1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * USB Glue for Amlogic G12A SoCs
4  *
5  * Copyright (c) 2019 BayLibre, SAS
6  * Author: Neil Armstrong <narmstrong@baylibre.com>
7  */
8 
9 /*
10  * The USB is organized with a glue around the DWC3 Controller IP as :
11  * - Control registers for each USB2 Ports
12  * - Control registers for the USB PHY layer
13  * - SuperSpeed PHY can be enabled only if port is used
14  * - Dynamic OTG switching with ID change interrupt
15  */
16 
17 #include <linux/module.h>
18 #include <linux/kernel.h>
19 #include <linux/platform_device.h>
20 #include <linux/clk.h>
21 #include <linux/of.h>
22 #include <linux/of_platform.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/regmap.h>
25 #include <linux/bitfield.h>
26 #include <linux/bitops.h>
27 #include <linux/reset.h>
28 #include <linux/phy/phy.h>
29 #include <linux/usb/otg.h>
30 #include <linux/usb/role.h>
31 #include <linux/regulator/consumer.h>
32 
33 /* USB2 Ports Control Registers, offsets are per-port */
34 
35 #define U2P_REG_SIZE						0x20
36 
37 #define U2P_R0							0x0
38 	#define U2P_R0_HOST_DEVICE				BIT(0)
39 	#define U2P_R0_POWER_OK					BIT(1)
40 	#define U2P_R0_HAST_MODE				BIT(2)
41 	#define U2P_R0_POWER_ON_RESET				BIT(3)
42 	#define U2P_R0_ID_PULLUP				BIT(4)
43 	#define U2P_R0_DRV_VBUS					BIT(5)
44 
45 #define U2P_R1							0x4
46 	#define U2P_R1_PHY_READY				BIT(0)
47 	#define U2P_R1_ID_DIG					BIT(1)
48 	#define U2P_R1_OTG_SESSION_VALID			BIT(2)
49 	#define U2P_R1_VBUS_VALID				BIT(3)
50 
51 /* USB Glue Control Registers */
52 
53 #define G12A_GLUE_OFFSET					0x80
54 
55 #define USB_R0							0x00
56 	#define USB_R0_P30_LANE0_TX2RX_LOOPBACK			BIT(17)
57 	#define USB_R0_P30_LANE0_EXT_PCLK_REQ			BIT(18)
58 	#define USB_R0_P30_PCS_RX_LOS_MASK_VAL_MASK		GENMASK(28, 19)
59 	#define USB_R0_U2D_SS_SCALEDOWN_MODE_MASK		GENMASK(30, 29)
60 	#define USB_R0_U2D_ACT					BIT(31)
61 
62 #define USB_R1							0x04
63 	#define USB_R1_U3H_BIGENDIAN_GS				BIT(0)
64 	#define USB_R1_U3H_PME_ENABLE				BIT(1)
65 	#define USB_R1_U3H_HUB_PORT_OVERCURRENT_MASK		GENMASK(4, 2)
66 	#define USB_R1_U3H_HUB_PORT_PERM_ATTACH_MASK		GENMASK(9, 7)
67 	#define USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK		GENMASK(13, 12)
68 	#define USB_R1_U3H_HOST_U3_PORT_DISABLE			BIT(16)
69 	#define USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT	BIT(17)
70 	#define USB_R1_U3H_HOST_MSI_ENABLE			BIT(18)
71 	#define USB_R1_U3H_FLADJ_30MHZ_REG_MASK			GENMASK(24, 19)
72 	#define USB_R1_P30_PCS_TX_SWING_FULL_MASK		GENMASK(31, 25)
73 
74 #define USB_R2							0x08
75 	#define USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK		GENMASK(25, 20)
76 	#define USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK		GENMASK(31, 26)
77 
78 #define USB_R3							0x0c
79 	#define USB_R3_P30_SSC_ENABLE				BIT(0)
80 	#define USB_R3_P30_SSC_RANGE_MASK			GENMASK(3, 1)
81 	#define USB_R3_P30_SSC_REF_CLK_SEL_MASK			GENMASK(12, 4)
82 	#define USB_R3_P30_REF_SSP_EN				BIT(13)
83 
84 #define USB_R4							0x10
85 	#define USB_R4_P21_PORT_RESET_0				BIT(0)
86 	#define USB_R4_P21_SLEEP_M0				BIT(1)
87 	#define USB_R4_MEM_PD_MASK				GENMASK(3, 2)
88 	#define USB_R4_P21_ONLY					BIT(4)
89 
90 #define USB_R5							0x14
91 	#define USB_R5_ID_DIG_SYNC				BIT(0)
92 	#define USB_R5_ID_DIG_REG				BIT(1)
93 	#define USB_R5_ID_DIG_CFG_MASK				GENMASK(3, 2)
94 	#define USB_R5_ID_DIG_EN_0				BIT(4)
95 	#define USB_R5_ID_DIG_EN_1				BIT(5)
96 	#define USB_R5_ID_DIG_CURR				BIT(6)
97 	#define USB_R5_ID_DIG_IRQ				BIT(7)
98 	#define USB_R5_ID_DIG_TH_MASK				GENMASK(15, 8)
99 	#define USB_R5_ID_DIG_CNT_MASK				GENMASK(23, 16)
100 
101 #define PHY_COUNT						3
102 #define USB2_OTG_PHY						1
103 
104 static struct clk_bulk_data meson_gxl_clocks[] = {
105 	{ .id = "usb_ctrl" },
106 	{ .id = "ddr" },
107 };
108 
109 static struct clk_bulk_data meson_g12a_clocks[] = {
110 	{ .id = NULL },
111 };
112 
113 static struct clk_bulk_data meson_a1_clocks[] = {
114 	{ .id = "usb_ctrl" },
115 	{ .id = "usb_bus" },
116 	{ .id = "xtal_usb_ctrl" },
117 };
118 
119 static const char * const meson_gxm_phy_names[] = {
120 	"usb2-phy0", "usb2-phy1", "usb2-phy2",
121 };
122 
123 static const char * const meson_g12a_phy_names[] = {
124 	"usb2-phy0", "usb2-phy1", "usb3-phy0",
125 };
126 
127 /*
128  * Amlogic A1 has a single physical PHY, in slot 1, but still has the
129  * two U2 PHY controls register blocks like G12A.
130  * AXG has the similar scheme, thus needs the same tweak.
131  * Handling the first PHY on slot 1 would need a large amount of code
132  * changes, and the current management is generic enough to handle it
133  * correctly when only the "usb2-phy1" phy is specified on-par with the
134  * DT bindings.
135  */
136 static const char * const meson_a1_phy_names[] = {
137 	"usb2-phy0", "usb2-phy1"
138 };
139 
140 struct dwc3_meson_g12a;
141 
142 struct dwc3_meson_g12a_drvdata {
143 	bool otg_phy_host_port_disable;
144 	struct clk_bulk_data *clks;
145 	int num_clks;
146 	const char * const *phy_names;
147 	int num_phys;
148 	int (*setup_regmaps)(struct dwc3_meson_g12a *priv, void __iomem *base);
149 	int (*usb2_init_phy)(struct dwc3_meson_g12a *priv, int i,
150 			     enum phy_mode mode);
151 	int (*set_phy_mode)(struct dwc3_meson_g12a *priv, int i,
152 			    enum phy_mode mode);
153 	int (*usb_init)(struct dwc3_meson_g12a *priv);
154 	int (*usb_post_init)(struct dwc3_meson_g12a *priv);
155 };
156 
157 static int dwc3_meson_gxl_setup_regmaps(struct dwc3_meson_g12a *priv,
158 					void __iomem *base);
159 static int dwc3_meson_g12a_setup_regmaps(struct dwc3_meson_g12a *priv,
160 					 void __iomem *base);
161 
162 static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
163 					 enum phy_mode mode);
164 static int dwc3_meson_gxl_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
165 					enum phy_mode mode);
166 
167 static int dwc3_meson_g12a_set_phy_mode(struct dwc3_meson_g12a *priv,
168 					int i, enum phy_mode mode);
169 static int dwc3_meson_gxl_set_phy_mode(struct dwc3_meson_g12a *priv,
170 				       int i, enum phy_mode mode);
171 
172 static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv);
173 static int dwc3_meson_gxl_usb_init(struct dwc3_meson_g12a *priv);
174 
175 static int dwc3_meson_gxl_usb_post_init(struct dwc3_meson_g12a *priv);
176 
177 /*
178  * For GXL and GXM SoCs:
179  * USB Phy muxing between the DWC2 Device controller and the DWC3 Host
180  * controller is buggy when switching from Device to Host when USB port
181  * is unpopulated, it causes the DWC3 to hard crash.
182  * When populated (including OTG switching with ID pin), the switch works
183  * like a charm like on the G12A platforms.
184  * In order to still switch from Host to Device on an USB Type-A port,
185  * an U2_PORT_DISABLE bit has been added to disconnect the DWC3 Host
186  * controller from the port, but when used the DWC3 controller must be
187  * reset to recover usage of the port.
188  */
189 
190 static const struct dwc3_meson_g12a_drvdata gxl_drvdata = {
191 	.otg_phy_host_port_disable = true,
192 	.clks = meson_gxl_clocks,
193 	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
194 	.phy_names = meson_a1_phy_names,
195 	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
196 	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
197 	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
198 	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
199 	.usb_init = dwc3_meson_gxl_usb_init,
200 	.usb_post_init = dwc3_meson_gxl_usb_post_init,
201 };
202 
203 static const struct dwc3_meson_g12a_drvdata gxm_drvdata = {
204 	.otg_phy_host_port_disable = true,
205 	.clks = meson_gxl_clocks,
206 	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
207 	.phy_names = meson_gxm_phy_names,
208 	.num_phys = ARRAY_SIZE(meson_gxm_phy_names),
209 	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
210 	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
211 	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
212 	.usb_init = dwc3_meson_gxl_usb_init,
213 	.usb_post_init = dwc3_meson_gxl_usb_post_init,
214 };
215 
216 static const struct dwc3_meson_g12a_drvdata axg_drvdata = {
217 	.clks = meson_gxl_clocks,
218 	.num_clks = ARRAY_SIZE(meson_gxl_clocks),
219 	.phy_names = meson_a1_phy_names,
220 	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
221 	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
222 	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
223 	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
224 	.usb_init = dwc3_meson_g12a_usb_init,
225 	.usb_post_init = dwc3_meson_gxl_usb_post_init,
226 };
227 
228 static const struct dwc3_meson_g12a_drvdata g12a_drvdata = {
229 	.clks = meson_g12a_clocks,
230 	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
231 	.phy_names = meson_g12a_phy_names,
232 	.num_phys = ARRAY_SIZE(meson_g12a_phy_names),
233 	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
234 	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
235 	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
236 	.usb_init = dwc3_meson_g12a_usb_init,
237 };
238 
239 static const struct dwc3_meson_g12a_drvdata a1_drvdata = {
240 	.clks = meson_a1_clocks,
241 	.num_clks = ARRAY_SIZE(meson_a1_clocks),
242 	.phy_names = meson_a1_phy_names,
243 	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
244 	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
245 	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
246 	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
247 	.usb_init = dwc3_meson_g12a_usb_init,
248 };
249 
250 struct dwc3_meson_g12a {
251 	struct device		*dev;
252 	struct regmap		*u2p_regmap[PHY_COUNT];
253 	struct regmap		*usb_glue_regmap;
254 	struct reset_control	*reset;
255 	struct phy		*phys[PHY_COUNT];
256 	enum usb_dr_mode	otg_mode;
257 	enum phy_mode		otg_phy_mode;
258 	unsigned int		usb2_ports;
259 	unsigned int		usb3_ports;
260 	struct regulator	*vbus;
261 	struct usb_role_switch_desc switch_desc;
262 	struct usb_role_switch	*role_switch;
263 	const struct dwc3_meson_g12a_drvdata *drvdata;
264 };
265 
266 static int dwc3_meson_gxl_set_phy_mode(struct dwc3_meson_g12a *priv,
267 					 int i, enum phy_mode mode)
268 {
269 	return phy_set_mode(priv->phys[i], mode);
270 }
271 
272 static int dwc3_meson_gxl_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
273 					enum phy_mode mode)
274 {
275 	/* On GXL PHY must be started in device mode for DWC2 init */
276 	return priv->drvdata->set_phy_mode(priv, i,
277 				(i == USB2_OTG_PHY) ? PHY_MODE_USB_DEVICE
278 						    : PHY_MODE_USB_HOST);
279 }
280 
281 static int dwc3_meson_g12a_set_phy_mode(struct dwc3_meson_g12a *priv,
282 					 int i, enum phy_mode mode)
283 {
284 	if (mode == PHY_MODE_USB_HOST)
285 		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
286 				U2P_R0_HOST_DEVICE,
287 				U2P_R0_HOST_DEVICE);
288 	else
289 		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
290 				U2P_R0_HOST_DEVICE, 0);
291 
292 	return 0;
293 }
294 
295 static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
296 					 enum phy_mode mode)
297 {
298 	int ret;
299 
300 	regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
301 			U2P_R0_POWER_ON_RESET,
302 			U2P_R0_POWER_ON_RESET);
303 
304 	if (i == USB2_OTG_PHY) {
305 		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
306 				   U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS,
307 				   U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS);
308 
309 		ret = priv->drvdata->set_phy_mode(priv, i, mode);
310 	} else
311 		ret = priv->drvdata->set_phy_mode(priv, i,
312 						  PHY_MODE_USB_HOST);
313 
314 	if (ret)
315 		return ret;
316 
317 	regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
318 			U2P_R0_POWER_ON_RESET, 0);
319 
320 	return 0;
321 }
322 
323 static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv,
324 				     enum phy_mode mode)
325 {
326 	int i, ret;
327 
328 	for (i = 0; i < priv->drvdata->num_phys; ++i) {
329 		if (!priv->phys[i])
330 			continue;
331 
332 		if (!strstr(priv->drvdata->phy_names[i], "usb2"))
333 			continue;
334 
335 		ret = priv->drvdata->usb2_init_phy(priv, i, mode);
336 		if (ret)
337 			return ret;
338 	}
339 
340 	return 0;
341 }
342 
343 static void dwc3_meson_g12a_usb3_init(struct dwc3_meson_g12a *priv)
344 {
345 	regmap_update_bits(priv->usb_glue_regmap, USB_R3,
346 			USB_R3_P30_SSC_RANGE_MASK |
347 			USB_R3_P30_REF_SSP_EN,
348 			USB_R3_P30_SSC_ENABLE |
349 			FIELD_PREP(USB_R3_P30_SSC_RANGE_MASK, 2) |
350 			USB_R3_P30_REF_SSP_EN);
351 	udelay(2);
352 
353 	regmap_update_bits(priv->usb_glue_regmap, USB_R2,
354 			USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK,
355 			FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK, 0x15));
356 
357 	regmap_update_bits(priv->usb_glue_regmap, USB_R2,
358 			USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK,
359 			FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK, 0x20));
360 
361 	udelay(2);
362 
363 	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
364 			USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT,
365 			USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT);
366 
367 	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
368 			USB_R1_P30_PCS_TX_SWING_FULL_MASK,
369 			FIELD_PREP(USB_R1_P30_PCS_TX_SWING_FULL_MASK, 127));
370 }
371 
372 static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv,
373 					       enum phy_mode mode)
374 {
375 	if (mode == PHY_MODE_USB_DEVICE) {
376 		if (priv->otg_mode != USB_DR_MODE_OTG &&
377 		    priv->drvdata->otg_phy_host_port_disable)
378 			/* Isolate the OTG PHY port from the Host Controller */
379 			regmap_update_bits(priv->usb_glue_regmap, USB_R1,
380 				USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK,
381 				FIELD_PREP(USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK,
382 					   BIT(USB2_OTG_PHY)));
383 
384 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
385 				USB_R0_U2D_ACT, USB_R0_U2D_ACT);
386 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
387 				USB_R0_U2D_SS_SCALEDOWN_MODE_MASK, 0);
388 		regmap_update_bits(priv->usb_glue_regmap, USB_R4,
389 				USB_R4_P21_SLEEP_M0, USB_R4_P21_SLEEP_M0);
390 	} else {
391 		if (priv->otg_mode != USB_DR_MODE_OTG &&
392 		    priv->drvdata->otg_phy_host_port_disable) {
393 			regmap_update_bits(priv->usb_glue_regmap, USB_R1,
394 				USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK, 0);
395 			msleep(500);
396 		}
397 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
398 				USB_R0_U2D_ACT, 0);
399 		regmap_update_bits(priv->usb_glue_regmap, USB_R4,
400 				USB_R4_P21_SLEEP_M0, 0);
401 	}
402 }
403 
404 static int dwc3_meson_g12a_usb_init_glue(struct dwc3_meson_g12a *priv,
405 					 enum phy_mode mode)
406 {
407 	int ret;
408 
409 	ret = dwc3_meson_g12a_usb2_init(priv, mode);
410 	if (ret)
411 		return ret;
412 
413 	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
414 			USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
415 			FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
416 
417 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
418 			USB_R5_ID_DIG_EN_0,
419 			USB_R5_ID_DIG_EN_0);
420 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
421 			USB_R5_ID_DIG_EN_1,
422 			USB_R5_ID_DIG_EN_1);
423 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
424 			USB_R5_ID_DIG_TH_MASK,
425 			FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
426 
427 	/* If we have an actual SuperSpeed port, initialize it */
428 	if (priv->usb3_ports)
429 		dwc3_meson_g12a_usb3_init(priv);
430 
431 	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);
432 
433 	return 0;
434 }
435 
436 static const struct regmap_config phy_meson_g12a_usb_glue_regmap_conf = {
437 	.name = "usb-glue",
438 	.reg_bits = 8,
439 	.val_bits = 32,
440 	.reg_stride = 4,
441 	.max_register = USB_R5,
442 };
443 
444 static int dwc3_meson_g12a_get_phys(struct dwc3_meson_g12a *priv)
445 {
446 	const char *phy_name;
447 	int i;
448 
449 	for (i = 0 ; i < priv->drvdata->num_phys ; ++i) {
450 		phy_name = priv->drvdata->phy_names[i];
451 		priv->phys[i] = devm_phy_optional_get(priv->dev, phy_name);
452 		if (!priv->phys[i])
453 			continue;
454 
455 		if (IS_ERR(priv->phys[i]))
456 			return PTR_ERR(priv->phys[i]);
457 
458 		if (strstr(phy_name, "usb3"))
459 			priv->usb3_ports++;
460 		else
461 			priv->usb2_ports++;
462 	}
463 
464 	dev_info(priv->dev, "USB2 ports: %d\n", priv->usb2_ports);
465 	dev_info(priv->dev, "USB3 ports: %d\n", priv->usb3_ports);
466 
467 	return 0;
468 }
469 
470 static enum phy_mode dwc3_meson_g12a_get_id(struct dwc3_meson_g12a *priv)
471 {
472 	u32 reg;
473 
474 	regmap_read(priv->usb_glue_regmap, USB_R5, &reg);
475 
476 	if (reg & (USB_R5_ID_DIG_SYNC | USB_R5_ID_DIG_REG))
477 		return PHY_MODE_USB_DEVICE;
478 
479 	return PHY_MODE_USB_HOST;
480 }
481 
482 static int dwc3_meson_g12a_otg_mode_set(struct dwc3_meson_g12a *priv,
483 					enum phy_mode mode)
484 {
485 	int ret;
486 
487 	if (!priv->phys[USB2_OTG_PHY])
488 		return -EINVAL;
489 
490 	if (mode == PHY_MODE_USB_HOST)
491 		dev_info(priv->dev, "switching to Host Mode\n");
492 	else
493 		dev_info(priv->dev, "switching to Device Mode\n");
494 
495 	if (priv->vbus) {
496 		if (mode == PHY_MODE_USB_DEVICE)
497 			ret = regulator_disable(priv->vbus);
498 		else
499 			ret = regulator_enable(priv->vbus);
500 		if (ret)
501 			return ret;
502 	}
503 
504 	priv->otg_phy_mode = mode;
505 
506 	ret = priv->drvdata->set_phy_mode(priv, USB2_OTG_PHY, mode);
507 	if (ret)
508 		return ret;
509 
510 	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);
511 
512 	return 0;
513 }
514 
515 static int dwc3_meson_g12a_role_set(struct usb_role_switch *sw,
516 				    enum usb_role role)
517 {
518 	struct dwc3_meson_g12a *priv = usb_role_switch_get_drvdata(sw);
519 	enum phy_mode mode;
520 
521 	if (role == USB_ROLE_NONE)
522 		return 0;
523 
524 	mode = (role == USB_ROLE_HOST) ? PHY_MODE_USB_HOST
525 				       : PHY_MODE_USB_DEVICE;
526 
527 	if (mode == priv->otg_phy_mode)
528 		return 0;
529 
530 	if (priv->drvdata->otg_phy_host_port_disable)
531 		dev_warn_once(priv->dev, "Broken manual OTG switch\n");
532 
533 	return dwc3_meson_g12a_otg_mode_set(priv, mode);
534 }
535 
536 static enum usb_role dwc3_meson_g12a_role_get(struct usb_role_switch *sw)
537 {
538 	struct dwc3_meson_g12a *priv = usb_role_switch_get_drvdata(sw);
539 
540 	return priv->otg_phy_mode == PHY_MODE_USB_HOST ?
541 		USB_ROLE_HOST : USB_ROLE_DEVICE;
542 }
543 
544 static irqreturn_t dwc3_meson_g12a_irq_thread(int irq, void *data)
545 {
546 	struct dwc3_meson_g12a *priv = data;
547 	enum phy_mode otg_id;
548 
549 	otg_id = dwc3_meson_g12a_get_id(priv);
550 	if (otg_id != priv->otg_phy_mode) {
551 		if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
552 			dev_warn(priv->dev, "Failed to switch OTG mode\n");
553 	}
554 
555 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
556 			   USB_R5_ID_DIG_IRQ, 0);
557 
558 	return IRQ_HANDLED;
559 }
560 
561 static struct device *dwc3_meson_g12_find_child(struct device *dev,
562 						const char *compatible)
563 {
564 	struct platform_device *pdev;
565 	struct device_node *np;
566 
567 	np = of_get_compatible_child(dev->of_node, compatible);
568 	if (!np)
569 		return NULL;
570 
571 	pdev = of_find_device_by_node(np);
572 	of_node_put(np);
573 	if (!pdev)
574 		return NULL;
575 
576 	return &pdev->dev;
577 }
578 
579 static int dwc3_meson_g12a_otg_init(struct platform_device *pdev,
580 				    struct dwc3_meson_g12a *priv)
581 {
582 	enum phy_mode otg_id;
583 	int ret, irq;
584 	struct device *dev = &pdev->dev;
585 
586 	if (priv->otg_mode == USB_DR_MODE_OTG) {
587 		/* Ack irq before registering */
588 		regmap_update_bits(priv->usb_glue_regmap, USB_R5,
589 				   USB_R5_ID_DIG_IRQ, 0);
590 
591 		irq = platform_get_irq(pdev, 0);
592 		if (irq < 0)
593 			return irq;
594 		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
595 						dwc3_meson_g12a_irq_thread,
596 						IRQF_ONESHOT, pdev->name, priv);
597 		if (ret)
598 			return ret;
599 	}
600 
601 	/* Setup OTG mode corresponding to the ID pin */
602 	if (priv->otg_mode == USB_DR_MODE_OTG) {
603 		otg_id = dwc3_meson_g12a_get_id(priv);
604 		if (otg_id != priv->otg_phy_mode) {
605 			if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
606 				dev_warn(dev, "Failed to switch OTG mode\n");
607 		}
608 	}
609 
610 	/* Setup role switcher */
611 	priv->switch_desc.usb2_port = dwc3_meson_g12_find_child(dev,
612 								"snps,dwc3");
613 	priv->switch_desc.udc = dwc3_meson_g12_find_child(dev, "snps,dwc2");
614 	priv->switch_desc.allow_userspace_control = true;
615 	priv->switch_desc.set = dwc3_meson_g12a_role_set;
616 	priv->switch_desc.get = dwc3_meson_g12a_role_get;
617 	priv->switch_desc.driver_data = priv;
618 
619 	priv->role_switch = usb_role_switch_register(dev, &priv->switch_desc);
620 	if (IS_ERR(priv->role_switch))
621 		dev_warn(dev, "Unable to register Role Switch\n");
622 
623 	return 0;
624 }
625 
626 static int dwc3_meson_gxl_setup_regmaps(struct dwc3_meson_g12a *priv,
627 					void __iomem *base)
628 {
629 	/* GXL controls the PHY mode in the PHY registers unlike G12A */
630 	priv->usb_glue_regmap = devm_regmap_init_mmio(priv->dev, base,
631 					&phy_meson_g12a_usb_glue_regmap_conf);
632 	return PTR_ERR_OR_ZERO(priv->usb_glue_regmap);
633 }
634 
635 static int dwc3_meson_g12a_setup_regmaps(struct dwc3_meson_g12a *priv,
636 					 void __iomem *base)
637 {
638 	int i;
639 
640 	priv->usb_glue_regmap = devm_regmap_init_mmio(priv->dev,
641 					base + G12A_GLUE_OFFSET,
642 					&phy_meson_g12a_usb_glue_regmap_conf);
643 	if (IS_ERR(priv->usb_glue_regmap))
644 		return PTR_ERR(priv->usb_glue_regmap);
645 
646 	/* Create a regmap for each USB2 PHY control register set */
647 	for (i = 0; i < priv->drvdata->num_phys; i++) {
648 		struct regmap_config u2p_regmap_config = {
649 			.reg_bits = 8,
650 			.val_bits = 32,
651 			.reg_stride = 4,
652 			.max_register = U2P_R1,
653 		};
654 
655 		if (!strstr(priv->drvdata->phy_names[i], "usb2"))
656 			continue;
657 
658 		u2p_regmap_config.name = devm_kasprintf(priv->dev, GFP_KERNEL,
659 							"u2p-%d", i);
660 		if (!u2p_regmap_config.name)
661 			return -ENOMEM;
662 
663 		priv->u2p_regmap[i] = devm_regmap_init_mmio(priv->dev,
664 						base + (i * U2P_REG_SIZE),
665 						&u2p_regmap_config);
666 		if (IS_ERR(priv->u2p_regmap[i]))
667 			return PTR_ERR(priv->u2p_regmap[i]);
668 	}
669 
670 	return 0;
671 }
672 
673 static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
674 {
675 	return dwc3_meson_g12a_usb_init_glue(priv, priv->otg_phy_mode);
676 }
677 
678 static int dwc3_meson_gxl_usb_init(struct dwc3_meson_g12a *priv)
679 {
680 	return dwc3_meson_g12a_usb_init_glue(priv, PHY_MODE_USB_DEVICE);
681 }
682 
683 static int dwc3_meson_gxl_usb_post_init(struct dwc3_meson_g12a *priv)
684 {
685 	int ret;
686 
687 	ret = priv->drvdata->set_phy_mode(priv, USB2_OTG_PHY,
688 					  priv->otg_phy_mode);
689 	if (ret)
690 		return ret;
691 
692 	dwc3_meson_g12a_usb_otg_apply_mode(priv, priv->otg_phy_mode);
693 
694 	return 0;
695 }
696 
697 static int dwc3_meson_g12a_probe(struct platform_device *pdev)
698 {
699 	struct dwc3_meson_g12a	*priv;
700 	struct device		*dev = &pdev->dev;
701 	struct device_node	*np = dev->of_node;
702 	void __iomem *base;
703 	int ret, i;
704 
705 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
706 	if (!priv)
707 		return -ENOMEM;
708 
709 	base = devm_platform_ioremap_resource(pdev, 0);
710 	if (IS_ERR(base))
711 		return PTR_ERR(base);
712 
713 	priv->drvdata = of_device_get_match_data(&pdev->dev);
714 	priv->dev = dev;
715 
716 	priv->vbus = devm_regulator_get_optional(dev, "vbus");
717 	if (IS_ERR(priv->vbus)) {
718 		if (PTR_ERR(priv->vbus) == -EPROBE_DEFER)
719 			return PTR_ERR(priv->vbus);
720 		priv->vbus = NULL;
721 	}
722 
723 	ret = devm_clk_bulk_get(dev,
724 				priv->drvdata->num_clks,
725 				priv->drvdata->clks);
726 	if (ret)
727 		return ret;
728 
729 	ret = clk_bulk_prepare_enable(priv->drvdata->num_clks,
730 				      priv->drvdata->clks);
731 	if (ret)
732 		return ret;
733 
734 	platform_set_drvdata(pdev, priv);
735 
736 	priv->reset = devm_reset_control_get_shared(dev, NULL);
737 	if (IS_ERR(priv->reset)) {
738 		ret = PTR_ERR(priv->reset);
739 		dev_err(dev, "failed to get device reset, err=%d\n", ret);
740 		goto err_disable_clks;
741 	}
742 
743 	ret = reset_control_reset(priv->reset);
744 	if (ret)
745 		goto err_disable_clks;
746 
747 	ret = dwc3_meson_g12a_get_phys(priv);
748 	if (ret)
749 		goto err_rearm;
750 
751 	ret = priv->drvdata->setup_regmaps(priv, base);
752 	if (ret)
753 		goto err_rearm;
754 
755 	if (priv->vbus) {
756 		ret = regulator_enable(priv->vbus);
757 		if (ret)
758 			goto err_rearm;
759 	}
760 
761 	/* Get dr_mode */
762 	priv->otg_mode = usb_get_dr_mode(dev);
763 
764 	if (priv->otg_mode == USB_DR_MODE_PERIPHERAL)
765 		priv->otg_phy_mode = PHY_MODE_USB_DEVICE;
766 	else
767 		priv->otg_phy_mode = PHY_MODE_USB_HOST;
768 
769 	ret = priv->drvdata->usb_init(priv);
770 	if (ret)
771 		goto err_disable_regulator;
772 
773 	/* Init PHYs */
774 	for (i = 0 ; i < PHY_COUNT ; ++i) {
775 		ret = phy_init(priv->phys[i]);
776 		if (ret)
777 			goto err_disable_regulator;
778 	}
779 
780 	/* Set PHY Power */
781 	for (i = 0 ; i < PHY_COUNT ; ++i) {
782 		ret = phy_power_on(priv->phys[i]);
783 		if (ret)
784 			goto err_phys_exit;
785 	}
786 
787 	if (priv->drvdata->usb_post_init) {
788 		ret = priv->drvdata->usb_post_init(priv);
789 		if (ret)
790 			goto err_phys_power;
791 	}
792 
793 	ret = of_platform_populate(np, NULL, NULL, dev);
794 	if (ret)
795 		goto err_phys_power;
796 
797 	ret = dwc3_meson_g12a_otg_init(pdev, priv);
798 	if (ret)
799 		goto err_plat_depopulate;
800 
801 	pm_runtime_set_active(dev);
802 	pm_runtime_enable(dev);
803 	pm_runtime_get_sync(dev);
804 
805 	return 0;
806 
807 err_plat_depopulate:
808 	of_platform_depopulate(dev);
809 
810 err_phys_power:
811 	for (i = 0 ; i < PHY_COUNT ; ++i)
812 		phy_power_off(priv->phys[i]);
813 
814 err_phys_exit:
815 	for (i = 0 ; i < PHY_COUNT ; ++i)
816 		phy_exit(priv->phys[i]);
817 
818 err_disable_regulator:
819 	if (priv->vbus)
820 		regulator_disable(priv->vbus);
821 
822 err_rearm:
823 	reset_control_rearm(priv->reset);
824 
825 err_disable_clks:
826 	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
827 				   priv->drvdata->clks);
828 
829 	return ret;
830 }
831 
832 static void dwc3_meson_g12a_remove(struct platform_device *pdev)
833 {
834 	struct dwc3_meson_g12a *priv = platform_get_drvdata(pdev);
835 	struct device *dev = &pdev->dev;
836 	int i;
837 
838 	usb_role_switch_unregister(priv->role_switch);
839 
840 	of_platform_depopulate(dev);
841 
842 	for (i = 0 ; i < PHY_COUNT ; ++i) {
843 		phy_power_off(priv->phys[i]);
844 		phy_exit(priv->phys[i]);
845 	}
846 
847 	pm_runtime_disable(dev);
848 	pm_runtime_put_noidle(dev);
849 	pm_runtime_set_suspended(dev);
850 
851 	reset_control_rearm(priv->reset);
852 
853 	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
854 				   priv->drvdata->clks);
855 }
856 
857 static int __maybe_unused dwc3_meson_g12a_runtime_suspend(struct device *dev)
858 {
859 	struct dwc3_meson_g12a	*priv = dev_get_drvdata(dev);
860 
861 	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
862 				   priv->drvdata->clks);
863 
864 	return 0;
865 }
866 
867 static int __maybe_unused dwc3_meson_g12a_runtime_resume(struct device *dev)
868 {
869 	struct dwc3_meson_g12a	*priv = dev_get_drvdata(dev);
870 
871 	return clk_bulk_prepare_enable(priv->drvdata->num_clks,
872 				       priv->drvdata->clks);
873 }
874 
875 static int __maybe_unused dwc3_meson_g12a_suspend(struct device *dev)
876 {
877 	struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
878 	int i, ret;
879 
880 	if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
881 		ret = regulator_disable(priv->vbus);
882 		if (ret)
883 			return ret;
884 	}
885 
886 	for (i = 0 ; i < PHY_COUNT ; ++i) {
887 		phy_power_off(priv->phys[i]);
888 		phy_exit(priv->phys[i]);
889 	}
890 
891 	reset_control_rearm(priv->reset);
892 
893 	return 0;
894 }
895 
896 static int __maybe_unused dwc3_meson_g12a_resume(struct device *dev)
897 {
898 	struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
899 	int i, ret;
900 
901 	ret = reset_control_reset(priv->reset);
902 	if (ret)
903 		return ret;
904 
905 	ret = priv->drvdata->usb_init(priv);
906 	if (ret)
907 		return ret;
908 
909 	/* Init PHYs */
910 	for (i = 0 ; i < PHY_COUNT ; ++i) {
911 		ret = phy_init(priv->phys[i]);
912 		if (ret)
913 			return ret;
914 	}
915 
916 	/* Set PHY Power */
917 	for (i = 0 ; i < PHY_COUNT ; ++i) {
918 		ret = phy_power_on(priv->phys[i]);
919 		if (ret)
920 			return ret;
921 	}
922 
923 	if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
924 		ret = regulator_enable(priv->vbus);
925 		if (ret)
926 			return ret;
927 	}
928 
929 	return 0;
930 }
931 
932 static const struct dev_pm_ops dwc3_meson_g12a_dev_pm_ops = {
933 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_meson_g12a_suspend, dwc3_meson_g12a_resume)
934 	SET_RUNTIME_PM_OPS(dwc3_meson_g12a_runtime_suspend,
935 			   dwc3_meson_g12a_runtime_resume, NULL)
936 };
937 
938 static const struct of_device_id dwc3_meson_g12a_match[] = {
939 	{
940 		.compatible = "amlogic,meson-gxl-usb-ctrl",
941 		.data = &gxl_drvdata,
942 	},
943 	{
944 		.compatible = "amlogic,meson-gxm-usb-ctrl",
945 		.data = &gxm_drvdata,
946 	},
947 	{
948 		.compatible = "amlogic,meson-axg-usb-ctrl",
949 		.data = &axg_drvdata,
950 	},
951 	{
952 		.compatible = "amlogic,meson-g12a-usb-ctrl",
953 		.data = &g12a_drvdata,
954 	},
955 	{
956 		.compatible = "amlogic,meson-a1-usb-ctrl",
957 		.data = &a1_drvdata,
958 	},
959 	{ /* Sentinel */ }
960 };
961 MODULE_DEVICE_TABLE(of, dwc3_meson_g12a_match);
962 
963 static struct platform_driver dwc3_meson_g12a_driver = {
964 	.probe		= dwc3_meson_g12a_probe,
965 	.remove_new	= dwc3_meson_g12a_remove,
966 	.driver		= {
967 		.name	= "dwc3-meson-g12a",
968 		.of_match_table = dwc3_meson_g12a_match,
969 		.pm	= &dwc3_meson_g12a_dev_pm_ops,
970 	},
971 };
972 
973 module_platform_driver(dwc3_meson_g12a_driver);
974 MODULE_LICENSE("GPL v2");
975 MODULE_DESCRIPTION("Amlogic Meson G12A USB Glue Layer");
976 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
977