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 /* USB_PHY_CTRL register bits in CTRL_MMR */
101 #define PHY_CORE_VOLTAGE_MASK BIT(31)
102 #define PHY_PLL_REFCLK_MASK GENMASK(3, 0)
103
104 /* USB PHY2 register offsets */
105 #define USB_PHY_PLL_REG12 0x130
106 #define USB_PHY_PLL_LDO_REF_EN BIT(5)
107 #define USB_PHY_PLL_LDO_REF_EN_EN BIT(4)
108
109 #define DWC3_AM62_AUTOSUSPEND_DELAY 100
110
111 struct dwc3_am62 {
112 struct device *dev;
113 void __iomem *usbss;
114 struct clk *usb2_refclk;
115 int rate_code;
116 struct regmap *syscon;
117 unsigned int offset;
118 unsigned int vbus_divider;
119 u32 wakeup_stat;
120 };
121
122 static const int dwc3_ti_rate_table[] = { /* in KHZ */
123 9600,
124 10000,
125 12000,
126 19200,
127 20000,
128 24000,
129 25000,
130 26000,
131 38400,
132 40000,
133 58000,
134 50000,
135 52000,
136 };
137
dwc3_ti_readl(struct dwc3_am62 * am62,u32 offset)138 static inline u32 dwc3_ti_readl(struct dwc3_am62 *am62, u32 offset)
139 {
140 return readl((am62->usbss) + offset);
141 }
142
dwc3_ti_writel(struct dwc3_am62 * am62,u32 offset,u32 value)143 static inline void dwc3_ti_writel(struct dwc3_am62 *am62, u32 offset, u32 value)
144 {
145 writel(value, (am62->usbss) + offset);
146 }
147
phy_syscon_pll_refclk(struct dwc3_am62 * am62)148 static int phy_syscon_pll_refclk(struct dwc3_am62 *am62)
149 {
150 struct device *dev = am62->dev;
151 struct device_node *node = dev->of_node;
152 struct of_phandle_args args;
153 struct regmap *syscon;
154 int ret;
155
156 syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-phy-pll-refclk");
157 if (IS_ERR(syscon)) {
158 dev_err(dev, "unable to get ti,syscon-phy-pll-refclk regmap\n");
159 return PTR_ERR(syscon);
160 }
161
162 am62->syscon = syscon;
163
164 ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-phy-pll-refclk", 1,
165 0, &args);
166 if (ret)
167 return ret;
168
169 am62->offset = args.args[0];
170
171 /* Core voltage. PHY_CORE_VOLTAGE bit Recommended to be 0 always */
172 ret = regmap_update_bits(am62->syscon, am62->offset, PHY_CORE_VOLTAGE_MASK, 0);
173 if (ret) {
174 dev_err(dev, "failed to set phy core voltage\n");
175 return ret;
176 }
177
178 ret = regmap_update_bits(am62->syscon, am62->offset, PHY_PLL_REFCLK_MASK, am62->rate_code);
179 if (ret) {
180 dev_err(dev, "failed to set phy pll reference clock rate\n");
181 return ret;
182 }
183
184 return 0;
185 }
186
dwc3_ti_probe(struct platform_device * pdev)187 static int dwc3_ti_probe(struct platform_device *pdev)
188 {
189 struct device *dev = &pdev->dev;
190 struct device_node *node = pdev->dev.of_node;
191 struct dwc3_am62 *am62;
192 unsigned long rate;
193 void __iomem *phy;
194 int i, ret;
195 u32 reg;
196
197 am62 = devm_kzalloc(dev, sizeof(*am62), GFP_KERNEL);
198 if (!am62)
199 return -ENOMEM;
200
201 am62->dev = dev;
202 platform_set_drvdata(pdev, am62);
203
204 am62->usbss = devm_platform_ioremap_resource(pdev, 0);
205 if (IS_ERR(am62->usbss)) {
206 dev_err(dev, "can't map IOMEM resource\n");
207 return PTR_ERR(am62->usbss);
208 }
209
210 am62->usb2_refclk = devm_clk_get(dev, "ref");
211 if (IS_ERR(am62->usb2_refclk)) {
212 dev_err(dev, "can't get usb2_refclk\n");
213 return PTR_ERR(am62->usb2_refclk);
214 }
215
216 /* Calculate the rate code */
217 rate = clk_get_rate(am62->usb2_refclk);
218 rate /= 1000; // To KHz
219 for (i = 0; i < ARRAY_SIZE(dwc3_ti_rate_table); i++) {
220 if (dwc3_ti_rate_table[i] == rate)
221 break;
222 }
223
224 if (i == ARRAY_SIZE(dwc3_ti_rate_table)) {
225 dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
226 return -EINVAL;
227 }
228
229 am62->rate_code = i;
230
231 /* Read the syscon property and set the rate code */
232 ret = phy_syscon_pll_refclk(am62);
233 if (ret)
234 return ret;
235
236 /* Workaround Errata i2409 */
237 phy = devm_platform_ioremap_resource(pdev, 1);
238 if (IS_ERR(phy)) {
239 dev_err(dev, "can't map PHY IOMEM resource. Won't apply i2409 fix.\n");
240 phy = NULL;
241 } else {
242 reg = readl(phy + USB_PHY_PLL_REG12);
243 reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN;
244 writel(reg, phy + USB_PHY_PLL_REG12);
245 }
246
247 /* VBUS divider select */
248 am62->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
249 reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG);
250 if (am62->vbus_divider)
251 reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT;
252
253 dwc3_ti_writel(am62, USBSS_PHY_CONFIG, reg);
254
255 pm_runtime_set_active(dev);
256 pm_runtime_enable(dev);
257 /*
258 * Don't ignore its dependencies with its children
259 */
260 pm_suspend_ignore_children(dev, false);
261 clk_prepare_enable(am62->usb2_refclk);
262 pm_runtime_get_noresume(dev);
263
264 ret = of_platform_populate(node, NULL, NULL, dev);
265 if (ret) {
266 dev_err(dev, "failed to create dwc3 core: %d\n", ret);
267 goto err_pm_disable;
268 }
269
270 /* Set mode valid bit to indicate role is valid */
271 reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL);
272 reg |= USBSS_MODE_VALID;
273 dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg);
274
275 /* Device has capability to wakeup system from sleep */
276 device_set_wakeup_capable(dev, true);
277 ret = device_wakeup_enable(dev);
278 if (ret)
279 dev_err(dev, "couldn't enable device as a wakeup source: %d\n", ret);
280
281 /* Setting up autosuspend */
282 pm_runtime_set_autosuspend_delay(dev, DWC3_AM62_AUTOSUSPEND_DELAY);
283 pm_runtime_use_autosuspend(dev);
284 pm_runtime_mark_last_busy(dev);
285 pm_runtime_put_autosuspend(dev);
286 return 0;
287
288 err_pm_disable:
289 clk_disable_unprepare(am62->usb2_refclk);
290 pm_runtime_disable(dev);
291 pm_runtime_set_suspended(dev);
292 return ret;
293 }
294
dwc3_ti_remove(struct platform_device * pdev)295 static void dwc3_ti_remove(struct platform_device *pdev)
296 {
297 struct device *dev = &pdev->dev;
298 struct dwc3_am62 *am62 = platform_get_drvdata(pdev);
299 u32 reg;
300
301 pm_runtime_get_sync(dev);
302 device_init_wakeup(dev, false);
303 of_platform_depopulate(dev);
304
305 /* Clear mode valid bit */
306 reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL);
307 reg &= ~USBSS_MODE_VALID;
308 dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg);
309
310 pm_runtime_put_sync(dev);
311 pm_runtime_disable(dev);
312 pm_runtime_set_suspended(dev);
313 }
314
315 #ifdef CONFIG_PM
dwc3_ti_suspend_common(struct device * dev)316 static int dwc3_ti_suspend_common(struct device *dev)
317 {
318 struct dwc3_am62 *am62 = dev_get_drvdata(dev);
319 u32 reg, current_prtcap_dir;
320
321 if (device_may_wakeup(dev)) {
322 reg = dwc3_ti_readl(am62, USBSS_CORE_STAT);
323 current_prtcap_dir = (reg & USBSS_CORE_OPERATIONAL_MODE_MASK)
324 >> USBSS_CORE_OPERATIONAL_MODE_SHIFT;
325 /* Set wakeup config enable bits */
326 reg = dwc3_ti_readl(am62, USBSS_WAKEUP_CONFIG);
327 if (current_prtcap_dir == DWC3_GCTL_PRTCAP_HOST) {
328 reg = USBSS_WAKEUP_CFG_LINESTATE_EN | USBSS_WAKEUP_CFG_OVERCURRENT_EN;
329 } else {
330 reg = USBSS_WAKEUP_CFG_VBUSVALID_EN | USBSS_WAKEUP_CFG_SESSVALID_EN;
331 /*
332 * Enable LINESTATE wake up only if connected to bus
333 * and in U2/L3 state else it causes spurious wake-up.
334 */
335 }
336 dwc3_ti_writel(am62, USBSS_WAKEUP_CONFIG, reg);
337 /* clear wakeup status so we know what caused the wake up */
338 dwc3_ti_writel(am62, USBSS_WAKEUP_STAT, USBSS_WAKEUP_STAT_CLR);
339 }
340
341 clk_disable_unprepare(am62->usb2_refclk);
342
343 return 0;
344 }
345
dwc3_ti_resume_common(struct device * dev)346 static int dwc3_ti_resume_common(struct device *dev)
347 {
348 struct dwc3_am62 *am62 = dev_get_drvdata(dev);
349 u32 reg;
350
351 clk_prepare_enable(am62->usb2_refclk);
352
353 if (device_may_wakeup(dev)) {
354 /* Clear wakeup config enable bits */
355 dwc3_ti_writel(am62, USBSS_WAKEUP_CONFIG, USBSS_WAKEUP_CFG_NONE);
356 }
357
358 reg = dwc3_ti_readl(am62, USBSS_WAKEUP_STAT);
359 am62->wakeup_stat = reg;
360
361 return 0;
362 }
363
364 static UNIVERSAL_DEV_PM_OPS(dwc3_ti_pm_ops, dwc3_ti_suspend_common,
365 dwc3_ti_resume_common, NULL);
366
367 #define DEV_PM_OPS (&dwc3_ti_pm_ops)
368 #else
369 #define DEV_PM_OPS NULL
370 #endif /* CONFIG_PM */
371
372 static const struct of_device_id dwc3_ti_of_match[] = {
373 { .compatible = "ti,am62-usb"},
374 {},
375 };
376 MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
377
378 static struct platform_driver dwc3_ti_driver = {
379 .probe = dwc3_ti_probe,
380 .remove_new = dwc3_ti_remove,
381 .driver = {
382 .name = "dwc3-am62",
383 .pm = DEV_PM_OPS,
384 .of_match_table = dwc3_ti_of_match,
385 },
386 };
387
388 module_platform_driver(dwc3_ti_driver);
389
390 MODULE_ALIAS("platform:dwc3-am62");
391 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
392 MODULE_LICENSE("GPL");
393 MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");
394