xref: /linux/drivers/phy/qualcomm/phy-qcom-eusb2-repeater.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2023, Linaro Limited
4  */
5 
6 #include <linux/module.h>
7 #include <linux/platform_device.h>
8 #include <linux/regulator/consumer.h>
9 #include <linux/regmap.h>
10 #include <linux/of.h>
11 #include <linux/phy/phy.h>
12 
13 /* eUSB2 status registers */
14 #define EUSB2_RPTR_STATUS		0x08
15 #define	RPTR_OK				BIT(7)
16 
17 /* eUSB2 control registers */
18 #define EUSB2_EN_CTL1			0x46
19 #define EUSB2_RPTR_EN			BIT(7)
20 
21 #define EUSB2_FORCE_EN_5		0xe8
22 #define F_CLK_19P2M_EN			BIT(6)
23 
24 #define EUSB2_FORCE_VAL_5		0xeD
25 #define V_CLK_19P2M_EN			BIT(6)
26 
27 #define EUSB2_TUNE_USB2_CROSSOVER	0x50
28 #define EUSB2_TUNE_IUSB2		0x51
29 #define EUSB2_TUNE_RES_FSDIF		0x52
30 #define EUSB2_TUNE_HSDISC		0x53
31 #define EUSB2_TUNE_SQUELCH_U		0x54
32 #define EUSB2_TUNE_USB2_SLEW		0x55
33 #define EUSB2_TUNE_USB2_EQU		0x56
34 #define EUSB2_TUNE_USB2_PREEM		0x57
35 #define EUSB2_TUNE_USB2_HS_COMP_CUR	0x58
36 #define EUSB2_TUNE_EUSB_SLEW		0x59
37 #define EUSB2_TUNE_EUSB_EQU		0x5A
38 #define EUSB2_TUNE_EUSB_HS_COMP_CUR	0x5B
39 
40 enum eusb2_reg_layout {
41 	TUNE_EUSB_HS_COMP_CUR,
42 	TUNE_EUSB_EQU,
43 	TUNE_EUSB_SLEW,
44 	TUNE_USB2_HS_COMP_CUR,
45 	TUNE_USB2_PREEM,
46 	TUNE_USB2_EQU,
47 	TUNE_USB2_SLEW,
48 	TUNE_SQUELCH_U,
49 	TUNE_HSDISC,
50 	TUNE_RES_FSDIF,
51 	TUNE_IUSB2,
52 	TUNE_USB2_CROSSOVER,
53 	NUM_TUNE_FIELDS,
54 
55 	FORCE_VAL_5 = NUM_TUNE_FIELDS,
56 	FORCE_EN_5,
57 
58 	EN_CTL1,
59 
60 	RPTR_STATUS,
61 	LAYOUT_SIZE,
62 };
63 
64 struct eusb2_repeater_cfg {
65 	const u32 *init_tbl;
66 	int init_tbl_num;
67 	const char * const *vreg_list;
68 	int num_vregs;
69 };
70 
71 struct eusb2_repeater {
72 	struct device *dev;
73 	struct regmap *regmap;
74 	struct phy *phy;
75 	struct regulator_bulk_data *vregs;
76 	const struct eusb2_repeater_cfg *cfg;
77 	u32 base;
78 	enum phy_mode mode;
79 };
80 
81 static const char * const pm8550b_vreg_l[] = {
82 	"vdd18", "vdd3",
83 };
84 
85 static const u32 pm8550b_init_tbl[NUM_TUNE_FIELDS] = {
86 	[TUNE_IUSB2] = 0x8,
87 	[TUNE_SQUELCH_U] = 0x3,
88 	[TUNE_USB2_PREEM] = 0x5,
89 };
90 
91 static const u32 smb2360_init_tbl[NUM_TUNE_FIELDS] = {
92 	[TUNE_IUSB2] = 0x5,
93 	[TUNE_SQUELCH_U] = 0x3,
94 	[TUNE_USB2_PREEM] = 0x2,
95 };
96 
97 static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
98 	.init_tbl	= pm8550b_init_tbl,
99 	.init_tbl_num	= ARRAY_SIZE(pm8550b_init_tbl),
100 	.vreg_list	= pm8550b_vreg_l,
101 	.num_vregs	= ARRAY_SIZE(pm8550b_vreg_l),
102 };
103 
104 static const struct eusb2_repeater_cfg smb2360_eusb2_cfg = {
105 	.init_tbl	= smb2360_init_tbl,
106 	.init_tbl_num	= ARRAY_SIZE(smb2360_init_tbl),
107 	.vreg_list	= pm8550b_vreg_l,
108 	.num_vregs	= ARRAY_SIZE(pm8550b_vreg_l),
109 };
110 
111 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
112 {
113 	int num = rptr->cfg->num_vregs;
114 	struct device *dev = rptr->dev;
115 	int i;
116 
117 	rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
118 	if (!rptr->vregs)
119 		return -ENOMEM;
120 
121 	for (i = 0; i < num; i++)
122 		rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
123 
124 	return devm_regulator_bulk_get(dev, num, rptr->vregs);
125 }
126 
127 static int eusb2_repeater_init(struct phy *phy)
128 {
129 	struct eusb2_repeater *rptr = phy_get_drvdata(phy);
130 	struct device_node *np = rptr->dev->of_node;
131 	struct regmap *regmap = rptr->regmap;
132 	const u32 *init_tbl = rptr->cfg->init_tbl;
133 	u8 tune_usb2_preem = init_tbl[TUNE_USB2_PREEM];
134 	u8 tune_hsdisc = init_tbl[TUNE_HSDISC];
135 	u8 tune_iusb2 = init_tbl[TUNE_IUSB2];
136 	u32 base = rptr->base;
137 	u32 val;
138 	int ret;
139 
140 	of_property_read_u8(np, "qcom,tune-usb2-amplitude", &tune_iusb2);
141 	of_property_read_u8(np, "qcom,tune-usb2-disc-thres", &tune_hsdisc);
142 	of_property_read_u8(np, "qcom,tune-usb2-preem", &tune_usb2_preem);
143 
144 	ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
145 	if (ret)
146 		return ret;
147 
148 	regmap_write(regmap, base + EUSB2_EN_CTL1, EUSB2_RPTR_EN);
149 
150 	regmap_write(regmap, base + EUSB2_TUNE_EUSB_HS_COMP_CUR, init_tbl[TUNE_EUSB_HS_COMP_CUR]);
151 	regmap_write(regmap, base + EUSB2_TUNE_EUSB_EQU, init_tbl[TUNE_EUSB_EQU]);
152 	regmap_write(regmap, base + EUSB2_TUNE_EUSB_SLEW, init_tbl[TUNE_EUSB_SLEW]);
153 	regmap_write(regmap, base + EUSB2_TUNE_USB2_HS_COMP_CUR, init_tbl[TUNE_USB2_HS_COMP_CUR]);
154 	regmap_write(regmap, base + EUSB2_TUNE_USB2_EQU, init_tbl[TUNE_USB2_EQU]);
155 	regmap_write(regmap, base + EUSB2_TUNE_USB2_SLEW, init_tbl[TUNE_USB2_SLEW]);
156 	regmap_write(regmap, base + EUSB2_TUNE_SQUELCH_U, init_tbl[TUNE_SQUELCH_U]);
157 	regmap_write(regmap, base + EUSB2_TUNE_RES_FSDIF, init_tbl[TUNE_RES_FSDIF]);
158 	regmap_write(regmap, base + EUSB2_TUNE_USB2_CROSSOVER, init_tbl[TUNE_USB2_CROSSOVER]);
159 
160 	regmap_write(regmap, base + EUSB2_TUNE_USB2_PREEM, tune_usb2_preem);
161 	regmap_write(regmap, base + EUSB2_TUNE_HSDISC, tune_hsdisc);
162 	regmap_write(regmap, base + EUSB2_TUNE_IUSB2, tune_iusb2);
163 
164 	ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, val, val & RPTR_OK, 10, 5);
165 	if (ret)
166 		dev_err(rptr->dev, "initialization timed-out\n");
167 
168 	return ret;
169 }
170 
171 static int eusb2_repeater_set_mode(struct phy *phy,
172 				   enum phy_mode mode, int submode)
173 {
174 	struct eusb2_repeater *rptr = phy_get_drvdata(phy);
175 	struct regmap *regmap = rptr->regmap;
176 	u32 base = rptr->base;
177 
178 	switch (mode) {
179 	case PHY_MODE_USB_HOST:
180 		/*
181 		 * CM.Lx is prohibited when repeater is already into Lx state as
182 		 * per eUSB 1.2 Spec. Below implement software workaround until
183 		 * PHY and controller is fixing seen observation.
184 		 */
185 		regmap_write(regmap, base + EUSB2_FORCE_EN_5, F_CLK_19P2M_EN);
186 		regmap_write(regmap, base + EUSB2_FORCE_VAL_5, V_CLK_19P2M_EN);
187 		break;
188 	case PHY_MODE_USB_DEVICE:
189 		/*
190 		 * In device mode clear host mode related workaround as there
191 		 * is no repeater reset available, and enable/disable of
192 		 * repeater doesn't clear previous value due to shared
193 		 * regulators (say host <-> device mode switch).
194 		 */
195 		regmap_write(regmap, base + EUSB2_FORCE_EN_5, 0);
196 		regmap_write(regmap, base + EUSB2_FORCE_VAL_5, 0);
197 		break;
198 	default:
199 		return -EINVAL;
200 	}
201 
202 	return 0;
203 }
204 
205 static int eusb2_repeater_exit(struct phy *phy)
206 {
207 	struct eusb2_repeater *rptr = phy_get_drvdata(phy);
208 
209 	return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
210 }
211 
212 static const struct phy_ops eusb2_repeater_ops = {
213 	.init		= eusb2_repeater_init,
214 	.exit		= eusb2_repeater_exit,
215 	.set_mode	= eusb2_repeater_set_mode,
216 	.owner		= THIS_MODULE,
217 };
218 
219 static int eusb2_repeater_probe(struct platform_device *pdev)
220 {
221 	struct eusb2_repeater *rptr;
222 	struct device *dev = &pdev->dev;
223 	struct phy_provider *phy_provider;
224 	struct device_node *np = dev->of_node;
225 	u32 res;
226 	int ret;
227 
228 	rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
229 	if (!rptr)
230 		return -ENOMEM;
231 
232 	rptr->dev = dev;
233 	dev_set_drvdata(dev, rptr);
234 
235 	rptr->cfg = of_device_get_match_data(dev);
236 	if (!rptr->cfg)
237 		return -EINVAL;
238 
239 	rptr->regmap = dev_get_regmap(dev->parent, NULL);
240 	if (!rptr->regmap)
241 		return -ENODEV;
242 
243 	ret = of_property_read_u32(np, "reg", &res);
244 	if (ret < 0)
245 		return ret;
246 
247 	rptr->base = res;
248 
249 	ret = eusb2_repeater_init_vregs(rptr);
250 	if (ret < 0) {
251 		dev_err(dev, "unable to get supplies\n");
252 		return ret;
253 	}
254 
255 	rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
256 	if (IS_ERR(rptr->phy)) {
257 		dev_err(dev, "failed to create PHY: %d\n", ret);
258 		return PTR_ERR(rptr->phy);
259 	}
260 
261 	phy_set_drvdata(rptr->phy, rptr);
262 
263 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
264 	if (IS_ERR(phy_provider))
265 		return PTR_ERR(phy_provider);
266 
267 	dev_info(dev, "Registered Qcom-eUSB2 repeater\n");
268 
269 	return 0;
270 }
271 
272 static void eusb2_repeater_remove(struct platform_device *pdev)
273 {
274 	struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
275 
276 	if (!rptr)
277 		return;
278 
279 	eusb2_repeater_exit(rptr->phy);
280 }
281 
282 static const struct of_device_id eusb2_repeater_of_match_table[] = {
283 	{
284 		.compatible = "qcom,pm8550b-eusb2-repeater",
285 		.data = &pm8550b_eusb2_cfg,
286 	},
287 	{
288 		.compatible = "qcom,smb2360-eusb2-repeater",
289 		.data = &smb2360_eusb2_cfg,
290 	},
291 	{ },
292 };
293 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
294 
295 static struct platform_driver eusb2_repeater_driver = {
296 	.probe		= eusb2_repeater_probe,
297 	.remove		= eusb2_repeater_remove,
298 	.driver = {
299 		.name	= "qcom-eusb2-repeater",
300 		.of_match_table = eusb2_repeater_of_match_table,
301 	},
302 };
303 
304 module_platform_driver(eusb2_repeater_driver);
305 
306 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
307 MODULE_LICENSE("GPL");
308