xref: /openbmc/linux/drivers/mmc/host/sdhci-st.c (revision 8730046c)
1 /*
2  * Support for SDHCI on STMicroelectronics SoCs
3  *
4  * Copyright (C) 2014 STMicroelectronics Ltd
5  * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
6  * Contributors: Peter Griffin <peter.griffin@linaro.org>
7  *
8  * Based on sdhci-cns3xxx.c
9  *
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.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  */
20 
21 #include <linux/io.h>
22 #include <linux/of.h>
23 #include <linux/module.h>
24 #include <linux/err.h>
25 #include <linux/mmc/host.h>
26 #include <linux/reset.h>
27 #include "sdhci-pltfm.h"
28 
29 struct st_mmc_platform_data {
30 	struct  reset_control *rstc;
31 	struct  clk *icnclk;
32 	void __iomem *top_ioaddr;
33 };
34 
35 /* MMCSS glue logic to setup the HC on some ST SoCs (e.g. STiH407 family) */
36 
37 #define ST_MMC_CCONFIG_REG_1		0x400
38 #define ST_MMC_CCONFIG_TIMEOUT_CLK_UNIT	BIT(24)
39 #define ST_MMC_CCONFIG_TIMEOUT_CLK_FREQ	BIT(12)
40 #define ST_MMC_CCONFIG_TUNING_COUNT_DEFAULT	BIT(8)
41 #define ST_MMC_CCONFIG_ASYNC_WAKEUP	BIT(0)
42 #define ST_MMC_CCONFIG_1_DEFAULT	\
43 				((ST_MMC_CCONFIG_TIMEOUT_CLK_UNIT) | \
44 				 (ST_MMC_CCONFIG_TIMEOUT_CLK_FREQ) | \
45 				 (ST_MMC_CCONFIG_TUNING_COUNT_DEFAULT))
46 
47 #define ST_MMC_CCONFIG_REG_2		0x404
48 #define ST_MMC_CCONFIG_HIGH_SPEED	BIT(28)
49 #define ST_MMC_CCONFIG_ADMA2		BIT(24)
50 #define ST_MMC_CCONFIG_8BIT		BIT(20)
51 #define ST_MMC_CCONFIG_MAX_BLK_LEN	16
52 #define  MAX_BLK_LEN_1024		1
53 #define  MAX_BLK_LEN_2048		2
54 #define BASE_CLK_FREQ_200		0xc8
55 #define BASE_CLK_FREQ_100		0x64
56 #define BASE_CLK_FREQ_50		0x32
57 #define ST_MMC_CCONFIG_2_DEFAULT \
58 	(ST_MMC_CCONFIG_HIGH_SPEED | ST_MMC_CCONFIG_ADMA2 | \
59 	 ST_MMC_CCONFIG_8BIT | \
60 	 (MAX_BLK_LEN_1024 << ST_MMC_CCONFIG_MAX_BLK_LEN))
61 
62 #define ST_MMC_CCONFIG_REG_3			0x408
63 #define ST_MMC_CCONFIG_EMMC_SLOT_TYPE		BIT(28)
64 #define ST_MMC_CCONFIG_64BIT			BIT(24)
65 #define ST_MMC_CCONFIG_ASYNCH_INTR_SUPPORT	BIT(20)
66 #define ST_MMC_CCONFIG_1P8_VOLT			BIT(16)
67 #define ST_MMC_CCONFIG_3P0_VOLT			BIT(12)
68 #define ST_MMC_CCONFIG_3P3_VOLT			BIT(8)
69 #define ST_MMC_CCONFIG_SUSP_RES_SUPPORT		BIT(4)
70 #define ST_MMC_CCONFIG_SDMA			BIT(0)
71 #define ST_MMC_CCONFIG_3_DEFAULT	\
72 			 (ST_MMC_CCONFIG_ASYNCH_INTR_SUPPORT	| \
73 			  ST_MMC_CCONFIG_3P3_VOLT		| \
74 			  ST_MMC_CCONFIG_SUSP_RES_SUPPORT	| \
75 			  ST_MMC_CCONFIG_SDMA)
76 
77 #define ST_MMC_CCONFIG_REG_4	0x40c
78 #define ST_MMC_CCONFIG_D_DRIVER	BIT(20)
79 #define ST_MMC_CCONFIG_C_DRIVER	BIT(16)
80 #define ST_MMC_CCONFIG_A_DRIVER	BIT(12)
81 #define ST_MMC_CCONFIG_DDR50	BIT(8)
82 #define ST_MMC_CCONFIG_SDR104	BIT(4)
83 #define ST_MMC_CCONFIG_SDR50	BIT(0)
84 #define ST_MMC_CCONFIG_4_DEFAULT	0
85 
86 #define ST_MMC_CCONFIG_REG_5		0x410
87 #define ST_MMC_CCONFIG_TUNING_FOR_SDR50	BIT(8)
88 #define RETUNING_TIMER_CNT_MAX		0xf
89 #define ST_MMC_CCONFIG_5_DEFAULT	0
90 
91 /* I/O configuration for Arasan IP */
92 #define ST_MMC_GP_OUTPUT	0x450
93 #define ST_MMC_GP_OUTPUT_CD	BIT(12)
94 
95 #define ST_MMC_STATUS_R		0x460
96 
97 #define ST_TOP_MMC_DLY_FIX_OFF(x)	(x - 0x8)
98 
99 /* TOP config registers to manage static and dynamic delay */
100 #define ST_TOP_MMC_TX_CLK_DLY			ST_TOP_MMC_DLY_FIX_OFF(0x8)
101 #define ST_TOP_MMC_RX_CLK_DLY			ST_TOP_MMC_DLY_FIX_OFF(0xc)
102 /* MMC delay control register */
103 #define ST_TOP_MMC_DLY_CTRL			ST_TOP_MMC_DLY_FIX_OFF(0x18)
104 #define ST_TOP_MMC_DLY_CTRL_DLL_BYPASS_CMD	BIT(0)
105 #define ST_TOP_MMC_DLY_CTRL_DLL_BYPASS_PH_SEL	BIT(1)
106 #define ST_TOP_MMC_DLY_CTRL_TX_DLL_ENABLE	BIT(8)
107 #define ST_TOP_MMC_DLY_CTRL_RX_DLL_ENABLE	BIT(9)
108 #define ST_TOP_MMC_DLY_CTRL_ATUNE_NOT_CFG_DLY	BIT(10)
109 #define ST_TOP_MMC_START_DLL_LOCK		BIT(11)
110 
111 /* register to provide the phase-shift value for DLL */
112 #define ST_TOP_MMC_TX_DLL_STEP_DLY		ST_TOP_MMC_DLY_FIX_OFF(0x1c)
113 #define ST_TOP_MMC_RX_DLL_STEP_DLY		ST_TOP_MMC_DLY_FIX_OFF(0x20)
114 #define ST_TOP_MMC_RX_CMD_STEP_DLY		ST_TOP_MMC_DLY_FIX_OFF(0x24)
115 
116 /* phase shift delay on the tx clk 2.188ns */
117 #define ST_TOP_MMC_TX_DLL_STEP_DLY_VALID	0x6
118 
119 #define ST_TOP_MMC_DLY_MAX			0xf
120 
121 #define ST_TOP_MMC_DYN_DLY_CONF	\
122 		(ST_TOP_MMC_DLY_CTRL_TX_DLL_ENABLE | \
123 		 ST_TOP_MMC_DLY_CTRL_ATUNE_NOT_CFG_DLY | \
124 		 ST_TOP_MMC_START_DLL_LOCK)
125 
126 /*
127  * For clock speeds greater than 90MHz, we need to check that the
128  * DLL procedure has finished before switching to ultra-speed modes.
129  */
130 #define	CLK_TO_CHECK_DLL_LOCK	90000000
131 
132 static inline void st_mmcss_set_static_delay(void __iomem *ioaddr)
133 {
134 	if (!ioaddr)
135 		return;
136 
137 	writel_relaxed(0x0, ioaddr + ST_TOP_MMC_DLY_CTRL);
138 	writel_relaxed(ST_TOP_MMC_DLY_MAX,
139 			ioaddr + ST_TOP_MMC_TX_CLK_DLY);
140 }
141 
142 /**
143  * st_mmcss_cconfig: configure the Arasan HC inside the flashSS.
144  * @np: dt device node.
145  * @host: sdhci host
146  * Description: this function is to configure the Arasan host controller.
147  * On some ST SoCs, i.e. STiH407 family, the MMC devices inside a dedicated
148  * flashSS sub-system which needs to be configured to be compliant to eMMC 4.5
149  * or eMMC4.3.  This has to be done before registering the sdhci host.
150  */
151 static void st_mmcss_cconfig(struct device_node *np, struct sdhci_host *host)
152 {
153 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
154 	struct mmc_host *mhost = host->mmc;
155 	u32 cconf2, cconf3, cconf4, cconf5;
156 
157 	if (!of_device_is_compatible(np, "st,sdhci-stih407"))
158 		return;
159 
160 	cconf2 = ST_MMC_CCONFIG_2_DEFAULT;
161 	cconf3 = ST_MMC_CCONFIG_3_DEFAULT;
162 	cconf4 = ST_MMC_CCONFIG_4_DEFAULT;
163 	cconf5 = ST_MMC_CCONFIG_5_DEFAULT;
164 
165 	writel_relaxed(ST_MMC_CCONFIG_1_DEFAULT,
166 			host->ioaddr + ST_MMC_CCONFIG_REG_1);
167 
168 	/* Set clock frequency, default to 50MHz if max-frequency is not
169 	 * provided */
170 
171 	switch (mhost->f_max) {
172 	case 200000000:
173 		clk_set_rate(pltfm_host->clk, mhost->f_max);
174 		cconf2 |= BASE_CLK_FREQ_200;
175 		break;
176 	case 100000000:
177 		clk_set_rate(pltfm_host->clk, mhost->f_max);
178 		cconf2 |= BASE_CLK_FREQ_100;
179 		break;
180 	default:
181 		clk_set_rate(pltfm_host->clk, 50000000);
182 		cconf2 |= BASE_CLK_FREQ_50;
183 	}
184 
185 	writel_relaxed(cconf2, host->ioaddr + ST_MMC_CCONFIG_REG_2);
186 
187 	if (!mmc_card_is_removable(mhost))
188 		cconf3 |= ST_MMC_CCONFIG_EMMC_SLOT_TYPE;
189 	else
190 		/* CARD _D ET_CTRL */
191 		writel_relaxed(ST_MMC_GP_OUTPUT_CD,
192 				host->ioaddr + ST_MMC_GP_OUTPUT);
193 
194 	if (mhost->caps & MMC_CAP_UHS_SDR50) {
195 		/* use 1.8V */
196 		cconf3 |= ST_MMC_CCONFIG_1P8_VOLT;
197 		cconf4 |= ST_MMC_CCONFIG_SDR50;
198 		/* Use tuning */
199 		cconf5 |= ST_MMC_CCONFIG_TUNING_FOR_SDR50;
200 		/* Max timeout for retuning */
201 		cconf5 |= RETUNING_TIMER_CNT_MAX;
202 	}
203 
204 	if (mhost->caps & MMC_CAP_UHS_SDR104) {
205 		/*
206 		 * SDR104 implies the HC can support HS200 mode, so
207 		 * it's mandatory to use 1.8V
208 		 */
209 		cconf3 |= ST_MMC_CCONFIG_1P8_VOLT;
210 		cconf4 |= ST_MMC_CCONFIG_SDR104;
211 		/* Max timeout for retuning */
212 		cconf5 |= RETUNING_TIMER_CNT_MAX;
213 	}
214 
215 	if (mhost->caps & MMC_CAP_UHS_DDR50)
216 		cconf4 |= ST_MMC_CCONFIG_DDR50;
217 
218 	writel_relaxed(cconf3, host->ioaddr + ST_MMC_CCONFIG_REG_3);
219 	writel_relaxed(cconf4, host->ioaddr + ST_MMC_CCONFIG_REG_4);
220 	writel_relaxed(cconf5, host->ioaddr + ST_MMC_CCONFIG_REG_5);
221 }
222 
223 static inline void st_mmcss_set_dll(void __iomem *ioaddr)
224 {
225 	if (!ioaddr)
226 		return;
227 
228 	writel_relaxed(ST_TOP_MMC_DYN_DLY_CONF,	ioaddr + ST_TOP_MMC_DLY_CTRL);
229 	writel_relaxed(ST_TOP_MMC_TX_DLL_STEP_DLY_VALID,
230 			ioaddr + ST_TOP_MMC_TX_DLL_STEP_DLY);
231 }
232 
233 static int st_mmcss_lock_dll(void __iomem *ioaddr)
234 {
235 	unsigned long curr, value;
236 	unsigned long finish = jiffies + HZ;
237 
238 	/* Checks if the DLL procedure is finished */
239 	do {
240 		curr = jiffies;
241 		value = readl(ioaddr + ST_MMC_STATUS_R);
242 		if (value & 0x1)
243 			return 0;
244 
245 		cpu_relax();
246 	} while (!time_after_eq(curr, finish));
247 
248 	return -EBUSY;
249 }
250 
251 static int sdhci_st_set_dll_for_clock(struct sdhci_host *host)
252 {
253 	int ret = 0;
254 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
255 	struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
256 
257 	if (host->clock > CLK_TO_CHECK_DLL_LOCK) {
258 		st_mmcss_set_dll(pdata->top_ioaddr);
259 		ret = st_mmcss_lock_dll(host->ioaddr);
260 	}
261 
262 	return ret;
263 }
264 
265 static void sdhci_st_set_uhs_signaling(struct sdhci_host *host,
266 					unsigned int uhs)
267 {
268 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
269 	struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
270 	u16 ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
271 	int ret = 0;
272 
273 	/* Select Bus Speed Mode for host */
274 	ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
275 	switch (uhs) {
276 	/*
277 	 * Set V18_EN -- UHS modes do not work without this.
278 	 * does not change signaling voltage
279 	 */
280 
281 	case MMC_TIMING_UHS_SDR12:
282 		st_mmcss_set_static_delay(pdata->top_ioaddr);
283 		ctrl_2 |= SDHCI_CTRL_UHS_SDR12 | SDHCI_CTRL_VDD_180;
284 		break;
285 	case MMC_TIMING_UHS_SDR25:
286 		st_mmcss_set_static_delay(pdata->top_ioaddr);
287 		ctrl_2 |= SDHCI_CTRL_UHS_SDR25 | SDHCI_CTRL_VDD_180;
288 		break;
289 	case MMC_TIMING_UHS_SDR50:
290 		st_mmcss_set_static_delay(pdata->top_ioaddr);
291 		ctrl_2 |= SDHCI_CTRL_UHS_SDR50 | SDHCI_CTRL_VDD_180;
292 		ret = sdhci_st_set_dll_for_clock(host);
293 		break;
294 	case MMC_TIMING_UHS_SDR104:
295 	case MMC_TIMING_MMC_HS200:
296 		st_mmcss_set_static_delay(pdata->top_ioaddr);
297 		ctrl_2 |= SDHCI_CTRL_UHS_SDR104 | SDHCI_CTRL_VDD_180;
298 		ret =  sdhci_st_set_dll_for_clock(host);
299 		break;
300 	case MMC_TIMING_UHS_DDR50:
301 	case MMC_TIMING_MMC_DDR52:
302 		st_mmcss_set_static_delay(pdata->top_ioaddr);
303 		ctrl_2 |= SDHCI_CTRL_UHS_DDR50 | SDHCI_CTRL_VDD_180;
304 		break;
305 	}
306 
307 	if (ret)
308 		dev_warn(mmc_dev(host->mmc), "Error setting dll for clock "
309 						"(uhs %d)\n", uhs);
310 
311 	dev_dbg(mmc_dev(host->mmc), "uhs %d, ctrl_2 %04X\n", uhs, ctrl_2);
312 
313 	sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
314 }
315 
316 static u32 sdhci_st_readl(struct sdhci_host *host, int reg)
317 {
318 	u32 ret;
319 
320 	switch (reg) {
321 	case SDHCI_CAPABILITIES:
322 		ret = readl_relaxed(host->ioaddr + reg);
323 		/* Support 3.3V and 1.8V */
324 		ret &= ~SDHCI_CAN_VDD_300;
325 		break;
326 	default:
327 		ret = readl_relaxed(host->ioaddr + reg);
328 	}
329 	return ret;
330 }
331 
332 static const struct sdhci_ops sdhci_st_ops = {
333 	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
334 	.set_clock = sdhci_set_clock,
335 	.set_bus_width = sdhci_set_bus_width,
336 	.read_l = sdhci_st_readl,
337 	.reset = sdhci_reset,
338 	.set_uhs_signaling = sdhci_st_set_uhs_signaling,
339 };
340 
341 static const struct sdhci_pltfm_data sdhci_st_pdata = {
342 	.ops = &sdhci_st_ops,
343 	.quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
344 		SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN |
345 		SDHCI_QUIRK_NO_HISPD_BIT,
346 	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
347 		SDHCI_QUIRK2_STOP_WITH_TC,
348 };
349 
350 
351 static int sdhci_st_probe(struct platform_device *pdev)
352 {
353 	struct device_node *np = pdev->dev.of_node;
354 	struct sdhci_host *host;
355 	struct st_mmc_platform_data *pdata;
356 	struct sdhci_pltfm_host *pltfm_host;
357 	struct clk *clk, *icnclk;
358 	int ret = 0;
359 	u16 host_version;
360 	struct resource *res;
361 	struct reset_control *rstc;
362 
363 	clk =  devm_clk_get(&pdev->dev, "mmc");
364 	if (IS_ERR(clk)) {
365 		dev_err(&pdev->dev, "Peripheral clk not found\n");
366 		return PTR_ERR(clk);
367 	}
368 
369 	/* ICN clock isn't compulsory, but use it if it's provided. */
370 	icnclk = devm_clk_get(&pdev->dev, "icn");
371 	if (IS_ERR(icnclk))
372 		icnclk = NULL;
373 
374 	rstc = devm_reset_control_get(&pdev->dev, NULL);
375 	if (IS_ERR(rstc))
376 		rstc = NULL;
377 	else
378 		reset_control_deassert(rstc);
379 
380 	host = sdhci_pltfm_init(pdev, &sdhci_st_pdata, sizeof(*pdata));
381 	if (IS_ERR(host)) {
382 		dev_err(&pdev->dev, "Failed sdhci_pltfm_init\n");
383 		ret = PTR_ERR(host);
384 		goto err_pltfm_init;
385 	}
386 
387 	pltfm_host = sdhci_priv(host);
388 	pdata = sdhci_pltfm_priv(pltfm_host);
389 	pdata->rstc = rstc;
390 
391 	ret = mmc_of_parse(host->mmc);
392 	if (ret) {
393 		dev_err(&pdev->dev, "Failed mmc_of_parse\n");
394 		goto err_of;
395 	}
396 
397 	clk_prepare_enable(clk);
398 	clk_prepare_enable(icnclk);
399 
400 	/* Configure the FlashSS Top registers for setting eMMC TX/RX delay */
401 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
402 					   "top-mmc-delay");
403 	pdata->top_ioaddr = devm_ioremap_resource(&pdev->dev, res);
404 	if (IS_ERR(pdata->top_ioaddr)) {
405 		dev_warn(&pdev->dev, "FlashSS Top Dly registers not available");
406 		pdata->top_ioaddr = NULL;
407 	}
408 
409 	pltfm_host->clk = clk;
410 	pdata->icnclk = icnclk;
411 
412 	/* Configure the Arasan HC inside the flashSS */
413 	st_mmcss_cconfig(np, host);
414 
415 	ret = sdhci_add_host(host);
416 	if (ret) {
417 		dev_err(&pdev->dev, "Failed sdhci_add_host\n");
418 		goto err_out;
419 	}
420 
421 	platform_set_drvdata(pdev, host);
422 
423 	host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION));
424 
425 	dev_info(&pdev->dev, "SDHCI ST Initialised: Host Version: 0x%x Vendor Version 0x%x\n",
426 		((host_version & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT),
427 		((host_version & SDHCI_VENDOR_VER_MASK) >>
428 		SDHCI_VENDOR_VER_SHIFT));
429 
430 	return 0;
431 
432 err_out:
433 	clk_disable_unprepare(icnclk);
434 	clk_disable_unprepare(clk);
435 err_of:
436 	sdhci_pltfm_free(pdev);
437 err_pltfm_init:
438 	if (rstc)
439 		reset_control_assert(rstc);
440 
441 	return ret;
442 }
443 
444 static int sdhci_st_remove(struct platform_device *pdev)
445 {
446 	struct sdhci_host *host = platform_get_drvdata(pdev);
447 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
448 	struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
449 	struct reset_control *rstc = pdata->rstc;
450 	int ret;
451 
452 	ret = sdhci_pltfm_unregister(pdev);
453 
454 	clk_disable_unprepare(pdata->icnclk);
455 
456 	if (rstc)
457 		reset_control_assert(rstc);
458 
459 	return ret;
460 }
461 
462 #ifdef CONFIG_PM_SLEEP
463 static int sdhci_st_suspend(struct device *dev)
464 {
465 	struct sdhci_host *host = dev_get_drvdata(dev);
466 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
467 	struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
468 	int ret = sdhci_suspend_host(host);
469 
470 	if (ret)
471 		goto out;
472 
473 	if (pdata->rstc)
474 		reset_control_assert(pdata->rstc);
475 
476 	clk_disable_unprepare(pdata->icnclk);
477 	clk_disable_unprepare(pltfm_host->clk);
478 out:
479 	return ret;
480 }
481 
482 static int sdhci_st_resume(struct device *dev)
483 {
484 	struct sdhci_host *host = dev_get_drvdata(dev);
485 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
486 	struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
487 	struct device_node *np = dev->of_node;
488 
489 	clk_prepare_enable(pltfm_host->clk);
490 	clk_prepare_enable(pdata->icnclk);
491 
492 	if (pdata->rstc)
493 		reset_control_deassert(pdata->rstc);
494 
495 	st_mmcss_cconfig(np, host);
496 
497 	return sdhci_resume_host(host);
498 }
499 #endif
500 
501 static SIMPLE_DEV_PM_OPS(sdhci_st_pmops, sdhci_st_suspend, sdhci_st_resume);
502 
503 static const struct of_device_id st_sdhci_match[] = {
504 	{ .compatible = "st,sdhci" },
505 	{},
506 };
507 
508 MODULE_DEVICE_TABLE(of, st_sdhci_match);
509 
510 static struct platform_driver sdhci_st_driver = {
511 	.probe = sdhci_st_probe,
512 	.remove = sdhci_st_remove,
513 	.driver = {
514 		   .name = "sdhci-st",
515 		   .pm = &sdhci_st_pmops,
516 		   .of_match_table = of_match_ptr(st_sdhci_match),
517 		  },
518 };
519 
520 module_platform_driver(sdhci_st_driver);
521 
522 MODULE_DESCRIPTION("SDHCI driver for STMicroelectronics SoCs");
523 MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
524 MODULE_LICENSE("GPL v2");
525 MODULE_ALIAS("platform:sdhci-st");
526