xref: /linux/drivers/usb/dwc3/dwc3-am62.c (revision 5e3992fe72748ed3892be876f09d4d990548b7af)
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_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 
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 
132 static inline u32 dwc3_ti_readl(struct dwc3_data *data, u32 offset)
133 {
134 	return readl((data->usbss) + offset);
135 }
136 
137 static inline void dwc3_ti_writel(struct dwc3_data *data, u32 offset, u32 value)
138 {
139 	writel(value, (data->usbss) + offset);
140 }
141 
142 static 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 
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_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 
263 err_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 
270 static 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 
278 static 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
301 static 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 
331 static 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 
349 static 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 
357 static const struct of_device_id dwc3_ti_of_match[] = {
358 	{ .compatible = "ti,am62-usb"},
359 	{},
360 };
361 MODULE_DEVICE_TABLE(of, dwc3_ti_of_match);
362 
363 static 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 
373 module_platform_driver(dwc3_ti_driver);
374 
375 MODULE_ALIAS("platform:dwc3-am62");
376 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>");
377 MODULE_LICENSE("GPL");
378 MODULE_DESCRIPTION("DesignWare USB3 TI Glue Layer");
379