xref: /linux/drivers/mmc/core/host.c (revision 132db93572821ec2fdf81e354cc40f558faf7e4f) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/core/host.c
4  *
5  *  Copyright (C) 2003 Russell King, All Rights Reserved.
6  *  Copyright (C) 2007-2008 Pierre Ossman
7  *  Copyright (C) 2010 Linus Walleij
8  *
9  *  MMC host class device management
10  */
11 
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/idr.h>
15 #include <linux/of.h>
16 #include <linux/of_gpio.h>
17 #include <linux/pagemap.h>
18 #include <linux/export.h>
19 #include <linux/leds.h>
20 #include <linux/slab.h>
21 
22 #include <linux/mmc/host.h>
23 #include <linux/mmc/card.h>
24 #include <linux/mmc/slot-gpio.h>
25 
26 #include "core.h"
27 #include "host.h"
28 #include "slot-gpio.h"
29 #include "pwrseq.h"
30 #include "sdio_ops.h"
31 
32 #define cls_dev_to_mmc_host(d)	container_of(d, struct mmc_host, class_dev)
33 
34 static DEFINE_IDA(mmc_host_ida);
35 
36 static void mmc_host_classdev_release(struct device *dev)
37 {
38 	struct mmc_host *host = cls_dev_to_mmc_host(dev);
39 	ida_simple_remove(&mmc_host_ida, host->index);
40 	kfree(host);
41 }
42 
43 static struct class mmc_host_class = {
44 	.name		= "mmc_host",
45 	.dev_release	= mmc_host_classdev_release,
46 };
47 
48 int mmc_register_host_class(void)
49 {
50 	return class_register(&mmc_host_class);
51 }
52 
53 void mmc_unregister_host_class(void)
54 {
55 	class_unregister(&mmc_host_class);
56 }
57 
58 void mmc_retune_enable(struct mmc_host *host)
59 {
60 	host->can_retune = 1;
61 	if (host->retune_period)
62 		mod_timer(&host->retune_timer,
63 			  jiffies + host->retune_period * HZ);
64 }
65 
66 /*
67  * Pause re-tuning for a small set of operations.  The pause begins after the
68  * next command and after first doing re-tuning.
69  */
70 void mmc_retune_pause(struct mmc_host *host)
71 {
72 	if (!host->retune_paused) {
73 		host->retune_paused = 1;
74 		mmc_retune_needed(host);
75 		mmc_retune_hold(host);
76 	}
77 }
78 EXPORT_SYMBOL(mmc_retune_pause);
79 
80 void mmc_retune_unpause(struct mmc_host *host)
81 {
82 	if (host->retune_paused) {
83 		host->retune_paused = 0;
84 		mmc_retune_release(host);
85 	}
86 }
87 EXPORT_SYMBOL(mmc_retune_unpause);
88 
89 void mmc_retune_disable(struct mmc_host *host)
90 {
91 	mmc_retune_unpause(host);
92 	host->can_retune = 0;
93 	del_timer_sync(&host->retune_timer);
94 	host->retune_now = 0;
95 	host->need_retune = 0;
96 }
97 
98 void mmc_retune_timer_stop(struct mmc_host *host)
99 {
100 	del_timer_sync(&host->retune_timer);
101 }
102 EXPORT_SYMBOL(mmc_retune_timer_stop);
103 
104 void mmc_retune_hold(struct mmc_host *host)
105 {
106 	if (!host->hold_retune)
107 		host->retune_now = 1;
108 	host->hold_retune += 1;
109 }
110 
111 void mmc_retune_release(struct mmc_host *host)
112 {
113 	if (host->hold_retune)
114 		host->hold_retune -= 1;
115 	else
116 		WARN_ON(1);
117 }
118 EXPORT_SYMBOL(mmc_retune_release);
119 
120 int mmc_retune(struct mmc_host *host)
121 {
122 	bool return_to_hs400 = false;
123 	int err;
124 
125 	if (host->retune_now)
126 		host->retune_now = 0;
127 	else
128 		return 0;
129 
130 	if (!host->need_retune || host->doing_retune || !host->card)
131 		return 0;
132 
133 	host->need_retune = 0;
134 
135 	host->doing_retune = 1;
136 
137 	if (host->ios.timing == MMC_TIMING_MMC_HS400) {
138 		err = mmc_hs400_to_hs200(host->card);
139 		if (err)
140 			goto out;
141 
142 		return_to_hs400 = true;
143 	}
144 
145 	err = mmc_execute_tuning(host->card);
146 	if (err)
147 		goto out;
148 
149 	if (return_to_hs400)
150 		err = mmc_hs200_to_hs400(host->card);
151 out:
152 	host->doing_retune = 0;
153 
154 	return err;
155 }
156 
157 static void mmc_retune_timer(struct timer_list *t)
158 {
159 	struct mmc_host *host = from_timer(host, t, retune_timer);
160 
161 	mmc_retune_needed(host);
162 }
163 
164 /**
165  *	mmc_of_parse() - parse host's device-tree node
166  *	@host: host whose node should be parsed.
167  *
168  * To keep the rest of the MMC subsystem unaware of whether DT has been
169  * used to to instantiate and configure this host instance or not, we
170  * parse the properties and set respective generic mmc-host flags and
171  * parameters.
172  */
173 int mmc_of_parse(struct mmc_host *host)
174 {
175 	struct device *dev = host->parent;
176 	u32 bus_width, drv_type, cd_debounce_delay_ms;
177 	int ret;
178 
179 	if (!dev || !dev_fwnode(dev))
180 		return 0;
181 
182 	/* "bus-width" is translated to MMC_CAP_*_BIT_DATA flags */
183 	if (device_property_read_u32(dev, "bus-width", &bus_width) < 0) {
184 		dev_dbg(host->parent,
185 			"\"bus-width\" property is missing, assuming 1 bit.\n");
186 		bus_width = 1;
187 	}
188 
189 	switch (bus_width) {
190 	case 8:
191 		host->caps |= MMC_CAP_8_BIT_DATA;
192 		/* fall through - Hosts capable of 8-bit can also do 4 bits */
193 	case 4:
194 		host->caps |= MMC_CAP_4_BIT_DATA;
195 		break;
196 	case 1:
197 		break;
198 	default:
199 		dev_err(host->parent,
200 			"Invalid \"bus-width\" value %u!\n", bus_width);
201 		return -EINVAL;
202 	}
203 
204 	/* f_max is obtained from the optional "max-frequency" property */
205 	device_property_read_u32(dev, "max-frequency", &host->f_max);
206 
207 	/*
208 	 * Configure CD and WP pins. They are both by default active low to
209 	 * match the SDHCI spec. If GPIOs are provided for CD and / or WP, the
210 	 * mmc-gpio helpers are used to attach, configure and use them. If
211 	 * polarity inversion is specified in DT, one of MMC_CAP2_CD_ACTIVE_HIGH
212 	 * and MMC_CAP2_RO_ACTIVE_HIGH capability-2 flags is set. If the
213 	 * "broken-cd" property is provided, the MMC_CAP_NEEDS_POLL capability
214 	 * is set. If the "non-removable" property is found, the
215 	 * MMC_CAP_NONREMOVABLE capability is set and no card-detection
216 	 * configuration is performed.
217 	 */
218 
219 	/* Parse Card Detection */
220 
221 	if (device_property_read_bool(dev, "non-removable")) {
222 		host->caps |= MMC_CAP_NONREMOVABLE;
223 	} else {
224 		if (device_property_read_bool(dev, "cd-inverted"))
225 			host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
226 
227 		if (device_property_read_u32(dev, "cd-debounce-delay-ms",
228 					     &cd_debounce_delay_ms))
229 			cd_debounce_delay_ms = 200;
230 
231 		if (device_property_read_bool(dev, "broken-cd"))
232 			host->caps |= MMC_CAP_NEEDS_POLL;
233 
234 		ret = mmc_gpiod_request_cd(host, "cd", 0, false,
235 					   cd_debounce_delay_ms * 1000);
236 		if (!ret)
237 			dev_info(host->parent, "Got CD GPIO\n");
238 		else if (ret != -ENOENT && ret != -ENOSYS)
239 			return ret;
240 	}
241 
242 	/* Parse Write Protection */
243 
244 	if (device_property_read_bool(dev, "wp-inverted"))
245 		host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
246 
247 	ret = mmc_gpiod_request_ro(host, "wp", 0, 0);
248 	if (!ret)
249 		dev_info(host->parent, "Got WP GPIO\n");
250 	else if (ret != -ENOENT && ret != -ENOSYS)
251 		return ret;
252 
253 	if (device_property_read_bool(dev, "disable-wp"))
254 		host->caps2 |= MMC_CAP2_NO_WRITE_PROTECT;
255 
256 	if (device_property_read_bool(dev, "cap-sd-highspeed"))
257 		host->caps |= MMC_CAP_SD_HIGHSPEED;
258 	if (device_property_read_bool(dev, "cap-mmc-highspeed"))
259 		host->caps |= MMC_CAP_MMC_HIGHSPEED;
260 	if (device_property_read_bool(dev, "sd-uhs-sdr12"))
261 		host->caps |= MMC_CAP_UHS_SDR12;
262 	if (device_property_read_bool(dev, "sd-uhs-sdr25"))
263 		host->caps |= MMC_CAP_UHS_SDR25;
264 	if (device_property_read_bool(dev, "sd-uhs-sdr50"))
265 		host->caps |= MMC_CAP_UHS_SDR50;
266 	if (device_property_read_bool(dev, "sd-uhs-sdr104"))
267 		host->caps |= MMC_CAP_UHS_SDR104;
268 	if (device_property_read_bool(dev, "sd-uhs-ddr50"))
269 		host->caps |= MMC_CAP_UHS_DDR50;
270 	if (device_property_read_bool(dev, "cap-power-off-card"))
271 		host->caps |= MMC_CAP_POWER_OFF_CARD;
272 	if (device_property_read_bool(dev, "cap-mmc-hw-reset"))
273 		host->caps |= MMC_CAP_HW_RESET;
274 	if (device_property_read_bool(dev, "cap-sdio-irq"))
275 		host->caps |= MMC_CAP_SDIO_IRQ;
276 	if (device_property_read_bool(dev, "full-pwr-cycle"))
277 		host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
278 	if (device_property_read_bool(dev, "keep-power-in-suspend"))
279 		host->pm_caps |= MMC_PM_KEEP_POWER;
280 	if (device_property_read_bool(dev, "wakeup-source") ||
281 	    device_property_read_bool(dev, "enable-sdio-wakeup")) /* legacy */
282 		host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
283 	if (device_property_read_bool(dev, "mmc-ddr-3_3v"))
284 		host->caps |= MMC_CAP_3_3V_DDR;
285 	if (device_property_read_bool(dev, "mmc-ddr-1_8v"))
286 		host->caps |= MMC_CAP_1_8V_DDR;
287 	if (device_property_read_bool(dev, "mmc-ddr-1_2v"))
288 		host->caps |= MMC_CAP_1_2V_DDR;
289 	if (device_property_read_bool(dev, "mmc-hs200-1_8v"))
290 		host->caps2 |= MMC_CAP2_HS200_1_8V_SDR;
291 	if (device_property_read_bool(dev, "mmc-hs200-1_2v"))
292 		host->caps2 |= MMC_CAP2_HS200_1_2V_SDR;
293 	if (device_property_read_bool(dev, "mmc-hs400-1_8v"))
294 		host->caps2 |= MMC_CAP2_HS400_1_8V | MMC_CAP2_HS200_1_8V_SDR;
295 	if (device_property_read_bool(dev, "mmc-hs400-1_2v"))
296 		host->caps2 |= MMC_CAP2_HS400_1_2V | MMC_CAP2_HS200_1_2V_SDR;
297 	if (device_property_read_bool(dev, "mmc-hs400-enhanced-strobe"))
298 		host->caps2 |= MMC_CAP2_HS400_ES;
299 	if (device_property_read_bool(dev, "no-sdio"))
300 		host->caps2 |= MMC_CAP2_NO_SDIO;
301 	if (device_property_read_bool(dev, "no-sd"))
302 		host->caps2 |= MMC_CAP2_NO_SD;
303 	if (device_property_read_bool(dev, "no-mmc"))
304 		host->caps2 |= MMC_CAP2_NO_MMC;
305 
306 	/* Must be after "non-removable" check */
307 	if (device_property_read_u32(dev, "fixed-emmc-driver-type", &drv_type) == 0) {
308 		if (host->caps & MMC_CAP_NONREMOVABLE)
309 			host->fixed_drv_type = drv_type;
310 		else
311 			dev_err(host->parent,
312 				"can't use fixed driver type, media is removable\n");
313 	}
314 
315 	host->dsr_req = !device_property_read_u32(dev, "dsr", &host->dsr);
316 	if (host->dsr_req && (host->dsr & ~0xffff)) {
317 		dev_err(host->parent,
318 			"device tree specified broken value for DSR: 0x%x, ignoring\n",
319 			host->dsr);
320 		host->dsr_req = 0;
321 	}
322 
323 	device_property_read_u32(dev, "post-power-on-delay-ms",
324 				 &host->ios.power_delay_ms);
325 
326 	return mmc_pwrseq_alloc(host);
327 }
328 
329 EXPORT_SYMBOL(mmc_of_parse);
330 
331 /**
332  * mmc_of_parse_voltage - return mask of supported voltages
333  * @np: The device node need to be parsed.
334  * @mask: mask of voltages available for MMC/SD/SDIO
335  *
336  * Parse the "voltage-ranges" DT property, returning zero if it is not
337  * found, negative errno if the voltage-range specification is invalid,
338  * or one if the voltage-range is specified and successfully parsed.
339  */
340 int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
341 {
342 	const u32 *voltage_ranges;
343 	int num_ranges, i;
344 
345 	voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
346 	if (!voltage_ranges) {
347 		pr_debug("%pOF: voltage-ranges unspecified\n", np);
348 		return 0;
349 	}
350 	num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
351 	if (!num_ranges) {
352 		pr_err("%pOF: voltage-ranges empty\n", np);
353 		return -EINVAL;
354 	}
355 
356 	for (i = 0; i < num_ranges; i++) {
357 		const int j = i * 2;
358 		u32 ocr_mask;
359 
360 		ocr_mask = mmc_vddrange_to_ocrmask(
361 				be32_to_cpu(voltage_ranges[j]),
362 				be32_to_cpu(voltage_ranges[j + 1]));
363 		if (!ocr_mask) {
364 			pr_err("%pOF: voltage-range #%d is invalid\n",
365 				np, i);
366 			return -EINVAL;
367 		}
368 		*mask |= ocr_mask;
369 	}
370 
371 	return 1;
372 }
373 EXPORT_SYMBOL(mmc_of_parse_voltage);
374 
375 /**
376  *	mmc_alloc_host - initialise the per-host structure.
377  *	@extra: sizeof private data structure
378  *	@dev: pointer to host device model structure
379  *
380  *	Initialise the per-host structure.
381  */
382 struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
383 {
384 	int err;
385 	struct mmc_host *host;
386 
387 	host = kzalloc(sizeof(struct mmc_host) + extra, GFP_KERNEL);
388 	if (!host)
389 		return NULL;
390 
391 	/* scanning will be enabled when we're ready */
392 	host->rescan_disable = 1;
393 
394 	err = ida_simple_get(&mmc_host_ida, 0, 0, GFP_KERNEL);
395 	if (err < 0) {
396 		kfree(host);
397 		return NULL;
398 	}
399 
400 	host->index = err;
401 
402 	dev_set_name(&host->class_dev, "mmc%d", host->index);
403 
404 	host->parent = dev;
405 	host->class_dev.parent = dev;
406 	host->class_dev.class = &mmc_host_class;
407 	device_initialize(&host->class_dev);
408 	device_enable_async_suspend(&host->class_dev);
409 
410 	if (mmc_gpio_alloc(host)) {
411 		put_device(&host->class_dev);
412 		return NULL;
413 	}
414 
415 	spin_lock_init(&host->lock);
416 	init_waitqueue_head(&host->wq);
417 	INIT_DELAYED_WORK(&host->detect, mmc_rescan);
418 	INIT_DELAYED_WORK(&host->sdio_irq_work, sdio_irq_work);
419 	timer_setup(&host->retune_timer, mmc_retune_timer, 0);
420 
421 	/*
422 	 * By default, hosts do not support SGIO or large requests.
423 	 * They have to set these according to their abilities.
424 	 */
425 	host->max_segs = 1;
426 	host->max_seg_size = PAGE_SIZE;
427 
428 	host->max_req_size = PAGE_SIZE;
429 	host->max_blk_size = 512;
430 	host->max_blk_count = PAGE_SIZE / 512;
431 
432 	host->fixed_drv_type = -EINVAL;
433 	host->ios.power_delay_ms = 10;
434 
435 	return host;
436 }
437 
438 EXPORT_SYMBOL(mmc_alloc_host);
439 
440 /**
441  *	mmc_add_host - initialise host hardware
442  *	@host: mmc host
443  *
444  *	Register the host with the driver model. The host must be
445  *	prepared to start servicing requests before this function
446  *	completes.
447  */
448 int mmc_add_host(struct mmc_host *host)
449 {
450 	int err;
451 
452 	WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) &&
453 		!host->ops->enable_sdio_irq);
454 
455 	err = device_add(&host->class_dev);
456 	if (err)
457 		return err;
458 
459 	led_trigger_register_simple(dev_name(&host->class_dev), &host->led);
460 
461 #ifdef CONFIG_DEBUG_FS
462 	mmc_add_host_debugfs(host);
463 #endif
464 
465 	mmc_start_host(host);
466 	mmc_register_pm_notifier(host);
467 
468 	return 0;
469 }
470 
471 EXPORT_SYMBOL(mmc_add_host);
472 
473 /**
474  *	mmc_remove_host - remove host hardware
475  *	@host: mmc host
476  *
477  *	Unregister and remove all cards associated with this host,
478  *	and power down the MMC bus. No new requests will be issued
479  *	after this function has returned.
480  */
481 void mmc_remove_host(struct mmc_host *host)
482 {
483 	mmc_unregister_pm_notifier(host);
484 	mmc_stop_host(host);
485 
486 #ifdef CONFIG_DEBUG_FS
487 	mmc_remove_host_debugfs(host);
488 #endif
489 
490 	device_del(&host->class_dev);
491 
492 	led_trigger_unregister_simple(host->led);
493 }
494 
495 EXPORT_SYMBOL(mmc_remove_host);
496 
497 /**
498  *	mmc_free_host - free the host structure
499  *	@host: mmc host
500  *
501  *	Free the host once all references to it have been dropped.
502  */
503 void mmc_free_host(struct mmc_host *host)
504 {
505 	mmc_pwrseq_free(host);
506 	put_device(&host->class_dev);
507 }
508 
509 EXPORT_SYMBOL(mmc_free_host);
510