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 *meson_gxm_phy_names[] = {
120 	"usb2-phy0", "usb2-phy1", "usb2-phy2",
121 };
122 
123 static const char *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  * Handling the first PHY on slot 1 would need a large amount of code
131  * changes, and the current management is generic enough to handle it
132  * correctly when only the "usb2-phy1" phy is specified on-par with the
133  * DT bindings.
134  */
135 static const char *meson_a1_phy_names[] = {
136 	"usb2-phy0", "usb2-phy1"
137 };
138 
139 struct dwc3_meson_g12a;
140 
141 struct dwc3_meson_g12a_drvdata {
142 	bool otg_switch_supported;
143 	bool otg_phy_host_port_disable;
144 	struct clk_bulk_data *clks;
145 	int num_clks;
146 	const char **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 struct dwc3_meson_g12a_drvdata gxl_drvdata = {
191 	.otg_switch_supported = true,
192 	.otg_phy_host_port_disable = true,
193 	.clks = meson_gxl_clocks,
194 	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
195 	.phy_names = meson_a1_phy_names,
196 	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
197 	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
198 	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
199 	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
200 	.usb_init = dwc3_meson_gxl_usb_init,
201 	.usb_post_init = dwc3_meson_gxl_usb_post_init,
202 };
203 
204 static struct dwc3_meson_g12a_drvdata gxm_drvdata = {
205 	.otg_switch_supported = true,
206 	.otg_phy_host_port_disable = true,
207 	.clks = meson_gxl_clocks,
208 	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
209 	.phy_names = meson_gxm_phy_names,
210 	.num_phys = ARRAY_SIZE(meson_gxm_phy_names),
211 	.setup_regmaps = dwc3_meson_gxl_setup_regmaps,
212 	.usb2_init_phy = dwc3_meson_gxl_usb2_init_phy,
213 	.set_phy_mode = dwc3_meson_gxl_set_phy_mode,
214 	.usb_init = dwc3_meson_gxl_usb_init,
215 	.usb_post_init = dwc3_meson_gxl_usb_post_init,
216 };
217 
218 static struct dwc3_meson_g12a_drvdata g12a_drvdata = {
219 	.otg_switch_supported = true,
220 	.clks = meson_g12a_clocks,
221 	.num_clks = ARRAY_SIZE(meson_g12a_clocks),
222 	.phy_names = meson_g12a_phy_names,
223 	.num_phys = ARRAY_SIZE(meson_g12a_phy_names),
224 	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
225 	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
226 	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
227 	.usb_init = dwc3_meson_g12a_usb_init,
228 };
229 
230 static struct dwc3_meson_g12a_drvdata a1_drvdata = {
231 	.otg_switch_supported = false,
232 	.clks = meson_a1_clocks,
233 	.num_clks = ARRAY_SIZE(meson_a1_clocks),
234 	.phy_names = meson_a1_phy_names,
235 	.num_phys = ARRAY_SIZE(meson_a1_phy_names),
236 	.setup_regmaps = dwc3_meson_g12a_setup_regmaps,
237 	.usb2_init_phy = dwc3_meson_g12a_usb2_init_phy,
238 	.set_phy_mode = dwc3_meson_g12a_set_phy_mode,
239 	.usb_init = dwc3_meson_g12a_usb_init,
240 };
241 
242 struct dwc3_meson_g12a {
243 	struct device		*dev;
244 	struct regmap		*u2p_regmap[PHY_COUNT];
245 	struct regmap		*usb_glue_regmap;
246 	struct reset_control	*reset;
247 	struct phy		*phys[PHY_COUNT];
248 	enum usb_dr_mode	otg_mode;
249 	enum phy_mode		otg_phy_mode;
250 	unsigned int		usb2_ports;
251 	unsigned int		usb3_ports;
252 	struct regulator	*vbus;
253 	struct usb_role_switch_desc switch_desc;
254 	struct usb_role_switch	*role_switch;
255 	const struct dwc3_meson_g12a_drvdata *drvdata;
256 };
257 
258 static int dwc3_meson_gxl_set_phy_mode(struct dwc3_meson_g12a *priv,
259 					 int i, enum phy_mode mode)
260 {
261 	return phy_set_mode(priv->phys[i], mode);
262 }
263 
264 static int dwc3_meson_gxl_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
265 					enum phy_mode mode)
266 {
267 	/* On GXL PHY must be started in device mode for DWC2 init */
268 	return priv->drvdata->set_phy_mode(priv, i,
269 				(i == USB2_OTG_PHY) ? PHY_MODE_USB_DEVICE
270 						    : PHY_MODE_USB_HOST);
271 }
272 
273 static int dwc3_meson_g12a_set_phy_mode(struct dwc3_meson_g12a *priv,
274 					 int i, enum phy_mode mode)
275 {
276 	if (mode == PHY_MODE_USB_HOST)
277 		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
278 				U2P_R0_HOST_DEVICE,
279 				U2P_R0_HOST_DEVICE);
280 	else
281 		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
282 				U2P_R0_HOST_DEVICE, 0);
283 
284 	return 0;
285 }
286 
287 static int dwc3_meson_g12a_usb2_init_phy(struct dwc3_meson_g12a *priv, int i,
288 					 enum phy_mode mode)
289 {
290 	int ret;
291 
292 	regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
293 			U2P_R0_POWER_ON_RESET,
294 			U2P_R0_POWER_ON_RESET);
295 
296 	if (priv->drvdata->otg_switch_supported && i == USB2_OTG_PHY) {
297 		regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
298 				   U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS,
299 				   U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS);
300 
301 		ret = priv->drvdata->set_phy_mode(priv, i, mode);
302 	} else
303 		ret = priv->drvdata->set_phy_mode(priv, i,
304 						  PHY_MODE_USB_HOST);
305 
306 	if (ret)
307 		return ret;
308 
309 	regmap_update_bits(priv->u2p_regmap[i], U2P_R0,
310 			U2P_R0_POWER_ON_RESET, 0);
311 
312 	return 0;
313 }
314 
315 static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv,
316 				     enum phy_mode mode)
317 {
318 	int i, ret;
319 
320 	for (i = 0; i < priv->drvdata->num_phys; ++i) {
321 		if (!priv->phys[i])
322 			continue;
323 
324 		if (!strstr(priv->drvdata->phy_names[i], "usb2"))
325 			continue;
326 
327 		ret = priv->drvdata->usb2_init_phy(priv, i, mode);
328 		if (ret)
329 			return ret;
330 	}
331 
332 	return 0;
333 }
334 
335 static void dwc3_meson_g12a_usb3_init(struct dwc3_meson_g12a *priv)
336 {
337 	regmap_update_bits(priv->usb_glue_regmap, USB_R3,
338 			USB_R3_P30_SSC_RANGE_MASK |
339 			USB_R3_P30_REF_SSP_EN,
340 			USB_R3_P30_SSC_ENABLE |
341 			FIELD_PREP(USB_R3_P30_SSC_RANGE_MASK, 2) |
342 			USB_R3_P30_REF_SSP_EN);
343 	udelay(2);
344 
345 	regmap_update_bits(priv->usb_glue_regmap, USB_R2,
346 			USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK,
347 			FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK, 0x15));
348 
349 	regmap_update_bits(priv->usb_glue_regmap, USB_R2,
350 			USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK,
351 			FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK, 0x20));
352 
353 	udelay(2);
354 
355 	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
356 			USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT,
357 			USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT);
358 
359 	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
360 			USB_R1_P30_PCS_TX_SWING_FULL_MASK,
361 			FIELD_PREP(USB_R1_P30_PCS_TX_SWING_FULL_MASK, 127));
362 }
363 
364 static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv,
365 					       enum phy_mode mode)
366 {
367 	if (mode == PHY_MODE_USB_DEVICE) {
368 		if (priv->otg_mode != USB_DR_MODE_OTG &&
369 		    priv->drvdata->otg_phy_host_port_disable)
370 			/* Isolate the OTG PHY port from the Host Controller */
371 			regmap_update_bits(priv->usb_glue_regmap, USB_R1,
372 				USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK,
373 				FIELD_PREP(USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK,
374 					   BIT(USB2_OTG_PHY)));
375 
376 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
377 				USB_R0_U2D_ACT, USB_R0_U2D_ACT);
378 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
379 				USB_R0_U2D_SS_SCALEDOWN_MODE_MASK, 0);
380 		regmap_update_bits(priv->usb_glue_regmap, USB_R4,
381 				USB_R4_P21_SLEEP_M0, USB_R4_P21_SLEEP_M0);
382 	} else {
383 		if (priv->otg_mode != USB_DR_MODE_OTG &&
384 		    priv->drvdata->otg_phy_host_port_disable) {
385 			regmap_update_bits(priv->usb_glue_regmap, USB_R1,
386 				USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK, 0);
387 			msleep(500);
388 		}
389 		regmap_update_bits(priv->usb_glue_regmap, USB_R0,
390 				USB_R0_U2D_ACT, 0);
391 		regmap_update_bits(priv->usb_glue_regmap, USB_R4,
392 				USB_R4_P21_SLEEP_M0, 0);
393 	}
394 }
395 
396 static int dwc3_meson_g12a_usb_init_glue(struct dwc3_meson_g12a *priv,
397 					 enum phy_mode mode)
398 {
399 	int ret;
400 
401 	ret = dwc3_meson_g12a_usb2_init(priv, mode);
402 	if (ret)
403 		return ret;
404 
405 	regmap_update_bits(priv->usb_glue_regmap, USB_R1,
406 			USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
407 			FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
408 
409 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
410 			USB_R5_ID_DIG_EN_0,
411 			USB_R5_ID_DIG_EN_0);
412 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
413 			USB_R5_ID_DIG_EN_1,
414 			USB_R5_ID_DIG_EN_1);
415 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
416 			USB_R5_ID_DIG_TH_MASK,
417 			FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
418 
419 	/* If we have an actual SuperSpeed port, initialize it */
420 	if (priv->usb3_ports)
421 		dwc3_meson_g12a_usb3_init(priv);
422 
423 	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);
424 
425 	return 0;
426 }
427 
428 static const struct regmap_config phy_meson_g12a_usb_glue_regmap_conf = {
429 	.name = "usb-glue",
430 	.reg_bits = 8,
431 	.val_bits = 32,
432 	.reg_stride = 4,
433 	.max_register = USB_R5,
434 };
435 
436 static int dwc3_meson_g12a_get_phys(struct dwc3_meson_g12a *priv)
437 {
438 	const char *phy_name;
439 	int i;
440 
441 	for (i = 0 ; i < priv->drvdata->num_phys ; ++i) {
442 		phy_name = priv->drvdata->phy_names[i];
443 		priv->phys[i] = devm_phy_optional_get(priv->dev, phy_name);
444 		if (!priv->phys[i])
445 			continue;
446 
447 		if (IS_ERR(priv->phys[i]))
448 			return PTR_ERR(priv->phys[i]);
449 
450 		if (strstr(phy_name, "usb3"))
451 			priv->usb3_ports++;
452 		else
453 			priv->usb2_ports++;
454 	}
455 
456 	dev_info(priv->dev, "USB2 ports: %d\n", priv->usb2_ports);
457 	dev_info(priv->dev, "USB3 ports: %d\n", priv->usb3_ports);
458 
459 	return 0;
460 }
461 
462 static enum phy_mode dwc3_meson_g12a_get_id(struct dwc3_meson_g12a *priv)
463 {
464 	u32 reg;
465 
466 	regmap_read(priv->usb_glue_regmap, USB_R5, &reg);
467 
468 	if (reg & (USB_R5_ID_DIG_SYNC | USB_R5_ID_DIG_REG))
469 		return PHY_MODE_USB_DEVICE;
470 
471 	return PHY_MODE_USB_HOST;
472 }
473 
474 static int dwc3_meson_g12a_otg_mode_set(struct dwc3_meson_g12a *priv,
475 					enum phy_mode mode)
476 {
477 	int ret;
478 
479 	if (!priv->drvdata->otg_switch_supported || !priv->phys[USB2_OTG_PHY])
480 		return -EINVAL;
481 
482 	if (mode == PHY_MODE_USB_HOST)
483 		dev_info(priv->dev, "switching to Host Mode\n");
484 	else
485 		dev_info(priv->dev, "switching to Device Mode\n");
486 
487 	if (priv->vbus) {
488 		if (mode == PHY_MODE_USB_DEVICE)
489 			ret = regulator_disable(priv->vbus);
490 		else
491 			ret = regulator_enable(priv->vbus);
492 		if (ret)
493 			return ret;
494 	}
495 
496 	priv->otg_phy_mode = mode;
497 
498 	ret = priv->drvdata->set_phy_mode(priv, USB2_OTG_PHY, mode);
499 	if (ret)
500 		return ret;
501 
502 	dwc3_meson_g12a_usb_otg_apply_mode(priv, mode);
503 
504 	return 0;
505 }
506 
507 static int dwc3_meson_g12a_role_set(struct usb_role_switch *sw,
508 				    enum usb_role role)
509 {
510 	struct dwc3_meson_g12a *priv = usb_role_switch_get_drvdata(sw);
511 	enum phy_mode mode;
512 
513 	if (role == USB_ROLE_NONE)
514 		return 0;
515 
516 	mode = (role == USB_ROLE_HOST) ? PHY_MODE_USB_HOST
517 				       : PHY_MODE_USB_DEVICE;
518 
519 	if (mode == priv->otg_phy_mode)
520 		return 0;
521 
522 	if (priv->drvdata->otg_phy_host_port_disable)
523 		dev_warn_once(priv->dev, "Manual OTG switch is broken on this "\
524 					 "SoC, when manual switching from "\
525 					 "Host to device, DWC3 controller "\
526 					 "will need to be resetted in order "\
527 					 "to recover usage of the Host port");
528 
529 	return dwc3_meson_g12a_otg_mode_set(priv, mode);
530 }
531 
532 static enum usb_role dwc3_meson_g12a_role_get(struct usb_role_switch *sw)
533 {
534 	struct dwc3_meson_g12a *priv = usb_role_switch_get_drvdata(sw);
535 
536 	return priv->otg_phy_mode == PHY_MODE_USB_HOST ?
537 		USB_ROLE_HOST : USB_ROLE_DEVICE;
538 }
539 
540 static irqreturn_t dwc3_meson_g12a_irq_thread(int irq, void *data)
541 {
542 	struct dwc3_meson_g12a *priv = data;
543 	enum phy_mode otg_id;
544 
545 	otg_id = dwc3_meson_g12a_get_id(priv);
546 	if (otg_id != priv->otg_phy_mode) {
547 		if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
548 			dev_warn(priv->dev, "Failed to switch OTG mode\n");
549 	}
550 
551 	regmap_update_bits(priv->usb_glue_regmap, USB_R5,
552 			   USB_R5_ID_DIG_IRQ, 0);
553 
554 	return IRQ_HANDLED;
555 }
556 
557 static struct device *dwc3_meson_g12_find_child(struct device *dev,
558 						const char *compatible)
559 {
560 	struct platform_device *pdev;
561 	struct device_node *np;
562 
563 	np = of_get_compatible_child(dev->of_node, compatible);
564 	if (!np)
565 		return NULL;
566 
567 	pdev = of_find_device_by_node(np);
568 	of_node_put(np);
569 	if (!pdev)
570 		return NULL;
571 
572 	return &pdev->dev;
573 }
574 
575 static int dwc3_meson_g12a_otg_init(struct platform_device *pdev,
576 				    struct dwc3_meson_g12a *priv)
577 {
578 	enum phy_mode otg_id;
579 	int ret, irq;
580 	struct device *dev = &pdev->dev;
581 
582 	if (!priv->drvdata->otg_switch_supported)
583 		return 0;
584 
585 	if (priv->otg_mode == USB_DR_MODE_OTG) {
586 		/* Ack irq before registering */
587 		regmap_update_bits(priv->usb_glue_regmap, USB_R5,
588 				   USB_R5_ID_DIG_IRQ, 0);
589 
590 		irq = platform_get_irq(pdev, 0);
591 		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
592 						dwc3_meson_g12a_irq_thread,
593 						IRQF_ONESHOT, pdev->name, priv);
594 		if (ret)
595 			return ret;
596 	}
597 
598 	/* Setup OTG mode corresponding to the ID pin */
599 	if (priv->otg_mode == USB_DR_MODE_OTG) {
600 		otg_id = dwc3_meson_g12a_get_id(priv);
601 		if (otg_id != priv->otg_phy_mode) {
602 			if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
603 				dev_warn(dev, "Failed to switch OTG mode\n");
604 		}
605 	}
606 
607 	/* Setup role switcher */
608 	priv->switch_desc.usb2_port = dwc3_meson_g12_find_child(dev,
609 								"snps,dwc3");
610 	priv->switch_desc.udc = dwc3_meson_g12_find_child(dev, "snps,dwc2");
611 	priv->switch_desc.allow_userspace_control = true;
612 	priv->switch_desc.set = dwc3_meson_g12a_role_set;
613 	priv->switch_desc.get = dwc3_meson_g12a_role_get;
614 	priv->switch_desc.driver_data = priv;
615 
616 	priv->role_switch = usb_role_switch_register(dev, &priv->switch_desc);
617 	if (IS_ERR(priv->role_switch))
618 		dev_warn(dev, "Unable to register Role Switch\n");
619 
620 	return 0;
621 }
622 
623 static int dwc3_meson_gxl_setup_regmaps(struct dwc3_meson_g12a *priv,
624 					void __iomem *base)
625 {
626 	/* GXL controls the PHY mode in the PHY registers unlike G12A */
627 	priv->usb_glue_regmap = devm_regmap_init_mmio(priv->dev, base,
628 					&phy_meson_g12a_usb_glue_regmap_conf);
629 	if (IS_ERR(priv->usb_glue_regmap))
630 		return PTR_ERR(priv->usb_glue_regmap);
631 
632 	return 0;
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->usb2_ports; 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 		u2p_regmap_config.name = devm_kasprintf(priv->dev, GFP_KERNEL,
656 							"u2p-%d", i);
657 		if (!u2p_regmap_config.name)
658 			return -ENOMEM;
659 
660 		priv->u2p_regmap[i] = devm_regmap_init_mmio(priv->dev,
661 						base + (i * U2P_REG_SIZE),
662 						&u2p_regmap_config);
663 		if (IS_ERR(priv->u2p_regmap[i]))
664 			return PTR_ERR(priv->u2p_regmap[i]);
665 	}
666 
667 	return 0;
668 }
669 
670 static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
671 {
672 	return dwc3_meson_g12a_usb_init_glue(priv, priv->otg_phy_mode);
673 }
674 
675 static int dwc3_meson_gxl_usb_init(struct dwc3_meson_g12a *priv)
676 {
677 	return dwc3_meson_g12a_usb_init_glue(priv, PHY_MODE_USB_DEVICE);
678 }
679 
680 static int dwc3_meson_gxl_usb_post_init(struct dwc3_meson_g12a *priv)
681 {
682 	int ret;
683 
684 	ret = priv->drvdata->set_phy_mode(priv, USB2_OTG_PHY,
685 					  priv->otg_phy_mode);
686 	if (ret)
687 		return ret;
688 
689 	dwc3_meson_g12a_usb_otg_apply_mode(priv, priv->otg_phy_mode);
690 
691 	return 0;
692 }
693 
694 static int dwc3_meson_g12a_probe(struct platform_device *pdev)
695 {
696 	struct dwc3_meson_g12a	*priv;
697 	struct device		*dev = &pdev->dev;
698 	struct device_node	*np = dev->of_node;
699 	void __iomem *base;
700 	int ret, i;
701 
702 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
703 	if (!priv)
704 		return -ENOMEM;
705 
706 	base = devm_platform_ioremap_resource(pdev, 0);
707 	if (IS_ERR(base))
708 		return PTR_ERR(base);
709 
710 	priv->drvdata = of_device_get_match_data(&pdev->dev);
711 	priv->dev = dev;
712 
713 	priv->vbus = devm_regulator_get_optional(dev, "vbus");
714 	if (IS_ERR(priv->vbus)) {
715 		if (PTR_ERR(priv->vbus) == -EPROBE_DEFER)
716 			return PTR_ERR(priv->vbus);
717 		priv->vbus = NULL;
718 	}
719 
720 	ret = devm_clk_bulk_get(dev,
721 				priv->drvdata->num_clks,
722 				priv->drvdata->clks);
723 	if (ret)
724 		return ret;
725 
726 	ret = clk_bulk_prepare_enable(priv->drvdata->num_clks,
727 				      priv->drvdata->clks);
728 	if (ret)
729 		return ret;
730 
731 	platform_set_drvdata(pdev, priv);
732 
733 	priv->reset = devm_reset_control_get_shared(dev, NULL);
734 	if (IS_ERR(priv->reset)) {
735 		ret = PTR_ERR(priv->reset);
736 		dev_err(dev, "failed to get device reset, err=%d\n", ret);
737 		goto err_disable_clks;
738 	}
739 
740 	ret = reset_control_deassert(priv->reset);
741 	if (ret)
742 		goto err_assert_reset;
743 
744 	ret = dwc3_meson_g12a_get_phys(priv);
745 	if (ret)
746 		goto err_assert_reset;
747 
748 	ret = priv->drvdata->setup_regmaps(priv, base);
749 	if (ret)
750 		return ret;
751 
752 	if (priv->vbus) {
753 		ret = regulator_enable(priv->vbus);
754 		if (ret)
755 			goto err_assert_reset;
756 	}
757 
758 	/* Get dr_mode */
759 	priv->otg_mode = usb_get_dr_mode(dev);
760 
761 	if (priv->otg_mode == USB_DR_MODE_PERIPHERAL)
762 		priv->otg_phy_mode = PHY_MODE_USB_DEVICE;
763 	else
764 		priv->otg_phy_mode = PHY_MODE_USB_HOST;
765 
766 	ret = priv->drvdata->usb_init(priv);
767 	if (ret)
768 		goto err_assert_reset;
769 
770 	/* Init PHYs */
771 	for (i = 0 ; i < PHY_COUNT ; ++i) {
772 		ret = phy_init(priv->phys[i]);
773 		if (ret)
774 			goto err_assert_reset;
775 	}
776 
777 	/* Set PHY Power */
778 	for (i = 0 ; i < PHY_COUNT ; ++i) {
779 		ret = phy_power_on(priv->phys[i]);
780 		if (ret)
781 			goto err_phys_exit;
782 	}
783 
784 	if (priv->drvdata->usb_post_init) {
785 		ret = priv->drvdata->usb_post_init(priv);
786 		if (ret)
787 			goto err_phys_power;
788 	}
789 
790 	ret = of_platform_populate(np, NULL, NULL, dev);
791 	if (ret)
792 		goto err_phys_power;
793 
794 	ret = dwc3_meson_g12a_otg_init(pdev, priv);
795 	if (ret)
796 		goto err_phys_power;
797 
798 	pm_runtime_set_active(dev);
799 	pm_runtime_enable(dev);
800 	pm_runtime_get_sync(dev);
801 
802 	return 0;
803 
804 err_phys_power:
805 	for (i = 0 ; i < PHY_COUNT ; ++i)
806 		phy_power_off(priv->phys[i]);
807 
808 err_phys_exit:
809 	for (i = 0 ; i < PHY_COUNT ; ++i)
810 		phy_exit(priv->phys[i]);
811 
812 err_assert_reset:
813 	reset_control_assert(priv->reset);
814 
815 err_disable_clks:
816 	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
817 				   priv->drvdata->clks);
818 
819 	return ret;
820 }
821 
822 static int dwc3_meson_g12a_remove(struct platform_device *pdev)
823 {
824 	struct dwc3_meson_g12a *priv = platform_get_drvdata(pdev);
825 	struct device *dev = &pdev->dev;
826 	int i;
827 
828 	if (priv->drvdata->otg_switch_supported)
829 		usb_role_switch_unregister(priv->role_switch);
830 
831 	of_platform_depopulate(dev);
832 
833 	for (i = 0 ; i < PHY_COUNT ; ++i) {
834 		phy_power_off(priv->phys[i]);
835 		phy_exit(priv->phys[i]);
836 	}
837 
838 	pm_runtime_disable(dev);
839 	pm_runtime_put_noidle(dev);
840 	pm_runtime_set_suspended(dev);
841 
842 	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
843 				   priv->drvdata->clks);
844 
845 	return 0;
846 }
847 
848 static int __maybe_unused dwc3_meson_g12a_runtime_suspend(struct device *dev)
849 {
850 	struct dwc3_meson_g12a	*priv = dev_get_drvdata(dev);
851 
852 	clk_bulk_disable_unprepare(priv->drvdata->num_clks,
853 				   priv->drvdata->clks);
854 
855 	return 0;
856 }
857 
858 static int __maybe_unused dwc3_meson_g12a_runtime_resume(struct device *dev)
859 {
860 	struct dwc3_meson_g12a	*priv = dev_get_drvdata(dev);
861 
862 	return clk_bulk_prepare_enable(priv->drvdata->num_clks,
863 				       priv->drvdata->clks);
864 }
865 
866 static int __maybe_unused dwc3_meson_g12a_suspend(struct device *dev)
867 {
868 	struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
869 	int i, ret;
870 
871 	if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
872 		ret = regulator_disable(priv->vbus);
873 		if (ret)
874 			return ret;
875 	}
876 
877 	for (i = 0 ; i < PHY_COUNT ; ++i) {
878 		phy_power_off(priv->phys[i]);
879 		phy_exit(priv->phys[i]);
880 	}
881 
882 	reset_control_assert(priv->reset);
883 
884 	return 0;
885 }
886 
887 static int __maybe_unused dwc3_meson_g12a_resume(struct device *dev)
888 {
889 	struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
890 	int i, ret;
891 
892 	reset_control_deassert(priv->reset);
893 
894 	ret = priv->drvdata->usb_init(priv);
895 	if (ret)
896 		return ret;
897 
898 	/* Init PHYs */
899 	for (i = 0 ; i < PHY_COUNT ; ++i) {
900 		ret = phy_init(priv->phys[i]);
901 		if (ret)
902 			return ret;
903 	}
904 
905 	/* Set PHY Power */
906 	for (i = 0 ; i < PHY_COUNT ; ++i) {
907 		ret = phy_power_on(priv->phys[i]);
908 		if (ret)
909 			return ret;
910 	}
911 
912        if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
913                ret = regulator_enable(priv->vbus);
914 		if (ret)
915 			return ret;
916 	}
917 
918 	return 0;
919 }
920 
921 static const struct dev_pm_ops dwc3_meson_g12a_dev_pm_ops = {
922 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_meson_g12a_suspend, dwc3_meson_g12a_resume)
923 	SET_RUNTIME_PM_OPS(dwc3_meson_g12a_runtime_suspend,
924 			   dwc3_meson_g12a_runtime_resume, NULL)
925 };
926 
927 static const struct of_device_id dwc3_meson_g12a_match[] = {
928 	{
929 		.compatible = "amlogic,meson-gxl-usb-ctrl",
930 		.data = &gxl_drvdata,
931 	},
932 	{
933 		.compatible = "amlogic,meson-gxm-usb-ctrl",
934 		.data = &gxm_drvdata,
935 	},
936 	{
937 		.compatible = "amlogic,meson-g12a-usb-ctrl",
938 		.data = &g12a_drvdata,
939 	},
940 	{
941 		.compatible = "amlogic,meson-a1-usb-ctrl",
942 		.data = &a1_drvdata,
943 	},
944 	{ /* Sentinel */ }
945 };
946 MODULE_DEVICE_TABLE(of, dwc3_meson_g12a_match);
947 
948 static struct platform_driver dwc3_meson_g12a_driver = {
949 	.probe		= dwc3_meson_g12a_probe,
950 	.remove		= dwc3_meson_g12a_remove,
951 	.driver		= {
952 		.name	= "dwc3-meson-g12a",
953 		.of_match_table = dwc3_meson_g12a_match,
954 		.pm	= &dwc3_meson_g12a_dev_pm_ops,
955 	},
956 };
957 
958 module_platform_driver(dwc3_meson_g12a_driver);
959 MODULE_LICENSE("GPL v2");
960 MODULE_DESCRIPTION("Amlogic Meson G12A USB Glue Layer");
961 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
962