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 #define QCOM_EUSB2_REPEATER_INIT_CFG(r, v) \
41 { \
42 .reg = r, \
43 .val = v, \
44 }
45
46 enum reg_fields {
47 F_TUNE_EUSB_HS_COMP_CUR,
48 F_TUNE_EUSB_EQU,
49 F_TUNE_EUSB_SLEW,
50 F_TUNE_USB2_HS_COMP_CUR,
51 F_TUNE_USB2_PREEM,
52 F_TUNE_USB2_EQU,
53 F_TUNE_USB2_SLEW,
54 F_TUNE_SQUELCH_U,
55 F_TUNE_HSDISC,
56 F_TUNE_RES_FSDIF,
57 F_TUNE_IUSB2,
58 F_TUNE_USB2_CROSSOVER,
59 F_NUM_TUNE_FIELDS,
60
61 F_FORCE_VAL_5 = F_NUM_TUNE_FIELDS,
62 F_FORCE_EN_5,
63
64 F_EN_CTL1,
65
66 F_RPTR_STATUS,
67 F_NUM_FIELDS,
68 };
69
70 static struct reg_field eusb2_repeater_tune_reg_fields[F_NUM_FIELDS] = {
71 [F_TUNE_EUSB_HS_COMP_CUR] = REG_FIELD(EUSB2_TUNE_EUSB_HS_COMP_CUR, 0, 1),
72 [F_TUNE_EUSB_EQU] = REG_FIELD(EUSB2_TUNE_EUSB_EQU, 0, 1),
73 [F_TUNE_EUSB_SLEW] = REG_FIELD(EUSB2_TUNE_EUSB_SLEW, 0, 1),
74 [F_TUNE_USB2_HS_COMP_CUR] = REG_FIELD(EUSB2_TUNE_USB2_HS_COMP_CUR, 0, 1),
75 [F_TUNE_USB2_PREEM] = REG_FIELD(EUSB2_TUNE_USB2_PREEM, 0, 2),
76 [F_TUNE_USB2_EQU] = REG_FIELD(EUSB2_TUNE_USB2_EQU, 0, 1),
77 [F_TUNE_USB2_SLEW] = REG_FIELD(EUSB2_TUNE_USB2_SLEW, 0, 1),
78 [F_TUNE_SQUELCH_U] = REG_FIELD(EUSB2_TUNE_SQUELCH_U, 0, 2),
79 [F_TUNE_HSDISC] = REG_FIELD(EUSB2_TUNE_HSDISC, 0, 2),
80 [F_TUNE_RES_FSDIF] = REG_FIELD(EUSB2_TUNE_RES_FSDIF, 0, 2),
81 [F_TUNE_IUSB2] = REG_FIELD(EUSB2_TUNE_IUSB2, 0, 3),
82 [F_TUNE_USB2_CROSSOVER] = REG_FIELD(EUSB2_TUNE_USB2_CROSSOVER, 0, 2),
83
84 [F_FORCE_VAL_5] = REG_FIELD(EUSB2_FORCE_VAL_5, 0, 7),
85 [F_FORCE_EN_5] = REG_FIELD(EUSB2_FORCE_EN_5, 0, 7),
86
87 [F_EN_CTL1] = REG_FIELD(EUSB2_EN_CTL1, 0, 7),
88
89 [F_RPTR_STATUS] = REG_FIELD(EUSB2_RPTR_STATUS, 0, 7),
90 };
91
92 struct eusb2_repeater_cfg {
93 const u32 *init_tbl;
94 int init_tbl_num;
95 const char * const *vreg_list;
96 int num_vregs;
97 };
98
99 struct eusb2_repeater {
100 struct device *dev;
101 struct regmap_field *regs[F_NUM_FIELDS];
102 struct phy *phy;
103 struct regulator_bulk_data *vregs;
104 const struct eusb2_repeater_cfg *cfg;
105 enum phy_mode mode;
106 };
107
108 static const char * const pm8550b_vreg_l[] = {
109 "vdd18", "vdd3",
110 };
111
112 static const u32 pm8550b_init_tbl[F_NUM_TUNE_FIELDS] = {
113 [F_TUNE_IUSB2] = 0x8,
114 [F_TUNE_SQUELCH_U] = 0x3,
115 [F_TUNE_USB2_PREEM] = 0x5,
116 };
117
118 static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
119 .init_tbl = pm8550b_init_tbl,
120 .init_tbl_num = ARRAY_SIZE(pm8550b_init_tbl),
121 .vreg_list = pm8550b_vreg_l,
122 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
123 };
124
eusb2_repeater_init_vregs(struct eusb2_repeater * rptr)125 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
126 {
127 int num = rptr->cfg->num_vregs;
128 struct device *dev = rptr->dev;
129 int i;
130
131 rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
132 if (!rptr->vregs)
133 return -ENOMEM;
134
135 for (i = 0; i < num; i++)
136 rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
137
138 return devm_regulator_bulk_get(dev, num, rptr->vregs);
139 }
140
eusb2_repeater_init(struct phy * phy)141 static int eusb2_repeater_init(struct phy *phy)
142 {
143 struct reg_field *regfields = eusb2_repeater_tune_reg_fields;
144 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
145 const u32 *init_tbl = rptr->cfg->init_tbl;
146 u32 val;
147 int ret;
148 int i;
149
150 ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
151 if (ret)
152 return ret;
153
154 regmap_field_update_bits(rptr->regs[F_EN_CTL1], EUSB2_RPTR_EN, EUSB2_RPTR_EN);
155
156 for (i = 0; i < F_NUM_TUNE_FIELDS; i++) {
157 if (init_tbl[i]) {
158 regmap_field_update_bits(rptr->regs[i], init_tbl[i], init_tbl[i]);
159 } else {
160 /* Write 0 if there's no value set */
161 u32 mask = GENMASK(regfields[i].msb, regfields[i].lsb);
162
163 regmap_field_update_bits(rptr->regs[i], mask, 0);
164 }
165 }
166
167 ret = regmap_field_read_poll_timeout(rptr->regs[F_RPTR_STATUS],
168 val, val & RPTR_OK, 10, 5);
169 if (ret)
170 dev_err(rptr->dev, "initialization timed-out\n");
171
172 return ret;
173 }
174
eusb2_repeater_set_mode(struct phy * phy,enum phy_mode mode,int submode)175 static int eusb2_repeater_set_mode(struct phy *phy,
176 enum phy_mode mode, int submode)
177 {
178 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
179
180 switch (mode) {
181 case PHY_MODE_USB_HOST:
182 /*
183 * CM.Lx is prohibited when repeater is already into Lx state as
184 * per eUSB 1.2 Spec. Below implement software workaround until
185 * PHY and controller is fixing seen observation.
186 */
187 regmap_field_update_bits(rptr->regs[F_FORCE_EN_5],
188 F_CLK_19P2M_EN, F_CLK_19P2M_EN);
189 regmap_field_update_bits(rptr->regs[F_FORCE_VAL_5],
190 V_CLK_19P2M_EN, V_CLK_19P2M_EN);
191 break;
192 case PHY_MODE_USB_DEVICE:
193 /*
194 * In device mode clear host mode related workaround as there
195 * is no repeater reset available, and enable/disable of
196 * repeater doesn't clear previous value due to shared
197 * regulators (say host <-> device mode switch).
198 */
199 regmap_field_update_bits(rptr->regs[F_FORCE_EN_5],
200 F_CLK_19P2M_EN, 0);
201 regmap_field_update_bits(rptr->regs[F_FORCE_VAL_5],
202 V_CLK_19P2M_EN, 0);
203 break;
204 default:
205 return -EINVAL;
206 }
207
208 return 0;
209 }
210
eusb2_repeater_exit(struct phy * phy)211 static int eusb2_repeater_exit(struct phy *phy)
212 {
213 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
214
215 return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
216 }
217
218 static const struct phy_ops eusb2_repeater_ops = {
219 .init = eusb2_repeater_init,
220 .exit = eusb2_repeater_exit,
221 .set_mode = eusb2_repeater_set_mode,
222 .owner = THIS_MODULE,
223 };
224
eusb2_repeater_probe(struct platform_device * pdev)225 static int eusb2_repeater_probe(struct platform_device *pdev)
226 {
227 struct eusb2_repeater *rptr;
228 struct device *dev = &pdev->dev;
229 struct phy_provider *phy_provider;
230 struct device_node *np = dev->of_node;
231 struct regmap *regmap;
232 int i, ret;
233 u32 res;
234
235 rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
236 if (!rptr)
237 return -ENOMEM;
238
239 rptr->dev = dev;
240 dev_set_drvdata(dev, rptr);
241
242 rptr->cfg = of_device_get_match_data(dev);
243 if (!rptr->cfg)
244 return -EINVAL;
245
246 regmap = dev_get_regmap(dev->parent, NULL);
247 if (!regmap)
248 return -ENODEV;
249
250 ret = of_property_read_u32(np, "reg", &res);
251 if (ret < 0)
252 return ret;
253
254 for (i = 0; i < F_NUM_FIELDS; i++)
255 eusb2_repeater_tune_reg_fields[i].reg += res;
256
257 ret = devm_regmap_field_bulk_alloc(dev, regmap, rptr->regs,
258 eusb2_repeater_tune_reg_fields,
259 F_NUM_FIELDS);
260 if (ret)
261 return ret;
262
263 ret = eusb2_repeater_init_vregs(rptr);
264 if (ret < 0) {
265 dev_err(dev, "unable to get supplies\n");
266 return ret;
267 }
268
269 rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
270 if (IS_ERR(rptr->phy)) {
271 dev_err(dev, "failed to create PHY: %d\n", ret);
272 return PTR_ERR(rptr->phy);
273 }
274
275 phy_set_drvdata(rptr->phy, rptr);
276
277 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
278 if (IS_ERR(phy_provider))
279 return PTR_ERR(phy_provider);
280
281 dev_info(dev, "Registered Qcom-eUSB2 repeater\n");
282
283 return 0;
284 }
285
eusb2_repeater_remove(struct platform_device * pdev)286 static void eusb2_repeater_remove(struct platform_device *pdev)
287 {
288 struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
289
290 if (!rptr)
291 return;
292
293 eusb2_repeater_exit(rptr->phy);
294 }
295
296 static const struct of_device_id eusb2_repeater_of_match_table[] = {
297 {
298 .compatible = "qcom,pm8550b-eusb2-repeater",
299 .data = &pm8550b_eusb2_cfg,
300 },
301 { },
302 };
303 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
304
305 static struct platform_driver eusb2_repeater_driver = {
306 .probe = eusb2_repeater_probe,
307 .remove_new = eusb2_repeater_remove,
308 .driver = {
309 .name = "qcom-eusb2-repeater",
310 .of_match_table = eusb2_repeater_of_match_table,
311 },
312 };
313
314 module_platform_driver(eusb2_repeater_driver);
315
316 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
317 MODULE_LICENSE("GPL");
318