xref: /openbmc/linux/drivers/mmc/host/uniphier-sd.c (revision 0eb76ba2)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2017-2018 Socionext Inc.
4 //   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
5 
6 #include <linux/bitfield.h>
7 #include <linux/bitops.h>
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/mfd/tmio.h>
12 #include <linux/mmc/host.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/platform_device.h>
18 #include <linux/reset.h>
19 
20 #include "tmio_mmc.h"
21 
22 #define   UNIPHIER_SD_CLK_CTL_DIV1024		BIT(16)
23 #define   UNIPHIER_SD_CLK_CTL_DIV1		BIT(10)
24 #define   UNIPHIER_SD_CLKCTL_OFFEN		BIT(9)  // auto SDCLK stop
25 #define UNIPHIER_SD_CC_EXT_MODE		0x1b0
26 #define   UNIPHIER_SD_CC_EXT_MODE_DMA		BIT(1)
27 #define UNIPHIER_SD_HOST_MODE		0x1c8
28 #define UNIPHIER_SD_VOLT		0x1e4
29 #define   UNIPHIER_SD_VOLT_MASK			GENMASK(1, 0)
30 #define   UNIPHIER_SD_VOLT_OFF			0
31 #define   UNIPHIER_SD_VOLT_330			1	// 3.3V signal
32 #define   UNIPHIER_SD_VOLT_180			2	// 1.8V signal
33 #define UNIPHIER_SD_DMA_MODE		0x410
34 #define   UNIPHIER_SD_DMA_MODE_DIR_MASK		GENMASK(17, 16)
35 #define   UNIPHIER_SD_DMA_MODE_DIR_TO_DEV	0
36 #define   UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV	1
37 #define   UNIPHIER_SD_DMA_MODE_WIDTH_MASK	GENMASK(5, 4)
38 #define   UNIPHIER_SD_DMA_MODE_WIDTH_8		0
39 #define   UNIPHIER_SD_DMA_MODE_WIDTH_16		1
40 #define   UNIPHIER_SD_DMA_MODE_WIDTH_32		2
41 #define   UNIPHIER_SD_DMA_MODE_WIDTH_64		3
42 #define   UNIPHIER_SD_DMA_MODE_ADDR_INC		BIT(0)	// 1: inc, 0: fixed
43 #define UNIPHIER_SD_DMA_CTL		0x414
44 #define   UNIPHIER_SD_DMA_CTL_START	BIT(0)	// start DMA (auto cleared)
45 #define UNIPHIER_SD_DMA_RST		0x418
46 #define   UNIPHIER_SD_DMA_RST_CH1	BIT(9)
47 #define   UNIPHIER_SD_DMA_RST_CH0	BIT(8)
48 #define UNIPHIER_SD_DMA_ADDR_L		0x440
49 #define UNIPHIER_SD_DMA_ADDR_H		0x444
50 
51 /*
52  * IP is extended to support various features: built-in DMA engine,
53  * 1/1024 divisor, etc.
54  */
55 #define UNIPHIER_SD_CAP_EXTENDED_IP		BIT(0)
56 /* RX channel of the built-in DMA controller is broken (Pro5) */
57 #define UNIPHIER_SD_CAP_BROKEN_DMA_RX		BIT(1)
58 
59 struct uniphier_sd_priv {
60 	struct tmio_mmc_data tmio_data;
61 	struct pinctrl *pinctrl;
62 	struct pinctrl_state *pinstate_uhs;
63 	struct clk *clk;
64 	struct reset_control *rst;
65 	struct reset_control *rst_br;
66 	struct reset_control *rst_hw;
67 	struct dma_chan *chan;
68 	enum dma_data_direction dma_dir;
69 	unsigned long clk_rate;
70 	unsigned long caps;
71 };
72 
73 static void *uniphier_sd_priv(struct tmio_mmc_host *host)
74 {
75 	return container_of(host->pdata, struct uniphier_sd_priv, tmio_data);
76 }
77 
78 static void uniphier_sd_dma_endisable(struct tmio_mmc_host *host, int enable)
79 {
80 	sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
81 }
82 
83 /* external DMA engine */
84 static void uniphier_sd_external_dma_issue(unsigned long arg)
85 {
86 	struct tmio_mmc_host *host = (void *)arg;
87 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
88 
89 	uniphier_sd_dma_endisable(host, 1);
90 	dma_async_issue_pending(priv->chan);
91 }
92 
93 static void uniphier_sd_external_dma_callback(void *param,
94 					const struct dmaengine_result *result)
95 {
96 	struct tmio_mmc_host *host = param;
97 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
98 	unsigned long flags;
99 
100 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
101 		     priv->dma_dir);
102 
103 	spin_lock_irqsave(&host->lock, flags);
104 
105 	if (result->result == DMA_TRANS_NOERROR) {
106 		/*
107 		 * When the external DMA engine is enabled, strangely enough,
108 		 * the DATAEND flag can be asserted even if the DMA engine has
109 		 * not been kicked yet.  Enable the TMIO_STAT_DATAEND irq only
110 		 * after we make sure the DMA engine finishes the transfer,
111 		 * hence, in this callback.
112 		 */
113 		tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
114 	} else {
115 		host->data->error = -ETIMEDOUT;
116 		tmio_mmc_do_data_irq(host);
117 	}
118 
119 	spin_unlock_irqrestore(&host->lock, flags);
120 }
121 
122 static void uniphier_sd_external_dma_start(struct tmio_mmc_host *host,
123 					   struct mmc_data *data)
124 {
125 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
126 	enum dma_transfer_direction dma_tx_dir;
127 	struct dma_async_tx_descriptor *desc;
128 	dma_cookie_t cookie;
129 	int sg_len;
130 
131 	if (!priv->chan)
132 		goto force_pio;
133 
134 	if (data->flags & MMC_DATA_READ) {
135 		priv->dma_dir = DMA_FROM_DEVICE;
136 		dma_tx_dir = DMA_DEV_TO_MEM;
137 	} else {
138 		priv->dma_dir = DMA_TO_DEVICE;
139 		dma_tx_dir = DMA_MEM_TO_DEV;
140 	}
141 
142 	sg_len = dma_map_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
143 			    priv->dma_dir);
144 	if (sg_len == 0)
145 		goto force_pio;
146 
147 	desc = dmaengine_prep_slave_sg(priv->chan, host->sg_ptr, sg_len,
148 				       dma_tx_dir, DMA_CTRL_ACK);
149 	if (!desc)
150 		goto unmap_sg;
151 
152 	desc->callback_result = uniphier_sd_external_dma_callback;
153 	desc->callback_param = host;
154 
155 	cookie = dmaengine_submit(desc);
156 	if (cookie < 0)
157 		goto unmap_sg;
158 
159 	host->dma_on = true;
160 
161 	return;
162 
163 unmap_sg:
164 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
165 		     priv->dma_dir);
166 force_pio:
167 	uniphier_sd_dma_endisable(host, 0);
168 }
169 
170 static void uniphier_sd_external_dma_enable(struct tmio_mmc_host *host,
171 					    bool enable)
172 {
173 }
174 
175 static void uniphier_sd_external_dma_request(struct tmio_mmc_host *host,
176 					     struct tmio_mmc_data *pdata)
177 {
178 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
179 	struct dma_chan *chan;
180 
181 	chan = dma_request_chan(mmc_dev(host->mmc), "rx-tx");
182 	if (IS_ERR(chan)) {
183 		dev_warn(mmc_dev(host->mmc),
184 			 "failed to request DMA channel. falling back to PIO\n");
185 		return;	/* just use PIO even for -EPROBE_DEFER */
186 	}
187 
188 	/* this driver uses a single channel for both RX an TX */
189 	priv->chan = chan;
190 	host->chan_rx = chan;
191 	host->chan_tx = chan;
192 
193 	tasklet_init(&host->dma_issue, uniphier_sd_external_dma_issue,
194 		     (unsigned long)host);
195 }
196 
197 static void uniphier_sd_external_dma_release(struct tmio_mmc_host *host)
198 {
199 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
200 
201 	if (priv->chan)
202 		dma_release_channel(priv->chan);
203 }
204 
205 static void uniphier_sd_external_dma_abort(struct tmio_mmc_host *host)
206 {
207 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
208 
209 	uniphier_sd_dma_endisable(host, 0);
210 
211 	if (priv->chan)
212 		dmaengine_terminate_sync(priv->chan);
213 }
214 
215 static void uniphier_sd_external_dma_dataend(struct tmio_mmc_host *host)
216 {
217 	uniphier_sd_dma_endisable(host, 0);
218 
219 	tmio_mmc_do_data_irq(host);
220 }
221 
222 static const struct tmio_mmc_dma_ops uniphier_sd_external_dma_ops = {
223 	.start = uniphier_sd_external_dma_start,
224 	.enable = uniphier_sd_external_dma_enable,
225 	.request = uniphier_sd_external_dma_request,
226 	.release = uniphier_sd_external_dma_release,
227 	.abort = uniphier_sd_external_dma_abort,
228 	.dataend = uniphier_sd_external_dma_dataend,
229 };
230 
231 static void uniphier_sd_internal_dma_issue(unsigned long arg)
232 {
233 	struct tmio_mmc_host *host = (void *)arg;
234 	unsigned long flags;
235 
236 	spin_lock_irqsave(&host->lock, flags);
237 	tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
238 	spin_unlock_irqrestore(&host->lock, flags);
239 
240 	uniphier_sd_dma_endisable(host, 1);
241 	writel(UNIPHIER_SD_DMA_CTL_START, host->ctl + UNIPHIER_SD_DMA_CTL);
242 }
243 
244 static void uniphier_sd_internal_dma_start(struct tmio_mmc_host *host,
245 					   struct mmc_data *data)
246 {
247 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
248 	struct scatterlist *sg = host->sg_ptr;
249 	dma_addr_t dma_addr;
250 	unsigned int dma_mode_dir;
251 	u32 dma_mode;
252 	int sg_len;
253 
254 	if ((data->flags & MMC_DATA_READ) && !host->chan_rx)
255 		goto force_pio;
256 
257 	if (WARN_ON(host->sg_len != 1))
258 		goto force_pio;
259 
260 	if (!IS_ALIGNED(sg->offset, 8))
261 		goto force_pio;
262 
263 	if (data->flags & MMC_DATA_READ) {
264 		priv->dma_dir = DMA_FROM_DEVICE;
265 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV;
266 	} else {
267 		priv->dma_dir = DMA_TO_DEVICE;
268 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_TO_DEV;
269 	}
270 
271 	sg_len = dma_map_sg(mmc_dev(host->mmc), sg, 1, priv->dma_dir);
272 	if (sg_len == 0)
273 		goto force_pio;
274 
275 	dma_mode = FIELD_PREP(UNIPHIER_SD_DMA_MODE_DIR_MASK, dma_mode_dir);
276 	dma_mode |= FIELD_PREP(UNIPHIER_SD_DMA_MODE_WIDTH_MASK,
277 			       UNIPHIER_SD_DMA_MODE_WIDTH_64);
278 	dma_mode |= UNIPHIER_SD_DMA_MODE_ADDR_INC;
279 
280 	writel(dma_mode, host->ctl + UNIPHIER_SD_DMA_MODE);
281 
282 	dma_addr = sg_dma_address(data->sg);
283 	writel(lower_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_L);
284 	writel(upper_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_H);
285 
286 	host->dma_on = true;
287 
288 	return;
289 force_pio:
290 	uniphier_sd_dma_endisable(host, 0);
291 }
292 
293 static void uniphier_sd_internal_dma_enable(struct tmio_mmc_host *host,
294 					    bool enable)
295 {
296 }
297 
298 static void uniphier_sd_internal_dma_request(struct tmio_mmc_host *host,
299 					     struct tmio_mmc_data *pdata)
300 {
301 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
302 
303 	/*
304 	 * Due to a hardware bug, Pro5 cannot use DMA for RX.
305 	 * We can still use DMA for TX, but PIO for RX.
306 	 */
307 	if (!(priv->caps & UNIPHIER_SD_CAP_BROKEN_DMA_RX))
308 		host->chan_rx = (void *)0xdeadbeaf;
309 
310 	host->chan_tx = (void *)0xdeadbeaf;
311 
312 	tasklet_init(&host->dma_issue, uniphier_sd_internal_dma_issue,
313 		     (unsigned long)host);
314 }
315 
316 static void uniphier_sd_internal_dma_release(struct tmio_mmc_host *host)
317 {
318 	/* Each value is set to zero to assume "disabling" each DMA */
319 	host->chan_rx = NULL;
320 	host->chan_tx = NULL;
321 }
322 
323 static void uniphier_sd_internal_dma_abort(struct tmio_mmc_host *host)
324 {
325 	u32 tmp;
326 
327 	uniphier_sd_dma_endisable(host, 0);
328 
329 	tmp = readl(host->ctl + UNIPHIER_SD_DMA_RST);
330 	tmp &= ~(UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0);
331 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
332 
333 	tmp |= UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0;
334 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
335 }
336 
337 static void uniphier_sd_internal_dma_dataend(struct tmio_mmc_host *host)
338 {
339 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
340 
341 	uniphier_sd_dma_endisable(host, 0);
342 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, 1, priv->dma_dir);
343 
344 	tmio_mmc_do_data_irq(host);
345 }
346 
347 static const struct tmio_mmc_dma_ops uniphier_sd_internal_dma_ops = {
348 	.start = uniphier_sd_internal_dma_start,
349 	.enable = uniphier_sd_internal_dma_enable,
350 	.request = uniphier_sd_internal_dma_request,
351 	.release = uniphier_sd_internal_dma_release,
352 	.abort = uniphier_sd_internal_dma_abort,
353 	.dataend = uniphier_sd_internal_dma_dataend,
354 };
355 
356 static int uniphier_sd_clk_enable(struct tmio_mmc_host *host)
357 {
358 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
359 	struct mmc_host *mmc = host->mmc;
360 	int ret;
361 
362 	ret = clk_prepare_enable(priv->clk);
363 	if (ret)
364 		return ret;
365 
366 	ret = clk_set_rate(priv->clk, ULONG_MAX);
367 	if (ret)
368 		goto disable_clk;
369 
370 	priv->clk_rate = clk_get_rate(priv->clk);
371 
372 	/* If max-frequency property is set, use it. */
373 	if (!mmc->f_max)
374 		mmc->f_max = priv->clk_rate;
375 
376 	/*
377 	 * 1/512 is the finest divisor in the original IP.  Newer versions
378 	 * also supports 1/1024 divisor. (UniPhier-specific extension)
379 	 */
380 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
381 		mmc->f_min = priv->clk_rate / 1024;
382 	else
383 		mmc->f_min = priv->clk_rate / 512;
384 
385 	ret = reset_control_deassert(priv->rst);
386 	if (ret)
387 		goto disable_clk;
388 
389 	ret = reset_control_deassert(priv->rst_br);
390 	if (ret)
391 		goto assert_rst;
392 
393 	return 0;
394 
395 assert_rst:
396 	reset_control_assert(priv->rst);
397 disable_clk:
398 	clk_disable_unprepare(priv->clk);
399 
400 	return ret;
401 }
402 
403 static void uniphier_sd_clk_disable(struct tmio_mmc_host *host)
404 {
405 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
406 
407 	reset_control_assert(priv->rst_br);
408 	reset_control_assert(priv->rst);
409 	clk_disable_unprepare(priv->clk);
410 }
411 
412 static void uniphier_sd_hw_reset(struct mmc_host *mmc)
413 {
414 	struct tmio_mmc_host *host = mmc_priv(mmc);
415 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
416 
417 	reset_control_assert(priv->rst_hw);
418 	/* For eMMC, minimum is 1us but give it 9us for good measure */
419 	udelay(9);
420 	reset_control_deassert(priv->rst_hw);
421 	/* For eMMC, minimum is 200us but give it 300us for good measure */
422 	usleep_range(300, 1000);
423 }
424 
425 static void uniphier_sd_set_clock(struct tmio_mmc_host *host,
426 				  unsigned int clock)
427 {
428 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
429 	unsigned long divisor;
430 	u32 tmp;
431 
432 	tmp = readl(host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
433 
434 	/* stop the clock before changing its rate to avoid a glitch signal */
435 	tmp &= ~CLK_CTL_SCLKEN;
436 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
437 
438 	if (clock == 0)
439 		return;
440 
441 	tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1024;
442 	tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1;
443 	tmp &= ~CLK_CTL_DIV_MASK;
444 
445 	divisor = priv->clk_rate / clock;
446 
447 	/*
448 	 * In the original IP, bit[7:0] represents the divisor.
449 	 * bit7 set: 1/512, ... bit0 set:1/4, all bits clear: 1/2
450 	 *
451 	 * The IP does not define a way to achieve 1/1.  For UniPhier variants,
452 	 * bit10 is used for 1/1.  Newer versions of UniPhier variants use
453 	 * bit16 for 1/1024.
454 	 */
455 	if (divisor <= 1)
456 		tmp |= UNIPHIER_SD_CLK_CTL_DIV1;
457 	else if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP && divisor > 512)
458 		tmp |= UNIPHIER_SD_CLK_CTL_DIV1024;
459 	else
460 		tmp |= roundup_pow_of_two(divisor) >> 2;
461 
462 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
463 
464 	tmp |= CLK_CTL_SCLKEN;
465 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
466 }
467 
468 static void uniphier_sd_host_init(struct tmio_mmc_host *host)
469 {
470 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
471 	u32 val;
472 
473 	/*
474 	 * Connected to 32bit AXI.
475 	 * This register holds settings for SoC-specific internal bus
476 	 * connection.  What is worse, the register spec was changed,
477 	 * breaking the backward compatibility.  Write an appropriate
478 	 * value depending on a flag associated with a compatible string.
479 	 */
480 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
481 		val = 0x00000101;
482 	else
483 		val = 0x00000000;
484 
485 	writel(val, host->ctl + UNIPHIER_SD_HOST_MODE);
486 
487 	val = 0;
488 	/*
489 	 * If supported, the controller can automatically
490 	 * enable/disable the clock line to the card.
491 	 */
492 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
493 		val |= UNIPHIER_SD_CLKCTL_OFFEN;
494 
495 	writel(val, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
496 }
497 
498 static int uniphier_sd_start_signal_voltage_switch(struct mmc_host *mmc,
499 						   struct mmc_ios *ios)
500 {
501 	struct tmio_mmc_host *host = mmc_priv(mmc);
502 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
503 	struct pinctrl_state *pinstate = NULL;
504 	u32 val, tmp;
505 
506 	switch (ios->signal_voltage) {
507 	case MMC_SIGNAL_VOLTAGE_330:
508 		val = UNIPHIER_SD_VOLT_330;
509 		break;
510 	case MMC_SIGNAL_VOLTAGE_180:
511 		val = UNIPHIER_SD_VOLT_180;
512 		pinstate = priv->pinstate_uhs;
513 		break;
514 	default:
515 		return -ENOTSUPP;
516 	}
517 
518 	tmp = readl(host->ctl + UNIPHIER_SD_VOLT);
519 	tmp &= ~UNIPHIER_SD_VOLT_MASK;
520 	tmp |= FIELD_PREP(UNIPHIER_SD_VOLT_MASK, val);
521 	writel(tmp, host->ctl + UNIPHIER_SD_VOLT);
522 
523 	if (pinstate)
524 		pinctrl_select_state(priv->pinctrl, pinstate);
525 	else
526 		pinctrl_select_default_state(mmc_dev(mmc));
527 
528 	return 0;
529 }
530 
531 static int uniphier_sd_uhs_init(struct tmio_mmc_host *host,
532 				struct uniphier_sd_priv *priv)
533 {
534 	priv->pinctrl = devm_pinctrl_get(mmc_dev(host->mmc));
535 	if (IS_ERR(priv->pinctrl))
536 		return PTR_ERR(priv->pinctrl);
537 
538 	priv->pinstate_uhs = pinctrl_lookup_state(priv->pinctrl, "uhs");
539 	if (IS_ERR(priv->pinstate_uhs))
540 		return PTR_ERR(priv->pinstate_uhs);
541 
542 	host->ops.start_signal_voltage_switch =
543 					uniphier_sd_start_signal_voltage_switch;
544 
545 	return 0;
546 }
547 
548 static int uniphier_sd_probe(struct platform_device *pdev)
549 {
550 	struct device *dev = &pdev->dev;
551 	struct uniphier_sd_priv *priv;
552 	struct tmio_mmc_data *tmio_data;
553 	struct tmio_mmc_host *host;
554 	int irq, ret;
555 
556 	irq = platform_get_irq(pdev, 0);
557 	if (irq < 0)
558 		return irq;
559 
560 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
561 	if (!priv)
562 		return -ENOMEM;
563 
564 	priv->caps = (unsigned long)of_device_get_match_data(dev);
565 
566 	priv->clk = devm_clk_get(dev, NULL);
567 	if (IS_ERR(priv->clk)) {
568 		dev_err(dev, "failed to get clock\n");
569 		return PTR_ERR(priv->clk);
570 	}
571 
572 	priv->rst = devm_reset_control_get_shared(dev, "host");
573 	if (IS_ERR(priv->rst)) {
574 		dev_err(dev, "failed to get host reset\n");
575 		return PTR_ERR(priv->rst);
576 	}
577 
578 	/* old version has one more reset */
579 	if (!(priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)) {
580 		priv->rst_br = devm_reset_control_get_shared(dev, "bridge");
581 		if (IS_ERR(priv->rst_br)) {
582 			dev_err(dev, "failed to get bridge reset\n");
583 			return PTR_ERR(priv->rst_br);
584 		}
585 	}
586 
587 	tmio_data = &priv->tmio_data;
588 	tmio_data->flags |= TMIO_MMC_32BIT_DATA_PORT;
589 	tmio_data->flags |= TMIO_MMC_USE_BUSY_TIMEOUT;
590 
591 	host = tmio_mmc_host_alloc(pdev, tmio_data);
592 	if (IS_ERR(host))
593 		return PTR_ERR(host);
594 
595 	if (host->mmc->caps & MMC_CAP_HW_RESET) {
596 		priv->rst_hw = devm_reset_control_get_exclusive(dev, "hw");
597 		if (IS_ERR(priv->rst_hw)) {
598 			dev_err(dev, "failed to get hw reset\n");
599 			ret = PTR_ERR(priv->rst_hw);
600 			goto free_host;
601 		}
602 		host->ops.hw_reset = uniphier_sd_hw_reset;
603 	}
604 
605 	if (host->mmc->caps & MMC_CAP_UHS) {
606 		ret = uniphier_sd_uhs_init(host, priv);
607 		if (ret) {
608 			dev_warn(dev,
609 				 "failed to setup UHS (error %d).  Disabling UHS.",
610 				 ret);
611 			host->mmc->caps &= ~MMC_CAP_UHS;
612 		}
613 	}
614 
615 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
616 		host->dma_ops = &uniphier_sd_internal_dma_ops;
617 	else
618 		host->dma_ops = &uniphier_sd_external_dma_ops;
619 
620 	host->bus_shift = 1;
621 	host->clk_enable = uniphier_sd_clk_enable;
622 	host->clk_disable = uniphier_sd_clk_disable;
623 	host->set_clock = uniphier_sd_set_clock;
624 
625 	ret = uniphier_sd_clk_enable(host);
626 	if (ret)
627 		goto free_host;
628 
629 	uniphier_sd_host_init(host);
630 
631 	tmio_data->ocr_mask = MMC_VDD_32_33 | MMC_VDD_33_34;
632 	if (host->mmc->caps & MMC_CAP_UHS)
633 		tmio_data->ocr_mask |= MMC_VDD_165_195;
634 
635 	tmio_data->max_segs = 1;
636 	tmio_data->max_blk_count = U16_MAX;
637 
638 	ret = tmio_mmc_host_probe(host);
639 	if (ret)
640 		goto free_host;
641 
642 	ret = devm_request_irq(dev, irq, tmio_mmc_irq, IRQF_SHARED,
643 			       dev_name(dev), host);
644 	if (ret)
645 		goto remove_host;
646 
647 	return 0;
648 
649 remove_host:
650 	tmio_mmc_host_remove(host);
651 free_host:
652 	tmio_mmc_host_free(host);
653 
654 	return ret;
655 }
656 
657 static int uniphier_sd_remove(struct platform_device *pdev)
658 {
659 	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
660 
661 	tmio_mmc_host_remove(host);
662 	uniphier_sd_clk_disable(host);
663 
664 	return 0;
665 }
666 
667 static const struct of_device_id uniphier_sd_match[] = {
668 	{
669 		.compatible = "socionext,uniphier-sd-v2.91",
670 	},
671 	{
672 		.compatible = "socionext,uniphier-sd-v3.1",
673 		.data = (void *)(UNIPHIER_SD_CAP_EXTENDED_IP |
674 				 UNIPHIER_SD_CAP_BROKEN_DMA_RX),
675 	},
676 	{
677 		.compatible = "socionext,uniphier-sd-v3.1.1",
678 		.data = (void *)UNIPHIER_SD_CAP_EXTENDED_IP,
679 	},
680 	{ /* sentinel */ }
681 };
682 MODULE_DEVICE_TABLE(of, uniphier_sd_match);
683 
684 static struct platform_driver uniphier_sd_driver = {
685 	.probe = uniphier_sd_probe,
686 	.remove = uniphier_sd_remove,
687 	.driver = {
688 		.name = "uniphier-sd",
689 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
690 		.of_match_table = uniphier_sd_match,
691 	},
692 };
693 module_platform_driver(uniphier_sd_driver);
694 
695 MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
696 MODULE_DESCRIPTION("UniPhier SD/eMMC host controller driver");
697 MODULE_LICENSE("GPL v2");
698