Free Electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
/*
 * Generic platform ehci driver
 *
 * Copyright 2007 Steven Brown <sbrown@cortland.com>
 * Copyright 2010-2012 Hauke Mehrtens <hauke@hauke-m.de>
 * Copyright 2014 Hans de Goede <hdegoede@redhat.com>
 *
 * Derived from the ohci-ssb driver
 * Copyright 2007 Michael Buesch <m@bues.ch>
 *
 * Derived from the EHCI-PCI driver
 * Copyright (c) 2000-2004 by David Brownell
 *
 * Derived from the ohci-pci driver
 * Copyright 1999 Roman Weissgaerber
 * Copyright 2000-2002 David Brownell
 * Copyright 1999 Linus Torvalds
 * Copyright 1999 Gregory P. Smith
 *
 * Licensed under the GNU/GPL. See COPYING for details.
 */
#include <linux/acpi.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/hrtimer.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/usb/ehci_pdriver.h>
#include <linux/usb/of.h>

#include "ehci.h"

#define DRIVER_DESC "EHCI generic platform driver"
#define EHCI_MAX_CLKS 4
#define EHCI_MAX_RSTS 4
#define hcd_to_ehci_priv(h) ((struct ehci_platform_priv *)hcd_to_ehci(h)->priv)

struct ehci_platform_priv {
	struct clk *clks[EHCI_MAX_CLKS];
	struct reset_control *rsts[EHCI_MAX_RSTS];
	struct phy **phys;
	int num_phys;
	bool reset_on_resume;
};

static const char hcd_name[] = "ehci-platform";

static int ehci_platform_reset(struct usb_hcd *hcd)
{
	struct platform_device *pdev = to_platform_device(hcd->self.controller);
	struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
	int retval;

	ehci->has_synopsys_hc_bug = pdata->has_synopsys_hc_bug;

	if (pdata->pre_setup) {
		retval = pdata->pre_setup(hcd);
		if (retval < 0)
			return retval;
	}

	ehci->caps = hcd->regs + pdata->caps_offset;
	retval = ehci_setup(hcd);
	if (retval)
		return retval;

	if (pdata->no_io_watchdog)
		ehci->need_io_watchdog = 0;
	return 0;
}

static int ehci_platform_power_on(struct platform_device *dev)
{
	struct usb_hcd *hcd = platform_get_drvdata(dev);
	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
	int clk, ret, phy_num;

	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++) {
		ret = clk_prepare_enable(priv->clks[clk]);
		if (ret)
			goto err_disable_clks;
	}

	for (phy_num = 0; phy_num < priv->num_phys; phy_num++) {
		ret = phy_init(priv->phys[phy_num]);
		if (ret)
			goto err_exit_phy;
		ret = phy_power_on(priv->phys[phy_num]);
		if (ret) {
			phy_exit(priv->phys[phy_num]);
			goto err_exit_phy;
		}
	}

	return 0;

err_exit_phy:
	while (--phy_num >= 0) {
		phy_power_off(priv->phys[phy_num]);
		phy_exit(priv->phys[phy_num]);
	}
err_disable_clks:
	while (--clk >= 0)
		clk_disable_unprepare(priv->clks[clk]);

	return ret;
}

static void ehci_platform_power_off(struct platform_device *dev)
{
	struct usb_hcd *hcd = platform_get_drvdata(dev);
	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
	int clk, phy_num;

	for (phy_num = 0; phy_num < priv->num_phys; phy_num++) {
		phy_power_off(priv->phys[phy_num]);
		phy_exit(priv->phys[phy_num]);
	}

	for (clk = EHCI_MAX_CLKS - 1; clk >= 0; clk--)
		if (priv->clks[clk])
			clk_disable_unprepare(priv->clks[clk]);
}

static struct hc_driver __read_mostly ehci_platform_hc_driver;

static const struct ehci_driver_overrides platform_overrides __initconst = {
	.reset =		ehci_platform_reset,
	.extra_priv_size =	sizeof(struct ehci_platform_priv),
};

static struct usb_ehci_pdata ehci_platform_defaults = {
	.power_on =		ehci_platform_power_on,
	.power_suspend =	ehci_platform_power_off,
	.power_off =		ehci_platform_power_off,
};

static int ehci_platform_probe(struct platform_device *dev)
{
	struct usb_hcd *hcd;
	struct resource *res_mem;
	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
	struct ehci_platform_priv *priv;
	struct ehci_hcd *ehci;
	int err, irq, phy_num, clk = 0, rst;

	if (usb_disabled())
		return -ENODEV;

	/*
	 * Use reasonable defaults so platforms don't have to provide these
	 * with DT probing on ARM.
	 */
	if (!pdata)
		pdata = &ehci_platform_defaults;

	err = dma_coerce_mask_and_coherent(&dev->dev,
		pdata->dma_mask_64 ? DMA_BIT_MASK(64) : DMA_BIT_MASK(32));
	if (err) {
		dev_err(&dev->dev, "Error: DMA mask configuration failed\n");
		return err;
	}

	irq = platform_get_irq(dev, 0);
	if (irq < 0) {
		dev_err(&dev->dev, "no irq provided");
		return irq;
	}

	hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
			     dev_name(&dev->dev));
	if (!hcd)
		return -ENOMEM;

	platform_set_drvdata(dev, hcd);
	dev->dev.platform_data = pdata;
	priv = hcd_to_ehci_priv(hcd);
	ehci = hcd_to_ehci(hcd);

	if (pdata == &ehci_platform_defaults && dev->dev.of_node) {
		if (of_property_read_bool(dev->dev.of_node, "big-endian-regs"))
			ehci->big_endian_mmio = 1;

		if (of_property_read_bool(dev->dev.of_node, "big-endian-desc"))
			ehci->big_endian_desc = 1;

		if (of_property_read_bool(dev->dev.of_node, "big-endian"))
			ehci->big_endian_mmio = ehci->big_endian_desc = 1;

		if (of_property_read_bool(dev->dev.of_node,
					  "needs-reset-on-resume"))
			priv->reset_on_resume = true;

		if (of_property_read_bool(dev->dev.of_node,
					  "has-transaction-translator"))
			hcd->has_tt = 1;

		priv->num_phys = of_count_phandle_with_args(dev->dev.of_node,
				"phys", "#phy-cells");

		if (priv->num_phys > 0) {
			priv->phys = devm_kcalloc(&dev->dev, priv->num_phys,
					    sizeof(struct phy *), GFP_KERNEL);
			if (!priv->phys)
				return -ENOMEM;
		} else
			priv->num_phys = 0;

		for (phy_num = 0; phy_num < priv->num_phys; phy_num++) {
			priv->phys[phy_num] = devm_of_phy_get_by_index(
					&dev->dev, dev->dev.of_node, phy_num);
			if (IS_ERR(priv->phys[phy_num])) {
				err = PTR_ERR(priv->phys[phy_num]);
					goto err_put_hcd;
			} else if (!hcd->phy) {
				/* Avoiding phy_get() in usb_add_hcd() */
				hcd->phy = priv->phys[phy_num];
			}
		}

		for (clk = 0; clk < EHCI_MAX_CLKS; clk++) {
			priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
			if (IS_ERR(priv->clks[clk])) {
				err = PTR_ERR(priv->clks[clk]);
				if (err == -EPROBE_DEFER)
					goto err_put_clks;
				priv->clks[clk] = NULL;
				break;
			}
		}
	}

	for (rst = 0; rst < EHCI_MAX_RSTS; rst++) {
		priv->rsts[rst] = devm_reset_control_get_shared_by_index(
					&dev->dev, rst);
		if (IS_ERR(priv->rsts[rst])) {
			err = PTR_ERR(priv->rsts[rst]);
			if (err == -EPROBE_DEFER)
				goto err_reset;
			priv->rsts[rst] = NULL;
			break;
		}

		err = reset_control_deassert(priv->rsts[rst]);
		if (err)
			goto err_reset;
	}

	if (pdata->big_endian_desc)
		ehci->big_endian_desc = 1;
	if (pdata->big_endian_mmio)
		ehci->big_endian_mmio = 1;
	if (pdata->has_tt)
		hcd->has_tt = 1;
	if (pdata->reset_on_resume)
		priv->reset_on_resume = true;

#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
	if (ehci->big_endian_mmio) {
		dev_err(&dev->dev,
			"Error: CONFIG_USB_EHCI_BIG_ENDIAN_MMIO not set\n");
		err = -EINVAL;
		goto err_reset;
	}
#endif
#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_DESC
	if (ehci->big_endian_desc) {
		dev_err(&dev->dev,
			"Error: CONFIG_USB_EHCI_BIG_ENDIAN_DESC not set\n");
		err = -EINVAL;
		goto err_reset;
	}
#endif

	if (pdata->power_on) {
		err = pdata->power_on(dev);
		if (err < 0)
			goto err_reset;
	}

	res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
	hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
	if (IS_ERR(hcd->regs)) {
		err = PTR_ERR(hcd->regs);
		goto err_power;
	}
	hcd->rsrc_start = res_mem->start;
	hcd->rsrc_len = resource_size(res_mem);

	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
	if (err)
		goto err_power;

	device_wakeup_enable(hcd->self.controller);
	device_enable_async_suspend(hcd->self.controller);
	platform_set_drvdata(dev, hcd);

	return err;

err_power:
	if (pdata->power_off)
		pdata->power_off(dev);
err_reset:
	while (--rst >= 0)
		reset_control_assert(priv->rsts[rst]);
err_put_clks:
	while (--clk >= 0)
		clk_put(priv->clks[clk]);
err_put_hcd:
	if (pdata == &ehci_platform_defaults)
		dev->dev.platform_data = NULL;

	usb_put_hcd(hcd);

	return err;
}

static int ehci_platform_remove(struct platform_device *dev)
{
	struct usb_hcd *hcd = platform_get_drvdata(dev);
	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
	int clk, rst;

	usb_remove_hcd(hcd);

	if (pdata->power_off)
		pdata->power_off(dev);

	for (rst = 0; rst < EHCI_MAX_RSTS && priv->rsts[rst]; rst++)
		reset_control_assert(priv->rsts[rst]);

	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++)
		clk_put(priv->clks[clk]);

	usb_put_hcd(hcd);

	if (pdata == &ehci_platform_defaults)
		dev->dev.platform_data = NULL;

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int ehci_platform_suspend(struct device *dev)
{
	struct usb_hcd *hcd = dev_get_drvdata(dev);
	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
	struct platform_device *pdev = to_platform_device(dev);
	bool do_wakeup = device_may_wakeup(dev);
	int ret;

	ret = ehci_suspend(hcd, do_wakeup);
	if (ret)
		return ret;

	if (pdata->power_suspend)
		pdata->power_suspend(pdev);

	return ret;
}

static int ehci_platform_resume(struct device *dev)
{
	struct usb_hcd *hcd = dev_get_drvdata(dev);
	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
	struct platform_device *pdev = to_platform_device(dev);
	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
	struct device *companion_dev;

	if (pdata->power_on) {
		int err = pdata->power_on(pdev);
		if (err < 0)
			return err;
	}

	companion_dev = usb_of_get_companion_dev(hcd->self.controller);
	if (companion_dev) {
		device_pm_wait_for_dev(hcd->self.controller, companion_dev);
		put_device(companion_dev);
	}

	ehci_resume(hcd, priv->reset_on_resume);
	return 0;
}
#endif /* CONFIG_PM_SLEEP */

static const struct of_device_id vt8500_ehci_ids[] = {
	{ .compatible = "via,vt8500-ehci", },
	{ .compatible = "wm,prizm-ehci", },
	{ .compatible = "generic-ehci", },
	{ .compatible = "cavium,octeon-6335-ehci", },
	{}
};
MODULE_DEVICE_TABLE(of, vt8500_ehci_ids);

static const struct acpi_device_id ehci_acpi_match[] = {
	{ "PNP0D20", 0 }, /* EHCI controller without debug */
	{ }
};
MODULE_DEVICE_TABLE(acpi, ehci_acpi_match);

static const struct platform_device_id ehci_platform_table[] = {
	{ "ehci-platform", 0 },
	{ }
};
MODULE_DEVICE_TABLE(platform, ehci_platform_table);

static SIMPLE_DEV_PM_OPS(ehci_platform_pm_ops, ehci_platform_suspend,
	ehci_platform_resume);

static struct platform_driver ehci_platform_driver = {
	.id_table	= ehci_platform_table,
	.probe		= ehci_platform_probe,
	.remove		= ehci_platform_remove,
	.shutdown	= usb_hcd_platform_shutdown,
	.driver		= {
		.name	= "ehci-platform",
		.pm	= &ehci_platform_pm_ops,
		.of_match_table = vt8500_ehci_ids,
		.acpi_match_table = ACPI_PTR(ehci_acpi_match),
	}
};

static int __init ehci_platform_init(void)
{
	if (usb_disabled())
		return -ENODEV;

	pr_info("%s: " DRIVER_DESC "\n", hcd_name);

	ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
	return platform_driver_register(&ehci_platform_driver);
}
module_init(ehci_platform_init);

static void __exit ehci_platform_cleanup(void)
{
	platform_driver_unregister(&ehci_platform_driver);
}
module_exit(ehci_platform_cleanup);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR("Hauke Mehrtens");
MODULE_AUTHOR("Alan Stern");
MODULE_LICENSE("GPL");