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_IUSB2 0x51
28 #define EUSB2_TUNE_SQUELCH_U 0x54
29 #define EUSB2_TUNE_USB2_PREEM 0x57
30
31 #define QCOM_EUSB2_REPEATER_INIT_CFG(o, v) \
32 { \
33 .offset = o, \
34 .val = v, \
35 }
36
37 struct eusb2_repeater_init_tbl {
38 unsigned int offset;
39 unsigned int val;
40 };
41
42 struct eusb2_repeater_cfg {
43 const struct eusb2_repeater_init_tbl *init_tbl;
44 int init_tbl_num;
45 const char * const *vreg_list;
46 int num_vregs;
47 };
48
49 struct eusb2_repeater {
50 struct device *dev;
51 struct regmap *regmap;
52 struct phy *phy;
53 struct regulator_bulk_data *vregs;
54 const struct eusb2_repeater_cfg *cfg;
55 u16 base;
56 enum phy_mode mode;
57 };
58
59 static const char * const pm8550b_vreg_l[] = {
60 "vdd18", "vdd3",
61 };
62
63 static const struct eusb2_repeater_init_tbl pm8550b_init_tbl[] = {
64 QCOM_EUSB2_REPEATER_INIT_CFG(EUSB2_TUNE_IUSB2, 0x8),
65 QCOM_EUSB2_REPEATER_INIT_CFG(EUSB2_TUNE_SQUELCH_U, 0x3),
66 QCOM_EUSB2_REPEATER_INIT_CFG(EUSB2_TUNE_USB2_PREEM, 0x5),
67 };
68
69 static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
70 .init_tbl = pm8550b_init_tbl,
71 .init_tbl_num = ARRAY_SIZE(pm8550b_init_tbl),
72 .vreg_list = pm8550b_vreg_l,
73 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
74 };
75
eusb2_repeater_init_vregs(struct eusb2_repeater * rptr)76 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
77 {
78 int num = rptr->cfg->num_vregs;
79 struct device *dev = rptr->dev;
80 int i;
81
82 rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
83 if (!rptr->vregs)
84 return -ENOMEM;
85
86 for (i = 0; i < num; i++)
87 rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
88
89 return devm_regulator_bulk_get(dev, num, rptr->vregs);
90 }
91
eusb2_repeater_init(struct phy * phy)92 static int eusb2_repeater_init(struct phy *phy)
93 {
94 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
95 const struct eusb2_repeater_init_tbl *init_tbl = rptr->cfg->init_tbl;
96 int num = rptr->cfg->init_tbl_num;
97 u32 val;
98 int ret;
99 int i;
100
101 ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
102 if (ret)
103 return ret;
104
105 regmap_update_bits(rptr->regmap, rptr->base + EUSB2_EN_CTL1,
106 EUSB2_RPTR_EN, EUSB2_RPTR_EN);
107
108 for (i = 0; i < num; i++)
109 regmap_update_bits(rptr->regmap,
110 rptr->base + init_tbl[i].offset,
111 init_tbl[i].val, init_tbl[i].val);
112
113 ret = regmap_read_poll_timeout(rptr->regmap,
114 rptr->base + EUSB2_RPTR_STATUS, val,
115 val & RPTR_OK, 10, 5);
116 if (ret)
117 dev_err(rptr->dev, "initialization timed-out\n");
118
119 return ret;
120 }
121
eusb2_repeater_set_mode(struct phy * phy,enum phy_mode mode,int submode)122 static int eusb2_repeater_set_mode(struct phy *phy,
123 enum phy_mode mode, int submode)
124 {
125 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
126
127 switch (mode) {
128 case PHY_MODE_USB_HOST:
129 /*
130 * CM.Lx is prohibited when repeater is already into Lx state as
131 * per eUSB 1.2 Spec. Below implement software workaround until
132 * PHY and controller is fixing seen observation.
133 */
134 regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_EN_5,
135 F_CLK_19P2M_EN, F_CLK_19P2M_EN);
136 regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_VAL_5,
137 V_CLK_19P2M_EN, V_CLK_19P2M_EN);
138 break;
139 case PHY_MODE_USB_DEVICE:
140 /*
141 * In device mode clear host mode related workaround as there
142 * is no repeater reset available, and enable/disable of
143 * repeater doesn't clear previous value due to shared
144 * regulators (say host <-> device mode switch).
145 */
146 regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_EN_5,
147 F_CLK_19P2M_EN, 0);
148 regmap_update_bits(rptr->regmap, rptr->base + EUSB2_FORCE_VAL_5,
149 V_CLK_19P2M_EN, 0);
150 break;
151 default:
152 return -EINVAL;
153 }
154
155 return 0;
156 }
157
eusb2_repeater_exit(struct phy * phy)158 static int eusb2_repeater_exit(struct phy *phy)
159 {
160 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
161
162 return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
163 }
164
165 static const struct phy_ops eusb2_repeater_ops = {
166 .init = eusb2_repeater_init,
167 .exit = eusb2_repeater_exit,
168 .set_mode = eusb2_repeater_set_mode,
169 .owner = THIS_MODULE,
170 };
171
eusb2_repeater_probe(struct platform_device * pdev)172 static int eusb2_repeater_probe(struct platform_device *pdev)
173 {
174 struct eusb2_repeater *rptr;
175 struct device *dev = &pdev->dev;
176 struct phy_provider *phy_provider;
177 struct device_node *np = dev->of_node;
178 u32 res;
179 int ret;
180
181 rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
182 if (!rptr)
183 return -ENOMEM;
184
185 rptr->dev = dev;
186 dev_set_drvdata(dev, rptr);
187
188 rptr->cfg = of_device_get_match_data(dev);
189 if (!rptr->cfg)
190 return -EINVAL;
191
192 rptr->regmap = dev_get_regmap(dev->parent, NULL);
193 if (!rptr->regmap)
194 return -ENODEV;
195
196 ret = of_property_read_u32(np, "reg", &res);
197 if (ret < 0)
198 return ret;
199
200 rptr->base = res;
201
202 ret = eusb2_repeater_init_vregs(rptr);
203 if (ret < 0) {
204 dev_err(dev, "unable to get supplies\n");
205 return ret;
206 }
207
208 rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
209 if (IS_ERR(rptr->phy)) {
210 dev_err(dev, "failed to create PHY: %d\n", ret);
211 return PTR_ERR(rptr->phy);
212 }
213
214 phy_set_drvdata(rptr->phy, rptr);
215
216 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
217 if (IS_ERR(phy_provider))
218 return PTR_ERR(phy_provider);
219
220 dev_info(dev, "Registered Qcom-eUSB2 repeater\n");
221
222 return 0;
223 }
224
eusb2_repeater_remove(struct platform_device * pdev)225 static void eusb2_repeater_remove(struct platform_device *pdev)
226 {
227 struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
228
229 if (!rptr)
230 return;
231
232 eusb2_repeater_exit(rptr->phy);
233 }
234
235 static const struct of_device_id eusb2_repeater_of_match_table[] = {
236 {
237 .compatible = "qcom,pm8550b-eusb2-repeater",
238 .data = &pm8550b_eusb2_cfg,
239 },
240 { },
241 };
242 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
243
244 static struct platform_driver eusb2_repeater_driver = {
245 .probe = eusb2_repeater_probe,
246 .remove_new = eusb2_repeater_remove,
247 .driver = {
248 .name = "qcom-eusb2-repeater",
249 .of_match_table = eusb2_repeater_of_match_table,
250 },
251 };
252
253 module_platform_driver(eusb2_repeater_driver);
254
255 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
256 MODULE_LICENSE("GPL");
257