1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Rockchip usb PHY driver
4  *
5  * Copyright (C) 2014 Yunzhi Li <lyz@rock-chips.com>
6  * Copyright (C) 2014 ROCKCHIP, Inc.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/clk-provider.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/mutex.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_platform.h>
18 #include <linux/phy/phy.h>
19 #include <linux/platform_device.h>
20 #include <linux/regulator/consumer.h>
21 #include <linux/reset.h>
22 #include <linux/regmap.h>
23 #include <linux/mfd/syscon.h>
24 #include <linux/delay.h>
25 
26 static int enable_usb_uart;
27 
28 #define HIWORD_UPDATE(val, mask) \
29 		((val) | (mask) << 16)
30 
31 #define UOC_CON0					0x00
32 #define UOC_CON0_SIDDQ					BIT(13)
33 #define UOC_CON0_DISABLE				BIT(4)
34 #define UOC_CON0_COMMON_ON_N				BIT(0)
35 
36 #define UOC_CON2					0x08
37 #define UOC_CON2_SOFT_CON_SEL				BIT(2)
38 
39 #define UOC_CON3					0x0c
40 /* bits present on rk3188 and rk3288 phys */
41 #define UOC_CON3_UTMI_TERMSEL_FULLSPEED			BIT(5)
42 #define UOC_CON3_UTMI_XCVRSEELCT_FSTRANSC		(1 << 3)
43 #define UOC_CON3_UTMI_XCVRSEELCT_MASK			(3 << 3)
44 #define UOC_CON3_UTMI_OPMODE_NODRIVING			(1 << 1)
45 #define UOC_CON3_UTMI_OPMODE_MASK			(3 << 1)
46 #define UOC_CON3_UTMI_SUSPENDN				BIT(0)
47 
48 struct rockchip_usb_phys {
49 	int reg;
50 	const char *pll_name;
51 };
52 
53 struct rockchip_usb_phy_base;
54 struct rockchip_usb_phy_pdata {
55 	struct rockchip_usb_phys *phys;
56 	int (*init_usb_uart)(struct regmap *grf,
57 			     const struct rockchip_usb_phy_pdata *pdata);
58 	int usb_uart_phy;
59 };
60 
61 struct rockchip_usb_phy_base {
62 	struct device *dev;
63 	struct regmap *reg_base;
64 	const struct rockchip_usb_phy_pdata *pdata;
65 };
66 
67 struct rockchip_usb_phy {
68 	struct rockchip_usb_phy_base *base;
69 	struct device_node *np;
70 	unsigned int	reg_offset;
71 	struct clk	*clk;
72 	struct clk      *clk480m;
73 	struct clk_hw	clk480m_hw;
74 	struct phy	*phy;
75 	bool		uart_enabled;
76 	struct reset_control *reset;
77 	struct regulator *vbus;
78 };
79 
80 static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
81 					   bool siddq)
82 {
83 	u32 val = HIWORD_UPDATE(siddq ? UOC_CON0_SIDDQ : 0, UOC_CON0_SIDDQ);
84 
85 	return regmap_write(phy->base->reg_base, phy->reg_offset, val);
86 }
87 
88 static unsigned long rockchip_usb_phy480m_recalc_rate(struct clk_hw *hw,
89 						unsigned long parent_rate)
90 {
91 	return 480000000;
92 }
93 
94 static void rockchip_usb_phy480m_disable(struct clk_hw *hw)
95 {
96 	struct rockchip_usb_phy *phy = container_of(hw,
97 						    struct rockchip_usb_phy,
98 						    clk480m_hw);
99 
100 	if (phy->vbus)
101 		regulator_disable(phy->vbus);
102 
103 	/* Power down usb phy analog blocks by set siddq 1 */
104 	rockchip_usb_phy_power(phy, 1);
105 }
106 
107 static int rockchip_usb_phy480m_enable(struct clk_hw *hw)
108 {
109 	struct rockchip_usb_phy *phy = container_of(hw,
110 						    struct rockchip_usb_phy,
111 						    clk480m_hw);
112 
113 	/* Power up usb phy analog blocks by set siddq 0 */
114 	return rockchip_usb_phy_power(phy, 0);
115 }
116 
117 static int rockchip_usb_phy480m_is_enabled(struct clk_hw *hw)
118 {
119 	struct rockchip_usb_phy *phy = container_of(hw,
120 						    struct rockchip_usb_phy,
121 						    clk480m_hw);
122 	int ret;
123 	u32 val;
124 
125 	ret = regmap_read(phy->base->reg_base, phy->reg_offset, &val);
126 	if (ret < 0)
127 		return ret;
128 
129 	return (val & UOC_CON0_SIDDQ) ? 0 : 1;
130 }
131 
132 static const struct clk_ops rockchip_usb_phy480m_ops = {
133 	.enable = rockchip_usb_phy480m_enable,
134 	.disable = rockchip_usb_phy480m_disable,
135 	.is_enabled = rockchip_usb_phy480m_is_enabled,
136 	.recalc_rate = rockchip_usb_phy480m_recalc_rate,
137 };
138 
139 static int rockchip_usb_phy_power_off(struct phy *_phy)
140 {
141 	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
142 
143 	if (phy->uart_enabled)
144 		return -EBUSY;
145 
146 	clk_disable_unprepare(phy->clk480m);
147 
148 	return 0;
149 }
150 
151 static int rockchip_usb_phy_power_on(struct phy *_phy)
152 {
153 	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
154 
155 	if (phy->uart_enabled)
156 		return -EBUSY;
157 
158 	if (phy->vbus) {
159 		int ret;
160 
161 		ret = regulator_enable(phy->vbus);
162 		if (ret)
163 			return ret;
164 	}
165 
166 	return clk_prepare_enable(phy->clk480m);
167 }
168 
169 static int rockchip_usb_phy_reset(struct phy *_phy)
170 {
171 	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
172 
173 	if (phy->reset) {
174 		reset_control_assert(phy->reset);
175 		udelay(10);
176 		reset_control_deassert(phy->reset);
177 	}
178 
179 	return 0;
180 }
181 
182 static const struct phy_ops ops = {
183 	.power_on	= rockchip_usb_phy_power_on,
184 	.power_off	= rockchip_usb_phy_power_off,
185 	.reset		= rockchip_usb_phy_reset,
186 	.owner		= THIS_MODULE,
187 };
188 
189 static void rockchip_usb_phy_action(void *data)
190 {
191 	struct rockchip_usb_phy *rk_phy = data;
192 
193 	if (!rk_phy->uart_enabled) {
194 		of_clk_del_provider(rk_phy->np);
195 		clk_unregister(rk_phy->clk480m);
196 	}
197 
198 	if (rk_phy->clk)
199 		clk_put(rk_phy->clk);
200 }
201 
202 static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
203 				 struct device_node *child)
204 {
205 	struct rockchip_usb_phy *rk_phy;
206 	unsigned int reg_offset;
207 	const char *clk_name;
208 	struct clk_init_data init;
209 	int err, i;
210 
211 	rk_phy = devm_kzalloc(base->dev, sizeof(*rk_phy), GFP_KERNEL);
212 	if (!rk_phy)
213 		return -ENOMEM;
214 
215 	rk_phy->base = base;
216 	rk_phy->np = child;
217 
218 	if (of_property_read_u32(child, "reg", &reg_offset)) {
219 		dev_err(base->dev, "missing reg property in node %pOFn\n",
220 			child);
221 		return -EINVAL;
222 	}
223 
224 	rk_phy->reset = of_reset_control_get(child, "phy-reset");
225 	if (IS_ERR(rk_phy->reset))
226 		rk_phy->reset = NULL;
227 
228 	rk_phy->reg_offset = reg_offset;
229 
230 	rk_phy->clk = of_clk_get_by_name(child, "phyclk");
231 	if (IS_ERR(rk_phy->clk))
232 		rk_phy->clk = NULL;
233 
234 	i = 0;
235 	init.name = NULL;
236 	while (base->pdata->phys[i].reg) {
237 		if (base->pdata->phys[i].reg == reg_offset) {
238 			init.name = base->pdata->phys[i].pll_name;
239 			break;
240 		}
241 		i++;
242 	}
243 
244 	if (!init.name) {
245 		dev_err(base->dev, "phy data not found\n");
246 		return -EINVAL;
247 	}
248 
249 	if (enable_usb_uart && base->pdata->usb_uart_phy == i) {
250 		dev_dbg(base->dev, "phy%d used as uart output\n", i);
251 		rk_phy->uart_enabled = true;
252 	} else {
253 		if (rk_phy->clk) {
254 			clk_name = __clk_get_name(rk_phy->clk);
255 			init.flags = 0;
256 			init.parent_names = &clk_name;
257 			init.num_parents = 1;
258 		} else {
259 			init.flags = 0;
260 			init.parent_names = NULL;
261 			init.num_parents = 0;
262 		}
263 
264 		init.ops = &rockchip_usb_phy480m_ops;
265 		rk_phy->clk480m_hw.init = &init;
266 
267 		rk_phy->clk480m = clk_register(base->dev, &rk_phy->clk480m_hw);
268 		if (IS_ERR(rk_phy->clk480m)) {
269 			err = PTR_ERR(rk_phy->clk480m);
270 			goto err_clk;
271 		}
272 
273 		err = of_clk_add_provider(child, of_clk_src_simple_get,
274 					rk_phy->clk480m);
275 		if (err < 0)
276 			goto err_clk_prov;
277 	}
278 
279 	err = devm_add_action_or_reset(base->dev, rockchip_usb_phy_action,
280 				       rk_phy);
281 	if (err)
282 		return err;
283 
284 	rk_phy->phy = devm_phy_create(base->dev, child, &ops);
285 	if (IS_ERR(rk_phy->phy)) {
286 		dev_err(base->dev, "failed to create PHY\n");
287 		return PTR_ERR(rk_phy->phy);
288 	}
289 	phy_set_drvdata(rk_phy->phy, rk_phy);
290 
291 	rk_phy->vbus = devm_regulator_get_optional(&rk_phy->phy->dev, "vbus");
292 	if (IS_ERR(rk_phy->vbus)) {
293 		if (PTR_ERR(rk_phy->vbus) == -EPROBE_DEFER)
294 			return PTR_ERR(rk_phy->vbus);
295 		rk_phy->vbus = NULL;
296 	}
297 
298 	/*
299 	 * When acting as uart-pipe, just keep clock on otherwise
300 	 * only power up usb phy when it use, so disable it when init
301 	 */
302 	if (rk_phy->uart_enabled)
303 		return clk_prepare_enable(rk_phy->clk);
304 	else
305 		return rockchip_usb_phy_power(rk_phy, 1);
306 
307 err_clk_prov:
308 	if (!rk_phy->uart_enabled)
309 		clk_unregister(rk_phy->clk480m);
310 err_clk:
311 	if (rk_phy->clk)
312 		clk_put(rk_phy->clk);
313 	return err;
314 }
315 
316 static const struct rockchip_usb_phy_pdata rk3066a_pdata = {
317 	.phys = (struct rockchip_usb_phys[]){
318 		{ .reg = 0x17c, .pll_name = "sclk_otgphy0_480m" },
319 		{ .reg = 0x188, .pll_name = "sclk_otgphy1_480m" },
320 		{ /* sentinel */ }
321 	},
322 };
323 
324 static int __init rockchip_init_usb_uart_common(struct regmap *grf,
325 				const struct rockchip_usb_phy_pdata *pdata)
326 {
327 	int regoffs = pdata->phys[pdata->usb_uart_phy].reg;
328 	int ret;
329 	u32 val;
330 
331 	/*
332 	 * COMMON_ON and DISABLE settings are described in the TRM,
333 	 * but were not present in the original code.
334 	 * Also disable the analog phy components to save power.
335 	 */
336 	val = HIWORD_UPDATE(UOC_CON0_COMMON_ON_N
337 				| UOC_CON0_DISABLE
338 				| UOC_CON0_SIDDQ,
339 			    UOC_CON0_COMMON_ON_N
340 				| UOC_CON0_DISABLE
341 				| UOC_CON0_SIDDQ);
342 	ret = regmap_write(grf, regoffs + UOC_CON0, val);
343 	if (ret)
344 		return ret;
345 
346 	val = HIWORD_UPDATE(UOC_CON2_SOFT_CON_SEL,
347 			    UOC_CON2_SOFT_CON_SEL);
348 	ret = regmap_write(grf, regoffs + UOC_CON2, val);
349 	if (ret)
350 		return ret;
351 
352 	val = HIWORD_UPDATE(UOC_CON3_UTMI_OPMODE_NODRIVING
353 				| UOC_CON3_UTMI_XCVRSEELCT_FSTRANSC
354 				| UOC_CON3_UTMI_TERMSEL_FULLSPEED,
355 			    UOC_CON3_UTMI_SUSPENDN
356 				| UOC_CON3_UTMI_OPMODE_MASK
357 				| UOC_CON3_UTMI_XCVRSEELCT_MASK
358 				| UOC_CON3_UTMI_TERMSEL_FULLSPEED);
359 	ret = regmap_write(grf, UOC_CON3, val);
360 	if (ret)
361 		return ret;
362 
363 	return 0;
364 }
365 
366 #define RK3188_UOC0_CON0				0x10c
367 #define RK3188_UOC0_CON0_BYPASSSEL			BIT(9)
368 #define RK3188_UOC0_CON0_BYPASSDMEN			BIT(8)
369 
370 /*
371  * Enable the bypass of uart2 data through the otg usb phy.
372  * See description of rk3288-variant for details.
373  */
374 static int __init rk3188_init_usb_uart(struct regmap *grf,
375 				const struct rockchip_usb_phy_pdata *pdata)
376 {
377 	u32 val;
378 	int ret;
379 
380 	ret = rockchip_init_usb_uart_common(grf, pdata);
381 	if (ret)
382 		return ret;
383 
384 	val = HIWORD_UPDATE(RK3188_UOC0_CON0_BYPASSSEL
385 				| RK3188_UOC0_CON0_BYPASSDMEN,
386 			    RK3188_UOC0_CON0_BYPASSSEL
387 				| RK3188_UOC0_CON0_BYPASSDMEN);
388 	ret = regmap_write(grf, RK3188_UOC0_CON0, val);
389 	if (ret)
390 		return ret;
391 
392 	return 0;
393 }
394 
395 static const struct rockchip_usb_phy_pdata rk3188_pdata = {
396 	.phys = (struct rockchip_usb_phys[]){
397 		{ .reg = 0x10c, .pll_name = "sclk_otgphy0_480m" },
398 		{ .reg = 0x11c, .pll_name = "sclk_otgphy1_480m" },
399 		{ /* sentinel */ }
400 	},
401 	.init_usb_uart = rk3188_init_usb_uart,
402 	.usb_uart_phy = 0,
403 };
404 
405 #define RK3288_UOC0_CON3				0x32c
406 #define RK3288_UOC0_CON3_BYPASSDMEN			BIT(6)
407 #define RK3288_UOC0_CON3_BYPASSSEL			BIT(7)
408 
409 /*
410  * Enable the bypass of uart2 data through the otg usb phy.
411  * Original description in the TRM.
412  * 1. Disable the OTG block by setting OTGDISABLE0 to 1’b1.
413  * 2. Disable the pull-up resistance on the D+ line by setting
414  *    OPMODE0[1:0] to 2’b01.
415  * 3. To ensure that the XO, Bias, and PLL blocks are powered down in Suspend
416  *    mode, set COMMONONN to 1’b1.
417  * 4. Place the USB PHY in Suspend mode by setting SUSPENDM0 to 1’b0.
418  * 5. Set BYPASSSEL0 to 1’b1.
419  * 6. To transmit data, controls BYPASSDMEN0, and BYPASSDMDATA0.
420  * To receive data, monitor FSVPLUS0.
421  *
422  * The actual code in the vendor kernel does some things differently.
423  */
424 static int __init rk3288_init_usb_uart(struct regmap *grf,
425 				const struct rockchip_usb_phy_pdata *pdata)
426 {
427 	u32 val;
428 	int ret;
429 
430 	ret = rockchip_init_usb_uart_common(grf, pdata);
431 	if (ret)
432 		return ret;
433 
434 	val = HIWORD_UPDATE(RK3288_UOC0_CON3_BYPASSSEL
435 				| RK3288_UOC0_CON3_BYPASSDMEN,
436 			    RK3288_UOC0_CON3_BYPASSSEL
437 				| RK3288_UOC0_CON3_BYPASSDMEN);
438 	ret = regmap_write(grf, RK3288_UOC0_CON3, val);
439 	if (ret)
440 		return ret;
441 
442 	return 0;
443 }
444 
445 static const struct rockchip_usb_phy_pdata rk3288_pdata = {
446 	.phys = (struct rockchip_usb_phys[]){
447 		{ .reg = 0x320, .pll_name = "sclk_otgphy0_480m" },
448 		{ .reg = 0x334, .pll_name = "sclk_otgphy1_480m" },
449 		{ .reg = 0x348, .pll_name = "sclk_otgphy2_480m" },
450 		{ /* sentinel */ }
451 	},
452 	.init_usb_uart = rk3288_init_usb_uart,
453 	.usb_uart_phy = 0,
454 };
455 
456 static int rockchip_usb_phy_probe(struct platform_device *pdev)
457 {
458 	struct device *dev = &pdev->dev;
459 	struct rockchip_usb_phy_base *phy_base;
460 	struct phy_provider *phy_provider;
461 	const struct of_device_id *match;
462 	struct device_node *child;
463 	int err;
464 
465 	phy_base = devm_kzalloc(dev, sizeof(*phy_base), GFP_KERNEL);
466 	if (!phy_base)
467 		return -ENOMEM;
468 
469 	match = of_match_device(dev->driver->of_match_table, dev);
470 	if (!match || !match->data) {
471 		dev_err(dev, "missing phy data\n");
472 		return -EINVAL;
473 	}
474 
475 	phy_base->pdata = match->data;
476 
477 	phy_base->dev = dev;
478 	phy_base->reg_base = ERR_PTR(-ENODEV);
479 	if (dev->parent && dev->parent->of_node)
480 		phy_base->reg_base = syscon_node_to_regmap(
481 						dev->parent->of_node);
482 	if (IS_ERR(phy_base->reg_base))
483 		phy_base->reg_base = syscon_regmap_lookup_by_phandle(
484 						dev->of_node, "rockchip,grf");
485 	if (IS_ERR(phy_base->reg_base)) {
486 		dev_err(&pdev->dev, "Missing rockchip,grf property\n");
487 		return PTR_ERR(phy_base->reg_base);
488 	}
489 
490 	for_each_available_child_of_node(dev->of_node, child) {
491 		err = rockchip_usb_phy_init(phy_base, child);
492 		if (err) {
493 			of_node_put(child);
494 			return err;
495 		}
496 	}
497 
498 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
499 	return PTR_ERR_OR_ZERO(phy_provider);
500 }
501 
502 static const struct of_device_id rockchip_usb_phy_dt_ids[] = {
503 	{ .compatible = "rockchip,rk3066a-usb-phy", .data = &rk3066a_pdata },
504 	{ .compatible = "rockchip,rk3188-usb-phy", .data = &rk3188_pdata },
505 	{ .compatible = "rockchip,rk3288-usb-phy", .data = &rk3288_pdata },
506 	{}
507 };
508 
509 MODULE_DEVICE_TABLE(of, rockchip_usb_phy_dt_ids);
510 
511 static struct platform_driver rockchip_usb_driver = {
512 	.probe		= rockchip_usb_phy_probe,
513 	.driver		= {
514 		.name	= "rockchip-usb-phy",
515 		.of_match_table = rockchip_usb_phy_dt_ids,
516 	},
517 };
518 
519 module_platform_driver(rockchip_usb_driver);
520 
521 #ifndef MODULE
522 static int __init rockchip_init_usb_uart(void)
523 {
524 	const struct of_device_id *match;
525 	const struct rockchip_usb_phy_pdata *data;
526 	struct device_node *np;
527 	struct regmap *grf;
528 	int ret;
529 
530 	if (!enable_usb_uart)
531 		return 0;
532 
533 	np = of_find_matching_node_and_match(NULL, rockchip_usb_phy_dt_ids,
534 					     &match);
535 	if (!np) {
536 		pr_err("%s: failed to find usbphy node\n", __func__);
537 		return -ENOTSUPP;
538 	}
539 
540 	pr_debug("%s: using settings for %s\n", __func__, match->compatible);
541 	data = match->data;
542 
543 	if (!data->init_usb_uart) {
544 		pr_err("%s: usb-uart not available on %s\n",
545 		       __func__, match->compatible);
546 		return -ENOTSUPP;
547 	}
548 
549 	grf = ERR_PTR(-ENODEV);
550 	if (np->parent)
551 		grf = syscon_node_to_regmap(np->parent);
552 	if (IS_ERR(grf))
553 		grf = syscon_regmap_lookup_by_phandle(np, "rockchip,grf");
554 	if (IS_ERR(grf)) {
555 		pr_err("%s: Missing rockchip,grf property, %lu\n",
556 		       __func__, PTR_ERR(grf));
557 		return PTR_ERR(grf);
558 	}
559 
560 	ret = data->init_usb_uart(grf, data);
561 	if (ret) {
562 		pr_err("%s: could not init usb_uart, %d\n", __func__, ret);
563 		enable_usb_uart = 0;
564 		return ret;
565 	}
566 
567 	return 0;
568 }
569 early_initcall(rockchip_init_usb_uart);
570 
571 static int __init rockchip_usb_uart(char *buf)
572 {
573 	enable_usb_uart = true;
574 	return 0;
575 }
576 early_param("rockchip.usb_uart", rockchip_usb_uart);
577 #endif
578 
579 MODULE_AUTHOR("Yunzhi Li <lyz@rock-chips.com>");
580 MODULE_DESCRIPTION("Rockchip USB 2.0 PHY driver");
581 MODULE_LICENSE("GPL v2");
582