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
eusb2_repeater_init_vregs(struct eusb2_repeater * rptr)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
eusb2_repeater_init(struct phy * phy)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
eusb2_repeater_set_mode(struct phy * phy,enum phy_mode mode,int submode)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
eusb2_repeater_exit(struct phy * phy)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
eusb2_repeater_probe(struct platform_device * pdev)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
eusb2_repeater_remove(struct platform_device * pdev)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_new = 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