1// SPDX-License-Identifier: GPL-2.0
2/*
3 * cdns3-starfive.c - StarFive specific Glue layer for Cadence USB Controller
4 *
5 * Copyright (C) 2023 StarFive Technology Co., Ltd.
6 *
7 * Author:	Minda Chen <minda.chen@starfivetech.com>
8 */
9
10#include <linux/bits.h>
11#include <linux/clk.h>
12#include <linux/module.h>
13#include <linux/mfd/syscon.h>
14#include <linux/kernel.h>
15#include <linux/platform_device.h>
16#include <linux/io.h>
17#include <linux/of_platform.h>
18#include <linux/reset.h>
19#include <linux/regmap.h>
20#include <linux/usb/otg.h>
21#include "core.h"
22
23#define USB_STRAP_HOST			BIT(17)
24#define USB_STRAP_DEVICE		BIT(18)
25#define USB_STRAP_MASK			GENMASK(18, 16)
26
27#define USB_SUSPENDM_HOST		BIT(19)
28#define USB_SUSPENDM_MASK		BIT(19)
29
30#define USB_MISC_CFG_MASK		GENMASK(23, 20)
31#define USB_SUSPENDM_BYPS		BIT(20)
32#define USB_PLL_EN			BIT(22)
33#define USB_REFCLK_MODE			BIT(23)
34
35struct cdns_starfive {
36	struct device *dev;
37	struct regmap *stg_syscon;
38	struct reset_control *resets;
39	struct clk_bulk_data *clks;
40	int num_clks;
41	u32 stg_usb_mode;
42};
43
44static void cdns_mode_init(struct platform_device *pdev,
45			   struct cdns_starfive *data)
46{
47	enum usb_dr_mode mode;
48
49	regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
50			   USB_MISC_CFG_MASK,
51			   USB_SUSPENDM_BYPS | USB_PLL_EN | USB_REFCLK_MODE);
52
53	/* dr mode setting */
54	mode = usb_get_dr_mode(&pdev->dev);
55
56	switch (mode) {
57	case USB_DR_MODE_HOST:
58		regmap_update_bits(data->stg_syscon,
59				   data->stg_usb_mode,
60				   USB_STRAP_MASK,
61				   USB_STRAP_HOST);
62		regmap_update_bits(data->stg_syscon,
63				   data->stg_usb_mode,
64				   USB_SUSPENDM_MASK,
65				   USB_SUSPENDM_HOST);
66		break;
67
68	case USB_DR_MODE_PERIPHERAL:
69		regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
70				   USB_STRAP_MASK, USB_STRAP_DEVICE);
71		regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
72				   USB_SUSPENDM_MASK, 0);
73		break;
74	default:
75		break;
76	}
77}
78
79static int cdns_clk_rst_init(struct cdns_starfive *data)
80{
81	int ret;
82
83	ret = clk_bulk_prepare_enable(data->num_clks, data->clks);
84	if (ret)
85		return dev_err_probe(data->dev, ret,
86				     "failed to enable clocks\n");
87
88	ret = reset_control_deassert(data->resets);
89	if (ret) {
90		dev_err(data->dev, "failed to reset clocks\n");
91		goto err_clk_init;
92	}
93
94	return ret;
95
96err_clk_init:
97	clk_bulk_disable_unprepare(data->num_clks, data->clks);
98	return ret;
99}
100
101static void cdns_clk_rst_deinit(struct cdns_starfive *data)
102{
103	reset_control_assert(data->resets);
104	clk_bulk_disable_unprepare(data->num_clks, data->clks);
105}
106
107static int cdns_starfive_probe(struct platform_device *pdev)
108{
109	struct device *dev = &pdev->dev;
110	struct cdns_starfive *data;
111	unsigned int args;
112	int ret;
113
114	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
115	if (!data)
116		return -ENOMEM;
117
118	data->dev = dev;
119
120	data->stg_syscon =
121		syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
122						     "starfive,stg-syscon", 1, &args);
123
124	if (IS_ERR(data->stg_syscon))
125		return dev_err_probe(dev, PTR_ERR(data->stg_syscon),
126				     "Failed to parse starfive,stg-syscon\n");
127
128	data->stg_usb_mode = args;
129
130	data->num_clks = devm_clk_bulk_get_all(data->dev, &data->clks);
131	if (data->num_clks < 0)
132		return dev_err_probe(data->dev, -ENODEV,
133				     "Failed to get clocks\n");
134
135	data->resets = devm_reset_control_array_get_exclusive(data->dev);
136	if (IS_ERR(data->resets))
137		return dev_err_probe(data->dev, PTR_ERR(data->resets),
138				     "Failed to get resets");
139
140	cdns_mode_init(pdev, data);
141	ret = cdns_clk_rst_init(data);
142	if (ret)
143		return ret;
144
145	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
146	if (ret) {
147		dev_err(dev, "Failed to create children\n");
148		cdns_clk_rst_deinit(data);
149		return ret;
150	}
151
152	device_set_wakeup_capable(dev, true);
153	pm_runtime_set_active(dev);
154	pm_runtime_enable(dev);
155	platform_set_drvdata(pdev, data);
156
157	return 0;
158}
159
160static int cdns_starfive_remove_core(struct device *dev, void *c)
161{
162	struct platform_device *pdev = to_platform_device(dev);
163
164	platform_device_unregister(pdev);
165
166	return 0;
167}
168
169static void cdns_starfive_remove(struct platform_device *pdev)
170{
171	struct device *dev = &pdev->dev;
172	struct cdns_starfive *data = dev_get_drvdata(dev);
173
174	pm_runtime_get_sync(dev);
175	device_for_each_child(dev, NULL, cdns_starfive_remove_core);
176
177	pm_runtime_disable(dev);
178	pm_runtime_put_noidle(dev);
179	cdns_clk_rst_deinit(data);
180	platform_set_drvdata(pdev, NULL);
181}
182
183#ifdef CONFIG_PM
184static int cdns_starfive_runtime_resume(struct device *dev)
185{
186	struct cdns_starfive *data = dev_get_drvdata(dev);
187
188	return clk_bulk_prepare_enable(data->num_clks, data->clks);
189}
190
191static int cdns_starfive_runtime_suspend(struct device *dev)
192{
193	struct cdns_starfive *data = dev_get_drvdata(dev);
194
195	clk_bulk_disable_unprepare(data->num_clks, data->clks);
196
197	return 0;
198}
199
200#ifdef CONFIG_PM_SLEEP
201static int cdns_starfive_resume(struct device *dev)
202{
203	struct cdns_starfive *data = dev_get_drvdata(dev);
204
205	return cdns_clk_rst_init(data);
206}
207
208static int cdns_starfive_suspend(struct device *dev)
209{
210	struct cdns_starfive *data = dev_get_drvdata(dev);
211
212	cdns_clk_rst_deinit(data);
213
214	return 0;
215}
216#endif
217#endif
218
219static const struct dev_pm_ops cdns_starfive_pm_ops = {
220	SET_RUNTIME_PM_OPS(cdns_starfive_runtime_suspend,
221			   cdns_starfive_runtime_resume, NULL)
222	SET_SYSTEM_SLEEP_PM_OPS(cdns_starfive_suspend, cdns_starfive_resume)
223};
224
225static const struct of_device_id cdns_starfive_of_match[] = {
226	{ .compatible = "starfive,jh7110-usb", },
227	{ /* sentinel */ }
228};
229MODULE_DEVICE_TABLE(of, cdns_starfive_of_match);
230
231static struct platform_driver cdns_starfive_driver = {
232	.probe		= cdns_starfive_probe,
233	.remove_new	= cdns_starfive_remove,
234	.driver		= {
235		.name	= "cdns3-starfive",
236		.of_match_table	= cdns_starfive_of_match,
237		.pm	= &cdns_starfive_pm_ops,
238	},
239};
240module_platform_driver(cdns_starfive_driver);
241
242MODULE_ALIAS("platform:cdns3-starfive");
243MODULE_LICENSE("GPL v2");
244MODULE_DESCRIPTION("Cadence USB3 StarFive Glue Layer");
245