xref: /linux/drivers/usb/cdns3/cdns3-ti.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * cdns3-ti.c - TI specific Glue layer for Cadence USB Controller
4  *
5  * Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com
6  */
7 
8 #include <linux/bits.h>
9 #include <linux/clk.h>
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/interrupt.h>
13 #include <linux/platform_device.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/io.h>
16 #include <linux/of_platform.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/property.h>
19 #include "core.h"
20 
21 /* USB Wrapper register offsets */
22 #define USBSS_PID		0x0
23 #define	USBSS_W1		0x4
24 #define USBSS_STATIC_CONFIG	0x8
25 #define USBSS_PHY_TEST		0xc
26 #define	USBSS_DEBUG_CTRL	0x10
27 #define	USBSS_DEBUG_INFO	0x14
28 #define	USBSS_DEBUG_LINK_STATE	0x18
29 #define	USBSS_DEVICE_CTRL	0x1c
30 
31 /* Wrapper 1 register bits */
32 #define USBSS_W1_PWRUP_RST		BIT(0)
33 #define USBSS_W1_OVERCURRENT_SEL	BIT(8)
34 #define USBSS_W1_MODESTRAP_SEL		BIT(9)
35 #define USBSS_W1_OVERCURRENT		BIT(16)
36 #define USBSS_W1_MODESTRAP_MASK		GENMASK(18, 17)
37 #define USBSS_W1_MODESTRAP_SHIFT	17
38 #define USBSS_W1_USB2_ONLY		BIT(19)
39 
40 /* Static config register bits */
41 #define USBSS1_STATIC_PLL_REF_SEL_MASK	GENMASK(8, 5)
42 #define USBSS1_STATIC_PLL_REF_SEL_SHIFT	5
43 #define USBSS1_STATIC_LOOPBACK_MODE_MASK	GENMASK(4, 3)
44 #define USBSS1_STATIC_LOOPBACK_MODE_SHIFT	3
45 #define USBSS1_STATIC_VBUS_SEL_MASK	GENMASK(2, 1)
46 #define USBSS1_STATIC_VBUS_SEL_SHIFT	1
47 #define USBSS1_STATIC_LANE_REVERSE	BIT(0)
48 
49 /* Modestrap modes */
50 enum modestrap_mode { USBSS_MODESTRAP_MODE_NONE,
51 		      USBSS_MODESTRAP_MODE_HOST,
52 		      USBSS_MODESTRAP_MODE_PERIPHERAL};
53 
54 struct cdns_ti {
55 	struct device *dev;
56 	void __iomem *usbss;
57 	unsigned usb2_only:1;
58 	unsigned vbus_divider:1;
59 	struct clk *usb2_refclk;
60 	struct clk *lpm_clk;
61 };
62 
63 static const int cdns_ti_rate_table[] = {	/* in KHZ */
64 	9600,
65 	10000,
66 	12000,
67 	19200,
68 	20000,
69 	24000,
70 	25000,
71 	26000,
72 	38400,
73 	40000,
74 	58000,
75 	50000,
76 	52000,
77 };
78 
79 static inline u32 cdns_ti_readl(struct cdns_ti *data, u32 offset)
80 {
81 	return readl(data->usbss + offset);
82 }
83 
84 static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value)
85 {
86 	writel(value, data->usbss + offset);
87 }
88 
89 static struct cdns3_platform_data cdns_ti_pdata = {
90 	.quirks = CDNS3_DRD_SUSPEND_RESIDENCY_ENABLE,   /* Errata i2409 */
91 };
92 
93 static const struct of_dev_auxdata cdns_ti_auxdata[] = {
94 	{
95 		.compatible = "cdns,usb3",
96 		.platform_data = &cdns_ti_pdata,
97 	},
98 	{},
99 };
100 
101 static int cdns_ti_probe(struct platform_device *pdev)
102 {
103 	struct device *dev = &pdev->dev;
104 	struct device_node *node = pdev->dev.of_node;
105 	struct cdns_ti *data;
106 	int error;
107 	u32 reg;
108 	int rate_code, i;
109 	unsigned long rate;
110 
111 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
112 	if (!data)
113 		return -ENOMEM;
114 
115 	platform_set_drvdata(pdev, data);
116 
117 	data->dev = dev;
118 
119 	data->usbss = devm_platform_ioremap_resource(pdev, 0);
120 	if (IS_ERR(data->usbss)) {
121 		dev_err(dev, "can't map IOMEM resource\n");
122 		return PTR_ERR(data->usbss);
123 	}
124 
125 	data->usb2_refclk = devm_clk_get(dev, "ref");
126 	if (IS_ERR(data->usb2_refclk)) {
127 		dev_err(dev, "can't get usb2_refclk\n");
128 		return PTR_ERR(data->usb2_refclk);
129 	}
130 
131 	data->lpm_clk = devm_clk_get(dev, "lpm");
132 	if (IS_ERR(data->lpm_clk)) {
133 		dev_err(dev, "can't get lpm_clk\n");
134 		return PTR_ERR(data->lpm_clk);
135 	}
136 
137 	rate = clk_get_rate(data->usb2_refclk);
138 	rate /= 1000;	/* To KHz */
139 	for (i = 0; i < ARRAY_SIZE(cdns_ti_rate_table); i++) {
140 		if (cdns_ti_rate_table[i] == rate)
141 			break;
142 	}
143 
144 	if (i == ARRAY_SIZE(cdns_ti_rate_table)) {
145 		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
146 		return -EINVAL;
147 	}
148 
149 	rate_code = i;
150 
151 	pm_runtime_enable(dev);
152 	error = pm_runtime_get_sync(dev);
153 	if (error < 0) {
154 		dev_err(dev, "pm_runtime_get_sync failed: %d\n", error);
155 		goto err;
156 	}
157 
158 	/* assert RESET */
159 	reg = cdns_ti_readl(data, USBSS_W1);
160 	reg &= ~USBSS_W1_PWRUP_RST;
161 	cdns_ti_writel(data, USBSS_W1, reg);
162 
163 	/* set static config */
164 	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
165 	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
166 	reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
167 
168 	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
169 	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
170 	if (data->vbus_divider)
171 		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
172 
173 	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
174 	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
175 
176 	/* set USB2_ONLY mode if requested */
177 	reg = cdns_ti_readl(data, USBSS_W1);
178 	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
179 	if (data->usb2_only)
180 		reg |= USBSS_W1_USB2_ONLY;
181 
182 	/* set default modestrap */
183 	reg |= USBSS_W1_MODESTRAP_SEL;
184 	reg &= ~USBSS_W1_MODESTRAP_MASK;
185 	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
186 	cdns_ti_writel(data, USBSS_W1, reg);
187 
188 	/* de-assert RESET */
189 	reg |= USBSS_W1_PWRUP_RST;
190 	cdns_ti_writel(data, USBSS_W1, reg);
191 
192 	error = of_platform_populate(node, NULL, cdns_ti_auxdata, dev);
193 	if (error) {
194 		dev_err(dev, "failed to create children: %d\n", error);
195 		goto err;
196 	}
197 
198 	return 0;
199 
200 err:
201 	pm_runtime_put_sync(data->dev);
202 	pm_runtime_disable(data->dev);
203 
204 	return error;
205 }
206 
207 static int cdns_ti_remove_core(struct device *dev, void *c)
208 {
209 	struct platform_device *pdev = to_platform_device(dev);
210 
211 	platform_device_unregister(pdev);
212 
213 	return 0;
214 }
215 
216 static void cdns_ti_remove(struct platform_device *pdev)
217 {
218 	struct device *dev = &pdev->dev;
219 
220 	device_for_each_child(dev, NULL, cdns_ti_remove_core);
221 	pm_runtime_put_sync(dev);
222 	pm_runtime_disable(dev);
223 
224 	platform_set_drvdata(pdev, NULL);
225 }
226 
227 static const struct of_device_id cdns_ti_of_match[] = {
228 	{ .compatible = "ti,j721e-usb", },
229 	{ .compatible = "ti,am64-usb", },
230 	{},
231 };
232 MODULE_DEVICE_TABLE(of, cdns_ti_of_match);
233 
234 static struct platform_driver cdns_ti_driver = {
235 	.probe		= cdns_ti_probe,
236 	.remove		= cdns_ti_remove,
237 	.driver		= {
238 		.name	= "cdns3-ti",
239 		.of_match_table	= cdns_ti_of_match,
240 	},
241 };
242 
243 module_platform_driver(cdns_ti_driver);
244 
245 MODULE_ALIAS("platform:cdns3-ti");
246 MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
247 MODULE_LICENSE("GPL v2");
248 MODULE_DESCRIPTION("Cadence USB3 TI Glue Layer");
249