xref: /openbmc/linux/drivers/mmc/host/uniphier-sd.c (revision babbdf5b)
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(struct tasklet_struct *t)
85 {
86 	struct tmio_mmc_host *host = from_tasklet(host, t, dma_issue);
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_setup(&host->dma_issue, uniphier_sd_external_dma_issue);
194 }
195 
196 static void uniphier_sd_external_dma_release(struct tmio_mmc_host *host)
197 {
198 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
199 
200 	if (priv->chan)
201 		dma_release_channel(priv->chan);
202 }
203 
204 static void uniphier_sd_external_dma_abort(struct tmio_mmc_host *host)
205 {
206 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
207 
208 	uniphier_sd_dma_endisable(host, 0);
209 
210 	if (priv->chan)
211 		dmaengine_terminate_sync(priv->chan);
212 }
213 
214 static void uniphier_sd_external_dma_dataend(struct tmio_mmc_host *host)
215 {
216 	uniphier_sd_dma_endisable(host, 0);
217 
218 	tmio_mmc_do_data_irq(host);
219 }
220 
221 static const struct tmio_mmc_dma_ops uniphier_sd_external_dma_ops = {
222 	.start = uniphier_sd_external_dma_start,
223 	.enable = uniphier_sd_external_dma_enable,
224 	.request = uniphier_sd_external_dma_request,
225 	.release = uniphier_sd_external_dma_release,
226 	.abort = uniphier_sd_external_dma_abort,
227 	.dataend = uniphier_sd_external_dma_dataend,
228 };
229 
230 static void uniphier_sd_internal_dma_issue(struct tasklet_struct *t)
231 {
232 	struct tmio_mmc_host *host = from_tasklet(host, t, dma_issue);
233 	unsigned long flags;
234 
235 	spin_lock_irqsave(&host->lock, flags);
236 	tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
237 	spin_unlock_irqrestore(&host->lock, flags);
238 
239 	uniphier_sd_dma_endisable(host, 1);
240 	writel(UNIPHIER_SD_DMA_CTL_START, host->ctl + UNIPHIER_SD_DMA_CTL);
241 }
242 
243 static void uniphier_sd_internal_dma_start(struct tmio_mmc_host *host,
244 					   struct mmc_data *data)
245 {
246 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
247 	struct scatterlist *sg = host->sg_ptr;
248 	dma_addr_t dma_addr;
249 	unsigned int dma_mode_dir;
250 	u32 dma_mode;
251 	int sg_len;
252 
253 	if ((data->flags & MMC_DATA_READ) && !host->chan_rx)
254 		goto force_pio;
255 
256 	if (WARN_ON(host->sg_len != 1))
257 		goto force_pio;
258 
259 	if (!IS_ALIGNED(sg->offset, 8))
260 		goto force_pio;
261 
262 	if (data->flags & MMC_DATA_READ) {
263 		priv->dma_dir = DMA_FROM_DEVICE;
264 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV;
265 	} else {
266 		priv->dma_dir = DMA_TO_DEVICE;
267 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_TO_DEV;
268 	}
269 
270 	sg_len = dma_map_sg(mmc_dev(host->mmc), sg, 1, priv->dma_dir);
271 	if (sg_len == 0)
272 		goto force_pio;
273 
274 	dma_mode = FIELD_PREP(UNIPHIER_SD_DMA_MODE_DIR_MASK, dma_mode_dir);
275 	dma_mode |= FIELD_PREP(UNIPHIER_SD_DMA_MODE_WIDTH_MASK,
276 			       UNIPHIER_SD_DMA_MODE_WIDTH_64);
277 	dma_mode |= UNIPHIER_SD_DMA_MODE_ADDR_INC;
278 
279 	writel(dma_mode, host->ctl + UNIPHIER_SD_DMA_MODE);
280 
281 	dma_addr = sg_dma_address(data->sg);
282 	writel(lower_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_L);
283 	writel(upper_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_H);
284 
285 	host->dma_on = true;
286 
287 	return;
288 force_pio:
289 	uniphier_sd_dma_endisable(host, 0);
290 }
291 
292 static void uniphier_sd_internal_dma_enable(struct tmio_mmc_host *host,
293 					    bool enable)
294 {
295 }
296 
297 static void uniphier_sd_internal_dma_request(struct tmio_mmc_host *host,
298 					     struct tmio_mmc_data *pdata)
299 {
300 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
301 
302 	/*
303 	 * Due to a hardware bug, Pro5 cannot use DMA for RX.
304 	 * We can still use DMA for TX, but PIO for RX.
305 	 */
306 	if (!(priv->caps & UNIPHIER_SD_CAP_BROKEN_DMA_RX))
307 		host->chan_rx = (void *)0xdeadbeaf;
308 
309 	host->chan_tx = (void *)0xdeadbeaf;
310 
311 	tasklet_setup(&host->dma_issue, uniphier_sd_internal_dma_issue);
312 }
313 
314 static void uniphier_sd_internal_dma_release(struct tmio_mmc_host *host)
315 {
316 	/* Each value is set to zero to assume "disabling" each DMA */
317 	host->chan_rx = NULL;
318 	host->chan_tx = NULL;
319 }
320 
321 static void uniphier_sd_internal_dma_abort(struct tmio_mmc_host *host)
322 {
323 	u32 tmp;
324 
325 	uniphier_sd_dma_endisable(host, 0);
326 
327 	tmp = readl(host->ctl + UNIPHIER_SD_DMA_RST);
328 	tmp &= ~(UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0);
329 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
330 
331 	tmp |= UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0;
332 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
333 }
334 
335 static void uniphier_sd_internal_dma_dataend(struct tmio_mmc_host *host)
336 {
337 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
338 
339 	uniphier_sd_dma_endisable(host, 0);
340 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, 1, priv->dma_dir);
341 
342 	tmio_mmc_do_data_irq(host);
343 }
344 
345 static const struct tmio_mmc_dma_ops uniphier_sd_internal_dma_ops = {
346 	.start = uniphier_sd_internal_dma_start,
347 	.enable = uniphier_sd_internal_dma_enable,
348 	.request = uniphier_sd_internal_dma_request,
349 	.release = uniphier_sd_internal_dma_release,
350 	.abort = uniphier_sd_internal_dma_abort,
351 	.dataend = uniphier_sd_internal_dma_dataend,
352 };
353 
354 static int uniphier_sd_clk_enable(struct tmio_mmc_host *host)
355 {
356 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
357 	struct mmc_host *mmc = host->mmc;
358 	int ret;
359 
360 	ret = clk_prepare_enable(priv->clk);
361 	if (ret)
362 		return ret;
363 
364 	ret = clk_set_rate(priv->clk, ULONG_MAX);
365 	if (ret)
366 		goto disable_clk;
367 
368 	priv->clk_rate = clk_get_rate(priv->clk);
369 
370 	/* If max-frequency property is set, use it. */
371 	if (!mmc->f_max)
372 		mmc->f_max = priv->clk_rate;
373 
374 	/*
375 	 * 1/512 is the finest divisor in the original IP.  Newer versions
376 	 * also supports 1/1024 divisor. (UniPhier-specific extension)
377 	 */
378 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
379 		mmc->f_min = priv->clk_rate / 1024;
380 	else
381 		mmc->f_min = priv->clk_rate / 512;
382 
383 	ret = reset_control_deassert(priv->rst);
384 	if (ret)
385 		goto disable_clk;
386 
387 	ret = reset_control_deassert(priv->rst_br);
388 	if (ret)
389 		goto assert_rst;
390 
391 	return 0;
392 
393 assert_rst:
394 	reset_control_assert(priv->rst);
395 disable_clk:
396 	clk_disable_unprepare(priv->clk);
397 
398 	return ret;
399 }
400 
401 static void uniphier_sd_clk_disable(struct tmio_mmc_host *host)
402 {
403 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
404 
405 	reset_control_assert(priv->rst_br);
406 	reset_control_assert(priv->rst);
407 	clk_disable_unprepare(priv->clk);
408 }
409 
410 static void uniphier_sd_hw_reset(struct mmc_host *mmc)
411 {
412 	struct tmio_mmc_host *host = mmc_priv(mmc);
413 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
414 
415 	reset_control_assert(priv->rst_hw);
416 	/* For eMMC, minimum is 1us but give it 9us for good measure */
417 	udelay(9);
418 	reset_control_deassert(priv->rst_hw);
419 	/* For eMMC, minimum is 200us but give it 300us for good measure */
420 	usleep_range(300, 1000);
421 }
422 
423 static void uniphier_sd_set_clock(struct tmio_mmc_host *host,
424 				  unsigned int clock)
425 {
426 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
427 	unsigned long divisor;
428 	u32 tmp;
429 
430 	tmp = readl(host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
431 
432 	/* stop the clock before changing its rate to avoid a glitch signal */
433 	tmp &= ~CLK_CTL_SCLKEN;
434 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
435 
436 	if (clock == 0)
437 		return;
438 
439 	tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1024;
440 	tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1;
441 	tmp &= ~CLK_CTL_DIV_MASK;
442 
443 	divisor = priv->clk_rate / clock;
444 
445 	/*
446 	 * In the original IP, bit[7:0] represents the divisor.
447 	 * bit7 set: 1/512, ... bit0 set:1/4, all bits clear: 1/2
448 	 *
449 	 * The IP does not define a way to achieve 1/1.  For UniPhier variants,
450 	 * bit10 is used for 1/1.  Newer versions of UniPhier variants use
451 	 * bit16 for 1/1024.
452 	 */
453 	if (divisor <= 1)
454 		tmp |= UNIPHIER_SD_CLK_CTL_DIV1;
455 	else if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP && divisor > 512)
456 		tmp |= UNIPHIER_SD_CLK_CTL_DIV1024;
457 	else
458 		tmp |= roundup_pow_of_two(divisor) >> 2;
459 
460 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
461 
462 	tmp |= CLK_CTL_SCLKEN;
463 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
464 }
465 
466 static void uniphier_sd_host_init(struct tmio_mmc_host *host)
467 {
468 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
469 	u32 val;
470 
471 	/*
472 	 * Connected to 32bit AXI.
473 	 * This register holds settings for SoC-specific internal bus
474 	 * connection.  What is worse, the register spec was changed,
475 	 * breaking the backward compatibility.  Write an appropriate
476 	 * value depending on a flag associated with a compatible string.
477 	 */
478 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
479 		val = 0x00000101;
480 	else
481 		val = 0x00000000;
482 
483 	writel(val, host->ctl + UNIPHIER_SD_HOST_MODE);
484 
485 	val = 0;
486 	/*
487 	 * If supported, the controller can automatically
488 	 * enable/disable the clock line to the card.
489 	 */
490 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
491 		val |= UNIPHIER_SD_CLKCTL_OFFEN;
492 
493 	writel(val, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
494 }
495 
496 static int uniphier_sd_start_signal_voltage_switch(struct mmc_host *mmc,
497 						   struct mmc_ios *ios)
498 {
499 	struct tmio_mmc_host *host = mmc_priv(mmc);
500 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
501 	struct pinctrl_state *pinstate = NULL;
502 	u32 val, tmp;
503 
504 	switch (ios->signal_voltage) {
505 	case MMC_SIGNAL_VOLTAGE_330:
506 		val = UNIPHIER_SD_VOLT_330;
507 		break;
508 	case MMC_SIGNAL_VOLTAGE_180:
509 		val = UNIPHIER_SD_VOLT_180;
510 		pinstate = priv->pinstate_uhs;
511 		break;
512 	default:
513 		return -ENOTSUPP;
514 	}
515 
516 	tmp = readl(host->ctl + UNIPHIER_SD_VOLT);
517 	tmp &= ~UNIPHIER_SD_VOLT_MASK;
518 	tmp |= FIELD_PREP(UNIPHIER_SD_VOLT_MASK, val);
519 	writel(tmp, host->ctl + UNIPHIER_SD_VOLT);
520 
521 	if (pinstate)
522 		pinctrl_select_state(priv->pinctrl, pinstate);
523 	else
524 		pinctrl_select_default_state(mmc_dev(mmc));
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_uhs = pinctrl_lookup_state(priv->pinctrl, "uhs");
537 	if (IS_ERR(priv->pinstate_uhs))
538 		return PTR_ERR(priv->pinstate_uhs);
539 
540 	host->ops.start_signal_voltage_switch =
541 					uniphier_sd_start_signal_voltage_switch;
542 
543 	return 0;
544 }
545 
546 static int uniphier_sd_probe(struct platform_device *pdev)
547 {
548 	struct device *dev = &pdev->dev;
549 	struct uniphier_sd_priv *priv;
550 	struct tmio_mmc_data *tmio_data;
551 	struct tmio_mmc_host *host;
552 	int irq, ret;
553 
554 	irq = platform_get_irq(pdev, 0);
555 	if (irq < 0)
556 		return irq;
557 
558 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
559 	if (!priv)
560 		return -ENOMEM;
561 
562 	priv->caps = (unsigned long)of_device_get_match_data(dev);
563 
564 	priv->clk = devm_clk_get(dev, NULL);
565 	if (IS_ERR(priv->clk)) {
566 		dev_err(dev, "failed to get clock\n");
567 		return PTR_ERR(priv->clk);
568 	}
569 
570 	priv->rst = devm_reset_control_get_shared(dev, "host");
571 	if (IS_ERR(priv->rst)) {
572 		dev_err(dev, "failed to get host reset\n");
573 		return PTR_ERR(priv->rst);
574 	}
575 
576 	/* old version has one more reset */
577 	if (!(priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)) {
578 		priv->rst_br = devm_reset_control_get_shared(dev, "bridge");
579 		if (IS_ERR(priv->rst_br)) {
580 			dev_err(dev, "failed to get bridge reset\n");
581 			return PTR_ERR(priv->rst_br);
582 		}
583 	}
584 
585 	tmio_data = &priv->tmio_data;
586 	tmio_data->flags |= TMIO_MMC_32BIT_DATA_PORT;
587 	tmio_data->flags |= TMIO_MMC_USE_BUSY_TIMEOUT;
588 
589 	host = tmio_mmc_host_alloc(pdev, tmio_data);
590 	if (IS_ERR(host))
591 		return PTR_ERR(host);
592 
593 	if (host->mmc->caps & MMC_CAP_HW_RESET) {
594 		priv->rst_hw = devm_reset_control_get_exclusive(dev, "hw");
595 		if (IS_ERR(priv->rst_hw)) {
596 			dev_err(dev, "failed to get hw reset\n");
597 			ret = PTR_ERR(priv->rst_hw);
598 			goto free_host;
599 		}
600 		host->ops.hw_reset = uniphier_sd_hw_reset;
601 	}
602 
603 	if (host->mmc->caps & MMC_CAP_UHS) {
604 		ret = uniphier_sd_uhs_init(host, priv);
605 		if (ret) {
606 			dev_warn(dev,
607 				 "failed to setup UHS (error %d).  Disabling UHS.",
608 				 ret);
609 			host->mmc->caps &= ~MMC_CAP_UHS;
610 		}
611 	}
612 
613 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
614 		host->dma_ops = &uniphier_sd_internal_dma_ops;
615 	else
616 		host->dma_ops = &uniphier_sd_external_dma_ops;
617 
618 	host->bus_shift = 1;
619 	host->clk_enable = uniphier_sd_clk_enable;
620 	host->clk_disable = uniphier_sd_clk_disable;
621 	host->set_clock = uniphier_sd_set_clock;
622 
623 	ret = uniphier_sd_clk_enable(host);
624 	if (ret)
625 		goto free_host;
626 
627 	uniphier_sd_host_init(host);
628 
629 	tmio_data->ocr_mask = MMC_VDD_32_33 | MMC_VDD_33_34;
630 	if (host->mmc->caps & MMC_CAP_UHS)
631 		tmio_data->ocr_mask |= MMC_VDD_165_195;
632 
633 	tmio_data->max_segs = 1;
634 	tmio_data->max_blk_count = U16_MAX;
635 
636 	ret = tmio_mmc_host_probe(host);
637 	if (ret)
638 		goto disable_clk;
639 
640 	ret = devm_request_irq(dev, irq, tmio_mmc_irq, IRQF_SHARED,
641 			       dev_name(dev), host);
642 	if (ret)
643 		goto remove_host;
644 
645 	return 0;
646 
647 remove_host:
648 	tmio_mmc_host_remove(host);
649 disable_clk:
650 	uniphier_sd_clk_disable(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 	tmio_mmc_host_free(host);
664 
665 	return 0;
666 }
667 
668 static const struct of_device_id uniphier_sd_match[] = {
669 	{
670 		.compatible = "socionext,uniphier-sd-v2.91",
671 	},
672 	{
673 		.compatible = "socionext,uniphier-sd-v3.1",
674 		.data = (void *)(UNIPHIER_SD_CAP_EXTENDED_IP |
675 				 UNIPHIER_SD_CAP_BROKEN_DMA_RX),
676 	},
677 	{
678 		.compatible = "socionext,uniphier-sd-v3.1.1",
679 		.data = (void *)UNIPHIER_SD_CAP_EXTENDED_IP,
680 	},
681 	{ /* sentinel */ }
682 };
683 MODULE_DEVICE_TABLE(of, uniphier_sd_match);
684 
685 static struct platform_driver uniphier_sd_driver = {
686 	.probe = uniphier_sd_probe,
687 	.remove = uniphier_sd_remove,
688 	.driver = {
689 		.name = "uniphier-sd",
690 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
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