xref: /linux/drivers/usb/dwc3/dwc3-am62.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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 
138 static inline u32 dwc3_ti_readl(struct dwc3_am62 *am62, u32 offset)
139 {
140 	return readl((am62->usbss) + offset);
141 }
142 
143 static inline void dwc3_ti_writel(struct dwc3_am62 *am62, u32 offset, u32 value)
144 {
145 	writel(value, (am62->usbss) + offset);
146 }
147 
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 
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 
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
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 
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