xref: /openbmc/linux/drivers/mmc/host/sdhci-msm.c (revision eb3fcf00)
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 	struct sdhci_pltfm_data sdhci_msm_pdata;
64 };
65 
66 /* Platform specific tuning */
67 static inline int msm_dll_poll_ck_out_en(struct sdhci_host *host, u8 poll)
68 {
69 	u32 wait_cnt = 50;
70 	u8 ck_out_en;
71 	struct mmc_host *mmc = host->mmc;
72 
73 	/* Poll for CK_OUT_EN bit.  max. poll time = 50us */
74 	ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) &
75 			CORE_CK_OUT_EN);
76 
77 	while (ck_out_en != poll) {
78 		if (--wait_cnt == 0) {
79 			dev_err(mmc_dev(mmc), "%s: CK_OUT_EN bit is not %d\n",
80 			       mmc_hostname(mmc), poll);
81 			return -ETIMEDOUT;
82 		}
83 		udelay(1);
84 
85 		ck_out_en = !!(readl_relaxed(host->ioaddr + CORE_DLL_CONFIG) &
86 				CORE_CK_OUT_EN);
87 	}
88 
89 	return 0;
90 }
91 
92 static int msm_config_cm_dll_phase(struct sdhci_host *host, u8 phase)
93 {
94 	int rc;
95 	static const u8 grey_coded_phase_table[] = {
96 		0x0, 0x1, 0x3, 0x2, 0x6, 0x7, 0x5, 0x4,
97 		0xc, 0xd, 0xf, 0xe, 0xa, 0xb, 0x9, 0x8
98 	};
99 	unsigned long flags;
100 	u32 config;
101 	struct mmc_host *mmc = host->mmc;
102 
103 	spin_lock_irqsave(&host->lock, flags);
104 
105 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
106 	config &= ~(CORE_CDR_EN | CORE_CK_OUT_EN);
107 	config |= (CORE_CDR_EXT_EN | CORE_DLL_EN);
108 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
109 
110 	/* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '0' */
111 	rc = msm_dll_poll_ck_out_en(host, 0);
112 	if (rc)
113 		goto err_out;
114 
115 	/*
116 	 * Write the selected DLL clock output phase (0 ... 15)
117 	 * to CDR_SELEXT bit field of DLL_CONFIG register.
118 	 */
119 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
120 	config &= ~CDR_SELEXT_MASK;
121 	config |= grey_coded_phase_table[phase] << CDR_SELEXT_SHIFT;
122 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
123 
124 	/* Set CK_OUT_EN bit of DLL_CONFIG register to 1. */
125 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
126 			| CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG);
127 
128 	/* Wait until CK_OUT_EN bit of DLL_CONFIG register becomes '1' */
129 	rc = msm_dll_poll_ck_out_en(host, 1);
130 	if (rc)
131 		goto err_out;
132 
133 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
134 	config |= CORE_CDR_EN;
135 	config &= ~CORE_CDR_EXT_EN;
136 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
137 	goto out;
138 
139 err_out:
140 	dev_err(mmc_dev(mmc), "%s: Failed to set DLL phase: %d\n",
141 	       mmc_hostname(mmc), phase);
142 out:
143 	spin_unlock_irqrestore(&host->lock, flags);
144 	return rc;
145 }
146 
147 /*
148  * Find out the greatest range of consecuitive selected
149  * DLL clock output phases that can be used as sampling
150  * setting for SD3.0 UHS-I card read operation (in SDR104
151  * timing mode) or for eMMC4.5 card read operation (in HS200
152  * timing mode).
153  * Select the 3/4 of the range and configure the DLL with the
154  * selected DLL clock output phase.
155  */
156 
157 static int msm_find_most_appropriate_phase(struct sdhci_host *host,
158 					   u8 *phase_table, u8 total_phases)
159 {
160 	int ret;
161 	u8 ranges[MAX_PHASES][MAX_PHASES] = { {0}, {0} };
162 	u8 phases_per_row[MAX_PHASES] = { 0 };
163 	int row_index = 0, col_index = 0, selected_row_index = 0, curr_max = 0;
164 	int i, cnt, phase_0_raw_index = 0, phase_15_raw_index = 0;
165 	bool phase_0_found = false, phase_15_found = false;
166 	struct mmc_host *mmc = host->mmc;
167 
168 	if (!total_phases || (total_phases > MAX_PHASES)) {
169 		dev_err(mmc_dev(mmc), "%s: Invalid argument: total_phases=%d\n",
170 		       mmc_hostname(mmc), total_phases);
171 		return -EINVAL;
172 	}
173 
174 	for (cnt = 0; cnt < total_phases; cnt++) {
175 		ranges[row_index][col_index] = phase_table[cnt];
176 		phases_per_row[row_index] += 1;
177 		col_index++;
178 
179 		if ((cnt + 1) == total_phases) {
180 			continue;
181 		/* check if next phase in phase_table is consecutive or not */
182 		} else if ((phase_table[cnt] + 1) != phase_table[cnt + 1]) {
183 			row_index++;
184 			col_index = 0;
185 		}
186 	}
187 
188 	if (row_index >= MAX_PHASES)
189 		return -EINVAL;
190 
191 	/* Check if phase-0 is present in first valid window? */
192 	if (!ranges[0][0]) {
193 		phase_0_found = true;
194 		phase_0_raw_index = 0;
195 		/* Check if cycle exist between 2 valid windows */
196 		for (cnt = 1; cnt <= row_index; cnt++) {
197 			if (phases_per_row[cnt]) {
198 				for (i = 0; i < phases_per_row[cnt]; i++) {
199 					if (ranges[cnt][i] == 15) {
200 						phase_15_found = true;
201 						phase_15_raw_index = cnt;
202 						break;
203 					}
204 				}
205 			}
206 		}
207 	}
208 
209 	/* If 2 valid windows form cycle then merge them as single window */
210 	if (phase_0_found && phase_15_found) {
211 		/* number of phases in raw where phase 0 is present */
212 		u8 phases_0 = phases_per_row[phase_0_raw_index];
213 		/* number of phases in raw where phase 15 is present */
214 		u8 phases_15 = phases_per_row[phase_15_raw_index];
215 
216 		if (phases_0 + phases_15 >= MAX_PHASES)
217 			/*
218 			 * If there are more than 1 phase windows then total
219 			 * number of phases in both the windows should not be
220 			 * more than or equal to MAX_PHASES.
221 			 */
222 			return -EINVAL;
223 
224 		/* Merge 2 cyclic windows */
225 		i = phases_15;
226 		for (cnt = 0; cnt < phases_0; cnt++) {
227 			ranges[phase_15_raw_index][i] =
228 			    ranges[phase_0_raw_index][cnt];
229 			if (++i >= MAX_PHASES)
230 				break;
231 		}
232 
233 		phases_per_row[phase_0_raw_index] = 0;
234 		phases_per_row[phase_15_raw_index] = phases_15 + phases_0;
235 	}
236 
237 	for (cnt = 0; cnt <= row_index; cnt++) {
238 		if (phases_per_row[cnt] > curr_max) {
239 			curr_max = phases_per_row[cnt];
240 			selected_row_index = cnt;
241 		}
242 	}
243 
244 	i = (curr_max * 3) / 4;
245 	if (i)
246 		i--;
247 
248 	ret = ranges[selected_row_index][i];
249 
250 	if (ret >= MAX_PHASES) {
251 		ret = -EINVAL;
252 		dev_err(mmc_dev(mmc), "%s: Invalid phase selected=%d\n",
253 		       mmc_hostname(mmc), ret);
254 	}
255 
256 	return ret;
257 }
258 
259 static inline void msm_cm_dll_set_freq(struct sdhci_host *host)
260 {
261 	u32 mclk_freq = 0, config;
262 
263 	/* Program the MCLK value to MCLK_FREQ bit field */
264 	if (host->clock <= 112000000)
265 		mclk_freq = 0;
266 	else if (host->clock <= 125000000)
267 		mclk_freq = 1;
268 	else if (host->clock <= 137000000)
269 		mclk_freq = 2;
270 	else if (host->clock <= 150000000)
271 		mclk_freq = 3;
272 	else if (host->clock <= 162000000)
273 		mclk_freq = 4;
274 	else if (host->clock <= 175000000)
275 		mclk_freq = 5;
276 	else if (host->clock <= 187000000)
277 		mclk_freq = 6;
278 	else if (host->clock <= 200000000)
279 		mclk_freq = 7;
280 
281 	config = readl_relaxed(host->ioaddr + CORE_DLL_CONFIG);
282 	config &= ~CMUX_SHIFT_PHASE_MASK;
283 	config |= mclk_freq << CMUX_SHIFT_PHASE_SHIFT;
284 	writel_relaxed(config, host->ioaddr + CORE_DLL_CONFIG);
285 }
286 
287 /* Initialize the DLL (Programmable Delay Line) */
288 static int msm_init_cm_dll(struct sdhci_host *host)
289 {
290 	struct mmc_host *mmc = host->mmc;
291 	int wait_cnt = 50;
292 	unsigned long flags;
293 
294 	spin_lock_irqsave(&host->lock, flags);
295 
296 	/*
297 	 * Make sure that clock is always enabled when DLL
298 	 * tuning is in progress. Keeping PWRSAVE ON may
299 	 * turn off the clock.
300 	 */
301 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_VENDOR_SPEC)
302 			& ~CORE_CLK_PWRSAVE), host->ioaddr + CORE_VENDOR_SPEC);
303 
304 	/* Write 1 to DLL_RST bit of DLL_CONFIG register */
305 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
306 			| CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG);
307 
308 	/* Write 1 to DLL_PDN bit of DLL_CONFIG register */
309 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
310 			| CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG);
311 	msm_cm_dll_set_freq(host);
312 
313 	/* Write 0 to DLL_RST bit of DLL_CONFIG register */
314 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
315 			& ~CORE_DLL_RST), host->ioaddr + CORE_DLL_CONFIG);
316 
317 	/* Write 0 to DLL_PDN bit of DLL_CONFIG register */
318 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
319 			& ~CORE_DLL_PDN), host->ioaddr + CORE_DLL_CONFIG);
320 
321 	/* Set DLL_EN bit to 1. */
322 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
323 			| CORE_DLL_EN), host->ioaddr + CORE_DLL_CONFIG);
324 
325 	/* Set CK_OUT_EN bit to 1. */
326 	writel_relaxed((readl_relaxed(host->ioaddr + CORE_DLL_CONFIG)
327 			| CORE_CK_OUT_EN), host->ioaddr + CORE_DLL_CONFIG);
328 
329 	/* Wait until DLL_LOCK bit of DLL_STATUS register becomes '1' */
330 	while (!(readl_relaxed(host->ioaddr + CORE_DLL_STATUS) &
331 		 CORE_DLL_LOCK)) {
332 		/* max. wait for 50us sec for LOCK bit to be set */
333 		if (--wait_cnt == 0) {
334 			dev_err(mmc_dev(mmc), "%s: DLL failed to LOCK\n",
335 			       mmc_hostname(mmc));
336 			spin_unlock_irqrestore(&host->lock, flags);
337 			return -ETIMEDOUT;
338 		}
339 		udelay(1);
340 	}
341 
342 	spin_unlock_irqrestore(&host->lock, flags);
343 	return 0;
344 }
345 
346 static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
347 {
348 	int tuning_seq_cnt = 3;
349 	u8 phase, tuned_phases[16], tuned_phase_cnt = 0;
350 	int rc;
351 	struct mmc_host *mmc = host->mmc;
352 	struct mmc_ios ios = host->mmc->ios;
353 
354 	/*
355 	 * Tuning is required for SDR104, HS200 and HS400 cards and
356 	 * if clock frequency is greater than 100MHz in these modes.
357 	 */
358 	if (host->clock <= 100 * 1000 * 1000 ||
359 	    !((ios.timing == MMC_TIMING_MMC_HS200) ||
360 	      (ios.timing == MMC_TIMING_UHS_SDR104)))
361 		return 0;
362 
363 retry:
364 	/* First of all reset the tuning block */
365 	rc = msm_init_cm_dll(host);
366 	if (rc)
367 		return rc;
368 
369 	phase = 0;
370 	do {
371 		/* Set the phase in delay line hw block */
372 		rc = msm_config_cm_dll_phase(host, phase);
373 		if (rc)
374 			return rc;
375 
376 		rc = mmc_send_tuning(mmc);
377 		if (!rc) {
378 			/* Tuning is successful at this tuning point */
379 			tuned_phases[tuned_phase_cnt++] = phase;
380 			dev_dbg(mmc_dev(mmc), "%s: Found good phase = %d\n",
381 				 mmc_hostname(mmc), phase);
382 		}
383 	} while (++phase < ARRAY_SIZE(tuned_phases));
384 
385 	if (tuned_phase_cnt) {
386 		rc = msm_find_most_appropriate_phase(host, tuned_phases,
387 						     tuned_phase_cnt);
388 		if (rc < 0)
389 			return rc;
390 		else
391 			phase = rc;
392 
393 		/*
394 		 * Finally set the selected phase in delay
395 		 * line hw block.
396 		 */
397 		rc = msm_config_cm_dll_phase(host, phase);
398 		if (rc)
399 			return rc;
400 		dev_dbg(mmc_dev(mmc), "%s: Setting the tuning phase to %d\n",
401 			 mmc_hostname(mmc), phase);
402 	} else {
403 		if (--tuning_seq_cnt)
404 			goto retry;
405 		/* Tuning failed */
406 		dev_dbg(mmc_dev(mmc), "%s: No tuning point found\n",
407 		       mmc_hostname(mmc));
408 		rc = -EIO;
409 	}
410 
411 	return rc;
412 }
413 
414 static const struct of_device_id sdhci_msm_dt_match[] = {
415 	{ .compatible = "qcom,sdhci-msm-v4" },
416 	{},
417 };
418 
419 MODULE_DEVICE_TABLE(of, sdhci_msm_dt_match);
420 
421 static struct sdhci_ops sdhci_msm_ops = {
422 	.platform_execute_tuning = sdhci_msm_execute_tuning,
423 	.reset = sdhci_reset,
424 	.set_clock = sdhci_set_clock,
425 	.set_bus_width = sdhci_set_bus_width,
426 	.set_uhs_signaling = sdhci_set_uhs_signaling,
427 };
428 
429 static int sdhci_msm_probe(struct platform_device *pdev)
430 {
431 	struct sdhci_host *host;
432 	struct sdhci_pltfm_host *pltfm_host;
433 	struct sdhci_msm_host *msm_host;
434 	struct resource *core_memres;
435 	int ret;
436 	u16 host_version, core_minor;
437 	u32 core_version, caps;
438 	u8 core_major;
439 
440 	msm_host = devm_kzalloc(&pdev->dev, sizeof(*msm_host), GFP_KERNEL);
441 	if (!msm_host)
442 		return -ENOMEM;
443 
444 	msm_host->sdhci_msm_pdata.ops = &sdhci_msm_ops;
445 	host = sdhci_pltfm_init(pdev, &msm_host->sdhci_msm_pdata, 0);
446 	if (IS_ERR(host))
447 		return PTR_ERR(host);
448 
449 	pltfm_host = sdhci_priv(host);
450 	pltfm_host->priv = msm_host;
451 	msm_host->mmc = host->mmc;
452 	msm_host->pdev = pdev;
453 
454 	ret = mmc_of_parse(host->mmc);
455 	if (ret)
456 		goto pltfm_free;
457 
458 	sdhci_get_of_property(pdev);
459 
460 	/* Setup SDCC bus voter clock. */
461 	msm_host->bus_clk = devm_clk_get(&pdev->dev, "bus");
462 	if (!IS_ERR(msm_host->bus_clk)) {
463 		/* Vote for max. clk rate for max. performance */
464 		ret = clk_set_rate(msm_host->bus_clk, INT_MAX);
465 		if (ret)
466 			goto pltfm_free;
467 		ret = clk_prepare_enable(msm_host->bus_clk);
468 		if (ret)
469 			goto pltfm_free;
470 	}
471 
472 	/* Setup main peripheral bus clock */
473 	msm_host->pclk = devm_clk_get(&pdev->dev, "iface");
474 	if (IS_ERR(msm_host->pclk)) {
475 		ret = PTR_ERR(msm_host->pclk);
476 		dev_err(&pdev->dev, "Perpheral clk setup failed (%d)\n", ret);
477 		goto bus_clk_disable;
478 	}
479 
480 	ret = clk_prepare_enable(msm_host->pclk);
481 	if (ret)
482 		goto bus_clk_disable;
483 
484 	/* Setup SDC MMC clock */
485 	msm_host->clk = devm_clk_get(&pdev->dev, "core");
486 	if (IS_ERR(msm_host->clk)) {
487 		ret = PTR_ERR(msm_host->clk);
488 		dev_err(&pdev->dev, "SDC MMC clk setup failed (%d)\n", ret);
489 		goto pclk_disable;
490 	}
491 
492 	/* Vote for maximum clock rate for maximum performance */
493 	ret = clk_set_rate(msm_host->clk, INT_MAX);
494 	if (ret)
495 		dev_warn(&pdev->dev, "core clock boost failed\n");
496 
497 	ret = clk_prepare_enable(msm_host->clk);
498 	if (ret)
499 		goto pclk_disable;
500 
501 	core_memres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
502 	msm_host->core_mem = devm_ioremap_resource(&pdev->dev, core_memres);
503 
504 	if (IS_ERR(msm_host->core_mem)) {
505 		dev_err(&pdev->dev, "Failed to remap registers\n");
506 		ret = PTR_ERR(msm_host->core_mem);
507 		goto clk_disable;
508 	}
509 
510 	/* Reset the core and Enable SDHC mode */
511 	writel_relaxed(readl_relaxed(msm_host->core_mem + CORE_POWER) |
512 		       CORE_SW_RST, msm_host->core_mem + CORE_POWER);
513 
514 	/* SW reset can take upto 10HCLK + 15MCLK cycles. (min 40us) */
515 	usleep_range(1000, 5000);
516 	if (readl(msm_host->core_mem + CORE_POWER) & CORE_SW_RST) {
517 		dev_err(&pdev->dev, "Stuck in reset\n");
518 		ret = -ETIMEDOUT;
519 		goto clk_disable;
520 	}
521 
522 	/* Set HC_MODE_EN bit in HC_MODE register */
523 	writel_relaxed(HC_MODE_EN, (msm_host->core_mem + CORE_HC_MODE));
524 
525 	host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;
526 	host->quirks |= SDHCI_QUIRK_SINGLE_POWER_WRITE;
527 
528 	host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION));
529 	dev_dbg(&pdev->dev, "Host Version: 0x%x Vendor Version 0x%x\n",
530 		host_version, ((host_version & SDHCI_VENDOR_VER_MASK) >>
531 			       SDHCI_VENDOR_VER_SHIFT));
532 
533 	core_version = readl_relaxed(msm_host->core_mem + CORE_MCI_VERSION);
534 	core_major = (core_version & CORE_VERSION_MAJOR_MASK) >>
535 		      CORE_VERSION_MAJOR_SHIFT;
536 	core_minor = core_version & CORE_VERSION_MINOR_MASK;
537 	dev_dbg(&pdev->dev, "MCI Version: 0x%08x, major: 0x%04x, minor: 0x%02x\n",
538 		core_version, core_major, core_minor);
539 
540 	/*
541 	 * Support for some capabilities is not advertised by newer
542 	 * controller versions and must be explicitly enabled.
543 	 */
544 	if (core_major >= 1 && core_minor != 0x11 && core_minor != 0x12) {
545 		caps = readl_relaxed(host->ioaddr + SDHCI_CAPABILITIES);
546 		caps |= SDHCI_CAN_VDD_300 | SDHCI_CAN_DO_8BIT;
547 		writel_relaxed(caps, host->ioaddr +
548 			       CORE_VENDOR_SPEC_CAPABILITIES0);
549 	}
550 
551 	ret = sdhci_add_host(host);
552 	if (ret)
553 		goto clk_disable;
554 
555 	return 0;
556 
557 clk_disable:
558 	clk_disable_unprepare(msm_host->clk);
559 pclk_disable:
560 	clk_disable_unprepare(msm_host->pclk);
561 bus_clk_disable:
562 	if (!IS_ERR(msm_host->bus_clk))
563 		clk_disable_unprepare(msm_host->bus_clk);
564 pltfm_free:
565 	sdhci_pltfm_free(pdev);
566 	return ret;
567 }
568 
569 static int sdhci_msm_remove(struct platform_device *pdev)
570 {
571 	struct sdhci_host *host = platform_get_drvdata(pdev);
572 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
573 	struct sdhci_msm_host *msm_host = pltfm_host->priv;
574 	int dead = (readl_relaxed(host->ioaddr + SDHCI_INT_STATUS) ==
575 		    0xffffffff);
576 
577 	sdhci_remove_host(host, dead);
578 	sdhci_pltfm_free(pdev);
579 	clk_disable_unprepare(msm_host->clk);
580 	clk_disable_unprepare(msm_host->pclk);
581 	if (!IS_ERR(msm_host->bus_clk))
582 		clk_disable_unprepare(msm_host->bus_clk);
583 	return 0;
584 }
585 
586 static struct platform_driver sdhci_msm_driver = {
587 	.probe = sdhci_msm_probe,
588 	.remove = sdhci_msm_remove,
589 	.driver = {
590 		   .name = "sdhci_msm",
591 		   .of_match_table = sdhci_msm_dt_match,
592 	},
593 };
594 
595 module_platform_driver(sdhci_msm_driver);
596 
597 MODULE_DESCRIPTION("Qualcomm Secure Digital Host Controller Interface driver");
598 MODULE_LICENSE("GPL v2");
599