Input: synaptics - log queried and quirked dimension values
[linux-2.6/btrfs-unstable.git] / drivers / spi / spi-imx.c
blobfe1b7699fab634a31ae9e903146b775c467ddd80
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 int irq;
93 struct clk *clk_per;
94 struct clk *clk_ipg;
95 unsigned long spi_clk;
97 unsigned int count;
98 void (*tx)(struct spi_imx_data *);
99 void (*rx)(struct spi_imx_data *);
100 void *rx_buf;
101 const void *tx_buf;
102 unsigned int txfifo; /* number of words pushed in tx FIFO */
104 /* DMA */
105 unsigned int dma_is_inited;
106 unsigned int dma_finished;
107 bool usedma;
108 u32 rx_wml;
109 u32 tx_wml;
110 u32 rxt_wml;
111 struct completion dma_rx_completion;
112 struct completion dma_tx_completion;
114 const struct spi_imx_devtype_data *devtype_data;
115 int chipselect[0];
118 static inline int is_imx27_cspi(struct spi_imx_data *d)
120 return d->devtype_data->devtype == IMX27_CSPI;
123 static inline int is_imx35_cspi(struct spi_imx_data *d)
125 return d->devtype_data->devtype == IMX35_CSPI;
128 static inline unsigned spi_imx_get_fifosize(struct spi_imx_data *d)
130 return (d->devtype_data->devtype == IMX51_ECSPI) ? 64 : 8;
133 #define MXC_SPI_BUF_RX(type) \
134 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
136 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
138 if (spi_imx->rx_buf) { \
139 *(type *)spi_imx->rx_buf = val; \
140 spi_imx->rx_buf += sizeof(type); \
144 #define MXC_SPI_BUF_TX(type) \
145 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
147 type val = 0; \
149 if (spi_imx->tx_buf) { \
150 val = *(type *)spi_imx->tx_buf; \
151 spi_imx->tx_buf += sizeof(type); \
154 spi_imx->count -= sizeof(type); \
156 writel(val, spi_imx->base + MXC_CSPITXDATA); \
159 MXC_SPI_BUF_RX(u8)
160 MXC_SPI_BUF_TX(u8)
161 MXC_SPI_BUF_RX(u16)
162 MXC_SPI_BUF_TX(u16)
163 MXC_SPI_BUF_RX(u32)
164 MXC_SPI_BUF_TX(u32)
166 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
167 * (which is currently not the case in this driver)
169 static int mxc_clkdivs[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
170 256, 384, 512, 768, 1024};
172 /* MX21, MX27 */
173 static unsigned int spi_imx_clkdiv_1(unsigned int fin,
174 unsigned int fspi, unsigned int max)
176 int i;
178 for (i = 2; i < max; i++)
179 if (fspi * mxc_clkdivs[i] >= fin)
180 return i;
182 return max;
185 /* MX1, MX31, MX35, MX51 CSPI */
186 static unsigned int spi_imx_clkdiv_2(unsigned int fin,
187 unsigned int fspi)
189 int i, div = 4;
191 for (i = 0; i < 7; i++) {
192 if (fspi * div >= fin)
193 return i;
194 div <<= 1;
197 return 7;
200 static bool spi_imx_can_dma(struct spi_master *master, struct spi_device *spi,
201 struct spi_transfer *transfer)
203 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
205 if (spi_imx->dma_is_inited && (transfer->len > spi_imx->rx_wml)
206 && (transfer->len > spi_imx->tx_wml))
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->tx_wml = spi_imx_get_fifosize(spi_imx) / 2;
375 spi_imx->rx_wml = spi_imx_get_fifosize(spi_imx) / 2;
376 spi_imx->rxt_wml = spi_imx_get_fifosize(spi_imx) / 2;
377 rx_wml_cfg = spi_imx->rx_wml << MX51_ECSPI_DMA_RX_WML_OFFSET;
378 tx_wml_cfg = spi_imx->tx_wml << MX51_ECSPI_DMA_TX_WML_OFFSET;
379 rxt_wml_cfg = spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET;
380 dma = (dma & ~MX51_ECSPI_DMA_TX_WML_MASK
381 & ~MX51_ECSPI_DMA_RX_WML_MASK
382 & ~MX51_ECSPI_DMA_RXT_WML_MASK)
383 | rx_wml_cfg | tx_wml_cfg | rxt_wml_cfg
384 |(1 << MX51_ECSPI_DMA_TEDEN_OFFSET)
385 |(1 << MX51_ECSPI_DMA_RXDEN_OFFSET)
386 |(1 << MX51_ECSPI_DMA_RXTDEN_OFFSET);
388 writel(dma, spi_imx->base + MX51_ECSPI_DMA);
391 return 0;
394 static int __maybe_unused mx51_ecspi_rx_available(struct spi_imx_data *spi_imx)
396 return readl(spi_imx->base + MX51_ECSPI_STAT) & MX51_ECSPI_STAT_RR;
399 static void __maybe_unused mx51_ecspi_reset(struct spi_imx_data *spi_imx)
401 /* drain receive buffer */
402 while (mx51_ecspi_rx_available(spi_imx))
403 readl(spi_imx->base + MXC_CSPIRXDATA);
406 #define MX31_INTREG_TEEN (1 << 0)
407 #define MX31_INTREG_RREN (1 << 3)
409 #define MX31_CSPICTRL_ENABLE (1 << 0)
410 #define MX31_CSPICTRL_MASTER (1 << 1)
411 #define MX31_CSPICTRL_XCH (1 << 2)
412 #define MX31_CSPICTRL_POL (1 << 4)
413 #define MX31_CSPICTRL_PHA (1 << 5)
414 #define MX31_CSPICTRL_SSCTL (1 << 6)
415 #define MX31_CSPICTRL_SSPOL (1 << 7)
416 #define MX31_CSPICTRL_BC_SHIFT 8
417 #define MX35_CSPICTRL_BL_SHIFT 20
418 #define MX31_CSPICTRL_CS_SHIFT 24
419 #define MX35_CSPICTRL_CS_SHIFT 12
420 #define MX31_CSPICTRL_DR_SHIFT 16
422 #define MX31_CSPISTATUS 0x14
423 #define MX31_STATUS_RR (1 << 3)
425 /* These functions also work for the i.MX35, but be aware that
426 * the i.MX35 has a slightly different register layout for bits
427 * we do not use here.
429 static void __maybe_unused mx31_intctrl(struct spi_imx_data *spi_imx, int enable)
431 unsigned int val = 0;
433 if (enable & MXC_INT_TE)
434 val |= MX31_INTREG_TEEN;
435 if (enable & MXC_INT_RR)
436 val |= MX31_INTREG_RREN;
438 writel(val, spi_imx->base + MXC_CSPIINT);
441 static void __maybe_unused mx31_trigger(struct spi_imx_data *spi_imx)
443 unsigned int reg;
445 reg = readl(spi_imx->base + MXC_CSPICTRL);
446 reg |= MX31_CSPICTRL_XCH;
447 writel(reg, spi_imx->base + MXC_CSPICTRL);
450 static int __maybe_unused mx31_config(struct spi_imx_data *spi_imx,
451 struct spi_imx_config *config)
453 unsigned int reg = MX31_CSPICTRL_ENABLE | MX31_CSPICTRL_MASTER;
454 int cs = spi_imx->chipselect[config->cs];
456 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
457 MX31_CSPICTRL_DR_SHIFT;
459 if (is_imx35_cspi(spi_imx)) {
460 reg |= (config->bpw - 1) << MX35_CSPICTRL_BL_SHIFT;
461 reg |= MX31_CSPICTRL_SSCTL;
462 } else {
463 reg |= (config->bpw - 1) << MX31_CSPICTRL_BC_SHIFT;
466 if (config->mode & SPI_CPHA)
467 reg |= MX31_CSPICTRL_PHA;
468 if (config->mode & SPI_CPOL)
469 reg |= MX31_CSPICTRL_POL;
470 if (config->mode & SPI_CS_HIGH)
471 reg |= MX31_CSPICTRL_SSPOL;
472 if (cs < 0)
473 reg |= (cs + 32) <<
474 (is_imx35_cspi(spi_imx) ? MX35_CSPICTRL_CS_SHIFT :
475 MX31_CSPICTRL_CS_SHIFT);
477 writel(reg, spi_imx->base + MXC_CSPICTRL);
479 return 0;
482 static int __maybe_unused mx31_rx_available(struct spi_imx_data *spi_imx)
484 return readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR;
487 static void __maybe_unused mx31_reset(struct spi_imx_data *spi_imx)
489 /* drain receive buffer */
490 while (readl(spi_imx->base + MX31_CSPISTATUS) & MX31_STATUS_RR)
491 readl(spi_imx->base + MXC_CSPIRXDATA);
494 #define MX21_INTREG_RR (1 << 4)
495 #define MX21_INTREG_TEEN (1 << 9)
496 #define MX21_INTREG_RREN (1 << 13)
498 #define MX21_CSPICTRL_POL (1 << 5)
499 #define MX21_CSPICTRL_PHA (1 << 6)
500 #define MX21_CSPICTRL_SSPOL (1 << 8)
501 #define MX21_CSPICTRL_XCH (1 << 9)
502 #define MX21_CSPICTRL_ENABLE (1 << 10)
503 #define MX21_CSPICTRL_MASTER (1 << 11)
504 #define MX21_CSPICTRL_DR_SHIFT 14
505 #define MX21_CSPICTRL_CS_SHIFT 19
507 static void __maybe_unused mx21_intctrl(struct spi_imx_data *spi_imx, int enable)
509 unsigned int val = 0;
511 if (enable & MXC_INT_TE)
512 val |= MX21_INTREG_TEEN;
513 if (enable & MXC_INT_RR)
514 val |= MX21_INTREG_RREN;
516 writel(val, spi_imx->base + MXC_CSPIINT);
519 static void __maybe_unused mx21_trigger(struct spi_imx_data *spi_imx)
521 unsigned int reg;
523 reg = readl(spi_imx->base + MXC_CSPICTRL);
524 reg |= MX21_CSPICTRL_XCH;
525 writel(reg, spi_imx->base + MXC_CSPICTRL);
528 static int __maybe_unused mx21_config(struct spi_imx_data *spi_imx,
529 struct spi_imx_config *config)
531 unsigned int reg = MX21_CSPICTRL_ENABLE | MX21_CSPICTRL_MASTER;
532 int cs = spi_imx->chipselect[config->cs];
533 unsigned int max = is_imx27_cspi(spi_imx) ? 16 : 18;
535 reg |= spi_imx_clkdiv_1(spi_imx->spi_clk, config->speed_hz, max) <<
536 MX21_CSPICTRL_DR_SHIFT;
537 reg |= config->bpw - 1;
539 if (config->mode & SPI_CPHA)
540 reg |= MX21_CSPICTRL_PHA;
541 if (config->mode & SPI_CPOL)
542 reg |= MX21_CSPICTRL_POL;
543 if (config->mode & SPI_CS_HIGH)
544 reg |= MX21_CSPICTRL_SSPOL;
545 if (cs < 0)
546 reg |= (cs + 32) << MX21_CSPICTRL_CS_SHIFT;
548 writel(reg, spi_imx->base + MXC_CSPICTRL);
550 return 0;
553 static int __maybe_unused mx21_rx_available(struct spi_imx_data *spi_imx)
555 return readl(spi_imx->base + MXC_CSPIINT) & MX21_INTREG_RR;
558 static void __maybe_unused mx21_reset(struct spi_imx_data *spi_imx)
560 writel(1, spi_imx->base + MXC_RESET);
563 #define MX1_INTREG_RR (1 << 3)
564 #define MX1_INTREG_TEEN (1 << 8)
565 #define MX1_INTREG_RREN (1 << 11)
567 #define MX1_CSPICTRL_POL (1 << 4)
568 #define MX1_CSPICTRL_PHA (1 << 5)
569 #define MX1_CSPICTRL_XCH (1 << 8)
570 #define MX1_CSPICTRL_ENABLE (1 << 9)
571 #define MX1_CSPICTRL_MASTER (1 << 10)
572 #define MX1_CSPICTRL_DR_SHIFT 13
574 static void __maybe_unused mx1_intctrl(struct spi_imx_data *spi_imx, int enable)
576 unsigned int val = 0;
578 if (enable & MXC_INT_TE)
579 val |= MX1_INTREG_TEEN;
580 if (enable & MXC_INT_RR)
581 val |= MX1_INTREG_RREN;
583 writel(val, spi_imx->base + MXC_CSPIINT);
586 static void __maybe_unused mx1_trigger(struct spi_imx_data *spi_imx)
588 unsigned int reg;
590 reg = readl(spi_imx->base + MXC_CSPICTRL);
591 reg |= MX1_CSPICTRL_XCH;
592 writel(reg, spi_imx->base + MXC_CSPICTRL);
595 static int __maybe_unused mx1_config(struct spi_imx_data *spi_imx,
596 struct spi_imx_config *config)
598 unsigned int reg = MX1_CSPICTRL_ENABLE | MX1_CSPICTRL_MASTER;
600 reg |= spi_imx_clkdiv_2(spi_imx->spi_clk, config->speed_hz) <<
601 MX1_CSPICTRL_DR_SHIFT;
602 reg |= config->bpw - 1;
604 if (config->mode & SPI_CPHA)
605 reg |= MX1_CSPICTRL_PHA;
606 if (config->mode & SPI_CPOL)
607 reg |= MX1_CSPICTRL_POL;
609 writel(reg, spi_imx->base + MXC_CSPICTRL);
611 return 0;
614 static int __maybe_unused mx1_rx_available(struct spi_imx_data *spi_imx)
616 return readl(spi_imx->base + MXC_CSPIINT) & MX1_INTREG_RR;
619 static void __maybe_unused mx1_reset(struct spi_imx_data *spi_imx)
621 writel(1, spi_imx->base + MXC_RESET);
624 static struct spi_imx_devtype_data imx1_cspi_devtype_data = {
625 .intctrl = mx1_intctrl,
626 .config = mx1_config,
627 .trigger = mx1_trigger,
628 .rx_available = mx1_rx_available,
629 .reset = mx1_reset,
630 .devtype = IMX1_CSPI,
633 static struct spi_imx_devtype_data imx21_cspi_devtype_data = {
634 .intctrl = mx21_intctrl,
635 .config = mx21_config,
636 .trigger = mx21_trigger,
637 .rx_available = mx21_rx_available,
638 .reset = mx21_reset,
639 .devtype = IMX21_CSPI,
642 static struct spi_imx_devtype_data imx27_cspi_devtype_data = {
643 /* i.mx27 cspi shares the functions with i.mx21 one */
644 .intctrl = mx21_intctrl,
645 .config = mx21_config,
646 .trigger = mx21_trigger,
647 .rx_available = mx21_rx_available,
648 .reset = mx21_reset,
649 .devtype = IMX27_CSPI,
652 static struct spi_imx_devtype_data imx31_cspi_devtype_data = {
653 .intctrl = mx31_intctrl,
654 .config = mx31_config,
655 .trigger = mx31_trigger,
656 .rx_available = mx31_rx_available,
657 .reset = mx31_reset,
658 .devtype = IMX31_CSPI,
661 static struct spi_imx_devtype_data imx35_cspi_devtype_data = {
662 /* i.mx35 and later cspi shares the functions with i.mx31 one */
663 .intctrl = mx31_intctrl,
664 .config = mx31_config,
665 .trigger = mx31_trigger,
666 .rx_available = mx31_rx_available,
667 .reset = mx31_reset,
668 .devtype = IMX35_CSPI,
671 static struct spi_imx_devtype_data imx51_ecspi_devtype_data = {
672 .intctrl = mx51_ecspi_intctrl,
673 .config = mx51_ecspi_config,
674 .trigger = mx51_ecspi_trigger,
675 .rx_available = mx51_ecspi_rx_available,
676 .reset = mx51_ecspi_reset,
677 .devtype = IMX51_ECSPI,
680 static struct platform_device_id spi_imx_devtype[] = {
682 .name = "imx1-cspi",
683 .driver_data = (kernel_ulong_t) &imx1_cspi_devtype_data,
684 }, {
685 .name = "imx21-cspi",
686 .driver_data = (kernel_ulong_t) &imx21_cspi_devtype_data,
687 }, {
688 .name = "imx27-cspi",
689 .driver_data = (kernel_ulong_t) &imx27_cspi_devtype_data,
690 }, {
691 .name = "imx31-cspi",
692 .driver_data = (kernel_ulong_t) &imx31_cspi_devtype_data,
693 }, {
694 .name = "imx35-cspi",
695 .driver_data = (kernel_ulong_t) &imx35_cspi_devtype_data,
696 }, {
697 .name = "imx51-ecspi",
698 .driver_data = (kernel_ulong_t) &imx51_ecspi_devtype_data,
699 }, {
700 /* sentinel */
704 static const struct of_device_id spi_imx_dt_ids[] = {
705 { .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
706 { .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data, },
707 { .compatible = "fsl,imx27-cspi", .data = &imx27_cspi_devtype_data, },
708 { .compatible = "fsl,imx31-cspi", .data = &imx31_cspi_devtype_data, },
709 { .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
710 { .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
711 { /* sentinel */ }
713 MODULE_DEVICE_TABLE(of, spi_imx_dt_ids);
715 static void spi_imx_chipselect(struct spi_device *spi, int is_active)
717 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
718 int gpio = spi_imx->chipselect[spi->chip_select];
719 int active = is_active != BITBANG_CS_INACTIVE;
720 int dev_is_lowactive = !(spi->mode & SPI_CS_HIGH);
722 if (!gpio_is_valid(gpio))
723 return;
725 gpio_set_value(gpio, dev_is_lowactive ^ active);
728 static void spi_imx_push(struct spi_imx_data *spi_imx)
730 while (spi_imx->txfifo < spi_imx_get_fifosize(spi_imx)) {
731 if (!spi_imx->count)
732 break;
733 spi_imx->tx(spi_imx);
734 spi_imx->txfifo++;
737 spi_imx->devtype_data->trigger(spi_imx);
740 static irqreturn_t spi_imx_isr(int irq, void *dev_id)
742 struct spi_imx_data *spi_imx = dev_id;
744 while (spi_imx->devtype_data->rx_available(spi_imx)) {
745 spi_imx->rx(spi_imx);
746 spi_imx->txfifo--;
749 if (spi_imx->count) {
750 spi_imx_push(spi_imx);
751 return IRQ_HANDLED;
754 if (spi_imx->txfifo) {
755 /* No data left to push, but still waiting for rx data,
756 * enable receive data available interrupt.
758 spi_imx->devtype_data->intctrl(
759 spi_imx, MXC_INT_RR);
760 return IRQ_HANDLED;
763 spi_imx->devtype_data->intctrl(spi_imx, 0);
764 complete(&spi_imx->xfer_done);
766 return IRQ_HANDLED;
769 static int spi_imx_setupxfer(struct spi_device *spi,
770 struct spi_transfer *t)
772 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
773 struct spi_imx_config config;
775 config.bpw = t ? t->bits_per_word : spi->bits_per_word;
776 config.speed_hz = t ? t->speed_hz : spi->max_speed_hz;
777 config.mode = spi->mode;
778 config.cs = spi->chip_select;
780 if (!config.speed_hz)
781 config.speed_hz = spi->max_speed_hz;
782 if (!config.bpw)
783 config.bpw = spi->bits_per_word;
785 /* Initialize the functions for transfer */
786 if (config.bpw <= 8) {
787 spi_imx->rx = spi_imx_buf_rx_u8;
788 spi_imx->tx = spi_imx_buf_tx_u8;
789 } else if (config.bpw <= 16) {
790 spi_imx->rx = spi_imx_buf_rx_u16;
791 spi_imx->tx = spi_imx_buf_tx_u16;
792 } else {
793 spi_imx->rx = spi_imx_buf_rx_u32;
794 spi_imx->tx = spi_imx_buf_tx_u32;
797 spi_imx->devtype_data->config(spi_imx, &config);
799 return 0;
802 static void spi_imx_sdma_exit(struct spi_imx_data *spi_imx)
804 struct spi_master *master = spi_imx->bitbang.master;
806 if (master->dma_rx) {
807 dma_release_channel(master->dma_rx);
808 master->dma_rx = NULL;
811 if (master->dma_tx) {
812 dma_release_channel(master->dma_tx);
813 master->dma_tx = NULL;
816 spi_imx->dma_is_inited = 0;
819 static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
820 struct spi_master *master,
821 const struct resource *res)
823 struct dma_slave_config slave_config = {};
824 int ret;
826 /* use pio mode for i.mx6dl chip TKT238285 */
827 if (of_machine_is_compatible("fsl,imx6dl"))
828 return 0;
830 /* Prepare for TX DMA: */
831 master->dma_tx = dma_request_slave_channel(dev, "tx");
832 if (!master->dma_tx) {
833 dev_err(dev, "cannot get the TX DMA channel!\n");
834 ret = -EINVAL;
835 goto err;
838 slave_config.direction = DMA_MEM_TO_DEV;
839 slave_config.dst_addr = res->start + MXC_CSPITXDATA;
840 slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
841 slave_config.dst_maxburst = spi_imx_get_fifosize(spi_imx) / 2;
842 ret = dmaengine_slave_config(master->dma_tx, &slave_config);
843 if (ret) {
844 dev_err(dev, "error in TX dma configuration.\n");
845 goto err;
848 /* Prepare for RX : */
849 master->dma_rx = dma_request_slave_channel(dev, "rx");
850 if (!master->dma_rx) {
851 dev_dbg(dev, "cannot get the DMA channel.\n");
852 ret = -EINVAL;
853 goto err;
856 slave_config.direction = DMA_DEV_TO_MEM;
857 slave_config.src_addr = res->start + MXC_CSPIRXDATA;
858 slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
859 slave_config.src_maxburst = spi_imx_get_fifosize(spi_imx) / 2;
860 ret = dmaengine_slave_config(master->dma_rx, &slave_config);
861 if (ret) {
862 dev_err(dev, "error in RX dma configuration.\n");
863 goto err;
866 init_completion(&spi_imx->dma_rx_completion);
867 init_completion(&spi_imx->dma_tx_completion);
868 master->can_dma = spi_imx_can_dma;
869 master->max_dma_len = MAX_SDMA_BD_BYTES;
870 spi_imx->bitbang.master->flags = SPI_MASTER_MUST_RX |
871 SPI_MASTER_MUST_TX;
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 u32 dma;
900 int left;
901 struct spi_master *master = spi_imx->bitbang.master;
902 struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
904 if (tx) {
905 desc_tx = dmaengine_prep_slave_sg(master->dma_tx,
906 tx->sgl, tx->nents, DMA_TO_DEVICE,
907 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
908 if (!desc_tx)
909 goto no_dma;
911 desc_tx->callback = spi_imx_dma_tx_callback;
912 desc_tx->callback_param = (void *)spi_imx;
913 dmaengine_submit(desc_tx);
916 if (rx) {
917 desc_rx = dmaengine_prep_slave_sg(master->dma_rx,
918 rx->sgl, rx->nents, DMA_FROM_DEVICE,
919 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
920 if (!desc_rx)
921 goto no_dma;
923 desc_rx->callback = spi_imx_dma_rx_callback;
924 desc_rx->callback_param = (void *)spi_imx;
925 dmaengine_submit(desc_rx);
928 reinit_completion(&spi_imx->dma_rx_completion);
929 reinit_completion(&spi_imx->dma_tx_completion);
931 /* Trigger the cspi module. */
932 spi_imx->dma_finished = 0;
934 dma = readl(spi_imx->base + MX51_ECSPI_DMA);
935 dma = dma & (~MX51_ECSPI_DMA_RXT_WML_MASK);
936 /* Change RX_DMA_LENGTH trigger dma fetch tail data */
937 left = transfer->len % spi_imx->rxt_wml;
938 if (left)
939 writel(dma | (left << MX51_ECSPI_DMA_RXT_WML_OFFSET),
940 spi_imx->base + MX51_ECSPI_DMA);
941 spi_imx->devtype_data->trigger(spi_imx);
943 dma_async_issue_pending(master->dma_tx);
944 dma_async_issue_pending(master->dma_rx);
945 /* Wait SDMA to finish the data transfer.*/
946 ret = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
947 IMX_DMA_TIMEOUT);
948 if (!ret) {
949 pr_warn("%s %s: I/O Error in DMA TX\n",
950 dev_driver_string(&master->dev),
951 dev_name(&master->dev));
952 dmaengine_terminate_all(master->dma_tx);
953 } else {
954 ret = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
955 IMX_DMA_TIMEOUT);
956 if (!ret) {
957 pr_warn("%s %s: I/O Error in DMA RX\n",
958 dev_driver_string(&master->dev),
959 dev_name(&master->dev));
960 spi_imx->devtype_data->reset(spi_imx);
961 dmaengine_terminate_all(master->dma_rx);
963 writel(dma |
964 spi_imx->rxt_wml << MX51_ECSPI_DMA_RXT_WML_OFFSET,
965 spi_imx->base + MX51_ECSPI_DMA);
968 spi_imx->dma_finished = 1;
969 spi_imx->devtype_data->trigger(spi_imx);
971 if (!ret)
972 ret = -ETIMEDOUT;
973 else if (ret > 0)
974 ret = transfer->len;
976 return ret;
978 no_dma:
979 pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
980 dev_driver_string(&master->dev),
981 dev_name(&master->dev));
982 return -EAGAIN;
985 static int spi_imx_pio_transfer(struct spi_device *spi,
986 struct spi_transfer *transfer)
988 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
990 spi_imx->tx_buf = transfer->tx_buf;
991 spi_imx->rx_buf = transfer->rx_buf;
992 spi_imx->count = transfer->len;
993 spi_imx->txfifo = 0;
995 reinit_completion(&spi_imx->xfer_done);
997 spi_imx_push(spi_imx);
999 spi_imx->devtype_data->intctrl(spi_imx, MXC_INT_TE);
1001 wait_for_completion(&spi_imx->xfer_done);
1003 return transfer->len;
1006 static int spi_imx_transfer(struct spi_device *spi,
1007 struct spi_transfer *transfer)
1009 int ret;
1010 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1012 if (spi_imx->bitbang.master->can_dma &&
1013 spi_imx_can_dma(spi_imx->bitbang.master, spi, transfer)) {
1014 spi_imx->usedma = true;
1015 ret = spi_imx_dma_transfer(spi_imx, transfer);
1016 if (ret != -EAGAIN)
1017 return ret;
1019 spi_imx->usedma = false;
1021 return spi_imx_pio_transfer(spi, transfer);
1024 static int spi_imx_setup(struct spi_device *spi)
1026 struct spi_imx_data *spi_imx = spi_master_get_devdata(spi->master);
1027 int gpio = spi_imx->chipselect[spi->chip_select];
1029 dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n", __func__,
1030 spi->mode, spi->bits_per_word, spi->max_speed_hz);
1032 if (gpio_is_valid(gpio))
1033 gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH ? 0 : 1);
1035 spi_imx_chipselect(spi, BITBANG_CS_INACTIVE);
1037 return 0;
1040 static void spi_imx_cleanup(struct spi_device *spi)
1044 static int
1045 spi_imx_prepare_message(struct spi_master *master, struct spi_message *msg)
1047 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1048 int ret;
1050 ret = clk_enable(spi_imx->clk_per);
1051 if (ret)
1052 return ret;
1054 ret = clk_enable(spi_imx->clk_ipg);
1055 if (ret) {
1056 clk_disable(spi_imx->clk_per);
1057 return ret;
1060 return 0;
1063 static int
1064 spi_imx_unprepare_message(struct spi_master *master, struct spi_message *msg)
1066 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1068 clk_disable(spi_imx->clk_ipg);
1069 clk_disable(spi_imx->clk_per);
1070 return 0;
1073 static int spi_imx_probe(struct platform_device *pdev)
1075 struct device_node *np = pdev->dev.of_node;
1076 const struct of_device_id *of_id =
1077 of_match_device(spi_imx_dt_ids, &pdev->dev);
1078 struct spi_imx_master *mxc_platform_info =
1079 dev_get_platdata(&pdev->dev);
1080 struct spi_master *master;
1081 struct spi_imx_data *spi_imx;
1082 struct resource *res;
1083 int i, ret, num_cs;
1085 if (!np && !mxc_platform_info) {
1086 dev_err(&pdev->dev, "can't get the platform data\n");
1087 return -EINVAL;
1090 ret = of_property_read_u32(np, "fsl,spi-num-chipselects", &num_cs);
1091 if (ret < 0) {
1092 if (mxc_platform_info)
1093 num_cs = mxc_platform_info->num_chipselect;
1094 else
1095 return ret;
1098 master = spi_alloc_master(&pdev->dev,
1099 sizeof(struct spi_imx_data) + sizeof(int) * num_cs);
1100 if (!master)
1101 return -ENOMEM;
1103 platform_set_drvdata(pdev, master);
1105 master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
1106 master->bus_num = pdev->id;
1107 master->num_chipselect = num_cs;
1109 spi_imx = spi_master_get_devdata(master);
1110 spi_imx->bitbang.master = master;
1112 for (i = 0; i < master->num_chipselect; i++) {
1113 int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
1114 if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
1115 cs_gpio = mxc_platform_info->chipselect[i];
1117 spi_imx->chipselect[i] = cs_gpio;
1118 if (!gpio_is_valid(cs_gpio))
1119 continue;
1121 ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
1122 DRIVER_NAME);
1123 if (ret) {
1124 dev_err(&pdev->dev, "can't get cs gpios\n");
1125 goto out_master_put;
1129 spi_imx->bitbang.chipselect = spi_imx_chipselect;
1130 spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
1131 spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
1132 spi_imx->bitbang.master->setup = spi_imx_setup;
1133 spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
1134 spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
1135 spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
1136 spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1138 init_completion(&spi_imx->xfer_done);
1140 spi_imx->devtype_data = of_id ? of_id->data :
1141 (struct spi_imx_devtype_data *) pdev->id_entry->driver_data;
1143 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1144 spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
1145 if (IS_ERR(spi_imx->base)) {
1146 ret = PTR_ERR(spi_imx->base);
1147 goto out_master_put;
1150 spi_imx->irq = platform_get_irq(pdev, 0);
1151 if (spi_imx->irq < 0) {
1152 ret = spi_imx->irq;
1153 goto out_master_put;
1156 ret = devm_request_irq(&pdev->dev, spi_imx->irq, spi_imx_isr, 0,
1157 dev_name(&pdev->dev), spi_imx);
1158 if (ret) {
1159 dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
1160 goto out_master_put;
1163 spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1164 if (IS_ERR(spi_imx->clk_ipg)) {
1165 ret = PTR_ERR(spi_imx->clk_ipg);
1166 goto out_master_put;
1169 spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
1170 if (IS_ERR(spi_imx->clk_per)) {
1171 ret = PTR_ERR(spi_imx->clk_per);
1172 goto out_master_put;
1175 ret = clk_prepare_enable(spi_imx->clk_per);
1176 if (ret)
1177 goto out_master_put;
1179 ret = clk_prepare_enable(spi_imx->clk_ipg);
1180 if (ret)
1181 goto out_put_per;
1183 spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);
1185 * Only validated on i.mx6 now, can remove the constrain if validated on
1186 * other chips.
1188 if (spi_imx->devtype_data == &imx51_ecspi_devtype_data
1189 && spi_imx_sdma_init(&pdev->dev, spi_imx, master, res))
1190 dev_err(&pdev->dev, "dma setup error,use pio instead\n");
1192 spi_imx->devtype_data->reset(spi_imx);
1194 spi_imx->devtype_data->intctrl(spi_imx, 0);
1196 master->dev.of_node = pdev->dev.of_node;
1197 ret = spi_bitbang_start(&spi_imx->bitbang);
1198 if (ret) {
1199 dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
1200 goto out_clk_put;
1203 dev_info(&pdev->dev, "probed\n");
1205 clk_disable(spi_imx->clk_ipg);
1206 clk_disable(spi_imx->clk_per);
1207 return ret;
1209 out_clk_put:
1210 clk_disable_unprepare(spi_imx->clk_ipg);
1211 out_put_per:
1212 clk_disable_unprepare(spi_imx->clk_per);
1213 out_master_put:
1214 spi_master_put(master);
1216 return ret;
1219 static int spi_imx_remove(struct platform_device *pdev)
1221 struct spi_master *master = platform_get_drvdata(pdev);
1222 struct spi_imx_data *spi_imx = spi_master_get_devdata(master);
1224 spi_bitbang_stop(&spi_imx->bitbang);
1226 writel(0, spi_imx->base + MXC_CSPICTRL);
1227 clk_unprepare(spi_imx->clk_ipg);
1228 clk_unprepare(spi_imx->clk_per);
1229 spi_imx_sdma_exit(spi_imx);
1230 spi_master_put(master);
1232 return 0;
1235 static struct platform_driver spi_imx_driver = {
1236 .driver = {
1237 .name = DRIVER_NAME,
1238 .of_match_table = spi_imx_dt_ids,
1240 .id_table = spi_imx_devtype,
1241 .probe = spi_imx_probe,
1242 .remove = spi_imx_remove,
1244 module_platform_driver(spi_imx_driver);
1246 MODULE_DESCRIPTION("SPI Master Controller driver");
1247 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1248 MODULE_LICENSE("GPL");
1249 MODULE_ALIAS("platform:" DRIVER_NAME);