Linux 4.2.1
[linux/fpc-iii.git] / drivers / spi / spi-imx.c
blobf9deb84e4e551bdd9c42c8ac204c80c18f0f8579
1 /*
2 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
3 * Copyright (C) 2008 Juergen Beisert
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version 2
8 * of the License, or (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the
16 * Free Software Foundation
17 * 51 Franklin Street, Fifth Floor
18 * Boston, MA 02110-1301, USA.
21 #include <linux/clk.h>
22 #include <linux/completion.h>
23 #include <linux/delay.h>
24 #include <linux/dmaengine.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/err.h>
27 #include <linux/gpio.h>
28 #include <linux/interrupt.h>
29 #include <linux/io.h>
30 #include <linux/irq.h>
31 #include <linux/kernel.h>
32 #include <linux/module.h>
33 #include <linux/platform_device.h>
34 #include <linux/slab.h>
35 #include <linux/spi/spi.h>
36 #include <linux/spi/spi_bitbang.h>
37 #include <linux/types.h>
38 #include <linux/of.h>
39 #include <linux/of_device.h>
40 #include <linux/of_gpio.h>
42 #include <linux/platform_data/dma-imx.h>
43 #include <linux/platform_data/spi-imx.h>
45 #define DRIVER_NAME "spi_imx"
47 #define MXC_CSPIRXDATA 0x00
48 #define MXC_CSPITXDATA 0x04
49 #define MXC_CSPICTRL 0x08
50 #define MXC_CSPIINT 0x0c
51 #define MXC_RESET 0x1c
53 /* generic defines to abstract from the different register layouts */
54 #define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */
55 #define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */
57 /* The maximum bytes that a sdma BD can transfer.*/
58 #define MAX_SDMA_BD_BYTES (1 << 15)
59 #define IMX_DMA_TIMEOUT (msecs_to_jiffies(3000))
60 struct spi_imx_config {
61 unsigned int speed_hz;
62 unsigned int bpw;
63 unsigned int mode;
64 u8 cs;
67 enum spi_imx_devtype {
68 IMX1_CSPI,
69 IMX21_CSPI,
70 IMX27_CSPI,
71 IMX31_CSPI,
72 IMX35_CSPI, /* CSPI on all i.mx except above */
73 IMX51_ECSPI, /* ECSPI on i.mx51 and later */
76 struct spi_imx_data;
78 struct spi_imx_devtype_data {
79 void (*intctrl)(struct spi_imx_data *, int);
80 int (*config)(struct spi_imx_data *, struct spi_imx_config *);
81 void (*trigger)(struct spi_imx_data *);
82 int (*rx_available)(struct spi_imx_data *);
83 void (*reset)(struct spi_imx_data *);
84 enum spi_imx_devtype devtype;
87 struct spi_imx_data {
88 struct spi_bitbang bitbang;
90 struct completion xfer_done;
91 void __iomem *base;
92 struct clk *clk_per;
93 struct clk *clk_ipg;
94 unsigned long spi_clk;
96 unsigned int count;
97 void (*tx)(struct spi_imx_data *);
98 void (*rx)(struct spi_imx_data *);
99 void *rx_buf;
100 const void *tx_buf;
101 unsigned int txfifo; /* number of words pushed in tx FIFO */
103 /* DMA */
104 unsigned int dma_is_inited;
105 unsigned int dma_finished;
106 bool usedma;
107 u32 rx_wml;
108 u32 tx_wml;
109 u32 rxt_wml;
110 struct completion dma_rx_completion;
111 struct completion dma_tx_completion;
113 const struct spi_imx_devtype_data *devtype_data;
114 int chipselect[0];
117 static inline int is_imx27_cspi(struct spi_imx_data *d)
119 return d->devtype_data->devtype == IMX27_CSPI;
122 static inline int is_imx35_cspi(struct spi_imx_data *d)
124 return d->devtype_data->devtype == IMX35_CSPI;
127 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
129 return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8;
132 #define MXC_SPI_BUF_RX(type) \
133 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
135 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
137 if (spi_imx->rx_buf) { \
138 *(type *)spi_imx->rx_buf = val; \
139 spi_imx->rx_buf += sizeof(type); \
143 #define MXC_SPI_BUF_TX(type) \
144 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
146 type val = 0; \
148 if (spi_imx->tx_buf) { \
149 val = *(type *)spi_imx->tx_buf; \
150 spi_imx->tx_buf += sizeof(type); \
153 spi_imx->count -= sizeof(type); \
155 writel(val, spi_imx->base + MXC_CSPITXDATA); \
158 MXC_SPI_BUF_RX(u8)
159 MXC_SPI_BUF_TX(u8)
160 MXC_SPI_BUF_RX(u16)
161 MXC_SPI_BUF_TX(u16)
162 MXC_SPI_BUF_RX(u32)
163 MXC_SPI_BUF_TX(u32)
165 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
166 * (which is currently not the case in this driver)
168 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
169 256, 384, 512, 768, 1024};
171 /* MX21, MX27 */
172 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
173 unsigned int fspi, unsigned int max)
175 int i;
177 for (i = 2; i < max; i++)
178 if (fspi * mxc_clkdivs[i] >= fin)
179 return i;
181 return max;
184 /* MX1, MX31, MX35, MX51 CSPI */
185 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
186 unsigned int fspi)
188 int i, div = 4;
190 for (i = 0; i < 7; i++) {
191 if (fspi * div >= fin)
192 return i;
193 div <<= 1;
196 return 7;
199 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
200 struct spi_transfer *transfer)
202 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
204 if (spi_imx->dma_is_inited
205 && transfer->len > spi_imx->rx_wml * sizeof(u32)
206 && transfer->len > spi_imx->tx_wml * sizeof(u32))
207 return true;
208 return false;
211 #define MX51_ECSPI_CTRL 0x08
212 #define MX51_ECSPI_CTRL_ENABLE (1 << 0)
213 #define MX51_ECSPI_CTRL_XCH (1 << 2)
214 #define MX51_ECSPI_CTRL_SMC (1 << 3)
215 #define MX51_ECSPI_CTRL_MODE_MASK (0xf << 4)
216 #define MX51_ECSPI_CTRL_POSTDIV_OFFSET 8
217 #define MX51_ECSPI_CTRL_PREDIV_OFFSET 12
218 #define MX51_ECSPI_CTRL_CS(cs) ((cs) << 18)
219 #define MX51_ECSPI_CTRL_BL_OFFSET 20
221 #define MX51_ECSPI_CONFIG 0x0c
222 #define MX51_ECSPI_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0))
223 #define MX51_ECSPI_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4))
224 #define MX51_ECSPI_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8))
225 #define MX51_ECSPI_CONFIG_SSBPOL(cs) (1 << ((cs) + 12))
226 #define MX51_ECSPI_CONFIG_SCLKCTL(cs) (1 << ((cs) + 20))
228 #define MX51_ECSPI_INT 0x10
229 #define MX51_ECSPI_INT_TEEN (1 << 0)
230 #define MX51_ECSPI_INT_RREN (1 << 3)
232 #define MX51_ECSPI_DMA 0x14
233 #define MX51_ECSPI_DMA_TX_WML_OFFSET 0
234 #define MX51_ECSPI_DMA_TX_WML_MASK 0x3F
235 #define MX51_ECSPI_DMA_RX_WML_OFFSET 16
236 #define MX51_ECSPI_DMA_RX_WML_MASK (0x3F << 16)
237 #define MX51_ECSPI_DMA_RXT_WML_OFFSET 24
238 #define MX51_ECSPI_DMA_RXT_WML_MASK (0x3F << 24)
240 #define MX51_ECSPI_DMA_TEDEN_OFFSET 7
241 #define MX51_ECSPI_DMA_RXDEN_OFFSET 23
242 #define MX51_ECSPI_DMA_RXTDEN_OFFSET 31
244 #define MX51_ECSPI_STAT 0x18
245 #define MX51_ECSPI_STAT_RR (1 << 3)
247 /* MX51 eCSPI */
248 static unsigned int mx51_ecspi_clkdiv(unsigned int fin, unsigned int fspi,
249 unsigned int *fres)
252 * there are two 4-bit dividers, the pre-divider divides by
253 * $pre, the post-divider by 2^$post
255 unsigned int pre, post;
257 if (unlikely(fspi > fin))
258 return 0;
260 post = fls(fin) - fls(fspi);
261 if (fin > fspi << post)
262 post++;
264 /* now we have: (fin <= fspi << post) with post being minimal */
266 post = max(4U, post) - 4;
267 if (unlikely(post > 0xf)) {
268 pr_err("%s: cannot set clock freq: %u (base freq: %u)\n",
269 __func__, fspi, fin);
270 return 0xff;
273 pre = DIV_ROUND_UP(fin, fspi << post) - 1;
275 pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n",
276 __func__, fin, fspi, post, pre);
278 /* Resulting frequency for the SCLK line. */
279 *fres = (fin / (pre + 1)) >> post;
281 return (pre << MX51_ECSPI_CTRL_PREDIV_OFFSET) |
282 (post << MX51_ECSPI_CTRL_POSTDIV_OFFSET);
285 static void __maybe_unused mx51_ecspi_intctrl(struct spi_imx_data *spi_imx, int enable)
287 unsigned val = 0;
289 if (enable & MXC_INT_TE)
290 val |= MX51_ECSPI_INT_TEEN;
292 if (enable & MXC_INT_RR)
293 val |= MX51_ECSPI_INT_RREN;
295 writel(val, spi_imx->base + MX51_ECSPI_INT);
298 static void __maybe_unused mx51_ecspi_trigger(struct spi_imx_data *spi_imx)
300 u32 reg = readl(spi_imx->base + MX51_ECSPI_CTRL);
302 if (!spi_imx->usedma)
303 reg |= MX51_ECSPI_CTRL_XCH;
304 else if (!spi_imx->dma_finished)
305 reg |= MX51_ECSPI_CTRL_SMC;
306 else
307 reg &= ~MX51_ECSPI_CTRL_SMC;
308 writel(reg, spi_imx->base + MX51_ECSPI_CTRL);
311 static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
312 struct spi_imx_config *config)
314 u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0, dma = 0;
315 u32 tx_wml_cfg, rx_wml_cfg, rxt_wml_cfg;
316 u32 clk = config->speed_hz, delay;
319 * The hardware seems to have a race condition when changing modes. The
320 * current assumption is that the selection of the channel arrives
321 * earlier in the hardware than the mode bits when they are written at
322 * the same time.
323 * So set master mode for all channels as we do not support slave mode.
325 ctrl |= MX51_ECSPI_CTRL_MODE_MASK;
327 /* set clock speed */
328 ctrl |= mx51_ecspi_clkdiv(spi_imx->spi_clk, config->speed_hz, &clk);
330 /* set chip select to use */
331 ctrl |= MX51_ECSPI_CTRL_CS(config->cs);
333 ctrl |= (config->bpw - 1) << MX51_ECSPI_CTRL_BL_OFFSET;
335 cfg |= MX51_ECSPI_CONFIG_SBBCTRL(config->cs);
337 if (config->mode & SPI_CPHA)
338 cfg |= MX51_ECSPI_CONFIG_SCLKPHA(config->cs);
340 if (config->mode & SPI_CPOL) {
341 cfg |= MX51_ECSPI_CONFIG_SCLKPOL(config->cs);
342 cfg |= MX51_ECSPI_CONFIG_SCLKCTL(config->cs);
344 if (config->mode & SPI_CS_HIGH)
345 cfg |= MX51_ECSPI_CONFIG_SSBPOL(config->cs);
347 writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
348 writel(cfg, spi_imx->base + MX51_ECSPI_CONFIG);
351 * Wait until the changes in the configuration register CONFIGREG
352 * propagate into the hardware. It takes exactly one tick of the
353 * SCLK clock, but we will wait two SCLK clock just to be sure. The
354 * effect of the delay it takes for the hardware to apply changes
355 * is noticable if the SCLK clock run very slow. In such a case, if
356 * the polarity of SCLK should be inverted, the GPIO ChipSelect might
357 * be asserted before the SCLK polarity changes, which would disrupt
358 * the SPI communication as the device on the other end would consider
359 * the change of SCLK polarity as a clock tick already.
361 delay = (2 * 1000000) / clk;
362 if (likely(delay < 10)) /* SCLK is faster than 100 kHz */
363 udelay(delay);
364 else /* SCLK is _very_ slow */
365 usleep_range(delay, delay + 10);
368 * Configure the DMA register: setup the watermark
369 * and enable DMA request.
371 if (spi_imx->dma_is_inited) {
372 dma = readl(spi_imx->base + MX51_ECSPI_DMA);
374 spi_imx->rxt_wml = spi_imx_get_fifosize(spi_imx) / 2;
375 rx_wml_cfg = spi_imx->rx_wml << MX51_ECSPI_DMA_RX_WML_OFFSET;
376 tx_wml_cfg = spi_imx->tx_wml << MX51_ECSPI_DMA_TX_WML_OFFSET;
377 rxt_wml_cfg = spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET;
378 dma = (dma & ~MX51_ECSPI_DMA_TX_WML_MASK
379 & ~MX51_ECSPI_DMA_RX_WML_MASK
380 & ~MX51_ECSPI_DMA_RXT_WML_MASK)
381 | rx_wml_cfg | tx_wml_cfg | rxt_wml_cfg
382 |(1 << MX51_ECSPI_DMA_TEDEN_OFFSET)
383 |(1 << MX51_ECSPI_DMA_RXDEN_OFFSET)
384 |(1 << MX51_ECSPI_DMA_RXTDEN_OFFSET);
386 writel(dma, spi_imx->base + MX51_ECSPI_DMA);
389 return 0;
392 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
394 return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
397 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
399 /* drain receive buffer */
400 while (mx51_ecspi_rx_available(spi_imx))
401 readl(spi_imx->base + MXC_CSPIRXDATA);
404 #define MX31_INTREG_TEEN (1 << 0)
405 #define MX31_INTREG_RREN (1 << 3)
407 #define MX31_CSPICTRL_ENABLE (1 << 0)
408 #define MX31_CSPICTRL_MASTER (1 << 1)
409 #define MX31_CSPICTRL_XCH (1 << 2)
410 #define MX31_CSPICTRL_POL (1 << 4)
411 #define MX31_CSPICTRL_PHA (1 << 5)
412 #define MX31_CSPICTRL_SSCTL (1 << 6)
413 #define MX31_CSPICTRL_SSPOL (1 << 7)
414 #define MX31_CSPICTRL_BC_SHIFT 8
415 #define MX35_CSPICTRL_BL_SHIFT 20
416 #define MX31_CSPICTRL_CS_SHIFT 24
417 #define MX35_CSPICTRL_CS_SHIFT 12
418 #define MX31_CSPICTRL_DR_SHIFT 16
420 #define MX31_CSPISTATUS 0x14
421 #define MX31_STATUS_RR (1 << 3)
423 /* These functions also work for the i.MX35, but be aware that
424 * the i.MX35 has a slightly different register layout for bits
425 * we do not use here.
427 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
429 unsigned int val = 0;
431 if (enable & MXC_INT_TE)
432 val |= MX31_INTREG_TEEN;
433 if (enable & MXC_INT_RR)
434 val |= MX31_INTREG_RREN;
436 writel(val, spi_imx->base + MXC_CSPIINT);
439 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
441 unsigned int reg;
443 reg = readl(spi_imx->base + MXC_CSPICTRL);
444 reg |= MX31_CSPICTRL_XCH;
445 writel(reg, spi_imx->base + MXC_CSPICTRL);
448 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
449 struct spi_imx_config *config)
451 unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
452 int cs = spi_imx->chipselect[config->cs];
454 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
455 MX31_CSPICTRL_DR_SHIFT;
457 if (is_imx35_cspi(spi_imx)) {
458 reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
459 reg |= MX31_CSPICTRL_SSCTL;
460 } else {
461 reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
464 if (config->mode & SPI_CPHA)
465 reg |= MX31_CSPICTRL_PHA;
466 if (config->mode & SPI_CPOL)
467 reg |= MX31_CSPICTRL_POL;
468 if (config->mode & SPI_CS_HIGH)
469 reg |= MX31_CSPICTRL_SSPOL;
470 if (cs < 0)
471 reg |= (cs + 32) <<
472 (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
473 MX31_CSPICTRL_CS_SHIFT);
475 writel(reg, spi_imx->base + MXC_CSPICTRL);
477 return 0;
480 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
482 return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
485 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
487 /* drain receive buffer */
488 while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
489 readl(spi_imx->base + MXC_CSPIRXDATA);
492 #define MX21_INTREG_RR (1 << 4)
493 #define MX21_INTREG_TEEN (1 << 9)
494 #define MX21_INTREG_RREN (1 << 13)
496 #define MX21_CSPICTRL_POL (1 << 5)
497 #define MX21_CSPICTRL_PHA (1 << 6)
498 #define MX21_CSPICTRL_SSPOL (1 << 8)
499 #define MX21_CSPICTRL_XCH (1 << 9)
500 #define MX21_CSPICTRL_ENABLE (1 << 10)
501 #define MX21_CSPICTRL_MASTER (1 << 11)
502 #define MX21_CSPICTRL_DR_SHIFT 14
503 #define MX21_CSPICTRL_CS_SHIFT 19
505 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
507 unsigned int val = 0;
509 if (enable & MXC_INT_TE)
510 val |= MX21_INTREG_TEEN;
511 if (enable & MXC_INT_RR)
512 val |= MX21_INTREG_RREN;
514 writel(val, spi_imx->base + MXC_CSPIINT);
517 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
519 unsigned int reg;
521 reg = readl(spi_imx->base + MXC_CSPICTRL);
522 reg |= MX21_CSPICTRL_XCH;
523 writel(reg, spi_imx->base + MXC_CSPICTRL);
526 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
527 struct spi_imx_config *config)
529 unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
530 int cs = spi_imx->chipselect[config->cs];
531 unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
533 reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
534 MX21_CSPICTRL_DR_SHIFT;
535 reg |= config->bpw - 1;
537 if (config->mode & SPI_CPHA)
538 reg |= MX21_CSPICTRL_PHA;
539 if (config->mode & SPI_CPOL)
540 reg |= MX21_CSPICTRL_POL;
541 if (config->mode & SPI_CS_HIGH)
542 reg |= MX21_CSPICTRL_SSPOL;
543 if (cs < 0)
544 reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
546 writel(reg, spi_imx->base + MXC_CSPICTRL);
548 return 0;
551 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
553 return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
556 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
558 writel(1, spi_imx->base + MXC_RESET);
561 #define MX1_INTREG_RR (1 << 3)
562 #define MX1_INTREG_TEEN (1 << 8)
563 #define MX1_INTREG_RREN (1 << 11)
565 #define MX1_CSPICTRL_POL (1 << 4)
566 #define MX1_CSPICTRL_PHA (1 << 5)
567 #define MX1_CSPICTRL_XCH (1 << 8)
568 #define MX1_CSPICTRL_ENABLE (1 << 9)
569 #define MX1_CSPICTRL_MASTER (1 << 10)
570 #define MX1_CSPICTRL_DR_SHIFT 13
572 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
574 unsigned int val = 0;
576 if (enable & MXC_INT_TE)
577 val |= MX1_INTREG_TEEN;
578 if (enable & MXC_INT_RR)
579 val |= MX1_INTREG_RREN;
581 writel(val, spi_imx->base + MXC_CSPIINT);
584 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
586 unsigned int reg;
588 reg = readl(spi_imx->base + MXC_CSPICTRL);
589 reg |= MX1_CSPICTRL_XCH;
590 writel(reg, spi_imx->base + MXC_CSPICTRL);
593 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
594 struct spi_imx_config *config)
596 unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
598 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
599 MX1_CSPICTRL_DR_SHIFT;
600 reg |= config->bpw - 1;
602 if (config->mode & SPI_CPHA)
603 reg |= MX1_CSPICTRL_PHA;
604 if (config->mode & SPI_CPOL)
605 reg |= MX1_CSPICTRL_POL;
607 writel(reg, spi_imx->base + MXC_CSPICTRL);
609 return 0;
612 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
614 return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
617 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
619 writel(1, spi_imx->base + MXC_RESET);
622 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
623 .intctrl = mx1_intctrl,
624 .config = mx1_config,
625 .trigger = mx1_trigger,
626 .rx_available = mx1_rx_available,
627 .reset = mx1_reset,
628 .devtype = IMX1_CSPI,
631 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
632 .intctrl = mx21_intctrl,
633 .config = mx21_config,
634 .trigger = mx21_trigger,
635 .rx_available = mx21_rx_available,
636 .reset = mx21_reset,
637 .devtype = IMX21_CSPI,
640 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
641 /* i.mx27 cspi shares the functions with i.mx21 one */
642 .intctrl = mx21_intctrl,
643 .config = mx21_config,
644 .trigger = mx21_trigger,
645 .rx_available = mx21_rx_available,
646 .reset = mx21_reset,
647 .devtype = IMX27_CSPI,
650 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
651 .intctrl = mx31_intctrl,
652 .config = mx31_config,
653 .trigger = mx31_trigger,
654 .rx_available = mx31_rx_available,
655 .reset = mx31_reset,
656 .devtype = IMX31_CSPI,
659 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
660 /* i.mx35 and later cspi shares the functions with i.mx31 one */
661 .intctrl = mx31_intctrl,
662 .config = mx31_config,
663 .trigger = mx31_trigger,
664 .rx_available = mx31_rx_available,
665 .reset = mx31_reset,
666 .devtype = IMX35_CSPI,
669 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
670 .intctrl = mx51_ecspi_intctrl,
671 .config = mx51_ecspi_config,
672 .trigger = mx51_ecspi_trigger,
673 .rx_available = mx51_ecspi_rx_available,
674 .reset = mx51_ecspi_reset,
675 .devtype = IMX51_ECSPI,
678 static const struct platform_device_id spi_imx_devtype[] = {
680 .name = "imx1-cspi",
681 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
682 }, {
683 .name = "imx21-cspi",
684 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
685 }, {
686 .name = "imx27-cspi",
687 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
688 }, {
689 .name = "imx31-cspi",
690 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
691 }, {
692 .name = "imx35-cspi",
693 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
694 }, {
695 .name = "imx51-ecspi",
696 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
697 }, {
698 /* sentinel */
702 static const struct of_device_id spi_imx_dt_ids[] = {
703 { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
704 { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
705 { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
706 { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
707 { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
708 { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
709 { /* sentinel */ }
711 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
713 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
715 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
716 int gpio = spi_imx->chipselect[spi->chip_select];
717 int active = is_active != BITBANG_CS_INACTIVE;
718 int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
720 if (!gpio_is_valid(gpio))
721 return;
723 gpio_set_value(gpio, dev_is_lowactive ^ active);
726 static void spi_imx_push(struct spi_imx_data *spi_imx)
728 while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
729 if (!spi_imx->count)
730 break;
731 spi_imx->tx(spi_imx);
732 spi_imx->txfifo++;
735 spi_imx->devtype_data->trigger(spi_imx);
738 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
740 struct spi_imx_data *spi_imx = dev_id;
742 while (spi_imx->devtype_data->rx_available(spi_imx)) {
743 spi_imx->rx(spi_imx);
744 spi_imx->txfifo--;
747 if (spi_imx->count) {
748 spi_imx_push(spi_imx);
749 return IRQ_HANDLED;
752 if (spi_imx->txfifo) {
753 /* No data left to push, but still waiting for rx data,
754 * enable receive data available interrupt.
756 spi_imx->devtype_data->intctrl(
757 spi_imx, MXC_INT_RR);
758 return IRQ_HANDLED;
761 spi_imx->devtype_data->intctrl(spi_imx, 0);
762 complete(&spi_imx->xfer_done);
764 return IRQ_HANDLED;
767 static int spi_imx_setupxfer(struct spi_device *spi,
768 struct spi_transfer *t)
770 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
771 struct spi_imx_config config;
773 config.bpw = t ? t->bits_per_word : spi->bits_per_word;
774 config.speed_hz = t ? t->speed_hz : spi->max_speed_hz;
775 config.mode = spi->mode;
776 config.cs = spi->chip_select;
778 if (!config.speed_hz)
779 config.speed_hz = spi->max_speed_hz;
780 if (!config.bpw)
781 config.bpw = spi->bits_per_word;
783 /* Initialize the functions for transfer */
784 if (config.bpw <= 8) {
785 spi_imx->rx = spi_imx_buf_rx_u8;
786 spi_imx->tx = spi_imx_buf_tx_u8;
787 } else if (config.bpw <= 16) {
788 spi_imx->rx = spi_imx_buf_rx_u16;
789 spi_imx->tx = spi_imx_buf_tx_u16;
790 } else {
791 spi_imx->rx = spi_imx_buf_rx_u32;
792 spi_imx->tx = spi_imx_buf_tx_u32;
795 spi_imx->devtype_data->config(spi_imx, &config);
797 return 0;
800 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
802 struct spi_master *master = spi_imx->bitbang.master;
804 if (master->dma_rx) {
805 dma_release_channel(master->dma_rx);
806 master->dma_rx = NULL;
809 if (master->dma_tx) {
810 dma_release_channel(master->dma_tx);
811 master->dma_tx = NULL;
814 spi_imx->dma_is_inited = 0;
817 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
818 struct spi_master *master,
819 const struct resource *res)
821 struct dma_slave_config slave_config = {};
822 int ret;
824 /* use pio mode for i.mx6dl chip TKT238285 */
825 if (of_machine_is_compatible("fsl,imx6dl"))
826 return 0;
828 /* Prepare for TX DMA: */
829 master->dma_tx = dma_request_slave_channel(dev, "tx");
830 if (!master->dma_tx) {
831 dev_err(dev, "cannot get the TX DMA channel!\n");
832 ret = -EINVAL;
833 goto err;
836 slave_config.direction = DMA_MEM_TO_DEV;
837 slave_config.dst_addr = res->start + MXC_CSPITXDATA;
838 slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
839 slave_config.dst_maxburst = spi_imx_get_fifosize(spi_imx) / 2;
840 ret = dmaengine_slave_config(master->dma_tx, &slave_config);
841 if (ret) {
842 dev_err(dev, "error in TX dma configuration.\n");
843 goto err;
846 /* Prepare for RX : */
847 master->dma_rx = dma_request_slave_channel(dev, "rx");
848 if (!master->dma_rx) {
849 dev_dbg(dev, "cannot get the DMA channel.\n");
850 ret = -EINVAL;
851 goto err;
854 slave_config.direction = DMA_DEV_TO_MEM;
855 slave_config.src_addr = res->start + MXC_CSPIRXDATA;
856 slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
857 slave_config.src_maxburst = spi_imx_get_fifosize(spi_imx) / 2;
858 ret = dmaengine_slave_config(master->dma_rx, &slave_config);
859 if (ret) {
860 dev_err(dev, "error in RX dma configuration.\n");
861 goto err;
864 init_completion(&spi_imx->dma_rx_completion);
865 init_completion(&spi_imx->dma_tx_completion);
866 master->can_dma = spi_imx_can_dma;
867 master->max_dma_len = MAX_SDMA_BD_BYTES;
868 spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
869 SPI_MASTER_MUST_TX;
870 spi_imx->tx_wml = spi_imx_get_fifosize(spi_imx) / 2;
871 spi_imx->rx_wml = spi_imx_get_fifosize(spi_imx) / 2;
872 spi_imx->dma_is_inited = 1;
874 return 0;
875 err:
876 spi_imx_sdma_exit(spi_imx);
877 return ret;
880 static void spi_imx_dma_rx_callback(void *cookie)
882 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
884 complete(&spi_imx->dma_rx_completion);
887 static void spi_imx_dma_tx_callback(void *cookie)
889 struct spi_imx_data *spi_imx = (struct spi_imx_data *)cookie;
891 complete(&spi_imx->dma_tx_completion);
894 static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
895 struct spi_transfer *transfer)
897 struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
898 int ret;
899 unsigned long timeout;
900 u32 dma;
901 int left;
902 struct spi_master *master = spi_imx->bitbang.master;
903 struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
905 if (tx) {
906 desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
907 tx->sgl, tx->nents, DMA_MEM_TO_DEV,
908 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
909 if (!desc_tx)
910 goto no_dma;
912 desc_tx->callback = spi_imx_dma_tx_callback;
913 desc_tx->callback_param = (void *)spi_imx;
914 dmaengine_submit(desc_tx);
917 if (rx) {
918 desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
919 rx->sgl, rx->nents, DMA_DEV_TO_MEM,
920 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
921 if (!desc_rx)
922 goto no_dma;
924 desc_rx->callback = spi_imx_dma_rx_callback;
925 desc_rx->callback_param = (void *)spi_imx;
926 dmaengine_submit(desc_rx);
929 reinit_completion(&spi_imx->dma_rx_completion);
930 reinit_completion(&spi_imx->dma_tx_completion);
932 /* Trigger the cspi module. */
933 spi_imx->dma_finished = 0;
935 dma = readl(spi_imx->base + MX51_ECSPI_DMA);
936 dma = dma & (~MX51_ECSPI_DMA_RXT_WML_MASK);
937 /* Change RX_DMA_LENGTH trigger dma fetch tail data */
938 left = transfer->len % spi_imx->rxt_wml;
939 if (left)
940 writel(dma | (left << MX51_ECSPI_DMA_RXT_WML_OFFSET),
941 spi_imx->base + MX51_ECSPI_DMA);
942 spi_imx->devtype_data->trigger(spi_imx);
944 dma_async_issue_pending(master->dma_tx);
945 dma_async_issue_pending(master->dma_rx);
946 /* Wait SDMA to finish the data transfer.*/
947 timeout = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
948 IMX_DMA_TIMEOUT);
949 if (!timeout) {
950 pr_warn("%s %s: I/O Error in DMA TX\n",
951 dev_driver_string(&master->dev),
952 dev_name(&master->dev));
953 dmaengine_terminate_all(master->dma_tx);
954 } else {
955 timeout = wait_for_completion_timeout(
956 &spi_imx->dma_rx_completion, IMX_DMA_TIMEOUT);
957 if (!timeout) {
958 pr_warn("%s %s: I/O Error in DMA RX\n",
959 dev_driver_string(&master->dev),
960 dev_name(&master->dev));
961 spi_imx->devtype_data->reset(spi_imx);
962 dmaengine_terminate_all(master->dma_rx);
964 writel(dma |
965 spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET,
966 spi_imx->base + MX51_ECSPI_DMA);
969 spi_imx->dma_finished = 1;
970 spi_imx->devtype_data->trigger(spi_imx);
972 if (!timeout)
973 ret = -ETIMEDOUT;
974 else
975 ret = transfer->len;
977 return ret;
979 no_dma:
980 pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
981 dev_driver_string(&master->dev),
982 dev_name(&master->dev));
983 return -EAGAIN;
986 static int spi_imx_pio_transfer(struct spi_device *spi,
987 struct spi_transfer *transfer)
989 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
991 spi_imx->tx_buf = transfer->tx_buf;
992 spi_imx->rx_buf = transfer->rx_buf;
993 spi_imx->count = transfer->len;
994 spi_imx->txfifo = 0;
996 reinit_completion(&spi_imx->xfer_done);
998 spi_imx_push(spi_imx);
1000 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1002 wait_for_completion(&spi_imx->xfer_done);
1004 return transfer->len;
1007 static int spi_imx_transfer(struct spi_device *spi,
1008 struct spi_transfer *transfer)
1010 int ret;
1011 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1013 if (spi_imx->bitbang.master->can_dma &&
1014 spi_imx_can_dma(spi_imx->bitbang.master, spi, transfer)) {
1015 spi_imx->usedma = true;
1016 ret = spi_imx_dma_transfer(spi_imx, transfer);
1017 if (ret != -EAGAIN)
1018 return ret;
1020 spi_imx->usedma = false;
1022 return spi_imx_pio_transfer(spi, transfer);
1025 static int spi_imx_setup(struct spi_device *spi)
1027 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1028 int gpio = spi_imx->chipselect[spi->chip_select];
1030 dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1031 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1033 if (gpio_is_valid(gpio))
1034 gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
1036 spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1038 return 0;
1041 static void spi_imx_cleanup(struct spi_device *spi)
1045 static int
1046 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1048 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1049 int ret;
1051 ret = clk_enable(spi_imx->clk_per);
1052 if (ret)
1053 return ret;
1055 ret = clk_enable(spi_imx->clk_ipg);
1056 if (ret) {
1057 clk_disable(spi_imx->clk_per);
1058 return ret;
1061 return 0;
1064 static int
1065 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1067 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1069 clk_disable(spi_imx->clk_ipg);
1070 clk_disable(spi_imx->clk_per);
1071 return 0;
1074 static int spi_imx_probe(struct platform_device *pdev)
1076 struct device_node *np = pdev->dev.of_node;
1077 const struct of_device_id *of_id =
1078 of_match_device(spi_imx_dt_ids, &pdev->dev);
1079 struct spi_imx_master *mxc_platform_info =
1080 dev_get_platdata(&pdev->dev);
1081 struct spi_master *master;
1082 struct spi_imx_data *spi_imx;
1083 struct resource *res;
1084 int i, ret, num_cs, irq;
1086 if (!np && !mxc_platform_info) {
1087 dev_err(&pdev->dev, "can't get the platform data\n");
1088 return -EINVAL;
1091 ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
1092 if (ret < 0) {
1093 if (mxc_platform_info)
1094 num_cs = mxc_platform_info->num_chipselect;
1095 else
1096 return ret;
1099 master = spi_alloc_master(&pdev->dev,
1100 sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
1101 if (!master)
1102 return -ENOMEM;
1104 platform_set_drvdata(pdev, master);
1106 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1107 master->bus_num = pdev->id;
1108 master->num_chipselect = num_cs;
1110 spi_imx = spi_master_get_devdata(master);
1111 spi_imx->bitbang.master = master;
1113 for (i = 0; i < master->num_chipselect; i++) {
1114 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
1115 if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
1116 cs_gpio = mxc_platform_info->chipselect[i];
1118 spi_imx->chipselect[i] = cs_gpio;
1119 if (!gpio_is_valid(cs_gpio))
1120 continue;
1122 ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
1123 DRIVER_NAME);
1124 if (ret) {
1125 dev_err(&pdev->dev, "can't get cs gpios\n");
1126 goto out_master_put;
1130 spi_imx->bitbang.chipselect = spi_imx_chipselect;
1131 spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1132 spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1133 spi_imx->bitbang.master->setup = spi_imx_setup;
1134 spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1135 spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1136 spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1137 spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1139 init_completion(&spi_imx->xfer_done);
1141 spi_imx->devtype_data = of_id ? of_id->data :
1142 (struct spi_imx_devtype_data *) pdev->id_entry->driver_data;
1144 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1145 spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1146 if (IS_ERR(spi_imx->base)) {
1147 ret = PTR_ERR(spi_imx->base);
1148 goto out_master_put;
1151 irq = platform_get_irq(pdev, 0);
1152 if (irq < 0) {
1153 ret = irq;
1154 goto out_master_put;
1157 ret = devm_request_irq(&pdev->dev, irq, spi_imx_isr, 0,
1158 dev_name(&pdev->dev), spi_imx);
1159 if (ret) {
1160 dev_err(&pdev->dev, "can't get irq%d: %d\n", irq, ret);
1161 goto out_master_put;
1164 spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1165 if (IS_ERR(spi_imx->clk_ipg)) {
1166 ret = PTR_ERR(spi_imx->clk_ipg);
1167 goto out_master_put;
1170 spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1171 if (IS_ERR(spi_imx->clk_per)) {
1172 ret = PTR_ERR(spi_imx->clk_per);
1173 goto out_master_put;
1176 ret = clk_prepare_enable(spi_imx->clk_per);
1177 if (ret)
1178 goto out_master_put;
1180 ret = clk_prepare_enable(spi_imx->clk_ipg);
1181 if (ret)
1182 goto out_put_per;
1184 spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1186 * Only validated on i.mx6 now, can remove the constrain if validated on
1187 * other chips.
1189 if (spi_imx->devtype_data == &imx51_ecspi_devtype_data
1190 && spi_imx_sdma_init(&pdev->dev, spi_imx, master, res))
1191 dev_err(&pdev->dev, "dma setup error,use pio instead\n");
1193 spi_imx->devtype_data->reset(spi_imx);
1195 spi_imx->devtype_data->intctrl(spi_imx, 0);
1197 master->dev.of_node = pdev->dev.of_node;
1198 ret = spi_bitbang_start(&spi_imx->bitbang);
1199 if (ret) {
1200 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1201 goto out_clk_put;
1204 dev_info(&pdev->dev, "probed\n");
1206 clk_disable(spi_imx->clk_ipg);
1207 clk_disable(spi_imx->clk_per);
1208 return ret;
1210 out_clk_put:
1211 clk_disable_unprepare(spi_imx->clk_ipg);
1212 out_put_per:
1213 clk_disable_unprepare(spi_imx->clk_per);
1214 out_master_put:
1215 spi_master_put(master);
1217 return ret;
1220 static int spi_imx_remove(struct platform_device *pdev)
1222 struct spi_master *master = platform_get_drvdata(pdev);
1223 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1225 spi_bitbang_stop(&spi_imx->bitbang);
1227 writel(0, spi_imx->base + MXC_CSPICTRL);
1228 clk_unprepare(spi_imx->clk_ipg);
1229 clk_unprepare(spi_imx->clk_per);
1230 spi_imx_sdma_exit(spi_imx);
1231 spi_master_put(master);
1233 return 0;
1236 static struct platform_driver spi_imx_driver = {
1237 .driver = {
1238 .name = DRIVER_NAME,
1239 .of_match_table = spi_imx_dt_ids,
1241 .id_table = spi_imx_devtype,
1242 .probe = spi_imx_probe,
1243 .remove = spi_imx_remove,
1245 module_platform_driver(spi_imx_driver);
1247 MODULE_DESCRIPTION("SPI Master Controller driver");
1248 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1249 MODULE_LICENSE("GPL");
1250 MODULE_ALIAS("platform:" DRIVER_NAME);