xref: /linux/drivers/usb/cdns3/cdns3-starfive.c (revision 95f8bf932b46cd5c17c681d67be9234551234eac)
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  
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  
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  
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  
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  
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  
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
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  
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
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  
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