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 struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
92 .init_tbl = pm8550b_init_tbl,
93 .init_tbl_num = ARRAY_SIZE(pm8550b_init_tbl),
94 .vreg_list = pm8550b_vreg_l,
95 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
96 };
97
eusb2_repeater_init_vregs(struct eusb2_repeater * rptr)98 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
99 {
100 int num = rptr->cfg->num_vregs;
101 struct device *dev = rptr->dev;
102 int i;
103
104 rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
105 if (!rptr->vregs)
106 return -ENOMEM;
107
108 for (i = 0; i < num; i++)
109 rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
110
111 return devm_regulator_bulk_get(dev, num, rptr->vregs);
112 }
113
eusb2_repeater_init(struct phy * phy)114 static int eusb2_repeater_init(struct phy *phy)
115 {
116 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
117 struct device_node *np = rptr->dev->of_node;
118 struct regmap *regmap = rptr->regmap;
119 const u32 *init_tbl = rptr->cfg->init_tbl;
120 u8 tune_usb2_preem = init_tbl[TUNE_USB2_PREEM];
121 u8 tune_hsdisc = init_tbl[TUNE_HSDISC];
122 u8 tune_iusb2 = init_tbl[TUNE_IUSB2];
123 u32 base = rptr->base;
124 u32 val;
125 int ret;
126
127 of_property_read_u8(np, "qcom,tune-usb2-amplitude", &tune_iusb2);
128 of_property_read_u8(np, "qcom,tune-usb2-disc-thres", &tune_hsdisc);
129 of_property_read_u8(np, "qcom,tune-usb2-preem", &tune_usb2_preem);
130
131 ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
132 if (ret)
133 return ret;
134
135 regmap_write(regmap, base + EUSB2_EN_CTL1, EUSB2_RPTR_EN);
136
137 regmap_write(regmap, base + EUSB2_TUNE_EUSB_HS_COMP_CUR, init_tbl[TUNE_EUSB_HS_COMP_CUR]);
138 regmap_write(regmap, base + EUSB2_TUNE_EUSB_EQU, init_tbl[TUNE_EUSB_EQU]);
139 regmap_write(regmap, base + EUSB2_TUNE_EUSB_SLEW, init_tbl[TUNE_EUSB_SLEW]);
140 regmap_write(regmap, base + EUSB2_TUNE_USB2_HS_COMP_CUR, init_tbl[TUNE_USB2_HS_COMP_CUR]);
141 regmap_write(regmap, base + EUSB2_TUNE_USB2_EQU, init_tbl[TUNE_USB2_EQU]);
142 regmap_write(regmap, base + EUSB2_TUNE_USB2_SLEW, init_tbl[TUNE_USB2_SLEW]);
143 regmap_write(regmap, base + EUSB2_TUNE_SQUELCH_U, init_tbl[TUNE_SQUELCH_U]);
144 regmap_write(regmap, base + EUSB2_TUNE_RES_FSDIF, init_tbl[TUNE_RES_FSDIF]);
145 regmap_write(regmap, base + EUSB2_TUNE_USB2_CROSSOVER, init_tbl[TUNE_USB2_CROSSOVER]);
146
147 regmap_write(regmap, base + EUSB2_TUNE_USB2_PREEM, tune_usb2_preem);
148 regmap_write(regmap, base + EUSB2_TUNE_HSDISC, tune_hsdisc);
149 regmap_write(regmap, base + EUSB2_TUNE_IUSB2, tune_iusb2);
150
151 ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, val, val & RPTR_OK, 10, 5);
152 if (ret)
153 dev_err(rptr->dev, "initialization timed-out\n");
154
155 return ret;
156 }
157
eusb2_repeater_set_mode(struct phy * phy,enum phy_mode mode,int submode)158 static int eusb2_repeater_set_mode(struct phy *phy,
159 enum phy_mode mode, int submode)
160 {
161 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
162 struct regmap *regmap = rptr->regmap;
163 u32 base = rptr->base;
164
165 switch (mode) {
166 case PHY_MODE_USB_HOST:
167 /*
168 * CM.Lx is prohibited when repeater is already into Lx state as
169 * per eUSB 1.2 Spec. Below implement software workaround until
170 * PHY and controller is fixing seen observation.
171 */
172 regmap_write(regmap, base + EUSB2_FORCE_EN_5, F_CLK_19P2M_EN);
173 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, V_CLK_19P2M_EN);
174 break;
175 case PHY_MODE_USB_DEVICE:
176 /*
177 * In device mode clear host mode related workaround as there
178 * is no repeater reset available, and enable/disable of
179 * repeater doesn't clear previous value due to shared
180 * regulators (say host <-> device mode switch).
181 */
182 regmap_write(regmap, base + EUSB2_FORCE_EN_5, 0);
183 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, 0);
184 break;
185 default:
186 return -EINVAL;
187 }
188
189 return 0;
190 }
191
eusb2_repeater_exit(struct phy * phy)192 static int eusb2_repeater_exit(struct phy *phy)
193 {
194 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
195
196 return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
197 }
198
199 static const struct phy_ops eusb2_repeater_ops = {
200 .init = eusb2_repeater_init,
201 .exit = eusb2_repeater_exit,
202 .set_mode = eusb2_repeater_set_mode,
203 .owner = THIS_MODULE,
204 };
205
eusb2_repeater_probe(struct platform_device * pdev)206 static int eusb2_repeater_probe(struct platform_device *pdev)
207 {
208 struct eusb2_repeater *rptr;
209 struct device *dev = &pdev->dev;
210 struct phy_provider *phy_provider;
211 struct device_node *np = dev->of_node;
212 u32 res;
213 int ret;
214
215 rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
216 if (!rptr)
217 return -ENOMEM;
218
219 rptr->dev = dev;
220 dev_set_drvdata(dev, rptr);
221
222 rptr->cfg = of_device_get_match_data(dev);
223 if (!rptr->cfg)
224 return -EINVAL;
225
226 rptr->regmap = dev_get_regmap(dev->parent, NULL);
227 if (!rptr->regmap)
228 return -ENODEV;
229
230 ret = of_property_read_u32(np, "reg", &res);
231 if (ret < 0)
232 return ret;
233
234 rptr->base = res;
235
236 ret = eusb2_repeater_init_vregs(rptr);
237 if (ret < 0) {
238 dev_err(dev, "unable to get supplies\n");
239 return ret;
240 }
241
242 rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
243 if (IS_ERR(rptr->phy)) {
244 dev_err(dev, "failed to create PHY: %d\n", ret);
245 return PTR_ERR(rptr->phy);
246 }
247
248 phy_set_drvdata(rptr->phy, rptr);
249
250 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
251 if (IS_ERR(phy_provider))
252 return PTR_ERR(phy_provider);
253
254 dev_info(dev, "Registered Qcom-eUSB2 repeater\n");
255
256 return 0;
257 }
258
eusb2_repeater_remove(struct platform_device * pdev)259 static void eusb2_repeater_remove(struct platform_device *pdev)
260 {
261 struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
262
263 if (!rptr)
264 return;
265
266 eusb2_repeater_exit(rptr->phy);
267 }
268
269 static const struct of_device_id eusb2_repeater_of_match_table[] = {
270 {
271 .compatible = "qcom,pm8550b-eusb2-repeater",
272 .data = &pm8550b_eusb2_cfg,
273 },
274 { },
275 };
276 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
277
278 static struct platform_driver eusb2_repeater_driver = {
279 .probe = eusb2_repeater_probe,
280 .remove_new = eusb2_repeater_remove,
281 .driver = {
282 .name = "qcom-eusb2-repeater",
283 .of_match_table = eusb2_repeater_of_match_table,
284 },
285 };
286
287 module_platform_driver(eusb2_repeater_driver);
288
289 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
290 MODULE_LICENSE("GPL");
291