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/err.h>
25 #include <linux/gpio.h>
26 #include <linux/init.h>
27 #include <linux/interrupt.h>
29 #include <linux/irq.h>
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/platform_device.h>
33 #include <linux/spi/spi.h>
34 #include <linux/spi/spi_bitbang.h>
35 #include <linux/types.h>
39 #define DRIVER_NAME "spi_imx"
41 #define MXC_CSPIRXDATA 0x00
42 #define MXC_CSPITXDATA 0x04
43 #define MXC_CSPICTRL 0x08
44 #define MXC_CSPIINT 0x0c
45 #define MXC_RESET 0x1c
47 /* generic defines to abstract from the different register layouts */
48 #define MXC_INT_RR (1 << 0) /* Receive data ready interrupt */
49 #define MXC_INT_TE (1 << 1) /* Transmit FIFO empty interrupt */
51 struct spi_imx_config
{
52 unsigned int speed_hz
;
59 struct spi_bitbang bitbang
;
61 struct completion xfer_done
;
65 unsigned long spi_clk
;
69 void (*tx
)(struct spi_imx_data
*);
70 void (*rx
)(struct spi_imx_data
*);
73 unsigned int txfifo
; /* number of words pushed in tx FIFO */
75 /* SoC specific functions */
76 void (*intctrl
)(struct spi_imx_data
*, int);
77 int (*config
)(struct spi_imx_data
*, struct spi_imx_config
*);
78 void (*trigger
)(struct spi_imx_data
*);
79 int (*rx_available
)(struct spi_imx_data
*);
82 #define MXC_SPI_BUF_RX(type) \
83 static void spi_imx_buf_rx_##type(struct spi_imx_data *spi_imx) \
85 unsigned int val = readl(spi_imx->base + MXC_CSPIRXDATA); \
87 if (spi_imx->rx_buf) { \
88 *(type *)spi_imx->rx_buf = val; \
89 spi_imx->rx_buf += sizeof(type); \
93 #define MXC_SPI_BUF_TX(type) \
94 static void spi_imx_buf_tx_##type(struct spi_imx_data *spi_imx) \
98 if (spi_imx->tx_buf) { \
99 val = *(type *)spi_imx->tx_buf; \
100 spi_imx->tx_buf += sizeof(type); \
103 spi_imx->count -= sizeof(type); \
105 writel(val, spi_imx->base + MXC_CSPITXDATA); \
115 /* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
116 * (which is currently not the case in this driver)
118 static int mxc_clkdivs
[] = {0, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128, 192,
119 256, 384, 512, 768, 1024};
122 static unsigned int spi_imx_clkdiv_1(unsigned int fin
,
132 for (i
= 2; i
< max
; i
++)
133 if (fspi
* mxc_clkdivs
[i
] >= fin
)
139 /* MX1, MX31, MX35 */
140 static unsigned int spi_imx_clkdiv_2(unsigned int fin
,
145 for (i
= 0; i
< 7; i
++) {
146 if (fspi
* div
>= fin
)
154 #define MX31_INTREG_TEEN (1 << 0)
155 #define MX31_INTREG_RREN (1 << 3)
157 #define MX31_CSPICTRL_ENABLE (1 << 0)
158 #define MX31_CSPICTRL_MASTER (1 << 1)
159 #define MX31_CSPICTRL_XCH (1 << 2)
160 #define MX31_CSPICTRL_POL (1 << 4)
161 #define MX31_CSPICTRL_PHA (1 << 5)
162 #define MX31_CSPICTRL_SSCTL (1 << 6)
163 #define MX31_CSPICTRL_SSPOL (1 << 7)
164 #define MX31_CSPICTRL_BC_SHIFT 8
165 #define MX35_CSPICTRL_BL_SHIFT 20
166 #define MX31_CSPICTRL_CS_SHIFT 24
167 #define MX35_CSPICTRL_CS_SHIFT 12
168 #define MX31_CSPICTRL_DR_SHIFT 16
170 #define MX31_CSPISTATUS 0x14
171 #define MX31_STATUS_RR (1 << 3)
173 /* These functions also work for the i.MX35, but be aware that
174 * the i.MX35 has a slightly different register layout for bits
175 * we do not use here.
177 static void mx31_intctrl(struct spi_imx_data
*spi_imx
, int enable
)
179 unsigned int val
= 0;
181 if (enable
& MXC_INT_TE
)
182 val
|= MX31_INTREG_TEEN
;
183 if (enable
& MXC_INT_RR
)
184 val
|= MX31_INTREG_RREN
;
186 writel(val
, spi_imx
->base
+ MXC_CSPIINT
);
189 static void mx31_trigger(struct spi_imx_data
*spi_imx
)
193 reg
= readl(spi_imx
->base
+ MXC_CSPICTRL
);
194 reg
|= MX31_CSPICTRL_XCH
;
195 writel(reg
, spi_imx
->base
+ MXC_CSPICTRL
);
198 static int mx31_config(struct spi_imx_data
*spi_imx
,
199 struct spi_imx_config
*config
)
201 unsigned int reg
= MX31_CSPICTRL_ENABLE
| MX31_CSPICTRL_MASTER
;
203 reg
|= spi_imx_clkdiv_2(spi_imx
->spi_clk
, config
->speed_hz
) <<
204 MX31_CSPICTRL_DR_SHIFT
;
207 reg
|= (config
->bpw
- 1) << MX31_CSPICTRL_BC_SHIFT
;
208 else if (cpu_is_mx35()) {
209 reg
|= (config
->bpw
- 1) << MX35_CSPICTRL_BL_SHIFT
;
210 reg
|= MX31_CSPICTRL_SSCTL
;
213 if (config
->mode
& SPI_CPHA
)
214 reg
|= MX31_CSPICTRL_PHA
;
215 if (config
->mode
& SPI_CPOL
)
216 reg
|= MX31_CSPICTRL_POL
;
217 if (config
->mode
& SPI_CS_HIGH
)
218 reg
|= MX31_CSPICTRL_SSPOL
;
219 if (config
->cs
< 0) {
221 reg
|= (config
->cs
+ 32) << MX31_CSPICTRL_CS_SHIFT
;
222 else if (cpu_is_mx35())
223 reg
|= (config
->cs
+ 32) << MX35_CSPICTRL_CS_SHIFT
;
226 writel(reg
, spi_imx
->base
+ MXC_CSPICTRL
);
231 static int mx31_rx_available(struct spi_imx_data
*spi_imx
)
233 return readl(spi_imx
->base
+ MX31_CSPISTATUS
) & MX31_STATUS_RR
;
236 #define MX27_INTREG_RR (1 << 4)
237 #define MX27_INTREG_TEEN (1 << 9)
238 #define MX27_INTREG_RREN (1 << 13)
240 #define MX27_CSPICTRL_POL (1 << 5)
241 #define MX27_CSPICTRL_PHA (1 << 6)
242 #define MX27_CSPICTRL_SSPOL (1 << 8)
243 #define MX27_CSPICTRL_XCH (1 << 9)
244 #define MX27_CSPICTRL_ENABLE (1 << 10)
245 #define MX27_CSPICTRL_MASTER (1 << 11)
246 #define MX27_CSPICTRL_DR_SHIFT 14
247 #define MX27_CSPICTRL_CS_SHIFT 19
249 static void mx27_intctrl(struct spi_imx_data
*spi_imx
, int enable
)
251 unsigned int val
= 0;
253 if (enable
& MXC_INT_TE
)
254 val
|= MX27_INTREG_TEEN
;
255 if (enable
& MXC_INT_RR
)
256 val
|= MX27_INTREG_RREN
;
258 writel(val
, spi_imx
->base
+ MXC_CSPIINT
);
261 static void mx27_trigger(struct spi_imx_data
*spi_imx
)
265 reg
= readl(spi_imx
->base
+ MXC_CSPICTRL
);
266 reg
|= MX27_CSPICTRL_XCH
;
267 writel(reg
, spi_imx
->base
+ MXC_CSPICTRL
);
270 static int mx27_config(struct spi_imx_data
*spi_imx
,
271 struct spi_imx_config
*config
)
273 unsigned int reg
= MX27_CSPICTRL_ENABLE
| MX27_CSPICTRL_MASTER
;
275 reg
|= spi_imx_clkdiv_1(spi_imx
->spi_clk
, config
->speed_hz
) <<
276 MX27_CSPICTRL_DR_SHIFT
;
277 reg
|= config
->bpw
- 1;
279 if (config
->mode
& SPI_CPHA
)
280 reg
|= MX27_CSPICTRL_PHA
;
281 if (config
->mode
& SPI_CPOL
)
282 reg
|= MX27_CSPICTRL_POL
;
283 if (config
->mode
& SPI_CS_HIGH
)
284 reg
|= MX27_CSPICTRL_SSPOL
;
286 reg
|= (config
->cs
+ 32) << MX27_CSPICTRL_CS_SHIFT
;
288 writel(reg
, spi_imx
->base
+ MXC_CSPICTRL
);
293 static int mx27_rx_available(struct spi_imx_data
*spi_imx
)
295 return readl(spi_imx
->base
+ MXC_CSPIINT
) & MX27_INTREG_RR
;
298 #define MX1_INTREG_RR (1 << 3)
299 #define MX1_INTREG_TEEN (1 << 8)
300 #define MX1_INTREG_RREN (1 << 11)
302 #define MX1_CSPICTRL_POL (1 << 4)
303 #define MX1_CSPICTRL_PHA (1 << 5)
304 #define MX1_CSPICTRL_XCH (1 << 8)
305 #define MX1_CSPICTRL_ENABLE (1 << 9)
306 #define MX1_CSPICTRL_MASTER (1 << 10)
307 #define MX1_CSPICTRL_DR_SHIFT 13
309 static void mx1_intctrl(struct spi_imx_data
*spi_imx
, int enable
)
311 unsigned int val
= 0;
313 if (enable
& MXC_INT_TE
)
314 val
|= MX1_INTREG_TEEN
;
315 if (enable
& MXC_INT_RR
)
316 val
|= MX1_INTREG_RREN
;
318 writel(val
, spi_imx
->base
+ MXC_CSPIINT
);
321 static void mx1_trigger(struct spi_imx_data
*spi_imx
)
325 reg
= readl(spi_imx
->base
+ MXC_CSPICTRL
);
326 reg
|= MX1_CSPICTRL_XCH
;
327 writel(reg
, spi_imx
->base
+ MXC_CSPICTRL
);
330 static int mx1_config(struct spi_imx_data
*spi_imx
,
331 struct spi_imx_config
*config
)
333 unsigned int reg
= MX1_CSPICTRL_ENABLE
| MX1_CSPICTRL_MASTER
;
335 reg
|= spi_imx_clkdiv_2(spi_imx
->spi_clk
, config
->speed_hz
) <<
336 MX1_CSPICTRL_DR_SHIFT
;
337 reg
|= config
->bpw
- 1;
339 if (config
->mode
& SPI_CPHA
)
340 reg
|= MX1_CSPICTRL_PHA
;
341 if (config
->mode
& SPI_CPOL
)
342 reg
|= MX1_CSPICTRL_POL
;
344 writel(reg
, spi_imx
->base
+ MXC_CSPICTRL
);
349 static int mx1_rx_available(struct spi_imx_data
*spi_imx
)
351 return readl(spi_imx
->base
+ MXC_CSPIINT
) & MX1_INTREG_RR
;
354 static void spi_imx_chipselect(struct spi_device
*spi
, int is_active
)
356 struct spi_imx_data
*spi_imx
= spi_master_get_devdata(spi
->master
);
357 int gpio
= spi_imx
->chipselect
[spi
->chip_select
];
358 int active
= is_active
!= BITBANG_CS_INACTIVE
;
359 int dev_is_lowactive
= !(spi
->mode
& SPI_CS_HIGH
);
364 gpio_set_value(gpio
, dev_is_lowactive
^ active
);
367 static void spi_imx_push(struct spi_imx_data
*spi_imx
)
369 while (spi_imx
->txfifo
< 8) {
372 spi_imx
->tx(spi_imx
);
376 spi_imx
->trigger(spi_imx
);
379 static irqreturn_t
spi_imx_isr(int irq
, void *dev_id
)
381 struct spi_imx_data
*spi_imx
= dev_id
;
383 while (spi_imx
->rx_available(spi_imx
)) {
384 spi_imx
->rx(spi_imx
);
388 if (spi_imx
->count
) {
389 spi_imx_push(spi_imx
);
393 if (spi_imx
->txfifo
) {
394 /* No data left to push, but still waiting for rx data,
395 * enable receive data available interrupt.
397 spi_imx
->intctrl(spi_imx
, MXC_INT_RR
);
401 spi_imx
->intctrl(spi_imx
, 0);
402 complete(&spi_imx
->xfer_done
);
407 static int spi_imx_setupxfer(struct spi_device
*spi
,
408 struct spi_transfer
*t
)
410 struct spi_imx_data
*spi_imx
= spi_master_get_devdata(spi
->master
);
411 struct spi_imx_config config
;
413 config
.bpw
= t
? t
->bits_per_word
: spi
->bits_per_word
;
414 config
.speed_hz
= t
? t
->speed_hz
: spi
->max_speed_hz
;
415 config
.mode
= spi
->mode
;
416 config
.cs
= spi_imx
->chipselect
[spi
->chip_select
];
418 if (!config
.speed_hz
)
419 config
.speed_hz
= spi
->max_speed_hz
;
421 config
.bpw
= spi
->bits_per_word
;
422 if (!config
.speed_hz
)
423 config
.speed_hz
= spi
->max_speed_hz
;
425 /* Initialize the functions for transfer */
426 if (config
.bpw
<= 8) {
427 spi_imx
->rx
= spi_imx_buf_rx_u8
;
428 spi_imx
->tx
= spi_imx_buf_tx_u8
;
429 } else if (config
.bpw
<= 16) {
430 spi_imx
->rx
= spi_imx_buf_rx_u16
;
431 spi_imx
->tx
= spi_imx_buf_tx_u16
;
432 } else if (config
.bpw
<= 32) {
433 spi_imx
->rx
= spi_imx_buf_rx_u32
;
434 spi_imx
->tx
= spi_imx_buf_tx_u32
;
438 spi_imx
->config(spi_imx
, &config
);
443 static int spi_imx_transfer(struct spi_device
*spi
,
444 struct spi_transfer
*transfer
)
446 struct spi_imx_data
*spi_imx
= spi_master_get_devdata(spi
->master
);
448 spi_imx
->tx_buf
= transfer
->tx_buf
;
449 spi_imx
->rx_buf
= transfer
->rx_buf
;
450 spi_imx
->count
= transfer
->len
;
453 init_completion(&spi_imx
->xfer_done
);
455 spi_imx_push(spi_imx
);
457 spi_imx
->intctrl(spi_imx
, MXC_INT_TE
);
459 wait_for_completion(&spi_imx
->xfer_done
);
461 return transfer
->len
;
464 static int spi_imx_setup(struct spi_device
*spi
)
466 struct spi_imx_data
*spi_imx
= spi_master_get_devdata(spi
->master
);
467 int gpio
= spi_imx
->chipselect
[spi
->chip_select
];
469 pr_debug("%s: mode %d, %u bpw, %d hz\n", __func__
,
470 spi
->mode
, spi
->bits_per_word
, spi
->max_speed_hz
);
473 gpio_direction_output(gpio
, spi
->mode
& SPI_CS_HIGH
? 0 : 1);
475 spi_imx_chipselect(spi
, BITBANG_CS_INACTIVE
);
480 static void spi_imx_cleanup(struct spi_device
*spi
)
484 static int __init
spi_imx_probe(struct platform_device
*pdev
)
486 struct spi_imx_master
*mxc_platform_info
;
487 struct spi_master
*master
;
488 struct spi_imx_data
*spi_imx
;
489 struct resource
*res
;
492 mxc_platform_info
= (struct spi_imx_master
*)pdev
->dev
.platform_data
;
493 if (!mxc_platform_info
) {
494 dev_err(&pdev
->dev
, "can't get the platform data\n");
498 master
= spi_alloc_master(&pdev
->dev
, sizeof(struct spi_imx_data
));
502 platform_set_drvdata(pdev
, master
);
504 master
->bus_num
= pdev
->id
;
505 master
->num_chipselect
= mxc_platform_info
->num_chipselect
;
507 spi_imx
= spi_master_get_devdata(master
);
508 spi_imx
->bitbang
.master
= spi_master_get(master
);
509 spi_imx
->chipselect
= mxc_platform_info
->chipselect
;
511 for (i
= 0; i
< master
->num_chipselect
; i
++) {
512 if (spi_imx
->chipselect
[i
] < 0)
514 ret
= gpio_request(spi_imx
->chipselect
[i
], DRIVER_NAME
);
518 if (spi_imx
->chipselect
[i
] >= 0)
519 gpio_free(spi_imx
->chipselect
[i
--]);
520 dev_err(&pdev
->dev
, "can't get cs gpios");
525 spi_imx
->bitbang
.chipselect
= spi_imx_chipselect
;
526 spi_imx
->bitbang
.setup_transfer
= spi_imx_setupxfer
;
527 spi_imx
->bitbang
.txrx_bufs
= spi_imx_transfer
;
528 spi_imx
->bitbang
.master
->setup
= spi_imx_setup
;
529 spi_imx
->bitbang
.master
->cleanup
= spi_imx_cleanup
;
530 spi_imx
->bitbang
.master
->mode_bits
= SPI_CPOL
| SPI_CPHA
| SPI_CS_HIGH
;
532 init_completion(&spi_imx
->xfer_done
);
534 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
536 dev_err(&pdev
->dev
, "can't get platform resource\n");
541 if (!request_mem_region(res
->start
, resource_size(res
), pdev
->name
)) {
542 dev_err(&pdev
->dev
, "request_mem_region failed\n");
547 spi_imx
->base
= ioremap(res
->start
, resource_size(res
));
548 if (!spi_imx
->base
) {
550 goto out_release_mem
;
553 spi_imx
->irq
= platform_get_irq(pdev
, 0);
559 ret
= request_irq(spi_imx
->irq
, spi_imx_isr
, 0, DRIVER_NAME
, spi_imx
);
561 dev_err(&pdev
->dev
, "can't get irq%d: %d\n", spi_imx
->irq
, ret
);
565 if (cpu_is_mx31() || cpu_is_mx35()) {
566 spi_imx
->intctrl
= mx31_intctrl
;
567 spi_imx
->config
= mx31_config
;
568 spi_imx
->trigger
= mx31_trigger
;
569 spi_imx
->rx_available
= mx31_rx_available
;
570 } else if (cpu_is_mx27() || cpu_is_mx21()) {
571 spi_imx
->intctrl
= mx27_intctrl
;
572 spi_imx
->config
= mx27_config
;
573 spi_imx
->trigger
= mx27_trigger
;
574 spi_imx
->rx_available
= mx27_rx_available
;
575 } else if (cpu_is_mx1()) {
576 spi_imx
->intctrl
= mx1_intctrl
;
577 spi_imx
->config
= mx1_config
;
578 spi_imx
->trigger
= mx1_trigger
;
579 spi_imx
->rx_available
= mx1_rx_available
;
583 spi_imx
->clk
= clk_get(&pdev
->dev
, NULL
);
584 if (IS_ERR(spi_imx
->clk
)) {
585 dev_err(&pdev
->dev
, "unable to get clock\n");
586 ret
= PTR_ERR(spi_imx
->clk
);
590 clk_enable(spi_imx
->clk
);
591 spi_imx
->spi_clk
= clk_get_rate(spi_imx
->clk
);
593 if (!cpu_is_mx31() || !cpu_is_mx35())
594 writel(1, spi_imx
->base
+ MXC_RESET
);
596 spi_imx
->intctrl(spi_imx
, 0);
598 ret
= spi_bitbang_start(&spi_imx
->bitbang
);
600 dev_err(&pdev
->dev
, "bitbang start failed with %d\n", ret
);
604 dev_info(&pdev
->dev
, "probed\n");
609 clk_disable(spi_imx
->clk
);
610 clk_put(spi_imx
->clk
);
612 free_irq(spi_imx
->irq
, spi_imx
);
614 iounmap(spi_imx
->base
);
616 release_mem_region(res
->start
, resource_size(res
));
618 for (i
= 0; i
< master
->num_chipselect
; i
++)
619 if (spi_imx
->chipselect
[i
] >= 0)
620 gpio_free(spi_imx
->chipselect
[i
]);
622 spi_master_put(master
);
624 platform_set_drvdata(pdev
, NULL
);
628 static int __exit
spi_imx_remove(struct platform_device
*pdev
)
630 struct spi_master
*master
= platform_get_drvdata(pdev
);
631 struct resource
*res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
632 struct spi_imx_data
*spi_imx
= spi_master_get_devdata(master
);
635 spi_bitbang_stop(&spi_imx
->bitbang
);
637 writel(0, spi_imx
->base
+ MXC_CSPICTRL
);
638 clk_disable(spi_imx
->clk
);
639 clk_put(spi_imx
->clk
);
640 free_irq(spi_imx
->irq
, spi_imx
);
641 iounmap(spi_imx
->base
);
643 for (i
= 0; i
< master
->num_chipselect
; i
++)
644 if (spi_imx
->chipselect
[i
] >= 0)
645 gpio_free(spi_imx
->chipselect
[i
]);
647 spi_master_put(master
);
649 release_mem_region(res
->start
, resource_size(res
));
651 platform_set_drvdata(pdev
, NULL
);
656 static struct platform_driver spi_imx_driver
= {
659 .owner
= THIS_MODULE
,
661 .probe
= spi_imx_probe
,
662 .remove
= __exit_p(spi_imx_remove
),
665 static int __init
spi_imx_init(void)
667 return platform_driver_register(&spi_imx_driver
);
670 static void __exit
spi_imx_exit(void)
672 platform_driver_unregister(&spi_imx_driver
);
675 module_init(spi_imx_init
);
676 module_exit(spi_imx_exit
);
678 MODULE_DESCRIPTION("SPI Master Controller driver");
679 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
680 MODULE_LICENSE("GPL");