Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  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
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 * TI DA8xx (OMAP-L1x) Bus Glue
 *
 * Derived from: ohci-omap.c and ohci-s3c2410.c
 * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com>
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 */

#include <linux/clk.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_data/usb-davinci.h>
#include <linux/regulator/consumer.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <asm/unaligned.h>

#include "ohci.h"

#define DRIVER_DESC "DA8XX"
#define DRV_NAME "ohci-da8xx"

static struct hc_driver __read_mostly ohci_da8xx_hc_driver;

static int (*orig_ohci_hub_control)(struct usb_hcd  *hcd, u16 typeReq,
			u16 wValue, u16 wIndex, char *buf, u16 wLength);
static int (*orig_ohci_hub_status_data)(struct usb_hcd *hcd, char *buf);

struct da8xx_ohci_hcd {
	struct usb_hcd *hcd;
	struct clk *usb11_clk;
	struct phy *usb11_phy;
	struct regulator *vbus_reg;
	struct notifier_block nb;
	unsigned int reg_enabled;
};

#define to_da8xx_ohci(hcd) (struct da8xx_ohci_hcd *)(hcd_to_ohci(hcd)->priv)

/* Over-current indicator change bitmask */
static volatile u16 ocic_mask;

static int ohci_da8xx_enable(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	int ret;

	ret = clk_prepare_enable(da8xx_ohci->usb11_clk);
	if (ret)
		return ret;

	ret = phy_init(da8xx_ohci->usb11_phy);
	if (ret)
		goto err_phy_init;

	ret = phy_power_on(da8xx_ohci->usb11_phy);
	if (ret)
		goto err_phy_power_on;

	return 0;

err_phy_power_on:
	phy_exit(da8xx_ohci->usb11_phy);
err_phy_init:
	clk_disable_unprepare(da8xx_ohci->usb11_clk);

	return ret;
}

static void ohci_da8xx_disable(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);

	phy_power_off(da8xx_ohci->usb11_phy);
	phy_exit(da8xx_ohci->usb11_phy);
	clk_disable_unprepare(da8xx_ohci->usb11_clk);
}

static int ohci_da8xx_set_power(struct usb_hcd *hcd, int on)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);
	int ret;

	if (hub && hub->set_power)
		return hub->set_power(1, on);

	if (!da8xx_ohci->vbus_reg)
		return 0;

	if (on && !da8xx_ohci->reg_enabled) {
		ret = regulator_enable(da8xx_ohci->vbus_reg);
		if (ret) {
			dev_err(dev, "Failed to enable regulator: %d\n", ret);
			return ret;
		}
		da8xx_ohci->reg_enabled = 1;

	} else if (!on && da8xx_ohci->reg_enabled) {
		ret = regulator_disable(da8xx_ohci->vbus_reg);
		if (ret) {
			dev_err(dev, "Failed  to disable regulator: %d\n", ret);
			return ret;
		}
		da8xx_ohci->reg_enabled = 0;
	}

	return 0;
}

static int ohci_da8xx_get_power(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);

	if (hub && hub->get_power)
		return hub->get_power(1);

	if (da8xx_ohci->vbus_reg)
		return regulator_is_enabled(da8xx_ohci->vbus_reg);

	return 1;
}

static int ohci_da8xx_get_oci(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);
	unsigned int flags;
	int ret;

	if (hub && hub->get_oci)
		return hub->get_oci(1);

	if (!da8xx_ohci->vbus_reg)
		return 0;

	ret = regulator_get_error_flags(da8xx_ohci->vbus_reg, &flags);
	if (ret)
		return ret;

	if (flags & REGULATOR_ERROR_OVER_CURRENT)
		return 1;

	return 0;
}

static int ohci_da8xx_has_set_power(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);

	if (hub && hub->set_power)
		return 1;

	if (da8xx_ohci->vbus_reg)
		return 1;

	return 0;
}

static int ohci_da8xx_has_oci(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);

	if (hub && hub->get_oci)
		return 1;

	if (da8xx_ohci->vbus_reg)
		return 1;

	return 0;
}

static int ohci_da8xx_has_potpgt(struct usb_hcd *hcd)
{
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);

	if (hub && hub->potpgt)
		return 1;

	return 0;
}

/*
 * Handle the port over-current indicator change.
 */
static void ohci_da8xx_ocic_handler(struct da8xx_ohci_root_hub *hub,
				    unsigned port)
{
	ocic_mask |= 1 << port;

	/* Once over-current is detected, the port needs to be powered down */
	if (hub->get_oci(port) > 0)
		hub->set_power(port, 0);
}

static int ohci_da8xx_regulator_event(struct notifier_block *nb,
				unsigned long event, void *data)
{
	struct da8xx_ohci_hcd *da8xx_ohci =
				container_of(nb, struct da8xx_ohci_hcd, nb);

	if (event & REGULATOR_EVENT_OVER_CURRENT) {
		ocic_mask |= 1 << 1;
		ohci_da8xx_set_power(da8xx_ohci->hcd, 0);
	}

	return 0;
}

static int ohci_da8xx_register_notify(struct usb_hcd *hcd)
{
	struct da8xx_ohci_hcd *da8xx_ohci = to_da8xx_ohci(hcd);
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);
	int ret = 0;

	if (hub && hub->ocic_notify) {
		ret = hub->ocic_notify(ohci_da8xx_ocic_handler);
	} else if (da8xx_ohci->vbus_reg) {
		da8xx_ohci->nb.notifier_call = ohci_da8xx_regulator_event;
		ret = devm_regulator_register_notifier(da8xx_ohci->vbus_reg,
						&da8xx_ohci->nb);
	}

	if (ret)
		dev_err(dev, "Failed to register notifier: %d\n", ret);

	return ret;
}

static void ohci_da8xx_unregister_notify(struct usb_hcd *hcd)
{
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);

	if (hub && hub->ocic_notify)
		hub->ocic_notify(NULL);
}

static int ohci_da8xx_reset(struct usb_hcd *hcd)
{
	struct device *dev		= hcd->self.controller;
	struct da8xx_ohci_root_hub *hub	= dev_get_platdata(dev);
	struct ohci_hcd	*ohci		= hcd_to_ohci(hcd);
	int result;
	u32 rh_a;

	dev_dbg(dev, "starting USB controller\n");

	result = ohci_da8xx_enable(hcd);
	if (result < 0)
		return result;

	/*
	 * DA8xx only have 1 port connected to the pins but the HC root hub
	 * register A reports 2 ports, thus we'll have to override it...
	 */
	ohci->num_ports = 1;

	result = ohci_setup(hcd);
	if (result < 0) {
		ohci_da8xx_disable(hcd);
		return result;
	}

	/*
	 * Since we're providing a board-specific root hub port power control
	 * and over-current reporting, we have to override the HC root hub A
	 * register's default value, so that ohci_hub_control() could return
	 * the correct hub descriptor...
	 */
	rh_a = ohci_readl(ohci, &ohci->regs->roothub.a);
	if (ohci_da8xx_has_set_power(hcd)) {
		rh_a &= ~RH_A_NPS;
		rh_a |=  RH_A_PSM;
	}
	if (ohci_da8xx_has_oci(hcd)) {
		rh_a &= ~RH_A_NOCP;
		rh_a |=  RH_A_OCPM;
	}
	if (ohci_da8xx_has_potpgt(hcd)) {
		rh_a &= ~RH_A_POTPGT;
		rh_a |= hub->potpgt << 24;
	}
	ohci_writel(ohci, rh_a, &ohci->regs->roothub.a);

	return result;
}

/*
 * Update the status data from the hub with the over-current indicator change.
 */
static int ohci_da8xx_hub_status_data(struct usb_hcd *hcd, char *buf)
{
	int length		= orig_ohci_hub_status_data(hcd, buf);

	/* See if we have OCIC bit set on port 1 */
	if (ocic_mask & (1 << 1)) {
		dev_dbg(hcd->self.controller, "over-current indicator change "
			"on port 1\n");

		if (!length)
			length = 1;

		buf[0] |= 1 << 1;
	}
	return length;
}

/*
 * Look at the control requests to the root hub and see if we need to override.
 */
static int ohci_da8xx_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
				  u16 wIndex, char *buf, u16 wLength)
{
	struct device *dev		= hcd->self.controller;
	int temp;

	switch (typeReq) {
	case GetPortStatus:
		/* Check the port number */
		if (wIndex != 1)
			break;

		dev_dbg(dev, "GetPortStatus(%u)\n", wIndex);

		temp = roothub_portstatus(hcd_to_ohci(hcd), wIndex - 1);

		/* The port power status (PPS) bit defaults to 1 */
		if (!ohci_da8xx_get_power(hcd))
			temp &= ~RH_PS_PPS;

		/* The port over-current indicator (POCI) bit is always 0 */
		if (ohci_da8xx_get_oci(hcd) > 0)
			temp |=  RH_PS_POCI;

		/* The over-current indicator change (OCIC) bit is 0 too */
		if (ocic_mask & (1 << wIndex))
			temp |=  RH_PS_OCIC;

		put_unaligned(cpu_to_le32(temp), (__le32 *)buf);
		return 0;
	case SetPortFeature:
		temp = 1;
		goto check_port;
	case ClearPortFeature:
		temp = 0;

check_port:
		/* Check the port number */
		if (wIndex != 1)
			break;

		switch (wValue) {
		case USB_PORT_FEAT_POWER:
			dev_dbg(dev, "%sPortFeature(%u): %s\n",
				temp ? "Set" : "Clear", wIndex, "POWER");

			return ohci_da8xx_set_power(hcd, temp) ? -EPIPE : 0;
		case USB_PORT_FEAT_C_OVER_CURRENT:
			dev_dbg(dev, "%sPortFeature(%u): %s\n",
				temp ? "Set" : "Clear", wIndex,
				"C_OVER_CURRENT");

			if (temp)
				ocic_mask |= 1 << wIndex;
			else
				ocic_mask &= ~(1 << wIndex);
			return 0;
		}
	}

	return orig_ohci_hub_control(hcd, typeReq, wValue,
			wIndex, buf, wLength);
}

/*-------------------------------------------------------------------------*/
#ifdef CONFIG_OF
static const struct of_device_id da8xx_ohci_ids[] = {
	{ .compatible = "ti,da830-ohci" },
	{ }
};
MODULE_DEVICE_TABLE(of, da8xx_ohci_ids);
#endif

static int ohci_da8xx_probe(struct platform_device *pdev)
{
	struct da8xx_ohci_hcd *da8xx_ohci;
	struct usb_hcd	*hcd;
	struct resource *mem;
	int error, irq;
	hcd = usb_create_hcd(&ohci_da8xx_hc_driver, &pdev->dev,
				dev_name(&pdev->dev));
	if (!hcd)
		return -ENOMEM;

	da8xx_ohci = to_da8xx_ohci(hcd);
	da8xx_ohci->hcd = hcd;

	da8xx_ohci->usb11_clk = devm_clk_get(&pdev->dev, "usb11");
	if (IS_ERR(da8xx_ohci->usb11_clk)) {
		error = PTR_ERR(da8xx_ohci->usb11_clk);
		if (error != -EPROBE_DEFER)
			dev_err(&pdev->dev, "Failed to get clock.\n");
		goto err;
	}

	da8xx_ohci->usb11_phy = devm_phy_get(&pdev->dev, "usb-phy");
	if (IS_ERR(da8xx_ohci->usb11_phy)) {
		error = PTR_ERR(da8xx_ohci->usb11_phy);
		if (error != -EPROBE_DEFER)
			dev_err(&pdev->dev, "Failed to get phy.\n");
		goto err;
	}

	da8xx_ohci->vbus_reg = devm_regulator_get_optional(&pdev->dev, "vbus");
	if (IS_ERR(da8xx_ohci->vbus_reg)) {
		error = PTR_ERR(da8xx_ohci->vbus_reg);
		if (error == -ENODEV) {
			da8xx_ohci->vbus_reg = NULL;
		} else if (error == -EPROBE_DEFER) {
			goto err;
		} else {
			dev_err(&pdev->dev, "Failed to get regulator\n");
			goto err;
		}
	}

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

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		error = -ENODEV;
		goto err;
	}

	error = usb_add_hcd(hcd, irq, 0);
	if (error)
		goto err;

	device_wakeup_enable(hcd->self.controller);

	error = ohci_da8xx_register_notify(hcd);
	if (error)
		goto err_remove_hcd;

	return 0;

err_remove_hcd:
	usb_remove_hcd(hcd);
err:
	usb_put_hcd(hcd);
	return error;
}

static int ohci_da8xx_remove(struct platform_device *pdev)
{
	struct usb_hcd	*hcd = platform_get_drvdata(pdev);

	ohci_da8xx_unregister_notify(hcd);
	usb_remove_hcd(hcd);
	usb_put_hcd(hcd);

	return 0;
}

#ifdef CONFIG_PM
static int ohci_da8xx_suspend(struct platform_device *pdev,
				pm_message_t message)
{
	struct usb_hcd	*hcd	= platform_get_drvdata(pdev);
	struct ohci_hcd	*ohci	= hcd_to_ohci(hcd);
	bool		do_wakeup	= device_may_wakeup(&pdev->dev);
	int		ret;


	if (time_before(jiffies, ohci->next_statechange))
		msleep(5);
	ohci->next_statechange = jiffies;

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

	ohci_da8xx_disable(hcd);
	hcd->state = HC_STATE_SUSPENDED;

	return ret;
}

static int ohci_da8xx_resume(struct platform_device *dev)
{
	struct usb_hcd	*hcd	= platform_get_drvdata(dev);
	struct ohci_hcd	*ohci	= hcd_to_ohci(hcd);
	int ret;

	if (time_before(jiffies, ohci->next_statechange))
		msleep(5);
	ohci->next_statechange = jiffies;

	ret = ohci_da8xx_enable(hcd);
	if (ret)
		return ret;

	ohci_resume(hcd, false);

	return 0;
}
#endif

static const struct ohci_driver_overrides da8xx_overrides __initconst = {
	.reset		 = ohci_da8xx_reset,
	.extra_priv_size = sizeof(struct da8xx_ohci_hcd),
};

/*
 * Driver definition to register with platform structure.
 */
static struct platform_driver ohci_hcd_da8xx_driver = {
	.probe		= ohci_da8xx_probe,
	.remove		= ohci_da8xx_remove,
	.shutdown 	= usb_hcd_platform_shutdown,
#ifdef	CONFIG_PM
	.suspend	= ohci_da8xx_suspend,
	.resume		= ohci_da8xx_resume,
#endif
	.driver		= {
		.name	= DRV_NAME,
		.of_match_table = of_match_ptr(da8xx_ohci_ids),
	},
};

static int __init ohci_da8xx_init(void)
{

	if (usb_disabled())
		return -ENODEV;

	pr_info("%s: " DRIVER_DESC "\n", DRV_NAME);
	ohci_init_driver(&ohci_da8xx_hc_driver, &da8xx_overrides);

	/*
	 * The Davinci da8xx HW has some unusual quirks, which require
	 * da8xx-specific workarounds. We override certain hc_driver
	 * functions here to achieve that. We explicitly do not enhance
	 * ohci_driver_overrides to allow this more easily, since this
	 * is an unusual case, and we don't want to encourage others to
	 * override these functions by making it too easy.
	 */

	orig_ohci_hub_control = ohci_da8xx_hc_driver.hub_control;
	orig_ohci_hub_status_data = ohci_da8xx_hc_driver.hub_status_data;

	ohci_da8xx_hc_driver.hub_status_data     = ohci_da8xx_hub_status_data;
	ohci_da8xx_hc_driver.hub_control         = ohci_da8xx_hub_control;

	return platform_driver_register(&ohci_hcd_da8xx_driver);
}
module_init(ohci_da8xx_init);

static void __exit ohci_da8xx_exit(void)
{
	platform_driver_unregister(&ohci_hcd_da8xx_driver);
}
module_exit(ohci_da8xx_exit);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);