_thread(int irq, void *context_data)
997{
998 struct tegra_spi_data *tspi = context_data;
999
1000 if (!tspi->is_curr_dma_xfer)
1001 return handle_cpu_based_xfer(tspi);
1002 return handle_dma_based_xfer(tspi);
1003}
1004
1005static irqreturn_t tegra_spi_isr(int irq, void *context_data)
1006{
1007 struct tegra_spi_data *tspi = context_data;
1008
1009 tspi->status_reg = tegra_spi_readl(tspi, SPI_FIFO_STATUS);
1010 if (tspi->cur_direction & DATA_DIR_TX)
1011 tspi->tx_status = tspi->status_reg &
1012 (SPI_TX_FIFO_UNF | SPI_TX_FIFO_OVF);
1013
1014 if (tspi->cur_direction & DATA_DIR_RX)
1015 tspi->rx_status = tspi->status_reg &
1016 (SPI_RX_FIFO_OVF | SPI_RX_FIFO_UNF);
1017 tegra_spi_clear_status(tspi);
1018
1019 return IRQ_WAKE_THREAD;
1020}
1021
1022static void tegra_spi_parse_dt(struct platform_device *pdev,
1023 struct tegra_spi_data *tspi)
1024{
1025 struct device_node *np = pdev->dev.of_node;
Laxman Dewanganf333a332013-02-22 18:07:39 +05301026
1027 if (of_property_read_u32(np, "spi-max-frequency",
1028 &tspi->spi_max_frequency))
1029 tspi->spi_max_frequency = 25000000; /* 25MHz */
1030}
1031
1032static struct of_device_id tegra_spi_of_match[] = {
1033 { .compatible = "nvidia,tegra114-spi", },
1034 {}
1035};
1036MODULE_DEVICE_TABLE(of, tegra_spi_of_match);
1037
1038static int tegra_spi_probe(struct platform_device *pdev)
1039{
1040 struct spi_master *master;
1041 struct tegra_spi_data *tspi;
1042 struct resource *r;
1043 int ret, spi_irq;
1044
1045 master = spi_alloc_master(&pdev->dev, sizeof(*tspi));
1046 if (!master) {
1047 dev_err(&pdev->dev, "master allocation failed\n");
1048 return -ENOMEM;
1049 }
Jingoo Han24b5a822013-05-23 19:20:40 +09001050 platform_set_drvdata(pdev, master);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301051 tspi = spi_master_get_devdata(master);
1052
1053 /* Parse DT */
1054 tegra_spi_parse_dt(pdev, tspi);
1055
1056 /* the spi->mode bits understood by this driver: */
1057 master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1058 master->setup = tegra_spi_setup;
1059 master->transfer_one_message = tegra_spi_transfer_one_message;
1060 master->num_chipselect = MAX_CHIP_SELECT;
1061 master->bus_num = -1;
Mark Brown612aa5c2013-07-28 15:37:31 +01001062 master->auto_runtime_pm = true;
Laxman Dewanganf333a332013-02-22 18:07:39 +05301063
1064 tspi->master = master;
1065 tspi->dev = &pdev->dev;
1066 spin_lock_init(&tspi->lock);
1067
1068 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301069 tspi->base = devm_ioremap_resource(&pdev->dev, r);
1070 if (IS_ERR(tspi->base)) {
1071 ret = PTR_ERR(tspi->base);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301072 goto exit_free_master;
1073 }
Laurent Navet5f7f54b2013-05-14 12:07:12 +02001074 tspi->phys = r->start;
Laxman Dewanganf333a332013-02-22 18:07:39 +05301075
1076 spi_irq = platform_get_irq(pdev, 0);
1077 tspi->irq = spi_irq;
1078 ret = request_threaded_irq(tspi->irq, tegra_spi_isr,
1079 tegra_spi_isr_thread, IRQF_ONESHOT,
1080 dev_name(&pdev->dev), tspi);
1081 if (ret < 0) {
1082 dev_err(&pdev->dev, "Failed to register ISR for IRQ %d\n",
1083 tspi->irq);
1084 goto exit_free_master;
1085 }
1086
1087 tspi->clk = devm_clk_get(&pdev->dev, "spi");
1088 if (IS_ERR(tspi->clk)) {
1089 dev_err(&pdev->dev, "can not get clock\n");
1090 ret = PTR_ERR(tspi->clk);
1091 goto exit_free_irq;
1092 }
1093
Stephen Warrenff2251e2013-11-06 16:31:24 -07001094 tspi->rst = devm_reset_control_get(&pdev->dev, "spi");
1095 if (IS_ERR(tspi->rst)) {
1096 dev_err(&pdev->dev, "can not get reset\n");
1097 ret = PTR_ERR(tspi->rst);
1098 goto exit_free_irq;
1099 }
1100
Laxman Dewanganf333a332013-02-22 18:07:39 +05301101 tspi->max_buf_size = SPI_FIFO_DEPTH << 2;
1102 tspi->dma_buf_size = DEFAULT_SPI_DMA_BUF_LEN;
1103
Stephen Warrena915d152013-11-11 13:13:47 -07001104 ret = tegra_spi_init_dma_param(tspi, true);
1105 if (ret < 0)
1106 goto exit_free_irq;
1107 ret = tegra_spi_init_dma_param(tspi, false);
1108 if (ret < 0)
1109 goto exit_rx_dma_free;
1110 tspi->max_buf_size = tspi->dma_buf_size;
1111 init_completion(&tspi->tx_dma_complete);
1112 init_completion(&tspi->rx_dma_complete);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301113
1114 init_completion(&tspi->xfer_completion);
1115
1116 pm_runtime_enable(&pdev->dev);
1117 if (!pm_runtime_enabled(&pdev->dev)) {
1118 ret = tegra_spi_runtime_resume(&pdev->dev);
1119 if (ret)
1120 goto exit_pm_disable;
1121 }
1122
1123 ret = pm_runtime_get_sync(&pdev->dev);
1124 if (ret < 0) {
1125 dev_err(&pdev->dev, "pm runtime get failed, e = %d\n", ret);
1126 goto exit_pm_disable;
1127 }
1128 tspi->def_command1_reg = SPI_M_S;
1129 tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1);
1130 pm_runtime_put(&pdev->dev);
1131
1132 master->dev.of_node = pdev->dev.of_node;
Jingoo Han5c809642013-09-24 13:49:24 +09001133 ret = devm_spi_register_master(&pdev->dev, master);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301134 if (ret < 0) {
1135 dev_err(&pdev->dev, "can not register to master err %d\n", ret);
1136 goto exit_pm_disable;
1137 }
1138 return ret;
1139
1140exit_pm_disable:
1141 pm_runtime_disable(&pdev->dev);
1142 if (!pm_runtime_status_suspended(&pdev->dev))
1143 tegra_spi_runtime_suspend(&pdev->dev);
1144 tegra_spi_deinit_dma_param(tspi, false);
1145exit_rx_dma_free:
1146 tegra_spi_deinit_dma_param(tspi, true);
1147exit_free_irq:
1148 free_irq(spi_irq, tspi);
1149exit_free_master:
1150 spi_master_put(master);
1151 return ret;
1152}
1153
1154static int tegra_spi_remove(struct platform_device *pdev)
1155{
Jingoo Han24b5a822013-05-23 19:20:40 +09001156 struct spi_master *master = platform_get_drvdata(pdev);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301157 struct tegra_spi_data *tspi = spi_master_get_devdata(master);
1158
1159 free_irq(tspi->irq, tspi);
Laxman Dewanganf333a332013-02-22 18:07:39 +05301160
1161 if (tspi->tx_dma_chan)
1162 tegra_spi_deinit_dma_param(tspi, false);
1163
1164 if (tspi->rx_dma_chan)
1165 tegra_spi_deinit_dma_param(tspi, true);
1166
1167 pm_runtime_disable(&pdev->dev);
1168 if (!pm_runtime_status_suspended(&pdev->dev))
1169 tegra_spi_runtime_suspend(&pdev->dev);
1170
1171 return 0;
1172}
1173
1174#ifdef CONFIG_PM_SLEEP
1175static int tegra_spi_suspend(struct device *dev)
1176{
1177 struct spi_master *master = dev_get_drvdata(dev);
1178
1179 return spi_master_suspend(master);
1180}
1181
1182static int tegra_spi_resume(struct device *dev)
1183{
1184 struct spi_master *master = dev_get_drvdata(dev);
1185 struct tegra_spi_data *tspi = spi_master_get_devdata(master);
1186 int ret;
1187
1188 ret = pm_runtime_get_sync(dev);
1189 if (ret < 0) {
1190 dev_err(dev, "pm runtime failed, e = %d\n", ret);
1191 return ret;
1192 }
1193 tegra_spi_writel(tspi, tspi->command1_reg, SPI_COMMAND1);
1194 pm_runtime_put(dev);
1195
1196 return spi_master_resume(master);
1197}
1198#endif
1199
1200static int tegra_spi_runtime_suspend(struct device *dev)
1201{
1202 struct spi_master *master = dev_get_drvdata(dev);
1203 struct tegra_spi_data *tspi = spi_master_get_devdata(master);
1204
1205 /* Flush all write which are in PPSB queue by reading back */
1206 tegra_spi_readl(tspi, SPI_COMMAND1);
1207
1208 clk_disable_unprepare(tspi->clk);
1209 return 0;
1210}
1211
1212static int tegra_spi_runtime_resume(struct device *dev)
1213{
1214 struct spi_master *master = dev_get_drvdata(dev);
1215 struct tegra_spi_data *tspi = spi_master_get_devdata(master);
1216 int ret;
1217
1218 ret = clk_prepare_enable(tspi->clk);
1219 if (ret < 0) {
1220 dev_err(tspi->dev, "clk_prepare failed: %d\n", ret);
1221 return ret;
1222 }
1223 return 0;
1224}
1225
1226static 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)
1230};
1231static struct platform_driver tegra_spi_driver = {
1232 .driver = {
1233 .name = "spi-tegra114",
1234 .owner = THIS_MODULE,
1235 .pm = &tegra_spi_pm_ops,
1236 .of_match_table = tegra_spi_of_match,
1237 },
1238 .probe = tegra_spi_probe,
1239 .remove = tegra_spi_remove,
1240};
1241module_platform_driver(tegra_spi_driver);
1242
1243MODULE_ALIAS("platform:spi-tegra114");
1244MODULE_DESCRIPTION("NVIDIA Tegra114 SPI Controller Driver");
1245MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
1246MODULE_LICENSE("GPL v2");