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_platform.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 #include "core.h"
21
22 /* USB WRAPPER register offsets */
23 #define USBSS_PID 0x0
24 #define USBSS_OVERCURRENT_CTRL 0x4
25 #define USBSS_PHY_CONFIG 0x8
26 #define USBSS_PHY_TEST 0xc
27 #define USBSS_CORE_STAT 0x14
28 #define USBSS_HOST_VBUS_CTRL 0x18
29 #define USBSS_MODE_CONTROL 0x1c
30 #define USBSS_WAKEUP_CONFIG 0x30
31 #define USBSS_WAKEUP_STAT 0x34
32 #define USBSS_OVERRIDE_CONFIG 0x38
33 #define USBSS_IRQ_MISC_STATUS_RAW 0x430
34 #define USBSS_IRQ_MISC_STATUS 0x434
35 #define USBSS_IRQ_MISC_ENABLE_SET 0x438
36 #define USBSS_IRQ_MISC_ENABLE_CLR 0x43c
37 #define USBSS_IRQ_MISC_EOI 0x440
38 #define USBSS_INTR_TEST 0x490
39 #define USBSS_VBUS_FILTER 0x614
40 #define USBSS_VBUS_STAT 0x618
41 #define USBSS_DEBUG_CFG 0x708
42 #define USBSS_DEBUG_DATA 0x70c
43 #define USBSS_HOST_HUB_CTRL 0x714
44
45 /* PHY CONFIG register bits */
46 #define USBSS_PHY_VBUS_SEL_MASK GENMASK(2, 1)
47 #define USBSS_PHY_VBUS_SEL_SHIFT 1
48 #define USBSS_PHY_LANE_REVERSE BIT(0)
49
50 /* CORE STAT register bits */
51 #define USBSS_CORE_OPERATIONAL_MODE_MASK GENMASK(13, 12)
52 #define USBSS_CORE_OPERATIONAL_MODE_SHIFT 12
53
54 /* MODE CONTROL register bits */
55 #define USBSS_MODE_VALID BIT(0)
56
57 /* WAKEUP CONFIG register bits */
58 #define USBSS_WAKEUP_CFG_OVERCURRENT_EN BIT(3)
59 #define USBSS_WAKEUP_CFG_LINESTATE_EN BIT(2)
60 #define USBSS_WAKEUP_CFG_SESSVALID_EN BIT(1)
61 #define USBSS_WAKEUP_CFG_VBUSVALID_EN BIT(0)
62
63 #define USBSS_WAKEUP_CFG_ALL (USBSS_WAKEUP_CFG_VBUSVALID_EN | \
64 USBSS_WAKEUP_CFG_SESSVALID_EN | \
65 USBSS_WAKEUP_CFG_LINESTATE_EN | \
66 USBSS_WAKEUP_CFG_OVERCURRENT_EN)
67
68 #define USBSS_WAKEUP_CFG_NONE 0
69
70 /* WAKEUP STAT register bits */
71 #define USBSS_WAKEUP_STAT_OVERCURRENT BIT(4)
72 #define USBSS_WAKEUP_STAT_LINESTATE BIT(3)
73 #define USBSS_WAKEUP_STAT_SESSVALID BIT(2)
74 #define USBSS_WAKEUP_STAT_VBUSVALID BIT(1)
75 #define USBSS_WAKEUP_STAT_CLR BIT(0)
76
77 /* IRQ_MISC_STATUS_RAW register bits */
78 #define USBSS_IRQ_MISC_RAW_VBUSVALID BIT(22)
79 #define USBSS_IRQ_MISC_RAW_SESSVALID BIT(20)
80
81 /* IRQ_MISC_STATUS register bits */
82 #define USBSS_IRQ_MISC_VBUSVALID BIT(22)
83 #define USBSS_IRQ_MISC_SESSVALID BIT(20)
84
85 /* IRQ_MISC_ENABLE_SET register bits */
86 #define USBSS_IRQ_MISC_ENABLE_SET_VBUSVALID BIT(22)
87 #define USBSS_IRQ_MISC_ENABLE_SET_SESSVALID BIT(20)
88
89 /* IRQ_MISC_ENABLE_CLR register bits */
90 #define USBSS_IRQ_MISC_ENABLE_CLR_VBUSVALID BIT(22)
91 #define USBSS_IRQ_MISC_ENABLE_CLR_SESSVALID BIT(20)
92
93 /* IRQ_MISC_EOI register bits */
94 #define USBSS_IRQ_MISC_EOI_VECTOR BIT(0)
95
96 /* VBUS_STAT register bits */
97 #define USBSS_VBUS_STAT_SESSVALID BIT(2)
98 #define USBSS_VBUS_STAT_VBUSVALID BIT(0)
99
100 /* Mask for PHY PLL REFCLK */
101 #define PHY_PLL_REFCLK_MASK GENMASK(3, 0)
102
103 #define DWC3_AM62_AUTOSUSPEND_DELAY 100
104
105 struct dwc3_am62 {
106 struct device *dev;
107 void __iomem *usbss;
108 struct clk *usb2_refclk;
109 int rate_code;
110 struct regmap *syscon;
111 unsigned int offset;
112 unsigned int vbus_divider;
113 u32 wakeup_stat;
114 };
115
116 static const int dwc3_ti_rate_table[] = { /* in KHZ */
117 9600,
118 10000,
119 12000,
120 19200,
121 20000,
122 24000,
123 25000,
124 26000,
125 38400,
126 40000,
127 58000,
128 50000,
129 52000,
130 };
131
dwc3_ti_readl(struct dwc3_am62 * am62,u32 offset)132 static inline u32 dwc3_ti_readl(struct dwc3_am62 *am62, u32 offset)
133 {
134 return readl((am62->usbss) + offset);
135 }
136
dwc3_ti_writel(struct dwc3_am62 * am62,u32 offset,u32 value)137 static inline void dwc3_ti_writel(struct dwc3_am62 *am62, u32 offset, u32 value)
138 {
139 writel(value, (am62->usbss) + offset);
140 }
141
phy_syscon_pll_refclk(struct dwc3_am62 * am62)142 static int phy_syscon_pll_refclk(struct dwc3_am62 *am62)
143 {
144 struct device *dev = am62->dev;
145 struct device_node *node = dev->of_node;
146 struct of_phandle_args args;
147 struct regmap *syscon;
148 int ret;
149
150 syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
151 if (IS_ERR(syscon)) {
152 dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
153 return PTR_ERR(syscon);
154 }
155
156 am62->syscon = syscon;
157
158 ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
159 0, &args);
160 if (ret)
161 return ret;
162
163 am62->offset = args.args[0];
164
165 ret = regmap_update_bits(am62->syscon, am62->offset, PHY_PLL_REFCLK_MASK, am62->rate_code);
166 if (ret) {
167 dev_err(dev, "failed to set phy pll reference clock rate\n");
168 return ret;
169 }
170
171 return 0;
172 }
173
dwc3_ti_probe(struct platform_device * pdev)174 static int dwc3_ti_probe(struct platform_device *pdev)
175 {
176 struct device *dev = &pdev->dev;
177 struct device_node *node = pdev->dev.of_node;
178 struct dwc3_am62 *am62;
179 int i, ret;
180 unsigned long rate;
181 u32 reg;
182
183 am62 = devm_kzalloc(dev, sizeof(*am62), GFP_KERNEL);
184 if (!am62)
185 return -ENOMEM;
186
187 am62->dev = dev;
188 platform_set_drvdata(pdev, am62);
189
190 am62->usbss = devm_platform_ioremap_resource(pdev, 0);
191 if (IS_ERR(am62->usbss)) {
192 dev_err(dev, "can't map IOMEM resource\n");
193 return PTR_ERR(am62->usbss);
194 }
195
196 am62->usb2_refclk = devm_clk_get(dev, "ref");
197 if (IS_ERR(am62->usb2_refclk)) {
198 dev_err(dev, "can't get usb2_refclk\n");
199 return PTR_ERR(am62->usb2_refclk);
200 }
201
202 /* Calculate the rate code */
203 rate = clk_get_rate(am62->usb2_refclk);
204 rate /= 1000; // To KHz
205 for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
206 if (dwc3_ti_rate_table[i] == rate)
207 break;
208 }
209
210 if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
211 dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
212 return -EINVAL;
213 }
214
215 am62->rate_code = i;
216
217 /* Read the syscon property and set the rate code */
218 ret = phy_syscon_pll_refclk(am62);
219 if (ret)
220 return ret;
221
222 /* VBUS divider select */
223 am62->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
224 reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG);
225 if (am62->vbus_divider)
226 reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
227
228 dwc3_ti_writel(am62, USBSS_PHY_CONFIG, reg);
229
230 pm_runtime_set_active(dev);
231 pm_runtime_enable(dev);
232 /*
233 * Don't ignore its dependencies with its children
234 */
235 pm_suspend_ignore_children(dev, false);
236 clk_prepare_enable(am62->usb2_refclk);
237 pm_runtime_get_noresume(dev);
238
239 ret = of_platform_populate(node, NULL, NULL, dev);
240 if (ret) {
241 dev_err(dev, "failed to create dwc3 core: %d\n", ret);
242 goto err_pm_disable;
243 }
244
245 /* Set mode valid bit to indicate role is valid */
246 reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL);
247 reg |= USBSS_MODE_VALID;
248 dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg);
249
250 /* Device has capability to wakeup system from sleep */
251 device_set_wakeup_capable(dev, true);
252 ret = device_wakeup_enable(dev);
253 if (ret)
254 dev_err(dev, "couldn't enable device as a wakeup source: %d\n", ret);
255
256 /* Setting up autosuspend */
257 pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
258 pm_runtime_use_autosuspend(dev);
259 pm_runtime_mark_last_busy(dev);
260 pm_runtime_put_autosuspend(dev);
261 return 0;
262
263 err_pm_disable:
264 clk_disable_unprepare(am62->usb2_refclk);
265 pm_runtime_disable(dev);
266 pm_runtime_set_suspended(dev);
267 return ret;
268 }
269
dwc3_ti_remove(struct platform_device * pdev)270 static void dwc3_ti_remove(struct platform_device *pdev)
271 {
272 struct device *dev = &pdev->dev;
273 struct dwc3_am62 *am62 = platform_get_drvdata(pdev);
274 u32 reg;
275
276 pm_runtime_get_sync(dev);
277 device_init_wakeup(dev, false);
278 of_platform_depopulate(dev);
279
280 /* Clear mode valid bit */
281 reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL);
282 reg &= ~USBSS_MODE_VALID;
283 dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg);
284
285 pm_runtime_put_sync(dev);
286 pm_runtime_disable(dev);
287 pm_runtime_set_suspended(dev);
288 }
289
290 #ifdef CONFIG_PM
dwc3_ti_suspend_common(struct device * dev)291 static int dwc3_ti_suspend_common(struct device *dev)
292 {
293 struct dwc3_am62 *am62 = dev_get_drvdata(dev);
294 u32 reg, current_prtcap_dir;
295
296 if (device_may_wakeup(dev)) {
297 reg = dwc3_ti_readl(am62, USBSS_CORE_STAT);
298 current_prtcap_dir = (reg & USBSS_CORE_OPERATIONAL_MODE_MASK)
299 >> USBSS_CORE_OPERATIONAL_MODE_SHIFT;
300 /* Set wakeup config enable bits */
301 reg = dwc3_ti_readl(am62, USBSS_WAKEUP_CONFIG);
302 if (current_prtcap_dir == DWC3_GCTL_PRTCAP_HOST) {
303 reg = USBSS_WAKEUP_CFG_LINESTATE_EN | USBSS_WAKEUP_CFG_OVERCURRENT_EN;
304 } else {
305 reg = USBSS_WAKEUP_CFG_VBUSVALID_EN | USBSS_WAKEUP_CFG_SESSVALID_EN;
306 /*
307 * Enable LINESTATE wake up only if connected to bus
308 * and in U2/L3 state else it causes spurious wake-up.
309 */
310 }
311 dwc3_ti_writel(am62, USBSS_WAKEUP_CONFIG, reg);
312 /* clear wakeup status so we know what caused the wake up */
313 dwc3_ti_writel(am62, USBSS_WAKEUP_STAT, USBSS_WAKEUP_STAT_CLR);
314 }
315
316 clk_disable_unprepare(am62->usb2_refclk);
317
318 return 0;
319 }
320
dwc3_ti_resume_common(struct device * dev)321 static int dwc3_ti_resume_common(struct device *dev)
322 {
323 struct dwc3_am62 *am62 = dev_get_drvdata(dev);
324 u32 reg;
325
326 clk_prepare_enable(am62->usb2_refclk);
327
328 if (device_may_wakeup(dev)) {
329 /* Clear wakeup config enable bits */
330 dwc3_ti_writel(am62, USBSS_WAKEUP_CONFIG, USBSS_WAKEUP_CFG_NONE);
331 }
332
333 reg = dwc3_ti_readl(am62, USBSS_WAKEUP_STAT);
334 am62->wakeup_stat = reg;
335
336 return 0;
337 }
338
339 static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
340 dwc3_ti_resume_common, NULL);
341
342 #define DEV_PM_OPS (&dwc3_ti_pm_ops)
343 #else
344 #define DEV_PM_OPS NULL
345 #endif /* CONFIG_PM */
346
347 static const struct of_device_id dwc3_ti_of_match[] = {
348 { .compatible = "ti,am62-usb"},
349 {},
350 };
351 MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
352
353 static struct platform_driver dwc3_ti_driver = {
354 .probe = dwc3_ti_probe,
355 .remove_new = dwc3_ti_remove,
356 .driver = {
357 .name = "dwc3-am62",
358 .pm = DEV_PM_OPS,
359 .of_match_table = dwc3_ti_of_match,
360 },
361 };
362
363 module_platform_driver(dwc3_ti_driver);
364
365 MODULE_ALIAS("platform:dwc3-am62");
366 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
367 MODULE_LICENSE("GPL");
368 MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");
369