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 struct eusb2_repeater_init_tbl_reg {
41 unsigned int reg;
42 unsigned int value;
43 };
44
45 struct eusb2_repeater_cfg {
46 const struct eusb2_repeater_init_tbl_reg *init_tbl;
47 int init_tbl_num;
48 const char * const *vreg_list;
49 int num_vregs;
50 };
51
52 struct eusb2_repeater {
53 struct device *dev;
54 struct regmap *regmap;
55 struct phy *phy;
56 struct regulator_bulk_data *vregs;
57 const struct eusb2_repeater_cfg *cfg;
58 u32 base;
59 enum phy_mode mode;
60 };
61
62 static const char * const pm8550b_vreg_l[] = {
63 "vdd18", "vdd3",
64 };
65
66 static const struct eusb2_repeater_init_tbl_reg pm8550b_init_tbl[] = {
67 { EUSB2_TUNE_IUSB2, 0x8 },
68 { EUSB2_TUNE_SQUELCH_U, 0x3 },
69 { EUSB2_TUNE_USB2_PREEM, 0x5 },
70 };
71
72 static const struct eusb2_repeater_init_tbl_reg smb2360_init_tbl[] = {
73 { EUSB2_TUNE_IUSB2, 0x5 },
74 { EUSB2_TUNE_SQUELCH_U, 0x3 },
75 { EUSB2_TUNE_USB2_PREEM, 0x2 },
76 };
77
78 static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
79 .init_tbl = pm8550b_init_tbl,
80 .init_tbl_num = ARRAY_SIZE(pm8550b_init_tbl),
81 .vreg_list = pm8550b_vreg_l,
82 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
83 };
84
85 static const struct eusb2_repeater_cfg smb2360_eusb2_cfg = {
86 .init_tbl = smb2360_init_tbl,
87 .init_tbl_num = ARRAY_SIZE(smb2360_init_tbl),
88 .vreg_list = pm8550b_vreg_l,
89 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
90 };
91
eusb2_repeater_init_vregs(struct eusb2_repeater * rptr)92 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
93 {
94 int num = rptr->cfg->num_vregs;
95 struct device *dev = rptr->dev;
96 int i;
97
98 rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
99 if (!rptr->vregs)
100 return -ENOMEM;
101
102 for (i = 0; i < num; i++)
103 rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
104
105 return devm_regulator_bulk_get(dev, num, rptr->vregs);
106 }
107
eusb2_repeater_init(struct phy * phy)108 static int eusb2_repeater_init(struct phy *phy)
109 {
110 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
111 struct device_node *np = rptr->dev->of_node;
112 struct regmap *regmap = rptr->regmap;
113 u32 base = rptr->base;
114 u32 poll_val;
115 int ret;
116 u8 val;
117
118 ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
119 if (ret)
120 return ret;
121
122 regmap_write(regmap, base + EUSB2_EN_CTL1, EUSB2_RPTR_EN);
123
124 /* Write registers from init table */
125 for (int i = 0; i < rptr->cfg->init_tbl_num; i++)
126 regmap_write(regmap, base + rptr->cfg->init_tbl[i].reg,
127 rptr->cfg->init_tbl[i].value);
128
129 /* Override registers from devicetree values */
130 if (!of_property_read_u8(np, "qcom,tune-usb2-amplitude", &val))
131 regmap_write(regmap, base + EUSB2_TUNE_USB2_PREEM, val);
132
133 if (!of_property_read_u8(np, "qcom,tune-usb2-disc-thres", &val))
134 regmap_write(regmap, base + EUSB2_TUNE_HSDISC, val);
135
136 if (!of_property_read_u8(np, "qcom,tune-usb2-preem", &val))
137 regmap_write(regmap, base + EUSB2_TUNE_IUSB2, val);
138
139 /* Wait for status OK */
140 ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, poll_val,
141 poll_val & RPTR_OK, 10, 5);
142 if (ret)
143 dev_err(rptr->dev, "initialization timed-out\n");
144
145 return ret;
146 }
147
eusb2_repeater_set_mode(struct phy * phy,enum phy_mode mode,int submode)148 static int eusb2_repeater_set_mode(struct phy *phy,
149 enum phy_mode mode, int submode)
150 {
151 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
152 struct regmap *regmap = rptr->regmap;
153 u32 base = rptr->base;
154
155 switch (mode) {
156 case PHY_MODE_USB_HOST:
157 /*
158 * CM.Lx is prohibited when repeater is already into Lx state as
159 * per eUSB 1.2 Spec. Below implement software workaround until
160 * PHY and controller is fixing seen observation.
161 */
162 regmap_write(regmap, base + EUSB2_FORCE_EN_5, F_CLK_19P2M_EN);
163 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, V_CLK_19P2M_EN);
164 break;
165 case PHY_MODE_USB_DEVICE:
166 /*
167 * In device mode clear host mode related workaround as there
168 * is no repeater reset available, and enable/disable of
169 * repeater doesn't clear previous value due to shared
170 * regulators (say host <-> device mode switch).
171 */
172 regmap_write(regmap, base + EUSB2_FORCE_EN_5, 0);
173 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, 0);
174 break;
175 default:
176 return -EINVAL;
177 }
178
179 return 0;
180 }
181
eusb2_repeater_exit(struct phy * phy)182 static int eusb2_repeater_exit(struct phy *phy)
183 {
184 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
185
186 return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
187 }
188
189 static const struct phy_ops eusb2_repeater_ops = {
190 .init = eusb2_repeater_init,
191 .exit = eusb2_repeater_exit,
192 .set_mode = eusb2_repeater_set_mode,
193 .owner = THIS_MODULE,
194 };
195
eusb2_repeater_probe(struct platform_device * pdev)196 static int eusb2_repeater_probe(struct platform_device *pdev)
197 {
198 struct eusb2_repeater *rptr;
199 struct device *dev = &pdev->dev;
200 struct phy_provider *phy_provider;
201 struct device_node *np = dev->of_node;
202 u32 res;
203 int ret;
204
205 rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
206 if (!rptr)
207 return -ENOMEM;
208
209 rptr->dev = dev;
210 dev_set_drvdata(dev, rptr);
211
212 rptr->cfg = of_device_get_match_data(dev);
213 if (!rptr->cfg)
214 return -EINVAL;
215
216 rptr->regmap = dev_get_regmap(dev->parent, NULL);
217 if (!rptr->regmap)
218 return -ENODEV;
219
220 ret = of_property_read_u32(np, "reg", &res);
221 if (ret < 0)
222 return ret;
223
224 rptr->base = res;
225
226 ret = eusb2_repeater_init_vregs(rptr);
227 if (ret < 0) {
228 dev_err(dev, "unable to get supplies\n");
229 return ret;
230 }
231
232 rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
233 if (IS_ERR(rptr->phy)) {
234 dev_err(dev, "failed to create PHY: %d\n", ret);
235 return PTR_ERR(rptr->phy);
236 }
237
238 phy_set_drvdata(rptr->phy, rptr);
239
240 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
241 if (IS_ERR(phy_provider))
242 return PTR_ERR(phy_provider);
243
244 return 0;
245 }
246
eusb2_repeater_remove(struct platform_device * pdev)247 static void eusb2_repeater_remove(struct platform_device *pdev)
248 {
249 struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
250
251 if (!rptr)
252 return;
253
254 eusb2_repeater_exit(rptr->phy);
255 }
256
257 static const struct of_device_id eusb2_repeater_of_match_table[] = {
258 {
259 .compatible = "qcom,pm8550b-eusb2-repeater",
260 .data = &pm8550b_eusb2_cfg,
261 },
262 {
263 .compatible = "qcom,smb2360-eusb2-repeater",
264 .data = &smb2360_eusb2_cfg,
265 },
266 { },
267 };
268 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
269
270 static struct platform_driver eusb2_repeater_driver = {
271 .probe = eusb2_repeater_probe,
272 .remove = eusb2_repeater_remove,
273 .driver = {
274 .name = "qcom-eusb2-repeater",
275 .of_match_table = eusb2_repeater_of_match_table,
276 },
277 };
278
279 module_platform_driver(eusb2_repeater_driver);
280
281 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
282 MODULE_LICENSE("GPL");
283