1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * omap-usb2.c - USB PHY, talking to USB controller on TI SoCs.
4 *
5 * Copyright (C) 2012-2020 Texas Instruments Incorporated - http://www.ti.com
6 * Author: Kishon Vijay Abraham I <kishon@ti.com>
7 */
8
9#include <linux/clk.h>
10#include <linux/delay.h>
11#include <linux/err.h>
12#include <linux/io.h>
13#include <linux/mfd/syscon.h>
14#include <linux/module.h>
15#include <linux/of.h>
16#include <linux/of_platform.h>
17#include <linux/phy/omap_control_phy.h>
18#include <linux/phy/omap_usb.h>
19#include <linux/phy/phy.h>
20#include <linux/platform_device.h>
21#include <linux/pm_runtime.h>
22#include <linux/property.h>
23#include <linux/regmap.h>
24#include <linux/slab.h>
25#include <linux/sys_soc.h>
26#include <linux/usb/phy_companion.h>
27
28#define USB2PHY_ANA_CONFIG1		0x4c
29#define USB2PHY_DISCON_BYP_LATCH	BIT(31)
30
31#define USB2PHY_CHRG_DET			0x14
32#define USB2PHY_CHRG_DET_USE_CHG_DET_REG	BIT(29)
33#define USB2PHY_CHRG_DET_DIS_CHG_DET		BIT(28)
34
35/* SoC Specific USB2_OTG register definitions */
36#define AM654_USB2_OTG_PD		BIT(8)
37#define AM654_USB2_VBUS_DET_EN		BIT(5)
38#define AM654_USB2_VBUSVALID_DET_EN	BIT(4)
39
40#define OMAP_DEV_PHY_PD		BIT(0)
41#define OMAP_USB2_PHY_PD	BIT(28)
42
43#define AM437X_USB2_PHY_PD		BIT(0)
44#define AM437X_USB2_OTG_PD		BIT(1)
45#define AM437X_USB2_OTGVDET_EN		BIT(19)
46#define AM437X_USB2_OTGSESSEND_EN	BIT(20)
47
48/* Driver Flags */
49#define OMAP_USB2_HAS_START_SRP			BIT(0)
50#define OMAP_USB2_HAS_SET_VBUS			BIT(1)
51#define OMAP_USB2_CALIBRATE_FALSE_DISCONNECT	BIT(2)
52#define OMAP_USB2_DISABLE_CHRG_DET		BIT(3)
53
54struct omap_usb {
55	struct usb_phy		phy;
56	struct phy_companion	*comparator;
57	void __iomem		*pll_ctrl_base;
58	void __iomem		*phy_base;
59	struct device		*dev;
60	struct device		*control_dev;
61	struct clk		*wkupclk;
62	struct clk		*optclk;
63	u8			flags;
64	struct regmap		*syscon_phy_power; /* ctrl. reg. acces */
65	unsigned int		power_reg; /* power reg. index within syscon */
66	u32			mask;
67	u32			power_on;
68	u32			power_off;
69};
70
71#define	phy_to_omapusb(x)	container_of((x), struct omap_usb, phy)
72
73struct usb_phy_data {
74	const char *label;
75	u8 flags;
76	u32 mask;
77	u32 power_on;
78	u32 power_off;
79};
80
81static inline u32 omap_usb_readl(void __iomem *addr, unsigned int offset)
82{
83	return __raw_readl(addr + offset);
84}
85
86static inline void omap_usb_writel(void __iomem *addr, unsigned int offset,
87				   u32 data)
88{
89	__raw_writel(data, addr + offset);
90}
91
92/**
93 * omap_usb2_set_comparator() - links the comparator present in the system with this phy
94 *
95 * @comparator:  the companion phy(comparator) for this phy
96 *
97 * The phy companion driver should call this API passing the phy_companion
98 * filled with set_vbus and start_srp to be used by usb phy.
99 *
100 * For use by phy companion driver
101 */
102int omap_usb2_set_comparator(struct phy_companion *comparator)
103{
104	struct omap_usb	*phy;
105	struct usb_phy	*x = usb_get_phy(USB_PHY_TYPE_USB2);
106
107	if (IS_ERR(x))
108		return -ENODEV;
109
110	phy = phy_to_omapusb(x);
111	phy->comparator = comparator;
112	return 0;
113}
114EXPORT_SYMBOL_GPL(omap_usb2_set_comparator);
115
116static int omap_usb_set_vbus(struct usb_otg *otg, bool enabled)
117{
118	struct omap_usb *phy = phy_to_omapusb(otg->usb_phy);
119
120	if (!phy->comparator || !phy->comparator->set_vbus)
121		return -ENODEV;
122
123	return phy->comparator->set_vbus(phy->comparator, enabled);
124}
125
126static int omap_usb_start_srp(struct usb_otg *otg)
127{
128	struct omap_usb *phy = phy_to_omapusb(otg->usb_phy);
129
130	if (!phy->comparator || !phy->comparator->start_srp)
131		return -ENODEV;
132
133	return phy->comparator->start_srp(phy->comparator);
134}
135
136static int omap_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
137{
138	otg->host = host;
139	if (!host)
140		otg->state = OTG_STATE_UNDEFINED;
141
142	return 0;
143}
144
145static int omap_usb_set_peripheral(struct usb_otg *otg,
146				   struct usb_gadget *gadget)
147{
148	otg->gadget = gadget;
149	if (!gadget)
150		otg->state = OTG_STATE_UNDEFINED;
151
152	return 0;
153}
154
155static int omap_usb_phy_power(struct omap_usb *phy, int on)
156{
157	u32 val;
158	int ret;
159
160	if (!phy->syscon_phy_power) {
161		omap_control_phy_power(phy->control_dev, on);
162		return 0;
163	}
164
165	if (on)
166		val = phy->power_on;
167	else
168		val = phy->power_off;
169
170	ret = regmap_update_bits(phy->syscon_phy_power, phy->power_reg,
171				 phy->mask, val);
172	return ret;
173}
174
175static int omap_usb_power_off(struct phy *x)
176{
177	struct omap_usb *phy = phy_get_drvdata(x);
178
179	return omap_usb_phy_power(phy, false);
180}
181
182static int omap_usb_power_on(struct phy *x)
183{
184	struct omap_usb *phy = phy_get_drvdata(x);
185
186	return omap_usb_phy_power(phy, true);
187}
188
189static int omap_usb2_disable_clocks(struct omap_usb *phy)
190{
191	clk_disable_unprepare(phy->wkupclk);
192	if (!IS_ERR(phy->optclk))
193		clk_disable_unprepare(phy->optclk);
194
195	return 0;
196}
197
198static int omap_usb2_enable_clocks(struct omap_usb *phy)
199{
200	int ret;
201
202	ret = clk_prepare_enable(phy->wkupclk);
203	if (ret < 0) {
204		dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
205		goto err0;
206	}
207
208	if (!IS_ERR(phy->optclk)) {
209		ret = clk_prepare_enable(phy->optclk);
210		if (ret < 0) {
211			dev_err(phy->dev, "Failed to enable optclk %d\n", ret);
212			goto err1;
213		}
214	}
215
216	return 0;
217
218err1:
219	clk_disable_unprepare(phy->wkupclk);
220
221err0:
222	return ret;
223}
224
225static int omap_usb_init(struct phy *x)
226{
227	struct omap_usb *phy = phy_get_drvdata(x);
228	u32 val;
229
230	omap_usb2_enable_clocks(phy);
231
232	if (phy->flags & OMAP_USB2_CALIBRATE_FALSE_DISCONNECT) {
233		/*
234		 *
235		 * Reduce the sensitivity of internal PHY by enabling the
236		 * DISCON_BYP_LATCH of the USB2PHY_ANA_CONFIG1 register. This
237		 * resolves issues with certain devices which can otherwise
238		 * be prone to false disconnects.
239		 *
240		 */
241		val = omap_usb_readl(phy->phy_base, USB2PHY_ANA_CONFIG1);
242		val |= USB2PHY_DISCON_BYP_LATCH;
243		omap_usb_writel(phy->phy_base, USB2PHY_ANA_CONFIG1, val);
244	}
245
246	if (phy->flags & OMAP_USB2_DISABLE_CHRG_DET) {
247		val = omap_usb_readl(phy->phy_base, USB2PHY_CHRG_DET);
248		val |= USB2PHY_CHRG_DET_USE_CHG_DET_REG |
249		       USB2PHY_CHRG_DET_DIS_CHG_DET;
250		omap_usb_writel(phy->phy_base, USB2PHY_CHRG_DET, val);
251	}
252
253	return 0;
254}
255
256static int omap_usb_exit(struct phy *x)
257{
258	struct omap_usb *phy = phy_get_drvdata(x);
259
260	return omap_usb2_disable_clocks(phy);
261}
262
263static const struct phy_ops ops = {
264	.init		= omap_usb_init,
265	.exit		= omap_usb_exit,
266	.power_on	= omap_usb_power_on,
267	.power_off	= omap_usb_power_off,
268	.owner		= THIS_MODULE,
269};
270
271static const struct usb_phy_data omap_usb2_data = {
272	.label = "omap_usb2",
273	.flags = OMAP_USB2_HAS_START_SRP | OMAP_USB2_HAS_SET_VBUS,
274	.mask = OMAP_DEV_PHY_PD,
275	.power_off = OMAP_DEV_PHY_PD,
276};
277
278static const struct usb_phy_data omap5_usb2_data = {
279	.label = "omap5_usb2",
280	.flags = 0,
281	.mask = OMAP_DEV_PHY_PD,
282	.power_off = OMAP_DEV_PHY_PD,
283};
284
285static const struct usb_phy_data dra7x_usb2_data = {
286	.label = "dra7x_usb2",
287	.flags = OMAP_USB2_CALIBRATE_FALSE_DISCONNECT,
288	.mask = OMAP_DEV_PHY_PD,
289	.power_off = OMAP_DEV_PHY_PD,
290};
291
292static const struct usb_phy_data dra7x_usb2_phy2_data = {
293	.label = "dra7x_usb2_phy2",
294	.flags = OMAP_USB2_CALIBRATE_FALSE_DISCONNECT,
295	.mask = OMAP_USB2_PHY_PD,
296	.power_off = OMAP_USB2_PHY_PD,
297};
298
299static const struct usb_phy_data am437x_usb2_data = {
300	.label = "am437x_usb2",
301	.flags =  0,
302	.mask = AM437X_USB2_PHY_PD | AM437X_USB2_OTG_PD |
303		AM437X_USB2_OTGVDET_EN | AM437X_USB2_OTGSESSEND_EN,
304	.power_on = AM437X_USB2_OTGVDET_EN | AM437X_USB2_OTGSESSEND_EN,
305	.power_off = AM437X_USB2_PHY_PD | AM437X_USB2_OTG_PD,
306};
307
308static const struct usb_phy_data am654_usb2_data = {
309	.label = "am654_usb2",
310	.flags = OMAP_USB2_CALIBRATE_FALSE_DISCONNECT,
311	.mask = AM654_USB2_OTG_PD | AM654_USB2_VBUS_DET_EN |
312		AM654_USB2_VBUSVALID_DET_EN,
313	.power_on = AM654_USB2_VBUS_DET_EN | AM654_USB2_VBUSVALID_DET_EN,
314	.power_off = AM654_USB2_OTG_PD,
315};
316
317static const struct of_device_id omap_usb2_id_table[] = {
318	{
319		.compatible = "ti,omap-usb2",
320		.data = &omap_usb2_data,
321	},
322	{
323		.compatible = "ti,omap5-usb2",
324		.data = &omap5_usb2_data,
325	},
326	{
327		.compatible = "ti,dra7x-usb2",
328		.data = &dra7x_usb2_data,
329	},
330	{
331		.compatible = "ti,dra7x-usb2-phy2",
332		.data = &dra7x_usb2_phy2_data,
333	},
334	{
335		.compatible = "ti,am437x-usb2",
336		.data = &am437x_usb2_data,
337	},
338	{
339		.compatible = "ti,am654-usb2",
340		.data = &am654_usb2_data,
341	},
342	{},
343};
344MODULE_DEVICE_TABLE(of, omap_usb2_id_table);
345
346static void omap_usb2_init_errata(struct omap_usb *phy)
347{
348	static const struct soc_device_attribute am65x_sr10_soc_devices[] = {
349		{ .family = "AM65X", .revision = "SR1.0" },
350		{ /* sentinel */ }
351	};
352
353	/*
354	 * Errata i2075: USB2PHY: USB2PHY Charger Detect is Enabled by
355	 * Default Without VBUS Presence.
356	 *
357	 * AM654x SR1.0 has a silicon bug due to which D+ is pulled high after
358	 * POR, which could cause enumeration failure with some USB hubs.
359	 * Disabling the USB2_PHY Charger Detect function will put D+
360	 * into the normal state.
361	 */
362	if (soc_device_match(am65x_sr10_soc_devices))
363		phy->flags |= OMAP_USB2_DISABLE_CHRG_DET;
364}
365
366static int omap_usb2_probe(struct platform_device *pdev)
367{
368	struct omap_usb	*phy;
369	struct phy *generic_phy;
370	struct phy_provider *phy_provider;
371	struct usb_otg *otg;
372	struct device_node *node = pdev->dev.of_node;
373	struct device_node *control_node;
374	struct platform_device *control_pdev;
375	const struct usb_phy_data *phy_data;
376
377	phy_data = device_get_match_data(&pdev->dev);
378	if (!phy_data)
379		return -EINVAL;
380
381	phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
382	if (!phy)
383		return -ENOMEM;
384
385	otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
386	if (!otg)
387		return -ENOMEM;
388
389	phy->dev		= &pdev->dev;
390
391	phy->phy.dev		= phy->dev;
392	phy->phy.label		= phy_data->label;
393	phy->phy.otg		= otg;
394	phy->phy.type		= USB_PHY_TYPE_USB2;
395	phy->mask		= phy_data->mask;
396	phy->power_on		= phy_data->power_on;
397	phy->power_off		= phy_data->power_off;
398	phy->flags		= phy_data->flags;
399
400	omap_usb2_init_errata(phy);
401
402	phy->phy_base = devm_platform_ioremap_resource(pdev, 0);
403	if (IS_ERR(phy->phy_base))
404		return PTR_ERR(phy->phy_base);
405
406	phy->syscon_phy_power = syscon_regmap_lookup_by_phandle(node,
407								"syscon-phy-power");
408	if (IS_ERR(phy->syscon_phy_power)) {
409		dev_dbg(&pdev->dev,
410			"can't get syscon-phy-power, using control device\n");
411		phy->syscon_phy_power = NULL;
412
413		control_node = of_parse_phandle(node, "ctrl-module", 0);
414		if (!control_node) {
415			dev_err(&pdev->dev,
416				"Failed to get control device phandle\n");
417			return -EINVAL;
418		}
419
420		control_pdev = of_find_device_by_node(control_node);
421		if (!control_pdev) {
422			dev_err(&pdev->dev, "Failed to get control device\n");
423			return -EINVAL;
424		}
425		phy->control_dev = &control_pdev->dev;
426	} else {
427		if (of_property_read_u32_index(node,
428					       "syscon-phy-power", 1,
429					       &phy->power_reg)) {
430			dev_err(&pdev->dev,
431				"couldn't get power reg. offset\n");
432			return -EINVAL;
433		}
434	}
435
436	phy->wkupclk = devm_clk_get(phy->dev, "wkupclk");
437	if (IS_ERR(phy->wkupclk)) {
438		if (PTR_ERR(phy->wkupclk) == -EPROBE_DEFER)
439			return -EPROBE_DEFER;
440
441		dev_warn(&pdev->dev, "unable to get wkupclk %ld, trying old name\n",
442			 PTR_ERR(phy->wkupclk));
443		phy->wkupclk = devm_clk_get(phy->dev, "usb_phy_cm_clk32k");
444
445		if (IS_ERR(phy->wkupclk))
446			return dev_err_probe(&pdev->dev, PTR_ERR(phy->wkupclk),
447					     "unable to get usb_phy_cm_clk32k\n");
448
449		dev_warn(&pdev->dev,
450			 "found usb_phy_cm_clk32k, please fix DTS\n");
451	}
452
453	phy->optclk = devm_clk_get(phy->dev, "refclk");
454	if (IS_ERR(phy->optclk)) {
455		if (PTR_ERR(phy->optclk) == -EPROBE_DEFER)
456			return -EPROBE_DEFER;
457
458		dev_dbg(&pdev->dev, "unable to get refclk, trying old name\n");
459		phy->optclk = devm_clk_get(phy->dev, "usb_otg_ss_refclk960m");
460
461		if (IS_ERR(phy->optclk)) {
462			if (PTR_ERR(phy->optclk) != -EPROBE_DEFER) {
463				dev_dbg(&pdev->dev,
464					"unable to get usb_otg_ss_refclk960m\n");
465			}
466		} else {
467			dev_warn(&pdev->dev,
468				 "found usb_otg_ss_refclk960m, please fix DTS\n");
469		}
470	}
471
472	otg->set_host = omap_usb_set_host;
473	otg->set_peripheral = omap_usb_set_peripheral;
474	if (phy_data->flags & OMAP_USB2_HAS_SET_VBUS)
475		otg->set_vbus = omap_usb_set_vbus;
476	if (phy_data->flags & OMAP_USB2_HAS_START_SRP)
477		otg->start_srp = omap_usb_start_srp;
478	otg->usb_phy = &phy->phy;
479
480	platform_set_drvdata(pdev, phy);
481	pm_runtime_enable(phy->dev);
482
483	generic_phy = devm_phy_create(phy->dev, NULL, &ops);
484	if (IS_ERR(generic_phy)) {
485		pm_runtime_disable(phy->dev);
486		return PTR_ERR(generic_phy);
487	}
488
489	phy_set_drvdata(generic_phy, phy);
490	omap_usb_power_off(generic_phy);
491
492	phy_provider = devm_of_phy_provider_register(phy->dev,
493						     of_phy_simple_xlate);
494	if (IS_ERR(phy_provider)) {
495		pm_runtime_disable(phy->dev);
496		return PTR_ERR(phy_provider);
497	}
498
499	usb_add_phy_dev(&phy->phy);
500
501	return 0;
502}
503
504static void omap_usb2_remove(struct platform_device *pdev)
505{
506	struct omap_usb	*phy = platform_get_drvdata(pdev);
507
508	usb_remove_phy(&phy->phy);
509	pm_runtime_disable(phy->dev);
510}
511
512static struct platform_driver omap_usb2_driver = {
513	.probe		= omap_usb2_probe,
514	.remove_new	= omap_usb2_remove,
515	.driver		= {
516		.name	= "omap-usb2",
517		.of_match_table = omap_usb2_id_table,
518	},
519};
520
521module_platform_driver(omap_usb2_driver);
522
523MODULE_ALIAS("platform:omap_usb2");
524MODULE_AUTHOR("Texas Instruments Inc.");
525MODULE_DESCRIPTION("OMAP USB2 phy driver");
526MODULE_LICENSE("GPL v2");
527