tjh.dev
Linux kernel mirror (for testing)
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linux
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
105struct dwc3_data {
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
116static 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
132static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
133{
134 return readl((data->usbss) + offset);
135}
136
137static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
138{
139 writel(value, (data->usbss) + offset);
140}
141
142static int phy_syscon_pll_refclk(struct dwc3_data *data)
143{
144 struct device *dev = data->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 data->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 data->offset = args.args[0];
164
165 ret = regmap_update_bits(data->syscon, data->offset, PHY_PLL_REFCLK_MASK, data->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
174static 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_data *data;
179 int i, ret;
180 unsigned long rate;
181 u32 reg;
182
183 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
184 if (!data)
185 return -ENOMEM;
186
187 data->dev = dev;
188 platform_set_drvdata(pdev, data);
189
190 data->usbss = devm_platform_ioremap_resource(pdev, 0);
191 if (IS_ERR(data->usbss)) {
192 dev_err(dev, "can't map IOMEM resource\n");
193 return PTR_ERR(data->usbss);
194 }
195
196 data->usb2_refclk = devm_clk_get(dev, "ref");
197 if (IS_ERR(data->usb2_refclk)) {
198 dev_err(dev, "can't get usb2_refclk\n");
199 return PTR_ERR(data->usb2_refclk);
200 }
201
202 /* Calculate the rate code */
203 rate = clk_get_rate(data->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 data->rate_code = i;
216
217 /* Read the syscon property and set the rate code */
218 ret = phy_syscon_pll_refclk(data);
219 if (ret)
220 return ret;
221
222 /* VBUS divider select */
223 data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
224 reg = dwc3_ti_readl(data, USBSS_PHY_CONFIG);
225 if (data->vbus_divider)
226 reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
227
228 dwc3_ti_writel(data, 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(data->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(data, USBSS_MODE_CONTROL);
247 reg |= USBSS_MODE_VALID;
248 dwc3_ti_writel(data, 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
263err_pm_disable:
264 clk_disable_unprepare(data->usb2_refclk);
265 pm_runtime_disable(dev);
266 pm_runtime_set_suspended(dev);
267 return ret;
268}
269
270static int dwc3_ti_remove_core(struct device *dev, void *c)
271{
272 struct platform_device *pdev = to_platform_device(dev);
273
274 platform_device_unregister(pdev);
275 return 0;
276}
277
278static int dwc3_ti_remove(struct platform_device *pdev)
279{
280 struct device *dev = &pdev->dev;
281 struct dwc3_data *data = platform_get_drvdata(pdev);
282 u32 reg;
283
284 device_for_each_child(dev, NULL, dwc3_ti_remove_core);
285
286 /* Clear mode valid bit */
287 reg = dwc3_ti_readl(data, USBSS_MODE_CONTROL);
288 reg &= ~USBSS_MODE_VALID;
289 dwc3_ti_writel(data, USBSS_MODE_CONTROL, reg);
290
291 pm_runtime_put_sync(dev);
292 clk_disable_unprepare(data->usb2_refclk);
293 pm_runtime_disable(dev);
294 pm_runtime_set_suspended(dev);
295
296 platform_set_drvdata(pdev, NULL);
297 return 0;
298}
299
300#ifdef CONFIG_PM
301static int dwc3_ti_suspend_common(struct device *dev)
302{
303 struct dwc3_data *data = dev_get_drvdata(dev);
304 u32 reg, current_prtcap_dir;
305
306 if (device_may_wakeup(dev)) {
307 reg = dwc3_ti_readl(data, USBSS_CORE_STAT);
308 current_prtcap_dir = (reg & USBSS_CORE_OPERATIONAL_MODE_MASK)
309 >> USBSS_CORE_OPERATIONAL_MODE_SHIFT;
310 /* Set wakeup config enable bits */
311 reg = dwc3_ti_readl(data, USBSS_WAKEUP_CONFIG);
312 if (current_prtcap_dir == DWC3_GCTL_PRTCAP_HOST) {
313 reg = USBSS_WAKEUP_CFG_LINESTATE_EN | USBSS_WAKEUP_CFG_OVERCURRENT_EN;
314 } else {
315 reg = USBSS_WAKEUP_CFG_VBUSVALID_EN | USBSS_WAKEUP_CFG_SESSVALID_EN;
316 /*
317 * Enable LINESTATE wake up only if connected to bus
318 * and in U2/L3 state else it causes spurious wake-up.
319 */
320 }
321 dwc3_ti_writel(data, USBSS_WAKEUP_CONFIG, reg);
322 /* clear wakeup status so we know what caused the wake up */
323 dwc3_ti_writel(data, USBSS_WAKEUP_STAT, USBSS_WAKEUP_STAT_CLR);
324 }
325
326 clk_disable_unprepare(data->usb2_refclk);
327
328 return 0;
329}
330
331static int dwc3_ti_resume_common(struct device *dev)
332{
333 struct dwc3_data *data = dev_get_drvdata(dev);
334 u32 reg;
335
336 clk_prepare_enable(data->usb2_refclk);
337
338 if (device_may_wakeup(dev)) {
339 /* Clear wakeup config enable bits */
340 dwc3_ti_writel(data, USBSS_WAKEUP_CONFIG, USBSS_WAKEUP_CFG_NONE);
341 }
342
343 reg = dwc3_ti_readl(data, USBSS_WAKEUP_STAT);
344 data->wakeup_stat = reg;
345
346 return 0;
347}
348
349static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
350 dwc3_ti_resume_common, NULL);
351
352#define DEV_PM_OPS (&dwc3_ti_pm_ops)
353#else
354#define DEV_PM_OPS NULL
355#endif /* CONFIG_PM */
356
357static const struct of_device_id dwc3_ti_of_match[] = {
358 { .compatible = "ti,am62-usb"},
359 {},
360};
361MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
362
363static struct platform_driver dwc3_ti_driver = {
364 .probe = dwc3_ti_probe,
365 .remove = dwc3_ti_remove,
366 .driver = {
367 .name = "dwc3-am62",
368 .pm = DEV_PM_OPS,
369 .of_match_table = dwc3_ti_of_match,
370 },
371};
372
373module_platform_driver(dwc3_ti_driver);
374
375MODULE_ALIAS("platform:dwc3-am62");
376MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
377MODULE_LICENSE("GPL");
378MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");