1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * dwc3-am62.c - TI specific Glue layer for AM62 DWC3 USB Controller
4 *
5 * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com
6 */
7
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/of.h>
14 #include <linux/of_device.h>
15 #include <linux/pm_runtime.h>
16 #include <linux/clk.h>
17 #include <linux/regmap.h>
18 #include <linux/pinctrl/consumer.h>
19
20 /* USB WRAPPER register offsets */
21 #define USBSS_PID 0x0
22 #define USBSS_OVERCURRENT_CTRL 0x4
23 #define USBSS_PHY_CONFIG 0x8
24 #define USBSS_PHY_TEST 0xc
25 #define USBSS_CORE_STAT 0x14
26 #define USBSS_HOST_VBUS_CTRL 0x18
27 #define USBSS_MODE_CONTROL 0x1c
28 #define USBSS_WAKEUP_CONFIG 0x30
29 #define USBSS_WAKEUP_STAT 0x34
30 #define USBSS_OVERRIDE_CONFIG 0x38
31 #define USBSS_IRQ_MISC_STATUS_RAW 0x430
32 #define USBSS_IRQ_MISC_STATUS 0x434
33 #define USBSS_IRQ_MISC_ENABLE_SET 0x438
34 #define USBSS_IRQ_MISC_ENABLE_CLR 0x43c
35 #define USBSS_IRQ_MISC_EOI 0x440
36 #define USBSS_INTR_TEST 0x490
37 #define USBSS_VBUS_FILTER 0x614
38 #define USBSS_VBUS_STAT 0x618
39 #define USBSS_DEBUG_CFG 0x708
40 #define USBSS_DEBUG_DATA 0x70c
41 #define USBSS_HOST_HUB_CTRL 0x714
42
43 /* PHY CONFIG register bits */
44 #define USBSS_PHY_VBUS_SEL_MASK GENMASK(2, 1)
45 #define USBSS_PHY_VBUS_SEL_SHIFT 1
46 #define USBSS_PHY_LANE_REVERSE BIT(0)
47
48 /* MODE CONTROL register bits */
49 #define USBSS_MODE_VALID BIT(0)
50
51 /* WAKEUP CONFIG register bits */
52 #define USBSS_WAKEUP_CFG_OVERCURRENT_EN BIT(3)
53 #define USBSS_WAKEUP_CFG_LINESTATE_EN BIT(2)
54 #define USBSS_WAKEUP_CFG_SESSVALID_EN BIT(1)
55 #define USBSS_WAKEUP_CFG_VBUSVALID_EN BIT(0)
56
57 /* WAKEUP STAT register bits */
58 #define USBSS_WAKEUP_STAT_OVERCURRENT BIT(4)
59 #define USBSS_WAKEUP_STAT_LINESTATE BIT(3)
60 #define USBSS_WAKEUP_STAT_SESSVALID BIT(2)
61 #define USBSS_WAKEUP_STAT_VBUSVALID BIT(1)
62 #define USBSS_WAKEUP_STAT_CLR BIT(0)
63
64 /* IRQ_MISC_STATUS_RAW register bits */
65 #define USBSS_IRQ_MISC_RAW_VBUSVALID BIT(22)
66 #define USBSS_IRQ_MISC_RAW_SESSVALID BIT(20)
67
68 /* IRQ_MISC_STATUS register bits */
69 #define USBSS_IRQ_MISC_VBUSVALID BIT(22)
70 #define USBSS_IRQ_MISC_SESSVALID BIT(20)
71
72 /* IRQ_MISC_ENABLE_SET register bits */
73 #define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID BIT(22)
74 #define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID BIT(20)
75
76 /* IRQ_MISC_ENABLE_CLR register bits */
77 #define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID BIT(22)
78 #define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID BIT(20)
79
80 /* IRQ_MISC_EOI register bits */
81 #define USBSS_IRQ_MISC_EOI_VECTOR BIT(0)
82
83 /* VBUS_STAT register bits */
84 #define USBSS_VBUS_STAT_SESSVALID BIT(2)
85 #define USBSS_VBUS_STAT_VBUSVALID BIT(0)
86
87 /* Mask for PHY PLL REFCLK */
88 #define PHY_PLL_REFCLK_MASK GENMASK(3, 0)
89
90 #define DWC3_AM62_AUTOSUSPEND_DELAY 100
91
92 struct dwc3_data {
93 struct device *dev;
94 void __iomem *usbss;
95 struct clk *usb2_refclk;
96 int rate_code;
97 struct regmap *syscon;
98 unsigned int offset;
99 unsigned int vbus_divider;
100 };
101
102 static const int dwc3_ti_rate_table[] = { /* in KHZ */
103 9600,
104 10000,
105 12000,
106 19200,
107 20000,
108 24000,
109 25000,
110 26000,
111 38400,
112 40000,
113 58000,
114 50000,
115 52000,
116 };
117
dwc3_ti_readl(struct dwc3_data * data,u32 offset)118 static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
119 {
120 return readl((data->usbss) + offset);
121 }
122
dwc3_ti_writel(struct dwc3_data * data,u32 offset,u32 value)123 static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
124 {
125 writel(value, (data->usbss) + offset);
126 }
127
phy_syscon_pll_refclk(struct dwc3_data * data)128 static int phy_syscon_pll_refclk(struct dwc3_data *data)
129 {
130 struct device *dev = data->dev;
131 struct device_node *node = dev->of_node;
132 struct of_phandle_args args;
133 struct regmap *syscon;
134 int ret;
135
136 syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
137 if (IS_ERR(syscon)) {
138 dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
139 return PTR_ERR(syscon);
140 }
141
142 data->syscon = syscon;
143
144 ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
145 0, &args);
146 if (ret)
147 return ret;
148
149 data->offset = args.args[0];
150
151 ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->rate_code);
152 if (ret) {
153 dev_err(dev, "failed to set phy pll reference clock rate\n");
154 return ret;
155 }
156
157 return 0;
158 }
159
dwc3_ti_probe(struct platform_device * pdev)160 static int dwc3_ti_probe(struct platform_device *pdev)
161 {
162 struct device *dev = &pdev->dev;
163 struct device_node *node = pdev->dev.of_node;
164 struct dwc3_data *data;
165 int i, ret;
166 unsigned long rate;
167 u32 reg;
168
169 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
170 if (!data)
171 return -ENOMEM;
172
173 data->dev = dev;
174 platform_set_drvdata(pdev, data);
175
176 data->usbss = devm_platform_ioremap_resource(pdev, 0);
177 if (IS_ERR(data->usbss)) {
178 dev_err(dev, "can't map IOMEM resource\n");
179 return PTR_ERR(data->usbss);
180 }
181
182 data->usb2_refclk = devm_clk_get(dev, "ref");
183 if (IS_ERR(data->usb2_refclk)) {
184 dev_err(dev, "can't get usb2_refclk\n");
185 return PTR_ERR(data->usb2_refclk);
186 }
187
188 /* Calculate the rate code */
189 rate = clk_get_rate(data->usb2_refclk);
190 rate /= 1000; // To KHz
191 for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
192 if (dwc3_ti_rate_table[i] == rate)
193 break;
194 }
195
196 if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
197 dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
198 return -EINVAL;
199 }
200
201 data->rate_code = i;
202
203 /* Read the syscon property and set the rate code */
204 ret = phy_syscon_pll_refclk(data);
205 if (ret)
206 return ret;
207
208 /* VBUS divider select */
209 data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
210 reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
211 if (data->vbus_divider)
212 reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
213
214 dwc3_ti_writel(data, USBSS_PHY_CONFIG, reg);
215
216 pm_runtime_set_active(dev);
217 pm_runtime_enable(dev);
218 /*
219 * Don't ignore its dependencies with its children
220 */
221 pm_suspend_ignore_children(dev, false);
222 clk_prepare_enable(data->usb2_refclk);
223 pm_runtime_get_noresume(dev);
224
225 ret = of_platform_populate(node, NULL, NULL, dev);
226 if (ret) {
227 dev_err(dev, "failed to create dwc3 core: %d\n", ret);
228 goto err_pm_disable;
229 }
230
231 /* Set mode valid bit to indicate role is valid */
232 reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
233 reg |= USBSS_MODE_VALID;
234 dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
235
236 /* Setting up autosuspend */
237 pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
238 pm_runtime_use_autosuspend(dev);
239 pm_runtime_mark_last_busy(dev);
240 pm_runtime_put_autosuspend(dev);
241 return 0;
242
243 err_pm_disable:
244 clk_disable_unprepare(data->usb2_refclk);
245 pm_runtime_disable(dev);
246 pm_runtime_set_suspended(dev);
247 return ret;
248 }
249
dwc3_ti_remove_core(struct device * dev,void * c)250 static int dwc3_ti_remove_core(struct device *dev, void *c)
251 {
252 struct platform_device *pdev = to_platform_device(dev);
253
254 platform_device_unregister(pdev);
255 return 0;
256 }
257
dwc3_ti_remove(struct platform_device * pdev)258 static int dwc3_ti_remove(struct platform_device *pdev)
259 {
260 struct device *dev = &pdev->dev;
261 struct dwc3_data *data = platform_get_drvdata(pdev);
262 u32 reg;
263
264 device_for_each_child(dev, NULL, dwc3_ti_remove_core);
265
266 /* Clear mode valid bit */
267 reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
268 reg &= ~USBSS_MODE_VALID;
269 dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
270
271 pm_runtime_put_sync(dev);
272 clk_disable_unprepare(data->usb2_refclk);
273 pm_runtime_disable(dev);
274 pm_runtime_set_suspended(dev);
275
276 platform_set_drvdata(pdev, NULL);
277 return 0;
278 }
279
280 #ifdef CONFIG_PM
dwc3_ti_suspend_common(struct device * dev)281 static int dwc3_ti_suspend_common(struct device *dev)
282 {
283 struct dwc3_data *data = dev_get_drvdata(dev);
284
285 clk_disable_unprepare(data->usb2_refclk);
286
287 return 0;
288 }
289
dwc3_ti_resume_common(struct device * dev)290 static int dwc3_ti_resume_common(struct device *dev)
291 {
292 struct dwc3_data *data = dev_get_drvdata(dev);
293
294 clk_prepare_enable(data->usb2_refclk);
295
296 return 0;
297 }
298
299 static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
300 dwc3_ti_resume_common, NULL);
301
302 #define DEV_PM_OPS (&dwc3_ti_pm_ops)
303 #else
304 #define DEV_PM_OPS NULL
305 #endif /* CONFIG_PM */
306
307 static const struct of_device_id dwc3_ti_of_match[] = {
308 { .compatible = "ti,am62-usb"},
309 {},
310 };
311 MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
312
313 static struct platform_driver dwc3_ti_driver = {
314 .probe = dwc3_ti_probe,
315 .remove = dwc3_ti_remove,
316 .driver = {
317 .name = "dwc3-am62",
318 .pm = DEV_PM_OPS,
319 .of_match_table = dwc3_ti_of_match,
320 },
321 };
322
323 module_platform_driver(dwc3_ti_driver);
324
325 MODULE_ALIAS("platform:dwc3-am62");
326 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
327 MODULE_LICENSE("GPL");
328 MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");
329