OMAPDSS: VENC: fix NULL pointer dereference in DSS2 VENC sysfs debug attr on OMAP4
[zen-stable.git] / drivers / mmc / host / sdhci-s3c.c
blob1af756ee0f9ab5e43db1a348505021a6fd5eee28
1 /* linux/drivers/mmc/host/sdhci-s3c.c
3 * Copyright 2008 Openmoko Inc.
4 * Copyright 2008 Simtec Electronics
5 * Ben Dooks <ben@simtec.co.uk>
6 * http://armlinux.simtec.co.uk/
8 * SDHCI (HSMMC) support for Samsung SoC
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
15 #include <linux/delay.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21 #include <linux/gpio.h>
22 #include <linux/module.h>
24 #include <linux/mmc/host.h>
26 #include <plat/sdhci.h>
27 #include <plat/regs-sdhci.h>
29 #include "sdhci.h"
31 #define MAX_BUS_CLK (4)
33 /**
34 * struct sdhci_s3c - S3C SDHCI instance
35 * @host: The SDHCI host created
36 * @pdev: The platform device we where created from.
37 * @ioarea: The resource created when we claimed the IO area.
38 * @pdata: The platform data for this controller.
39 * @cur_clk: The index of the current bus clock.
40 * @clk_io: The clock for the internal bus interface.
41 * @clk_bus: The clocks that are available for the SD/MMC bus clock.
43 struct sdhci_s3c {
44 struct sdhci_host *host;
45 struct platform_device *pdev;
46 struct resource *ioarea;
47 struct s3c_sdhci_platdata *pdata;
48 unsigned int cur_clk;
49 int ext_cd_irq;
50 int ext_cd_gpio;
52 struct clk *clk_io;
53 struct clk *clk_bus[MAX_BUS_CLK];
56 static inline struct sdhci_s3c *to_s3c(struct sdhci_host *host)
58 return sdhci_priv(host);
61 /**
62 * get_curclk - convert ctrl2 register to clock source number
63 * @ctrl2: Control2 register value.
65 static u32 get_curclk(u32 ctrl2)
67 ctrl2 &= S3C_SDHCI_CTRL2_SELBASECLK_MASK;
68 ctrl2 >>= S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
70 return ctrl2;
73 static void sdhci_s3c_check_sclk(struct sdhci_host *host)
75 struct sdhci_s3c *ourhost = to_s3c(host);
76 u32 tmp = readl(host->ioaddr + S3C_SDHCI_CONTROL2);
78 if (get_curclk(tmp) != ourhost->cur_clk) {
79 dev_dbg(&ourhost->pdev->dev, "restored ctrl2 clock setting\n");
81 tmp &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK;
82 tmp |= ourhost->cur_clk << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
83 writel(tmp, host->ioaddr + S3C_SDHCI_CONTROL2);
87 /**
88 * sdhci_s3c_get_max_clk - callback to get maximum clock frequency.
89 * @host: The SDHCI host instance.
91 * Callback to return the maximum clock rate acheivable by the controller.
93 static unsigned int sdhci_s3c_get_max_clk(struct sdhci_host *host)
95 struct sdhci_s3c *ourhost = to_s3c(host);
96 struct clk *busclk;
97 unsigned int rate, max;
98 int clk;
100 /* note, a reset will reset the clock source */
102 sdhci_s3c_check_sclk(host);
104 for (max = 0, clk = 0; clk < MAX_BUS_CLK; clk++) {
105 busclk = ourhost->clk_bus[clk];
106 if (!busclk)
107 continue;
109 rate = clk_get_rate(busclk);
110 if (rate > max)
111 max = rate;
114 return max;
118 * sdhci_s3c_consider_clock - consider one the bus clocks for current setting
119 * @ourhost: Our SDHCI instance.
120 * @src: The source clock index.
121 * @wanted: The clock frequency wanted.
123 static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost,
124 unsigned int src,
125 unsigned int wanted)
127 unsigned long rate;
128 struct clk *clksrc = ourhost->clk_bus[src];
129 int div;
131 if (!clksrc)
132 return UINT_MAX;
135 * Clock divider's step is different as 1 from that of host controller
136 * when 'clk_type' is S3C_SDHCI_CLK_DIV_EXTERNAL.
138 if (ourhost->pdata->clk_type) {
139 rate = clk_round_rate(clksrc, wanted);
140 return wanted - rate;
143 rate = clk_get_rate(clksrc);
145 for (div = 1; div < 256; div *= 2) {
146 if ((rate / div) <= wanted)
147 break;
150 dev_dbg(&ourhost->pdev->dev, "clk %d: rate %ld, want %d, got %ld\n",
151 src, rate, wanted, rate / div);
153 return (wanted - (rate / div));
157 * sdhci_s3c_set_clock - callback on clock change
158 * @host: The SDHCI host being changed
159 * @clock: The clock rate being requested.
161 * When the card's clock is going to be changed, look at the new frequency
162 * and find the best clock source to go with it.
164 static void sdhci_s3c_set_clock(struct sdhci_host *host, unsigned int clock)
166 struct sdhci_s3c *ourhost = to_s3c(host);
167 unsigned int best = UINT_MAX;
168 unsigned int delta;
169 int best_src = 0;
170 int src;
171 u32 ctrl;
173 /* don't bother if the clock is going off. */
174 if (clock == 0)
175 return;
177 for (src = 0; src < MAX_BUS_CLK; src++) {
178 delta = sdhci_s3c_consider_clock(ourhost, src, clock);
179 if (delta < best) {
180 best = delta;
181 best_src = src;
185 dev_dbg(&ourhost->pdev->dev,
186 "selected source %d, clock %d, delta %d\n",
187 best_src, clock, best);
189 /* select the new clock source */
191 if (ourhost->cur_clk != best_src) {
192 struct clk *clk = ourhost->clk_bus[best_src];
194 /* turn clock off to card before changing clock source */
195 writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL);
197 ourhost->cur_clk = best_src;
198 host->max_clk = clk_get_rate(clk);
200 ctrl = readl(host->ioaddr + S3C_SDHCI_CONTROL2);
201 ctrl &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK;
202 ctrl |= best_src << S3C_SDHCI_CTRL2_SELBASECLK_SHIFT;
203 writel(ctrl, host->ioaddr + S3C_SDHCI_CONTROL2);
206 /* reprogram default hardware configuration */
207 writel(S3C64XX_SDHCI_CONTROL4_DRIVE_9mA,
208 host->ioaddr + S3C64XX_SDHCI_CONTROL4);
210 ctrl = readl(host->ioaddr + S3C_SDHCI_CONTROL2);
211 ctrl |= (S3C64XX_SDHCI_CTRL2_ENSTAASYNCCLR |
212 S3C64XX_SDHCI_CTRL2_ENCMDCNFMSK |
213 S3C_SDHCI_CTRL2_ENFBCLKRX |
214 S3C_SDHCI_CTRL2_DFCNT_NONE |
215 S3C_SDHCI_CTRL2_ENCLKOUTHOLD);
216 writel(ctrl, host->ioaddr + S3C_SDHCI_CONTROL2);
218 /* reconfigure the controller for new clock rate */
219 ctrl = (S3C_SDHCI_CTRL3_FCSEL1 | S3C_SDHCI_CTRL3_FCSEL0);
220 if (clock < 25 * 1000000)
221 ctrl |= (S3C_SDHCI_CTRL3_FCSEL3 | S3C_SDHCI_CTRL3_FCSEL2);
222 writel(ctrl, host->ioaddr + S3C_SDHCI_CONTROL3);
226 * sdhci_s3c_get_min_clock - callback to get minimal supported clock value
227 * @host: The SDHCI host being queried
229 * To init mmc host properly a minimal clock value is needed. For high system
230 * bus clock's values the standard formula gives values out of allowed range.
231 * The clock still can be set to lower values, if clock source other then
232 * system bus is selected.
234 static unsigned int sdhci_s3c_get_min_clock(struct sdhci_host *host)
236 struct sdhci_s3c *ourhost = to_s3c(host);
237 unsigned int delta, min = UINT_MAX;
238 int src;
240 for (src = 0; src < MAX_BUS_CLK; src++) {
241 delta = sdhci_s3c_consider_clock(ourhost, src, 0);
242 if (delta == UINT_MAX)
243 continue;
244 /* delta is a negative value in this case */
245 if (-delta < min)
246 min = -delta;
248 return min;
251 /* sdhci_cmu_get_max_clk - callback to get maximum clock frequency.*/
252 static unsigned int sdhci_cmu_get_max_clock(struct sdhci_host *host)
254 struct sdhci_s3c *ourhost = to_s3c(host);
256 return clk_round_rate(ourhost->clk_bus[ourhost->cur_clk], UINT_MAX);
259 /* sdhci_cmu_get_min_clock - callback to get minimal supported clock value. */
260 static unsigned int sdhci_cmu_get_min_clock(struct sdhci_host *host)
262 struct sdhci_s3c *ourhost = to_s3c(host);
265 * initial clock can be in the frequency range of
266 * 100KHz-400KHz, so we set it as max value.
268 return clk_round_rate(ourhost->clk_bus[ourhost->cur_clk], 400000);
271 /* sdhci_cmu_set_clock - callback on clock change.*/
272 static void sdhci_cmu_set_clock(struct sdhci_host *host, unsigned int clock)
274 struct sdhci_s3c *ourhost = to_s3c(host);
276 /* don't bother if the clock is going off */
277 if (clock == 0)
278 return;
280 sdhci_s3c_set_clock(host, clock);
282 clk_set_rate(ourhost->clk_bus[ourhost->cur_clk], clock);
284 host->clock = clock;
288 * sdhci_s3c_platform_8bit_width - support 8bit buswidth
289 * @host: The SDHCI host being queried
290 * @width: MMC_BUS_WIDTH_ macro for the bus width being requested
292 * We have 8-bit width support but is not a v3 controller.
293 * So we add platform_8bit_width() and support 8bit width.
295 static int sdhci_s3c_platform_8bit_width(struct sdhci_host *host, int width)
297 u8 ctrl;
299 ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
301 switch (width) {
302 case MMC_BUS_WIDTH_8:
303 ctrl |= SDHCI_CTRL_8BITBUS;
304 ctrl &= ~SDHCI_CTRL_4BITBUS;
305 break;
306 case MMC_BUS_WIDTH_4:
307 ctrl |= SDHCI_CTRL_4BITBUS;
308 ctrl &= ~SDHCI_CTRL_8BITBUS;
309 break;
310 default:
311 ctrl &= ~SDHCI_CTRL_4BITBUS;
312 ctrl &= ~SDHCI_CTRL_8BITBUS;
313 break;
316 sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
318 return 0;
321 static struct sdhci_ops sdhci_s3c_ops = {
322 .get_max_clock = sdhci_s3c_get_max_clk,
323 .set_clock = sdhci_s3c_set_clock,
324 .get_min_clock = sdhci_s3c_get_min_clock,
325 .platform_8bit_width = sdhci_s3c_platform_8bit_width,
328 static void sdhci_s3c_notify_change(struct platform_device *dev, int state)
330 struct sdhci_host *host = platform_get_drvdata(dev);
331 unsigned long flags;
333 if (host) {
334 spin_lock_irqsave(&host->lock, flags);
335 if (state) {
336 dev_dbg(&dev->dev, "card inserted.\n");
337 host->flags &= ~SDHCI_DEVICE_DEAD;
338 host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
339 } else {
340 dev_dbg(&dev->dev, "card removed.\n");
341 host->flags |= SDHCI_DEVICE_DEAD;
342 host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
344 tasklet_schedule(&host->card_tasklet);
345 spin_unlock_irqrestore(&host->lock, flags);
349 static irqreturn_t sdhci_s3c_gpio_card_detect_thread(int irq, void *dev_id)
351 struct sdhci_s3c *sc = dev_id;
352 int status = gpio_get_value(sc->ext_cd_gpio);
353 if (sc->pdata->ext_cd_gpio_invert)
354 status = !status;
355 sdhci_s3c_notify_change(sc->pdev, status);
356 return IRQ_HANDLED;
359 static void sdhci_s3c_setup_card_detect_gpio(struct sdhci_s3c *sc)
361 struct s3c_sdhci_platdata *pdata = sc->pdata;
362 struct device *dev = &sc->pdev->dev;
364 if (gpio_request(pdata->ext_cd_gpio, "SDHCI EXT CD") == 0) {
365 sc->ext_cd_gpio = pdata->ext_cd_gpio;
366 sc->ext_cd_irq = gpio_to_irq(pdata->ext_cd_gpio);
367 if (sc->ext_cd_irq &&
368 request_threaded_irq(sc->ext_cd_irq, NULL,
369 sdhci_s3c_gpio_card_detect_thread,
370 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
371 dev_name(dev), sc) == 0) {
372 int status = gpio_get_value(sc->ext_cd_gpio);
373 if (pdata->ext_cd_gpio_invert)
374 status = !status;
375 sdhci_s3c_notify_change(sc->pdev, status);
376 } else {
377 dev_warn(dev, "cannot request irq for card detect\n");
378 sc->ext_cd_irq = 0;
380 } else {
381 dev_err(dev, "cannot request gpio for card detect\n");
385 static int __devinit sdhci_s3c_probe(struct platform_device *pdev)
387 struct s3c_sdhci_platdata *pdata = pdev->dev.platform_data;
388 struct device *dev = &pdev->dev;
389 struct sdhci_host *host;
390 struct sdhci_s3c *sc;
391 struct resource *res;
392 int ret, irq, ptr, clks;
394 if (!pdata) {
395 dev_err(dev, "no device data specified\n");
396 return -ENOENT;
399 irq = platform_get_irq(pdev, 0);
400 if (irq < 0) {
401 dev_err(dev, "no irq specified\n");
402 return irq;
405 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
406 if (!res) {
407 dev_err(dev, "no memory specified\n");
408 return -ENOENT;
411 host = sdhci_alloc_host(dev, sizeof(struct sdhci_s3c));
412 if (IS_ERR(host)) {
413 dev_err(dev, "sdhci_alloc_host() failed\n");
414 return PTR_ERR(host);
417 sc = sdhci_priv(host);
419 sc->host = host;
420 sc->pdev = pdev;
421 sc->pdata = pdata;
422 sc->ext_cd_gpio = -1; /* invalid gpio number */
424 platform_set_drvdata(pdev, host);
426 sc->clk_io = clk_get(dev, "hsmmc");
427 if (IS_ERR(sc->clk_io)) {
428 dev_err(dev, "failed to get io clock\n");
429 ret = PTR_ERR(sc->clk_io);
430 goto err_io_clk;
433 /* enable the local io clock and keep it running for the moment. */
434 clk_enable(sc->clk_io);
436 for (clks = 0, ptr = 0; ptr < MAX_BUS_CLK; ptr++) {
437 struct clk *clk;
438 char name[14];
440 snprintf(name, 14, "mmc_busclk.%d", ptr);
441 clk = clk_get(dev, name);
442 if (IS_ERR(clk)) {
443 continue;
446 clks++;
447 sc->clk_bus[ptr] = clk;
450 * save current clock index to know which clock bus
451 * is used later in overriding functions.
453 sc->cur_clk = ptr;
455 clk_enable(clk);
457 dev_info(dev, "clock source %d: %s (%ld Hz)\n",
458 ptr, name, clk_get_rate(clk));
461 if (clks == 0) {
462 dev_err(dev, "failed to find any bus clocks\n");
463 ret = -ENOENT;
464 goto err_no_busclks;
467 sc->ioarea = request_mem_region(res->start, resource_size(res),
468 mmc_hostname(host->mmc));
469 if (!sc->ioarea) {
470 dev_err(dev, "failed to reserve register area\n");
471 ret = -ENXIO;
472 goto err_req_regs;
475 host->ioaddr = ioremap_nocache(res->start, resource_size(res));
476 if (!host->ioaddr) {
477 dev_err(dev, "failed to map registers\n");
478 ret = -ENXIO;
479 goto err_req_regs;
482 /* Ensure we have minimal gpio selected CMD/CLK/Detect */
483 if (pdata->cfg_gpio)
484 pdata->cfg_gpio(pdev, pdata->max_width);
486 host->hw_name = "samsung-hsmmc";
487 host->ops = &sdhci_s3c_ops;
488 host->quirks = 0;
489 host->irq = irq;
491 /* Setup quirks for the controller */
492 host->quirks |= SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC;
493 host->quirks |= SDHCI_QUIRK_NO_HISPD_BIT;
495 #ifndef CONFIG_MMC_SDHCI_S3C_DMA
497 /* we currently see overruns on errors, so disable the SDMA
498 * support as well. */
499 host->quirks |= SDHCI_QUIRK_BROKEN_DMA;
501 #endif /* CONFIG_MMC_SDHCI_S3C_DMA */
503 /* It seems we do not get an DATA transfer complete on non-busy
504 * transfers, not sure if this is a problem with this specific
505 * SDHCI block, or a missing configuration that needs to be set. */
506 host->quirks |= SDHCI_QUIRK_NO_BUSY_IRQ;
508 /* This host supports the Auto CMD12 */
509 host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12;
511 /* Samsung SoCs need BROKEN_ADMA_ZEROLEN_DESC */
512 host->quirks |= SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC;
514 if (pdata->cd_type == S3C_SDHCI_CD_NONE ||
515 pdata->cd_type == S3C_SDHCI_CD_PERMANENT)
516 host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
518 if (pdata->cd_type == S3C_SDHCI_CD_PERMANENT)
519 host->mmc->caps = MMC_CAP_NONREMOVABLE;
521 if (pdata->host_caps)
522 host->mmc->caps |= pdata->host_caps;
524 if (pdata->pm_caps)
525 host->mmc->pm_caps |= pdata->pm_caps;
527 host->quirks |= (SDHCI_QUIRK_32BIT_DMA_ADDR |
528 SDHCI_QUIRK_32BIT_DMA_SIZE);
530 /* HSMMC on Samsung SoCs uses SDCLK as timeout clock */
531 host->quirks |= SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK;
534 * If controller does not have internal clock divider,
535 * we can use overriding functions instead of default.
537 if (pdata->clk_type) {
538 sdhci_s3c_ops.set_clock = sdhci_cmu_set_clock;
539 sdhci_s3c_ops.get_min_clock = sdhci_cmu_get_min_clock;
540 sdhci_s3c_ops.get_max_clock = sdhci_cmu_get_max_clock;
543 /* It supports additional host capabilities if needed */
544 if (pdata->host_caps)
545 host->mmc->caps |= pdata->host_caps;
547 ret = sdhci_add_host(host);
548 if (ret) {
549 dev_err(dev, "sdhci_add_host() failed\n");
550 goto err_add_host;
553 /* The following two methods of card detection might call
554 sdhci_s3c_notify_change() immediately, so they can be called
555 only after sdhci_add_host(). Setup errors are ignored. */
556 if (pdata->cd_type == S3C_SDHCI_CD_EXTERNAL && pdata->ext_cd_init)
557 pdata->ext_cd_init(&sdhci_s3c_notify_change);
558 if (pdata->cd_type == S3C_SDHCI_CD_GPIO &&
559 gpio_is_valid(pdata->ext_cd_gpio))
560 sdhci_s3c_setup_card_detect_gpio(sc);
562 return 0;
564 err_add_host:
565 release_resource(sc->ioarea);
566 kfree(sc->ioarea);
568 err_req_regs:
569 for (ptr = 0; ptr < MAX_BUS_CLK; ptr++) {
570 if (sc->clk_bus[ptr]) {
571 clk_disable(sc->clk_bus[ptr]);
572 clk_put(sc->clk_bus[ptr]);
576 err_no_busclks:
577 clk_disable(sc->clk_io);
578 clk_put(sc->clk_io);
580 err_io_clk:
581 sdhci_free_host(host);
583 return ret;
586 static int __devexit sdhci_s3c_remove(struct platform_device *pdev)
588 struct s3c_sdhci_platdata *pdata = pdev->dev.platform_data;
589 struct sdhci_host *host = platform_get_drvdata(pdev);
590 struct sdhci_s3c *sc = sdhci_priv(host);
591 int ptr;
593 if (pdata->cd_type == S3C_SDHCI_CD_EXTERNAL && pdata->ext_cd_cleanup)
594 pdata->ext_cd_cleanup(&sdhci_s3c_notify_change);
596 if (sc->ext_cd_irq)
597 free_irq(sc->ext_cd_irq, sc);
599 if (gpio_is_valid(sc->ext_cd_gpio))
600 gpio_free(sc->ext_cd_gpio);
602 sdhci_remove_host(host, 1);
604 for (ptr = 0; ptr < 3; ptr++) {
605 if (sc->clk_bus[ptr]) {
606 clk_disable(sc->clk_bus[ptr]);
607 clk_put(sc->clk_bus[ptr]);
610 clk_disable(sc->clk_io);
611 clk_put(sc->clk_io);
613 iounmap(host->ioaddr);
614 release_resource(sc->ioarea);
615 kfree(sc->ioarea);
617 sdhci_free_host(host);
618 platform_set_drvdata(pdev, NULL);
620 return 0;
623 #ifdef CONFIG_PM
625 static int sdhci_s3c_suspend(struct device *dev)
627 struct sdhci_host *host = dev_get_drvdata(dev);
629 return sdhci_suspend_host(host);
632 static int sdhci_s3c_resume(struct device *dev)
634 struct sdhci_host *host = dev_get_drvdata(dev);
636 return sdhci_resume_host(host);
639 static const struct dev_pm_ops sdhci_s3c_pmops = {
640 .suspend = sdhci_s3c_suspend,
641 .resume = sdhci_s3c_resume,
644 #define SDHCI_S3C_PMOPS (&sdhci_s3c_pmops)
646 #else
647 #define SDHCI_S3C_PMOPS NULL
648 #endif
650 static struct platform_driver sdhci_s3c_driver = {
651 .probe = sdhci_s3c_probe,
652 .remove = __devexit_p(sdhci_s3c_remove),
653 .driver = {
654 .owner = THIS_MODULE,
655 .name = "s3c-sdhci",
656 .pm = SDHCI_S3C_PMOPS,
660 module_platform_driver(sdhci_s3c_driver);
662 MODULE_DESCRIPTION("Samsung SDHCI (HSMMC) glue");
663 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
664 MODULE_LICENSE("GPL v2");
665 MODULE_ALIAS("platform:s3c-sdhci");