xref: /openbmc/linux/drivers/mmc/host/sdhci-msm.c (revision 9718f84b)
1 /*
2  * drivers/mmc/host/sdhci-msm.c - Qualcomm SDHCI Platform driver
3  *
4  * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 and
8  * only version 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/delay.h>
20 #include <linux/mmc/mmc.h>
21 #include <linux/slab.h>
22 
23 #include "sdhci-pltfm.h"
24 
25 #define CORE_MCI_VERSION		0x50
26 #define CORE_VERSION_MAJOR_SHIFT	28
27 #define CORE_VERSION_MAJOR_MASK		(0xf << CORE_VERSION_MAJOR_SHIFT)
28 #define CORE_VERSION_MINOR_MASK		0xff
29 
30 #define CORE_HC_MODE		0x78
31 #define HC_MODE_EN		0x1
32 #define CORE_POWER		0x0
33 #define CORE_SW_RST		BIT(7)
34 
35 #define MAX_PHASES		16
36 #define CORE_DLL_LOCK		BIT(7)
37 #define CORE_DLL_EN		BIT(16)
38 #define CORE_CDR_EN		BIT(17)
39 #define CORE_CK_OUT_EN		BIT(18)
40 #define CORE_CDR_EXT_EN		BIT(19)
41 #define CORE_DLL_PDN		BIT(29)
42 #define CORE_DLL_RST		BIT(30)
43 #define CORE_DLL_CONFIG		0x100
44 #define CORE_DLL_STATUS		0x108
45 
46 #define CORE_VENDOR_SPEC	0x10c
47 #define CORE_CLK_PWRSAVE	BIT(1)
48 
49 #define CORE_VENDOR_SPEC_CAPABILITIES0	0x11c
50 
51 #define CDR_SELEXT_SHIFT	20
52 #define CDR_SELEXT_MASK		(0xf << CDR_SELEXT_SHIFT)
53 #define CMUX_SHIFT_PHASE_SHIFT	24
54 #define CMUX_SHIFT_PHASE_MASK	(7 << CMUX_SHIFT_PHASE_SHIFT)
55 
56 struct sdhci_msm_host {
57 	struct platform_device *pdev;
58 	void __iomem *core_mem;	/* MSM SDCC mapped address */
59 	struct clk *clk;	/* main SD/MMC bus clock */
60 	struct clk *pclk;	/* SDHC peripheral bus clock */
61 	struct clk *bus_clk;	/* SDHC bus voter clock */
62 	struct mmc_host *mmc;
63 };
64 
65 /* Platform specific tuning */
66 static inline int msm_dll_poll_ck_out_en(struct sdhci_host *host, u8 poll)
67 {
68 	u32 wait_cnt = 50;
69 	u8 ck_out_en;
70 	struct mmc_host *mmc = host->mmc;
71 
72 	/* Poll for CK_OUT_EN bit.  max. poll time = 50us */
73 	ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) &
74 			CORE_CK_OUT_EN);
75 
76 	while (ck_out_en != poll) {
77 		if (--wait_cnt == 0) {
78 			dev_err(mmc_dev(mmc), "%s: CK_OUT_EN bit is not %d\n",
79 			       mmc_hostname(mmc), poll);
80 			return -ETIMEDOUT;
81 		}
82 		udelay(1);
83 
84 		ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) &
85 				CORE_CK_OUT_EN);
86 	}
87 
88 	return 0;
89 }
90 
91 static int msm_config_cm_dll_phase(struct sdhci_host *host, u8 phase)
92 {
93 	int rc;
94 	static const u8 grey_coded_phase_table[] = {
95 		0x0, 0x1, 0x3, 0x2, 0x6, 0x7, 0x5, 0x4,
96 		0xc, 0xd, 0xf, 0xe, 0xa, 0xb, 0x9, 0x8
97 	};
98 	unsigned long flags;
99 	u32 config;
100 	struct mmc_host *mmc = host->mmc;
101 
102 	spin_lock_irqsave(&host->lock, flags);
103 
104 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
105 	config &= ~(CORE_CDR_EN | CORE_CK_OUT_EN);
106 	config |= (CORE_CDR_EXT_EN | CORE_DLL_EN);
107 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
108 
109 	/* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '0' */
110 	rc = msm_dll_poll_ck_out_en(host, 0);
111 	if (rc)
112 		goto err_out;
113 
114 	/*
115 	 * Write the selected DLL clock output phase (0 ... 15)
116 	 * to CDR_SELEXT bit field of DLL_CONFIG register.
117 	 */
118 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
119 	config &= ~CDR_SELEXT_MASK;
120 	config |= grey_coded_phase_table[phase] << CDR_SELEXT_SHIFT;
121 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
122 
123 	/* Set CK_OUT_EN bit of DLL_CONFIG register to 1. */
124 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
125 			| CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG);
126 
127 	/* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '1' */
128 	rc = msm_dll_poll_ck_out_en(host, 1);
129 	if (rc)
130 		goto err_out;
131 
132 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
133 	config |= CORE_CDR_EN;
134 	config &= ~CORE_CDR_EXT_EN;
135 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
136 	goto out;
137 
138 err_out:
139 	dev_err(mmc_dev(mmc), "%s: Failed to set DLL phase: %d\n",
140 	       mmc_hostname(mmc), phase);
141 out:
142 	spin_unlock_irqrestore(&host->lock, flags);
143 	return rc;
144 }
145 
146 /*
147  * Find out the greatest range of consecuitive selected
148  * DLL clock output phases that can be used as sampling
149  * setting for SD3.0 UHS-I card read operation (in SDR104
150  * timing mode) or for eMMC4.5 card read operation (in HS200
151  * timing mode).
152  * Select the 3/4 of the range and configure the DLL with the
153  * selected DLL clock output phase.
154  */
155 
156 static int msm_find_most_appropriate_phase(struct sdhci_host *host,
157 					   u8 *phase_table, u8 total_phases)
158 {
159 	int ret;
160 	u8 ranges[MAX_PHASES][MAX_PHASES] = { {0}, {0} };
161 	u8 phases_per_row[MAX_PHASES] = { 0 };
162 	int row_index = 0, col_index = 0, selected_row_index = 0, curr_max = 0;
163 	int i, cnt, phase_0_raw_index = 0, phase_15_raw_index = 0;
164 	bool phase_0_found = false, phase_15_found = false;
165 	struct mmc_host *mmc = host->mmc;
166 
167 	if (!total_phases || (total_phases > MAX_PHASES)) {
168 		dev_err(mmc_dev(mmc), "%s: Invalid argument: total_phases=%d\n",
169 		       mmc_hostname(mmc), total_phases);
170 		return -EINVAL;
171 	}
172 
173 	for (cnt = 0; cnt < total_phases; cnt++) {
174 		ranges[row_index][col_index] = phase_table[cnt];
175 		phases_per_row[row_index] += 1;
176 		col_index++;
177 
178 		if ((cnt + 1) == total_phases) {
179 			continue;
180 		/* check if next phase in phase_table is consecutive or not */
181 		} else if ((phase_table[cnt] + 1) != phase_table[cnt + 1]) {
182 			row_index++;
183 			col_index = 0;
184 		}
185 	}
186 
187 	if (row_index >= MAX_PHASES)
188 		return -EINVAL;
189 
190 	/* Check if phase-0 is present in first valid window? */
191 	if (!ranges[0][0]) {
192 		phase_0_found = true;
193 		phase_0_raw_index = 0;
194 		/* Check if cycle exist between 2 valid windows */
195 		for (cnt = 1; cnt <= row_index; cnt++) {
196 			if (phases_per_row[cnt]) {
197 				for (i = 0; i < phases_per_row[cnt]; i++) {
198 					if (ranges[cnt][i] == 15) {
199 						phase_15_found = true;
200 						phase_15_raw_index = cnt;
201 						break;
202 					}
203 				}
204 			}
205 		}
206 	}
207 
208 	/* If 2 valid windows form cycle then merge them as single window */
209 	if (phase_0_found && phase_15_found) {
210 		/* number of phases in raw where phase 0 is present */
211 		u8 phases_0 = phases_per_row[phase_0_raw_index];
212 		/* number of phases in raw where phase 15 is present */
213 		u8 phases_15 = phases_per_row[phase_15_raw_index];
214 
215 		if (phases_0 + phases_15 >= MAX_PHASES)
216 			/*
217 			 * If there are more than 1 phase windows then total
218 			 * number of phases in both the windows should not be
219 			 * more than or equal to MAX_PHASES.
220 			 */
221 			return -EINVAL;
222 
223 		/* Merge 2 cyclic windows */
224 		i = phases_15;
225 		for (cnt = 0; cnt < phases_0; cnt++) {
226 			ranges[phase_15_raw_index][i] =
227 			    ranges[phase_0_raw_index][cnt];
228 			if (++i >= MAX_PHASES)
229 				break;
230 		}
231 
232 		phases_per_row[phase_0_raw_index] = 0;
233 		phases_per_row[phase_15_raw_index] = phases_15 + phases_0;
234 	}
235 
236 	for (cnt = 0; cnt <= row_index; cnt++) {
237 		if (phases_per_row[cnt] > curr_max) {
238 			curr_max = phases_per_row[cnt];
239 			selected_row_index = cnt;
240 		}
241 	}
242 
243 	i = (curr_max * 3) / 4;
244 	if (i)
245 		i--;
246 
247 	ret = ranges[selected_row_index][i];
248 
249 	if (ret >= MAX_PHASES) {
250 		ret = -EINVAL;
251 		dev_err(mmc_dev(mmc), "%s: Invalid phase selected=%d\n",
252 		       mmc_hostname(mmc), ret);
253 	}
254 
255 	return ret;
256 }
257 
258 static inline void msm_cm_dll_set_freq(struct sdhci_host *host)
259 {
260 	u32 mclk_freq = 0, config;
261 
262 	/* Program the MCLK value to MCLK_FREQ bit field */
263 	if (host->clock <= 112000000)
264 		mclk_freq = 0;
265 	else if (host->clock <= 125000000)
266 		mclk_freq = 1;
267 	else if (host->clock <= 137000000)
268 		mclk_freq = 2;
269 	else if (host->clock <= 150000000)
270 		mclk_freq = 3;
271 	else if (host->clock <= 162000000)
272 		mclk_freq = 4;
273 	else if (host->clock <= 175000000)
274 		mclk_freq = 5;
275 	else if (host->clock <= 187000000)
276 		mclk_freq = 6;
277 	else if (host->clock <= 200000000)
278 		mclk_freq = 7;
279 
280 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
281 	config &= ~CMUX_SHIFT_PHASE_MASK;
282 	config |= mclk_freq << CMUX_SHIFT_PHASE_SHIFT;
283 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
284 }
285 
286 /* Initialize the DLL (Programmable Delay Line) */
287 static int msm_init_cm_dll(struct sdhci_host *host)
288 {
289 	struct mmc_host *mmc = host->mmc;
290 	int wait_cnt = 50;
291 	unsigned long flags;
292 
293 	spin_lock_irqsave(&host->lock, flags);
294 
295 	/*
296 	 * Make sure that clock is always enabled when DLL
297 	 * tuning is in progress. Keeping PWRSAVE ON may
298 	 * turn off the clock.
299 	 */
300 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC)
301 			& ~CORE_CLK_PWRSAVE), host->ioaddr + CORE_VENDOR_SPEC);
302 
303 	/* Write 1 to DLL_RST bit of DLL_CONFIG register */
304 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
305 			| CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG);
306 
307 	/* Write 1 to DLL_PDN bit of DLL_CONFIG register */
308 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
309 			| CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG);
310 	msm_cm_dll_set_freq(host);
311 
312 	/* Write 0 to DLL_RST bit of DLL_CONFIG register */
313 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
314 			& ~CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG);
315 
316 	/* Write 0 to DLL_PDN bit of DLL_CONFIG register */
317 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
318 			& ~CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG);
319 
320 	/* Set DLL_EN bit to 1. */
321 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
322 			| CORE_DLL_EN), host->ioaddr + CORE_DLL_CONFIG);
323 
324 	/* Set CK_OUT_EN bit to 1. */
325 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
326 			| CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG);
327 
328 	/* Wait until DLL_LOCK bit of DLL_STATUS register becomes '1' */
329 	while (!(readl_relaxed(host->ioaddr + CORE_DLL_STATUS) &
330 		 CORE_DLL_LOCK)) {
331 		/* max. wait for 50us sec for LOCK bit to be set */
332 		if (--wait_cnt == 0) {
333 			dev_err(mmc_dev(mmc), "%s: DLL failed to LOCK\n",
334 			       mmc_hostname(mmc));
335 			spin_unlock_irqrestore(&host->lock, flags);
336 			return -ETIMEDOUT;
337 		}
338 		udelay(1);
339 	}
340 
341 	spin_unlock_irqrestore(&host->lock, flags);
342 	return 0;
343 }
344 
345 static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
346 {
347 	int tuning_seq_cnt = 3;
348 	u8 phase, tuned_phases[16], tuned_phase_cnt = 0;
349 	int rc;
350 	struct mmc_host *mmc = host->mmc;
351 	struct mmc_ios ios = host->mmc->ios;
352 
353 	/*
354 	 * Tuning is required for SDR104, HS200 and HS400 cards and
355 	 * if clock frequency is greater than 100MHz in these modes.
356 	 */
357 	if (host->clock <= 100 * 1000 * 1000 ||
358 	    !((ios.timing == MMC_TIMING_MMC_HS200) ||
359 	      (ios.timing == MMC_TIMING_UHS_SDR104)))
360 		return 0;
361 
362 retry:
363 	/* First of all reset the tuning block */
364 	rc = msm_init_cm_dll(host);
365 	if (rc)
366 		return rc;
367 
368 	phase = 0;
369 	do {
370 		/* Set the phase in delay line hw block */
371 		rc = msm_config_cm_dll_phase(host, phase);
372 		if (rc)
373 			return rc;
374 
375 		rc = mmc_send_tuning(mmc, opcode, NULL);
376 		if (!rc) {
377 			/* Tuning is successful at this tuning point */
378 			tuned_phases[tuned_phase_cnt++] = phase;
379 			dev_dbg(mmc_dev(mmc), "%s: Found good phase = %d\n",
380 				 mmc_hostname(mmc), phase);
381 		}
382 	} while (++phase < ARRAY_SIZE(tuned_phases));
383 
384 	if (tuned_phase_cnt) {
385 		rc = msm_find_most_appropriate_phase(host, tuned_phases,
386 						     tuned_phase_cnt);
387 		if (rc < 0)
388 			return rc;
389 		else
390 			phase = rc;
391 
392 		/*
393 		 * Finally set the selected phase in delay
394 		 * line hw block.
395 		 */
396 		rc = msm_config_cm_dll_phase(host, phase);
397 		if (rc)
398 			return rc;
399 		dev_dbg(mmc_dev(mmc), "%s: Setting the tuning phase to %d\n",
400 			 mmc_hostname(mmc), phase);
401 	} else {
402 		if (--tuning_seq_cnt)
403 			goto retry;
404 		/* Tuning failed */
405 		dev_dbg(mmc_dev(mmc), "%s: No tuning point found\n",
406 		       mmc_hostname(mmc));
407 		rc = -EIO;
408 	}
409 
410 	return rc;
411 }
412 
413 static const struct of_device_id sdhci_msm_dt_match[] = {
414 	{ .compatible = "qcom,sdhci-msm-v4" },
415 	{},
416 };
417 
418 MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
419 
420 static const struct sdhci_ops sdhci_msm_ops = {
421 	.platform_execute_tuning = sdhci_msm_execute_tuning,
422 	.reset = sdhci_reset,
423 	.set_clock = sdhci_set_clock,
424 	.set_bus_width = sdhci_set_bus_width,
425 	.set_uhs_signaling = sdhci_set_uhs_signaling,
426 };
427 
428 static const struct sdhci_pltfm_data sdhci_msm_pdata = {
429 	.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION |
430 		  SDHCI_QUIRK_NO_CARD_NO_RESET |
431 		  SDHCI_QUIRK_SINGLE_POWER_WRITE,
432 	.ops = &sdhci_msm_ops,
433 };
434 
435 static int sdhci_msm_probe(struct platform_device *pdev)
436 {
437 	struct sdhci_host *host;
438 	struct sdhci_pltfm_host *pltfm_host;
439 	struct sdhci_msm_host *msm_host;
440 	struct resource *core_memres;
441 	int ret;
442 	u16 host_version, core_minor;
443 	u32 core_version, caps;
444 	u8 core_major;
445 
446 	host = sdhci_pltfm_init(pdev, &sdhci_msm_pdata, sizeof(*msm_host));
447 	if (IS_ERR(host))
448 		return PTR_ERR(host);
449 
450 	pltfm_host = sdhci_priv(host);
451 	msm_host = sdhci_pltfm_priv(pltfm_host);
452 	msm_host->mmc = host->mmc;
453 	msm_host->pdev = pdev;
454 
455 	ret = mmc_of_parse(host->mmc);
456 	if (ret)
457 		goto pltfm_free;
458 
459 	sdhci_get_of_property(pdev);
460 
461 	/* Setup SDCC bus voter clock. */
462 	msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus");
463 	if (!IS_ERR(msm_host->bus_clk)) {
464 		/* Vote for max. clk rate for max. performance */
465 		ret = clk_set_rate(msm_host->bus_clk, INT_MAX);
466 		if (ret)
467 			goto pltfm_free;
468 		ret = clk_prepare_enable(msm_host->bus_clk);
469 		if (ret)
470 			goto pltfm_free;
471 	}
472 
473 	/* Setup main peripheral bus clock */
474 	msm_host->pclk = devm_clk_get(&pdev->dev, "iface");
475 	if (IS_ERR(msm_host->pclk)) {
476 		ret = PTR_ERR(msm_host->pclk);
477 		dev_err(&pdev->dev, "Peripheral clk setup failed (%d)\n", ret);
478 		goto bus_clk_disable;
479 	}
480 
481 	ret = clk_prepare_enable(msm_host->pclk);
482 	if (ret)
483 		goto bus_clk_disable;
484 
485 	/* Setup SDC MMC clock */
486 	msm_host->clk = devm_clk_get(&pdev->dev, "core");
487 	if (IS_ERR(msm_host->clk)) {
488 		ret = PTR_ERR(msm_host->clk);
489 		dev_err(&pdev->dev, "SDC MMC clk setup failed (%d)\n", ret);
490 		goto pclk_disable;
491 	}
492 
493 	/* Vote for maximum clock rate for maximum performance */
494 	ret = clk_set_rate(msm_host->clk, INT_MAX);
495 	if (ret)
496 		dev_warn(&pdev->dev, "core clock boost failed\n");
497 
498 	ret = clk_prepare_enable(msm_host->clk);
499 	if (ret)
500 		goto pclk_disable;
501 
502 	core_memres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
503 	msm_host->core_mem = devm_ioremap_resource(&pdev->dev, core_memres);
504 
505 	if (IS_ERR(msm_host->core_mem)) {
506 		dev_err(&pdev->dev, "Failed to remap registers\n");
507 		ret = PTR_ERR(msm_host->core_mem);
508 		goto clk_disable;
509 	}
510 
511 	/* Reset the core and Enable SDHC mode */
512 	writel_relaxed(readl_relaxed(msm_host->core_mem + CORE_POWER) |
513 		       CORE_SW_RST, msm_host->core_mem + CORE_POWER);
514 
515 	/* SW reset can take upto 10HCLK + 15MCLK cycles. (min 40us) */
516 	usleep_range(1000, 5000);
517 	if (readl(msm_host->core_mem + CORE_POWER) & CORE_SW_RST) {
518 		dev_err(&pdev->dev, "Stuck in reset\n");
519 		ret = -ETIMEDOUT;
520 		goto clk_disable;
521 	}
522 
523 	/* Set HC_MODE_EN bit in HC_MODE register */
524 	writel_relaxed(HC_MODE_EN, (msm_host->core_mem + CORE_HC_MODE));
525 
526 	host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION));
527 	dev_dbg(&pdev->dev, "Host Version: 0x%x Vendor Version 0x%x\n",
528 		host_version, ((host_version & SDHCI_VENDOR_VER_MASK) >>
529 			       SDHCI_VENDOR_VER_SHIFT));
530 
531 	core_version = readl_relaxed(msm_host->core_mem + CORE_MCI_VERSION);
532 	core_major = (core_version & CORE_VERSION_MAJOR_MASK) >>
533 		      CORE_VERSION_MAJOR_SHIFT;
534 	core_minor = core_version & CORE_VERSION_MINOR_MASK;
535 	dev_dbg(&pdev->dev, "MCI Version: 0x%08x, major: 0x%04x, minor: 0x%02x\n",
536 		core_version, core_major, core_minor);
537 
538 	/*
539 	 * Support for some capabilities is not advertised by newer
540 	 * controller versions and must be explicitly enabled.
541 	 */
542 	if (core_major >= 1 && core_minor != 0x11 && core_minor != 0x12) {
543 		caps = readl_relaxed(host->ioaddr + SDHCI_CAPABILITIES);
544 		caps |= SDHCI_CAN_VDD_300 | SDHCI_CAN_DO_8BIT;
545 		writel_relaxed(caps, host->ioaddr +
546 			       CORE_VENDOR_SPEC_CAPABILITIES0);
547 	}
548 
549 	ret = sdhci_add_host(host);
550 	if (ret)
551 		goto clk_disable;
552 
553 	return 0;
554 
555 clk_disable:
556 	clk_disable_unprepare(msm_host->clk);
557 pclk_disable:
558 	clk_disable_unprepare(msm_host->pclk);
559 bus_clk_disable:
560 	if (!IS_ERR(msm_host->bus_clk))
561 		clk_disable_unprepare(msm_host->bus_clk);
562 pltfm_free:
563 	sdhci_pltfm_free(pdev);
564 	return ret;
565 }
566 
567 static int sdhci_msm_remove(struct platform_device *pdev)
568 {
569 	struct sdhci_host *host = platform_get_drvdata(pdev);
570 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
571 	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
572 	int dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) ==
573 		    0xffffffff);
574 
575 	sdhci_remove_host(host, dead);
576 	clk_disable_unprepare(msm_host->clk);
577 	clk_disable_unprepare(msm_host->pclk);
578 	if (!IS_ERR(msm_host->bus_clk))
579 		clk_disable_unprepare(msm_host->bus_clk);
580 	sdhci_pltfm_free(pdev);
581 	return 0;
582 }
583 
584 static struct platform_driver sdhci_msm_driver = {
585 	.probe = sdhci_msm_probe,
586 	.remove = sdhci_msm_remove,
587 	.driver = {
588 		   .name = "sdhci_msm",
589 		   .of_match_table = sdhci_msm_dt_match,
590 	},
591 };
592 
593 module_platform_driver(sdhci_msm_driver);
594 
595 MODULE_DESCRIPTION("Qualcomm Secure Digital Host Controller Interface driver");
596 MODULE_LICENSE("GPL v2");
597