xref: /openbmc/linux/drivers/mmc/host/uniphier-sd.c (revision be709d48)
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_default;
63 	struct pinctrl_state *pinstate_uhs;
64 	struct clk *clk;
65 	struct reset_control *rst;
66 	struct reset_control *rst_br;
67 	struct reset_control *rst_hw;
68 	struct dma_chan *chan;
69 	enum dma_data_direction dma_dir;
70 	unsigned long clk_rate;
71 	unsigned long caps;
72 };
73 
74 static void *uniphier_sd_priv(struct tmio_mmc_host *host)
75 {
76 	return container_of(host->pdata, struct uniphier_sd_priv, tmio_data);
77 }
78 
79 static void uniphier_sd_dma_endisable(struct tmio_mmc_host *host, int enable)
80 {
81 	sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
82 }
83 
84 /* external DMA engine */
85 static void uniphier_sd_external_dma_issue(unsigned long arg)
86 {
87 	struct tmio_mmc_host *host = (void *)arg;
88 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
89 
90 	uniphier_sd_dma_endisable(host, 1);
91 	dma_async_issue_pending(priv->chan);
92 }
93 
94 static void uniphier_sd_external_dma_callback(void *param,
95 					const struct dmaengine_result *result)
96 {
97 	struct tmio_mmc_host *host = param;
98 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
99 	unsigned long flags;
100 
101 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
102 		     priv->dma_dir);
103 
104 	spin_lock_irqsave(&host->lock, flags);
105 
106 	if (result->result == DMA_TRANS_NOERROR) {
107 		/*
108 		 * When the external DMA engine is enabled, strangely enough,
109 		 * the DATAEND flag can be asserted even if the DMA engine has
110 		 * not been kicked yet.  Enable the TMIO_STAT_DATAEND irq only
111 		 * after we make sure the DMA engine finishes the transfer,
112 		 * hence, in this callback.
113 		 */
114 		tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
115 	} else {
116 		host->data->error = -ETIMEDOUT;
117 		tmio_mmc_do_data_irq(host);
118 	}
119 
120 	spin_unlock_irqrestore(&host->lock, flags);
121 }
122 
123 static void uniphier_sd_external_dma_start(struct tmio_mmc_host *host,
124 					   struct mmc_data *data)
125 {
126 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
127 	enum dma_transfer_direction dma_tx_dir;
128 	struct dma_async_tx_descriptor *desc;
129 	dma_cookie_t cookie;
130 	int sg_len;
131 
132 	if (!priv->chan)
133 		goto force_pio;
134 
135 	if (data->flags & MMC_DATA_READ) {
136 		priv->dma_dir = DMA_FROM_DEVICE;
137 		dma_tx_dir = DMA_DEV_TO_MEM;
138 	} else {
139 		priv->dma_dir = DMA_TO_DEVICE;
140 		dma_tx_dir = DMA_MEM_TO_DEV;
141 	}
142 
143 	sg_len = dma_map_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
144 			    priv->dma_dir);
145 	if (sg_len == 0)
146 		goto force_pio;
147 
148 	desc = dmaengine_prep_slave_sg(priv->chan, host->sg_ptr, sg_len,
149 				       dma_tx_dir, DMA_CTRL_ACK);
150 	if (!desc)
151 		goto unmap_sg;
152 
153 	desc->callback_result = uniphier_sd_external_dma_callback;
154 	desc->callback_param = host;
155 
156 	cookie = dmaengine_submit(desc);
157 	if (cookie < 0)
158 		goto unmap_sg;
159 
160 	host->dma_on = true;
161 
162 	return;
163 
164 unmap_sg:
165 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
166 		     priv->dma_dir);
167 force_pio:
168 	uniphier_sd_dma_endisable(host, 0);
169 }
170 
171 static void uniphier_sd_external_dma_enable(struct tmio_mmc_host *host,
172 					    bool enable)
173 {
174 }
175 
176 static void uniphier_sd_external_dma_request(struct tmio_mmc_host *host,
177 					     struct tmio_mmc_data *pdata)
178 {
179 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
180 	struct dma_chan *chan;
181 
182 	chan = dma_request_chan(mmc_dev(host->mmc), "rx-tx");
183 	if (IS_ERR(chan)) {
184 		dev_warn(mmc_dev(host->mmc),
185 			 "failed to request DMA channel. falling back to PIO\n");
186 		return;	/* just use PIO even for -EPROBE_DEFER */
187 	}
188 
189 	/* this driver uses a single channel for both RX an TX */
190 	priv->chan = chan;
191 	host->chan_rx = chan;
192 	host->chan_tx = chan;
193 
194 	tasklet_init(&host->dma_issue, uniphier_sd_external_dma_issue,
195 		     (unsigned long)host);
196 }
197 
198 static void uniphier_sd_external_dma_release(struct tmio_mmc_host *host)
199 {
200 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
201 
202 	if (priv->chan)
203 		dma_release_channel(priv->chan);
204 }
205 
206 static void uniphier_sd_external_dma_abort(struct tmio_mmc_host *host)
207 {
208 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
209 
210 	uniphier_sd_dma_endisable(host, 0);
211 
212 	if (priv->chan)
213 		dmaengine_terminate_sync(priv->chan);
214 }
215 
216 static void uniphier_sd_external_dma_dataend(struct tmio_mmc_host *host)
217 {
218 	uniphier_sd_dma_endisable(host, 0);
219 
220 	tmio_mmc_do_data_irq(host);
221 }
222 
223 static const struct tmio_mmc_dma_ops uniphier_sd_external_dma_ops = {
224 	.start = uniphier_sd_external_dma_start,
225 	.enable = uniphier_sd_external_dma_enable,
226 	.request = uniphier_sd_external_dma_request,
227 	.release = uniphier_sd_external_dma_release,
228 	.abort = uniphier_sd_external_dma_abort,
229 	.dataend = uniphier_sd_external_dma_dataend,
230 };
231 
232 static void uniphier_sd_internal_dma_issue(unsigned long arg)
233 {
234 	struct tmio_mmc_host *host = (void *)arg;
235 	unsigned long flags;
236 
237 	spin_lock_irqsave(&host->lock, flags);
238 	tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
239 	spin_unlock_irqrestore(&host->lock, flags);
240 
241 	uniphier_sd_dma_endisable(host, 1);
242 	writel(UNIPHIER_SD_DMA_CTL_START, host->ctl + UNIPHIER_SD_DMA_CTL);
243 }
244 
245 static void uniphier_sd_internal_dma_start(struct tmio_mmc_host *host,
246 					   struct mmc_data *data)
247 {
248 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
249 	struct scatterlist *sg = host->sg_ptr;
250 	dma_addr_t dma_addr;
251 	unsigned int dma_mode_dir;
252 	u32 dma_mode;
253 	int sg_len;
254 
255 	if ((data->flags & MMC_DATA_READ) && !host->chan_rx)
256 		goto force_pio;
257 
258 	if (WARN_ON(host->sg_len != 1))
259 		goto force_pio;
260 
261 	if (!IS_ALIGNED(sg->offset, 8))
262 		goto force_pio;
263 
264 	if (data->flags & MMC_DATA_READ) {
265 		priv->dma_dir = DMA_FROM_DEVICE;
266 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV;
267 	} else {
268 		priv->dma_dir = DMA_TO_DEVICE;
269 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_TO_DEV;
270 	}
271 
272 	sg_len = dma_map_sg(mmc_dev(host->mmc), sg, 1, priv->dma_dir);
273 	if (sg_len == 0)
274 		goto force_pio;
275 
276 	dma_mode = FIELD_PREP(UNIPHIER_SD_DMA_MODE_DIR_MASK, dma_mode_dir);
277 	dma_mode |= FIELD_PREP(UNIPHIER_SD_DMA_MODE_WIDTH_MASK,
278 			       UNIPHIER_SD_DMA_MODE_WIDTH_64);
279 	dma_mode |= UNIPHIER_SD_DMA_MODE_ADDR_INC;
280 
281 	writel(dma_mode, host->ctl + UNIPHIER_SD_DMA_MODE);
282 
283 	dma_addr = sg_dma_address(data->sg);
284 	writel(lower_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_L);
285 	writel(upper_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_H);
286 
287 	host->dma_on = true;
288 
289 	return;
290 force_pio:
291 	uniphier_sd_dma_endisable(host, 0);
292 }
293 
294 static void uniphier_sd_internal_dma_enable(struct tmio_mmc_host *host,
295 					    bool enable)
296 {
297 }
298 
299 static void uniphier_sd_internal_dma_request(struct tmio_mmc_host *host,
300 					     struct tmio_mmc_data *pdata)
301 {
302 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
303 
304 	/*
305 	 * Due to a hardware bug, Pro5 cannot use DMA for RX.
306 	 * We can still use DMA for TX, but PIO for RX.
307 	 */
308 	if (!(priv->caps & UNIPHIER_SD_CAP_BROKEN_DMA_RX))
309 		host->chan_rx = (void *)0xdeadbeaf;
310 
311 	host->chan_tx = (void *)0xdeadbeaf;
312 
313 	tasklet_init(&host->dma_issue, uniphier_sd_internal_dma_issue,
314 		     (unsigned long)host);
315 }
316 
317 static void uniphier_sd_internal_dma_release(struct tmio_mmc_host *host)
318 {
319 	/* Each value is set to zero to assume "disabling" each DMA */
320 	host->chan_rx = NULL;
321 	host->chan_tx = NULL;
322 }
323 
324 static void uniphier_sd_internal_dma_abort(struct tmio_mmc_host *host)
325 {
326 	u32 tmp;
327 
328 	uniphier_sd_dma_endisable(host, 0);
329 
330 	tmp = readl(host->ctl + UNIPHIER_SD_DMA_RST);
331 	tmp &= ~(UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0);
332 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
333 
334 	tmp |= UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0;
335 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
336 }
337 
338 static void uniphier_sd_internal_dma_dataend(struct tmio_mmc_host *host)
339 {
340 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
341 
342 	uniphier_sd_dma_endisable(host, 0);
343 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, 1, priv->dma_dir);
344 
345 	tmio_mmc_do_data_irq(host);
346 }
347 
348 static const struct tmio_mmc_dma_ops uniphier_sd_internal_dma_ops = {
349 	.start = uniphier_sd_internal_dma_start,
350 	.enable = uniphier_sd_internal_dma_enable,
351 	.request = uniphier_sd_internal_dma_request,
352 	.release = uniphier_sd_internal_dma_release,
353 	.abort = uniphier_sd_internal_dma_abort,
354 	.dataend = uniphier_sd_internal_dma_dataend,
355 };
356 
357 static int uniphier_sd_clk_enable(struct tmio_mmc_host *host)
358 {
359 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
360 	struct mmc_host *mmc = host->mmc;
361 	int ret;
362 
363 	ret = clk_prepare_enable(priv->clk);
364 	if (ret)
365 		return ret;
366 
367 	ret = clk_set_rate(priv->clk, ULONG_MAX);
368 	if (ret)
369 		goto disable_clk;
370 
371 	priv->clk_rate = clk_get_rate(priv->clk);
372 
373 	/* If max-frequency property is set, use it. */
374 	if (!mmc->f_max)
375 		mmc->f_max = priv->clk_rate;
376 
377 	/*
378 	 * 1/512 is the finest divisor in the original IP.  Newer versions
379 	 * also supports 1/1024 divisor. (UniPhier-specific extension)
380 	 */
381 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
382 		mmc->f_min = priv->clk_rate / 1024;
383 	else
384 		mmc->f_min = priv->clk_rate / 512;
385 
386 	ret = reset_control_deassert(priv->rst);
387 	if (ret)
388 		goto disable_clk;
389 
390 	ret = reset_control_deassert(priv->rst_br);
391 	if (ret)
392 		goto assert_rst;
393 
394 	return 0;
395 
396 assert_rst:
397 	reset_control_assert(priv->rst);
398 disable_clk:
399 	clk_disable_unprepare(priv->clk);
400 
401 	return ret;
402 }
403 
404 static void uniphier_sd_clk_disable(struct tmio_mmc_host *host)
405 {
406 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
407 
408 	reset_control_assert(priv->rst_br);
409 	reset_control_assert(priv->rst);
410 	clk_disable_unprepare(priv->clk);
411 }
412 
413 static void uniphier_sd_hw_reset(struct tmio_mmc_host *host)
414 {
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;
504 	u32 val, tmp;
505 
506 	switch (ios->signal_voltage) {
507 	case MMC_SIGNAL_VOLTAGE_330:
508 		val = UNIPHIER_SD_VOLT_330;
509 		pinstate = priv->pinstate_default;
510 		break;
511 	case MMC_SIGNAL_VOLTAGE_180:
512 		val = UNIPHIER_SD_VOLT_180;
513 		pinstate = priv->pinstate_uhs;
514 		break;
515 	default:
516 		return -ENOTSUPP;
517 	}
518 
519 	tmp = readl(host->ctl + UNIPHIER_SD_VOLT);
520 	tmp &= ~UNIPHIER_SD_VOLT_MASK;
521 	tmp |= FIELD_PREP(UNIPHIER_SD_VOLT_MASK, val);
522 	writel(tmp, host->ctl + UNIPHIER_SD_VOLT);
523 
524 	pinctrl_select_state(priv->pinctrl, pinstate);
525 
526 	return 0;
527 }
528 
529 static int uniphier_sd_uhs_init(struct tmio_mmc_host *host,
530 				struct uniphier_sd_priv *priv)
531 {
532 	priv->pinctrl = devm_pinctrl_get(mmc_dev(host->mmc));
533 	if (IS_ERR(priv->pinctrl))
534 		return PTR_ERR(priv->pinctrl);
535 
536 	priv->pinstate_default = pinctrl_lookup_state(priv->pinctrl,
537 						      PINCTRL_STATE_DEFAULT);
538 	if (IS_ERR(priv->pinstate_default))
539 		return PTR_ERR(priv->pinstate_default);
540 
541 	priv->pinstate_uhs = pinctrl_lookup_state(priv->pinctrl, "uhs");
542 	if (IS_ERR(priv->pinstate_uhs))
543 		return PTR_ERR(priv->pinstate_uhs);
544 
545 	host->ops.start_signal_voltage_switch =
546 					uniphier_sd_start_signal_voltage_switch;
547 
548 	return 0;
549 }
550 
551 static int uniphier_sd_probe(struct platform_device *pdev)
552 {
553 	struct device *dev = &pdev->dev;
554 	struct uniphier_sd_priv *priv;
555 	struct tmio_mmc_data *tmio_data;
556 	struct tmio_mmc_host *host;
557 	int irq, ret;
558 
559 	irq = platform_get_irq(pdev, 0);
560 	if (irq < 0) {
561 		dev_err(dev, "failed to get IRQ number");
562 		return irq;
563 	}
564 
565 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
566 	if (!priv)
567 		return -ENOMEM;
568 
569 	priv->caps = (unsigned long)of_device_get_match_data(dev);
570 
571 	priv->clk = devm_clk_get(dev, NULL);
572 	if (IS_ERR(priv->clk)) {
573 		dev_err(dev, "failed to get clock\n");
574 		return PTR_ERR(priv->clk);
575 	}
576 
577 	priv->rst = devm_reset_control_get_shared(dev, "host");
578 	if (IS_ERR(priv->rst)) {
579 		dev_err(dev, "failed to get host reset\n");
580 		return PTR_ERR(priv->rst);
581 	}
582 
583 	/* old version has one more reset */
584 	if (!(priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)) {
585 		priv->rst_br = devm_reset_control_get_shared(dev, "bridge");
586 		if (IS_ERR(priv->rst_br)) {
587 			dev_err(dev, "failed to get bridge reset\n");
588 			return PTR_ERR(priv->rst_br);
589 		}
590 	}
591 
592 	tmio_data = &priv->tmio_data;
593 	tmio_data->flags |= TMIO_MMC_32BIT_DATA_PORT;
594 
595 	host = tmio_mmc_host_alloc(pdev, tmio_data);
596 	if (IS_ERR(host))
597 		return PTR_ERR(host);
598 
599 	if (host->mmc->caps & MMC_CAP_HW_RESET) {
600 		priv->rst_hw = devm_reset_control_get_exclusive(dev, "hw");
601 		if (IS_ERR(priv->rst_hw)) {
602 			dev_err(dev, "failed to get hw reset\n");
603 			ret = PTR_ERR(priv->rst_hw);
604 			goto free_host;
605 		}
606 		host->hw_reset = uniphier_sd_hw_reset;
607 	}
608 
609 	if (host->mmc->caps & MMC_CAP_UHS) {
610 		ret = uniphier_sd_uhs_init(host, priv);
611 		if (ret) {
612 			dev_warn(dev,
613 				 "failed to setup UHS (error %d).  Disabling UHS.",
614 				 ret);
615 			host->mmc->caps &= ~MMC_CAP_UHS;
616 		}
617 	}
618 
619 	ret = devm_request_irq(dev, irq, tmio_mmc_irq, IRQF_SHARED,
620 			       dev_name(dev), host);
621 	if (ret)
622 		goto free_host;
623 
624 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
625 		host->dma_ops = &uniphier_sd_internal_dma_ops;
626 	else
627 		host->dma_ops = &uniphier_sd_external_dma_ops;
628 
629 	host->bus_shift = 1;
630 	host->clk_enable = uniphier_sd_clk_enable;
631 	host->clk_disable = uniphier_sd_clk_disable;
632 	host->set_clock = uniphier_sd_set_clock;
633 
634 	ret = uniphier_sd_clk_enable(host);
635 	if (ret)
636 		goto free_host;
637 
638 	uniphier_sd_host_init(host);
639 
640 	tmio_data->ocr_mask = MMC_VDD_32_33 | MMC_VDD_33_34;
641 	if (host->mmc->caps & MMC_CAP_UHS)
642 		tmio_data->ocr_mask |= MMC_VDD_165_195;
643 
644 	tmio_data->max_segs = 1;
645 	tmio_data->max_blk_count = U16_MAX;
646 
647 	ret = tmio_mmc_host_probe(host);
648 	if (ret)
649 		goto free_host;
650 
651 	return 0;
652 
653 free_host:
654 	tmio_mmc_host_free(host);
655 
656 	return ret;
657 }
658 
659 static int uniphier_sd_remove(struct platform_device *pdev)
660 {
661 	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
662 
663 	tmio_mmc_host_remove(host);
664 	uniphier_sd_clk_disable(host);
665 
666 	return 0;
667 }
668 
669 static const struct of_device_id uniphier_sd_match[] = {
670 	{
671 		.compatible = "socionext,uniphier-sd-v2.91",
672 	},
673 	{
674 		.compatible = "socionext,uniphier-sd-v3.1",
675 		.data = (void *)(UNIPHIER_SD_CAP_EXTENDED_IP |
676 				 UNIPHIER_SD_CAP_BROKEN_DMA_RX),
677 	},
678 	{
679 		.compatible = "socionext,uniphier-sd-v3.1.1",
680 		.data = (void *)UNIPHIER_SD_CAP_EXTENDED_IP,
681 	},
682 	{ /* sentinel */ }
683 };
684 MODULE_DEVICE_TABLE(of, uniphier_sd_match);
685 
686 static struct platform_driver uniphier_sd_driver = {
687 	.probe = uniphier_sd_probe,
688 	.remove = uniphier_sd_remove,
689 	.driver = {
690 		.name = "uniphier-sd",
691 		.of_match_table = uniphier_sd_match,
692 	},
693 };
694 module_platform_driver(uniphier_sd_driver);
695 
696 MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
697 MODULE_DESCRIPTION("UniPhier SD/eMMC host controller driver");
698 MODULE_LICENSE("GPL v2");
699