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
35 struct 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
cdns_mode_init(struct platform_device * pdev,struct cdns_starfive * data)44 static 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
cdns_clk_rst_init(struct cdns_starfive * data)79 static 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
96 err_clk_init:
97 clk_bulk_disable_unprepare(data->num_clks, data->clks);
98 return ret;
99 }
100
cdns_clk_rst_deinit(struct cdns_starfive * data)101 static 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
cdns_starfive_probe(struct platform_device * pdev)107 static 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
cdns_starfive_remove_core(struct device * dev,void * c)160 static 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
cdns_starfive_remove(struct platform_device * pdev)169 static 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
cdns_starfive_runtime_resume(struct device * dev)184 static 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
cdns_starfive_runtime_suspend(struct device * dev)191 static 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
cdns_starfive_resume(struct device * dev)201 static 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
cdns_starfive_suspend(struct device * dev)208 static 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
219 static 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
225 static const struct of_device_id cdns_starfive_of_match[] = {
226 { .compatible = "starfive,jh7110-usb", },
227 { /* sentinel */ }
228 };
229 MODULE_DEVICE_TABLE(of, cdns_starfive_of_match);
230
231 static 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 };
240 module_platform_driver(cdns_starfive_driver);
241
242 MODULE_ALIAS("platform:cdns3-starfive");
243 MODULE_LICENSE("GPL v2");
244 MODULE_DESCRIPTION("Cadence USB3 StarFive Glue Layer");
245