Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.1.
  1// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
  2/*
  3 * platform.c - DesignWare HS OTG Controller platform driver
  4 *
  5 * Copyright (C) Matthijs Kooijman <matthijs@stdin.nl>
  6 *
  7 * Redistribution and use in source and binary forms, with or without
  8 * modification, are permitted provided that the following conditions
  9 * are met:
 10 * 1. Redistributions of source code must retain the above copyright
 11 *    notice, this list of conditions, and the following disclaimer,
 12 *    without modification.
 13 * 2. Redistributions in binary form must reproduce the above copyright
 14 *    notice, this list of conditions and the following disclaimer in the
 15 *    documentation and/or other materials provided with the distribution.
 16 * 3. The names of the above-listed copyright holders may not be used
 17 *    to endorse or promote products derived from this software without
 18 *    specific prior written permission.
 19 *
 20 * ALTERNATIVELY, this software may be distributed under the terms of the
 21 * GNU General Public License ("GPL") as published by the Free Software
 22 * Foundation; either version 2 of the License, or (at your option) any
 23 * later version.
 24 *
 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 26 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 27 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 29 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 30 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 32 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 33 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 34 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 35 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 36 */
 37
 38#include <linux/kernel.h>
 39#include <linux/module.h>
 40#include <linux/slab.h>
 41#include <linux/clk.h>
 42#include <linux/device.h>
 43#include <linux/dma-mapping.h>
 44#include <linux/of_device.h>
 45#include <linux/mutex.h>
 46#include <linux/platform_device.h>
 47#include <linux/phy/phy.h>
 48#include <linux/platform_data/s3c-hsotg.h>
 49#include <linux/reset.h>
 50
 51#include <linux/usb/of.h>
 52
 53#include "core.h"
 54#include "hcd.h"
 55#include "debug.h"
 56
 57static const char dwc2_driver_name[] = "dwc2";
 58
 59/*
 60 * Check the dr_mode against the module configuration and hardware
 61 * capabilities.
 62 *
 63 * The hardware, module, and dr_mode, can each be set to host, device,
 64 * or otg. Check that all these values are compatible and adjust the
 65 * value of dr_mode if possible.
 66 *
 67 *                      actual
 68 *    HW  MOD dr_mode   dr_mode
 69 *  ------------------------------
 70 *   HST  HST  any    :  HST
 71 *   HST  DEV  any    :  ---
 72 *   HST  OTG  any    :  HST
 73 *
 74 *   DEV  HST  any    :  ---
 75 *   DEV  DEV  any    :  DEV
 76 *   DEV  OTG  any    :  DEV
 77 *
 78 *   OTG  HST  any    :  HST
 79 *   OTG  DEV  any    :  DEV
 80 *   OTG  OTG  any    :  dr_mode
 81 */
 82static int dwc2_get_dr_mode(struct dwc2_hsotg *hsotg)
 83{
 84	enum usb_dr_mode mode;
 85
 86	hsotg->dr_mode = usb_get_dr_mode(hsotg->dev);
 87	if (hsotg->dr_mode == USB_DR_MODE_UNKNOWN)
 88		hsotg->dr_mode = USB_DR_MODE_OTG;
 89
 90	mode = hsotg->dr_mode;
 91
 92	if (dwc2_hw_is_device(hsotg)) {
 93		if (IS_ENABLED(CONFIG_USB_DWC2_HOST)) {
 94			dev_err(hsotg->dev,
 95				"Controller does not support host mode.\n");
 96			return -EINVAL;
 97		}
 98		mode = USB_DR_MODE_PERIPHERAL;
 99	} else if (dwc2_hw_is_host(hsotg)) {
100		if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL)) {
101			dev_err(hsotg->dev,
102				"Controller does not support device mode.\n");
103			return -EINVAL;
104		}
105		mode = USB_DR_MODE_HOST;
106	} else {
107		if (IS_ENABLED(CONFIG_USB_DWC2_HOST))
108			mode = USB_DR_MODE_HOST;
109		else if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL))
110			mode = USB_DR_MODE_PERIPHERAL;
111	}
112
113	if (mode != hsotg->dr_mode) {
114		dev_warn(hsotg->dev,
115			 "Configuration mismatch. dr_mode forced to %s\n",
116			mode == USB_DR_MODE_HOST ? "host" : "device");
117
118		hsotg->dr_mode = mode;
119	}
120
121	return 0;
122}
123
124static int __dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
125{
126	struct platform_device *pdev = to_platform_device(hsotg->dev);
127	int ret;
128
129	ret = regulator_bulk_enable(ARRAY_SIZE(hsotg->supplies),
130				    hsotg->supplies);
131	if (ret)
132		return ret;
133
134	if (hsotg->clk) {
135		ret = clk_prepare_enable(hsotg->clk);
136		if (ret)
137			return ret;
138	}
139
140	if (hsotg->uphy) {
141		ret = usb_phy_init(hsotg->uphy);
142	} else if (hsotg->plat && hsotg->plat->phy_init) {
143		ret = hsotg->plat->phy_init(pdev, hsotg->plat->phy_type);
144	} else {
145		ret = phy_power_on(hsotg->phy);
146		if (ret == 0)
147			ret = phy_init(hsotg->phy);
148	}
149
150	return ret;
151}
152
153/**
154 * dwc2_lowlevel_hw_enable - enable platform lowlevel hw resources
155 * @hsotg: The driver state
156 *
157 * A wrapper for platform code responsible for controlling
158 * low-level USB platform resources (phy, clock, regulators)
159 */
160int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
161{
162	int ret = __dwc2_lowlevel_hw_enable(hsotg);
163
164	if (ret == 0)
165		hsotg->ll_hw_enabled = true;
166	return ret;
167}
168
169static int __dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
170{
171	struct platform_device *pdev = to_platform_device(hsotg->dev);
172	int ret = 0;
173
174	if (hsotg->uphy) {
175		usb_phy_shutdown(hsotg->uphy);
176	} else if (hsotg->plat && hsotg->plat->phy_exit) {
177		ret = hsotg->plat->phy_exit(pdev, hsotg->plat->phy_type);
178	} else {
179		ret = phy_exit(hsotg->phy);
180		if (ret == 0)
181			ret = phy_power_off(hsotg->phy);
182	}
183	if (ret)
184		return ret;
185
186	if (hsotg->clk)
187		clk_disable_unprepare(hsotg->clk);
188
189	ret = regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies),
190				     hsotg->supplies);
191
192	return ret;
193}
194
195/**
196 * dwc2_lowlevel_hw_disable - disable platform lowlevel hw resources
197 * @hsotg: The driver state
198 *
199 * A wrapper for platform code responsible for controlling
200 * low-level USB platform resources (phy, clock, regulators)
201 */
202int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
203{
204	int ret = __dwc2_lowlevel_hw_disable(hsotg);
205
206	if (ret == 0)
207		hsotg->ll_hw_enabled = false;
208	return ret;
209}
210
211static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
212{
213	int i, ret;
214
215	hsotg->reset = devm_reset_control_get_optional(hsotg->dev, "dwc2");
216	if (IS_ERR(hsotg->reset)) {
217		ret = PTR_ERR(hsotg->reset);
218		dev_err(hsotg->dev, "error getting reset control %d\n", ret);
219		return ret;
220	}
221
222	reset_control_deassert(hsotg->reset);
223
224	hsotg->reset_ecc = devm_reset_control_get_optional(hsotg->dev, "dwc2-ecc");
225	if (IS_ERR(hsotg->reset_ecc)) {
226		ret = PTR_ERR(hsotg->reset_ecc);
227		dev_err(hsotg->dev, "error getting reset control for ecc %d\n", ret);
228		return ret;
229	}
230
231	reset_control_deassert(hsotg->reset_ecc);
232
233	/*
234	 * Attempt to find a generic PHY, then look for an old style
235	 * USB PHY and then fall back to pdata
236	 */
237	hsotg->phy = devm_phy_get(hsotg->dev, "usb2-phy");
238	if (IS_ERR(hsotg->phy)) {
239		ret = PTR_ERR(hsotg->phy);
240		switch (ret) {
241		case -ENODEV:
242		case -ENOSYS:
243			hsotg->phy = NULL;
244			break;
245		case -EPROBE_DEFER:
246			return ret;
247		default:
248			dev_err(hsotg->dev, "error getting phy %d\n", ret);
249			return ret;
250		}
251	}
252
253	if (!hsotg->phy) {
254		hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2);
255		if (IS_ERR(hsotg->uphy)) {
256			ret = PTR_ERR(hsotg->uphy);
257			switch (ret) {
258			case -ENODEV:
259			case -ENXIO:
260				hsotg->uphy = NULL;
261				break;
262			case -EPROBE_DEFER:
263				return ret;
264			default:
265				dev_err(hsotg->dev, "error getting usb phy %d\n",
266					ret);
267				return ret;
268			}
269		}
270	}
271
272	hsotg->plat = dev_get_platdata(hsotg->dev);
273
274	/* Clock */
275	hsotg->clk = devm_clk_get_optional(hsotg->dev, "otg");
276	if (IS_ERR(hsotg->clk)) {
277		dev_err(hsotg->dev, "cannot get otg clock\n");
278		return PTR_ERR(hsotg->clk);
279	}
280
281	/* Regulators */
282	for (i = 0; i < ARRAY_SIZE(hsotg->supplies); i++)
283		hsotg->supplies[i].supply = dwc2_hsotg_supply_names[i];
284
285	ret = devm_regulator_bulk_get(hsotg->dev, ARRAY_SIZE(hsotg->supplies),
286				      hsotg->supplies);
287	if (ret) {
288		dev_err(hsotg->dev, "failed to request supplies: %d\n", ret);
289		return ret;
290	}
291	return 0;
292}
293
294/**
295 * dwc2_driver_remove() - Called when the DWC_otg core is unregistered with the
296 * DWC_otg driver
297 *
298 * @dev: Platform device
299 *
300 * This routine is called, for example, when the rmmod command is executed. The
301 * device may or may not be electrically present. If it is present, the driver
302 * stops device processing. Any resources used on behalf of this device are
303 * freed.
304 */
305static int dwc2_driver_remove(struct platform_device *dev)
306{
307	struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
308
309	dwc2_debugfs_exit(hsotg);
310	if (hsotg->hcd_enabled)
311		dwc2_hcd_remove(hsotg);
312	if (hsotg->gadget_enabled)
313		dwc2_hsotg_remove(hsotg);
314
315	if (hsotg->ll_hw_enabled)
316		dwc2_lowlevel_hw_disable(hsotg);
317
318	reset_control_assert(hsotg->reset);
319	reset_control_assert(hsotg->reset_ecc);
320
321	return 0;
322}
323
324/**
325 * dwc2_driver_shutdown() - Called on device shutdown
326 *
327 * @dev: Platform device
328 *
329 * In specific conditions (involving usb hubs) dwc2 devices can create a
330 * lot of interrupts, even to the point of overwhelming devices running
331 * at low frequencies. Some devices need to do special clock handling
332 * at shutdown-time which may bring the system clock below the threshold
333 * of being able to handle the dwc2 interrupts. Disabling dwc2-irqs
334 * prevents reboots/poweroffs from getting stuck in such cases.
335 */
336static void dwc2_driver_shutdown(struct platform_device *dev)
337{
338	struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
339
340	disable_irq(hsotg->irq);
341}
342
343/**
344 * dwc2_check_core_endianness() - Returns true if core and AHB have
345 * opposite endianness.
346 * @hsotg:	Programming view of the DWC_otg controller.
347 */
348static bool dwc2_check_core_endianness(struct dwc2_hsotg *hsotg)
349{
350	u32 snpsid;
351
352	snpsid = ioread32(hsotg->regs + GSNPSID);
353	if ((snpsid & GSNPSID_ID_MASK) == DWC2_OTG_ID ||
354	    (snpsid & GSNPSID_ID_MASK) == DWC2_FS_IOT_ID ||
355	    (snpsid & GSNPSID_ID_MASK) == DWC2_HS_IOT_ID)
356		return false;
357	return true;
358}
359
360/**
361 * dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg
362 * driver
363 *
364 * @dev: Platform device
365 *
366 * This routine creates the driver components required to control the device
367 * (core, HCD, and PCD) and initializes the device. The driver components are
368 * stored in a dwc2_hsotg structure. A reference to the dwc2_hsotg is saved
369 * in the device private data. This allows the driver to access the dwc2_hsotg
370 * structure on subsequent calls to driver methods for this device.
371 */
372static int dwc2_driver_probe(struct platform_device *dev)
373{
374	struct dwc2_hsotg *hsotg;
375	struct resource *res;
376	int retval;
377
378	hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL);
379	if (!hsotg)
380		return -ENOMEM;
381
382	hsotg->dev = &dev->dev;
383
384	/*
385	 * Use reasonable defaults so platforms don't have to provide these.
386	 */
387	if (!dev->dev.dma_mask)
388		dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
389	retval = dma_set_coherent_mask(&dev->dev, DMA_BIT_MASK(32));
390	if (retval) {
391		dev_err(&dev->dev, "can't set coherent DMA mask: %d\n", retval);
392		return retval;
393	}
394
395	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
396	hsotg->regs = devm_ioremap_resource(&dev->dev, res);
397	if (IS_ERR(hsotg->regs))
398		return PTR_ERR(hsotg->regs);
399
400	dev_dbg(&dev->dev, "mapped PA %08lx to VA %p\n",
401		(unsigned long)res->start, hsotg->regs);
402
403	retval = dwc2_lowlevel_hw_init(hsotg);
404	if (retval)
405		return retval;
406
407	spin_lock_init(&hsotg->lock);
408
409	hsotg->irq = platform_get_irq(dev, 0);
410	if (hsotg->irq < 0)
411		return hsotg->irq;
412
413	dev_dbg(hsotg->dev, "registering common handler for irq%d\n",
414		hsotg->irq);
415	retval = devm_request_irq(hsotg->dev, hsotg->irq,
416				  dwc2_handle_common_intr, IRQF_SHARED,
417				  dev_name(hsotg->dev), hsotg);
418	if (retval)
419		return retval;
420
421	hsotg->vbus_supply = devm_regulator_get_optional(hsotg->dev, "vbus");
422	if (IS_ERR(hsotg->vbus_supply)) {
423		retval = PTR_ERR(hsotg->vbus_supply);
424		hsotg->vbus_supply = NULL;
425		if (retval != -ENODEV)
426			return retval;
427	}
428
429	retval = dwc2_lowlevel_hw_enable(hsotg);
430	if (retval)
431		return retval;
432
433	hsotg->needs_byte_swap = dwc2_check_core_endianness(hsotg);
434
435	retval = dwc2_get_dr_mode(hsotg);
436	if (retval)
437		goto error;
438
439	hsotg->need_phy_for_wake =
440		of_property_read_bool(dev->dev.of_node,
441				      "snps,need-phy-for-wake");
442
443	/*
444	 * Reset before dwc2_get_hwparams() then it could get power-on real
445	 * reset value form registers.
446	 */
447	retval = dwc2_core_reset(hsotg, false);
448	if (retval)
449		goto error;
450
451	/* Detect config values from hardware */
452	retval = dwc2_get_hwparams(hsotg);
453	if (retval)
454		goto error;
455
456	/*
457	 * For OTG cores, set the force mode bits to reflect the value
458	 * of dr_mode. Force mode bits should not be touched at any
459	 * other time after this.
460	 */
461	dwc2_force_dr_mode(hsotg);
462
463	retval = dwc2_init_params(hsotg);
464	if (retval)
465		goto error;
466
467	if (hsotg->dr_mode != USB_DR_MODE_HOST) {
468		retval = dwc2_gadget_init(hsotg);
469		if (retval)
470			goto error;
471		hsotg->gadget_enabled = 1;
472	}
473
474	/*
475	 * If we need PHY for wakeup we must be wakeup capable.
476	 * When we have a device that can wake without the PHY we
477	 * can adjust this condition.
478	 */
479	if (hsotg->need_phy_for_wake)
480		device_set_wakeup_capable(&dev->dev, true);
481
482	hsotg->reset_phy_on_wake =
483		of_property_read_bool(dev->dev.of_node,
484				      "snps,reset-phy-on-wake");
485	if (hsotg->reset_phy_on_wake && !hsotg->phy) {
486		dev_warn(hsotg->dev,
487			 "Quirk reset-phy-on-wake only supports generic PHYs\n");
488		hsotg->reset_phy_on_wake = false;
489	}
490
491	if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) {
492		retval = dwc2_hcd_init(hsotg);
493		if (retval) {
494			if (hsotg->gadget_enabled)
495				dwc2_hsotg_remove(hsotg);
496			goto error;
497		}
498		hsotg->hcd_enabled = 1;
499	}
500
501	platform_set_drvdata(dev, hsotg);
502	hsotg->hibernated = 0;
503
504	dwc2_debugfs_init(hsotg);
505
506	/* Gadget code manages lowlevel hw on its own */
507	if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
508		dwc2_lowlevel_hw_disable(hsotg);
509
510	return 0;
511
512error:
513	dwc2_lowlevel_hw_disable(hsotg);
514	return retval;
515}
516
517static int __maybe_unused dwc2_suspend(struct device *dev)
518{
519	struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
520	bool is_device_mode = dwc2_is_device_mode(dwc2);
521	int ret = 0;
522
523	if (is_device_mode)
524		dwc2_hsotg_suspend(dwc2);
525
526	if (dwc2->ll_hw_enabled &&
527	    (is_device_mode || dwc2_host_can_poweroff_phy(dwc2))) {
528		ret = __dwc2_lowlevel_hw_disable(dwc2);
529		dwc2->phy_off_for_suspend = true;
530	}
531
532	return ret;
533}
534
535static int __maybe_unused dwc2_resume(struct device *dev)
536{
537	struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
538	int ret = 0;
539
540	if (dwc2->phy_off_for_suspend && dwc2->ll_hw_enabled) {
541		ret = __dwc2_lowlevel_hw_enable(dwc2);
542		if (ret)
543			return ret;
544	}
545	dwc2->phy_off_for_suspend = false;
546
547	if (dwc2_is_device_mode(dwc2))
548		ret = dwc2_hsotg_resume(dwc2);
549
550	return ret;
551}
552
553static const struct dev_pm_ops dwc2_dev_pm_ops = {
554	SET_SYSTEM_SLEEP_PM_OPS(dwc2_suspend, dwc2_resume)
555};
556
557static struct platform_driver dwc2_platform_driver = {
558	.driver = {
559		.name = dwc2_driver_name,
560		.of_match_table = dwc2_of_match_table,
561		.pm = &dwc2_dev_pm_ops,
562	},
563	.probe = dwc2_driver_probe,
564	.remove = dwc2_driver_remove,
565	.shutdown = dwc2_driver_shutdown,
566};
567
568module_platform_driver(dwc2_platform_driver);
569
570MODULE_DESCRIPTION("DESIGNWARE HS OTG Platform Glue");
571MODULE_AUTHOR("Matthijs Kooijman <matthijs@stdin.nl>");
572MODULE_LICENSE("Dual BSD/GPL");