1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Meson GXL and GXM USB2 PHY driver
4 *
5 * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
6 */
7
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/mod_devicetable.h>
12 #include <linux/module.h>
13 #include <linux/regmap.h>
14 #include <linux/reset.h>
15 #include <linux/phy/phy.h>
16 #include <linux/platform_device.h>
17
18 /* bits [31:27] are read-only */
19 #define U2P_R0 0x0
20 #define U2P_R0_BYPASS_SEL BIT(0)
21 #define U2P_R0_BYPASS_DM_EN BIT(1)
22 #define U2P_R0_BYPASS_DP_EN BIT(2)
23 #define U2P_R0_TXBITSTUFF_ENH BIT(3)
24 #define U2P_R0_TXBITSTUFF_EN BIT(4)
25 #define U2P_R0_DM_PULLDOWN BIT(5)
26 #define U2P_R0_DP_PULLDOWN BIT(6)
27 #define U2P_R0_DP_VBUS_VLD_EXT_SEL BIT(7)
28 #define U2P_R0_DP_VBUS_VLD_EXT BIT(8)
29 #define U2P_R0_ADP_PRB_EN BIT(9)
30 #define U2P_R0_ADP_DISCHARGE BIT(10)
31 #define U2P_R0_ADP_CHARGE BIT(11)
32 #define U2P_R0_DRV_VBUS BIT(12)
33 #define U2P_R0_ID_PULLUP BIT(13)
34 #define U2P_R0_LOOPBACK_EN_B BIT(14)
35 #define U2P_R0_OTG_DISABLE BIT(15)
36 #define U2P_R0_COMMON_ONN BIT(16)
37 #define U2P_R0_FSEL_MASK GENMASK(19, 17)
38 #define U2P_R0_REF_CLK_SEL_MASK GENMASK(21, 20)
39 #define U2P_R0_POWER_ON_RESET BIT(22)
40 #define U2P_R0_V_ATE_TEST_EN_B_MASK GENMASK(24, 23)
41 #define U2P_R0_ID_SET_ID_DQ BIT(25)
42 #define U2P_R0_ATE_RESET BIT(26)
43 #define U2P_R0_FSV_MINUS BIT(27)
44 #define U2P_R0_FSV_PLUS BIT(28)
45 #define U2P_R0_BYPASS_DM_DATA BIT(29)
46 #define U2P_R0_BYPASS_DP_DATA BIT(30)
47
48 #define U2P_R1 0x4
49 #define U2P_R1_BURN_IN_TEST BIT(0)
50 #define U2P_R1_ACA_ENABLE BIT(1)
51 #define U2P_R1_DCD_ENABLE BIT(2)
52 #define U2P_R1_VDAT_SRC_EN_B BIT(3)
53 #define U2P_R1_VDAT_DET_EN_B BIT(4)
54 #define U2P_R1_CHARGES_SEL BIT(5)
55 #define U2P_R1_TX_PREEMP_PULSE_TUNE BIT(6)
56 #define U2P_R1_TX_PREEMP_AMP_TUNE_MASK GENMASK(8, 7)
57 #define U2P_R1_TX_RES_TUNE_MASK GENMASK(10, 9)
58 #define U2P_R1_TX_RISE_TUNE_MASK GENMASK(12, 11)
59 #define U2P_R1_TX_VREF_TUNE_MASK GENMASK(16, 13)
60 #define U2P_R1_TX_FSLS_TUNE_MASK GENMASK(20, 17)
61 #define U2P_R1_TX_HSXV_TUNE_MASK GENMASK(22, 21)
62 #define U2P_R1_OTG_TUNE_MASK GENMASK(25, 23)
63 #define U2P_R1_SQRX_TUNE_MASK GENMASK(28, 26)
64 #define U2P_R1_COMP_DIS_TUNE_MASK GENMASK(31, 29)
65
66 /* bits [31:14] are read-only */
67 #define U2P_R2 0x8
68 #define U2P_R2_TESTDATA_IN_MASK GENMASK(7, 0)
69 #define U2P_R2_TESTADDR_MASK GENMASK(11, 8)
70 #define U2P_R2_TESTDATA_OUT_SEL BIT(12)
71 #define U2P_R2_TESTCLK BIT(13)
72 #define U2P_R2_TESTDATA_OUT_MASK GENMASK(17, 14)
73 #define U2P_R2_ACA_PIN_RANGE_C BIT(18)
74 #define U2P_R2_ACA_PIN_RANGE_B BIT(19)
75 #define U2P_R2_ACA_PIN_RANGE_A BIT(20)
76 #define U2P_R2_ACA_PIN_GND BIT(21)
77 #define U2P_R2_ACA_PIN_FLOAT BIT(22)
78 #define U2P_R2_CHARGE_DETECT BIT(23)
79 #define U2P_R2_DEVICE_SESSION_VALID BIT(24)
80 #define U2P_R2_ADP_PROBE BIT(25)
81 #define U2P_R2_ADP_SENSE BIT(26)
82 #define U2P_R2_SESSION_END BIT(27)
83 #define U2P_R2_VBUS_VALID BIT(28)
84 #define U2P_R2_B_VALID BIT(29)
85 #define U2P_R2_A_VALID BIT(30)
86 #define U2P_R2_ID_DIG BIT(31)
87
88 #define U2P_R3 0xc
89
90 #define RESET_COMPLETE_TIME 500
91
92 struct phy_meson_gxl_usb2_priv {
93 struct regmap *regmap;
94 enum phy_mode mode;
95 int is_enabled;
96 struct clk *clk;
97 struct reset_control *reset;
98 };
99
100 static const struct regmap_config phy_meson_gxl_usb2_regmap_conf = {
101 .reg_bits = 8,
102 .val_bits = 32,
103 .reg_stride = 4,
104 .max_register = U2P_R3,
105 };
106
phy_meson_gxl_usb2_init(struct phy * phy)107 static int phy_meson_gxl_usb2_init(struct phy *phy)
108 {
109 struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
110 int ret;
111
112 ret = reset_control_reset(priv->reset);
113 if (ret)
114 return ret;
115
116 ret = clk_prepare_enable(priv->clk);
117 if (ret) {
118 reset_control_rearm(priv->reset);
119 return ret;
120 }
121
122 return 0;
123 }
124
phy_meson_gxl_usb2_exit(struct phy * phy)125 static int phy_meson_gxl_usb2_exit(struct phy *phy)
126 {
127 struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
128
129 clk_disable_unprepare(priv->clk);
130 reset_control_rearm(priv->reset);
131
132 return 0;
133 }
134
phy_meson_gxl_usb2_reset(struct phy * phy)135 static int phy_meson_gxl_usb2_reset(struct phy *phy)
136 {
137 struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
138
139 if (priv->is_enabled) {
140 /* reset the PHY and wait until settings are stabilized */
141 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
142 U2P_R0_POWER_ON_RESET);
143 udelay(RESET_COMPLETE_TIME);
144 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
145 0);
146 udelay(RESET_COMPLETE_TIME);
147 }
148
149 return 0;
150 }
151
phy_meson_gxl_usb2_set_mode(struct phy * phy,enum phy_mode mode,int submode)152 static int phy_meson_gxl_usb2_set_mode(struct phy *phy,
153 enum phy_mode mode, int submode)
154 {
155 struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
156
157 switch (mode) {
158 case PHY_MODE_USB_HOST:
159 case PHY_MODE_USB_OTG:
160 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DM_PULLDOWN,
161 U2P_R0_DM_PULLDOWN);
162 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DP_PULLDOWN,
163 U2P_R0_DP_PULLDOWN);
164 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_ID_PULLUP,
165 U2P_R0_ID_PULLUP);
166 break;
167
168 case PHY_MODE_USB_DEVICE:
169 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DM_PULLDOWN,
170 0);
171 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DP_PULLDOWN,
172 0);
173 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_ID_PULLUP,
174 U2P_R0_ID_PULLUP);
175 break;
176
177 default:
178 return -EINVAL;
179 }
180
181 phy_meson_gxl_usb2_reset(phy);
182
183 priv->mode = mode;
184
185 return 0;
186 }
187
phy_meson_gxl_usb2_power_off(struct phy * phy)188 static int phy_meson_gxl_usb2_power_off(struct phy *phy)
189 {
190 struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
191
192 priv->is_enabled = 0;
193
194 /* power off the PHY by putting it into reset mode */
195 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
196 U2P_R0_POWER_ON_RESET);
197
198 return 0;
199 }
200
phy_meson_gxl_usb2_power_on(struct phy * phy)201 static int phy_meson_gxl_usb2_power_on(struct phy *phy)
202 {
203 struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
204 int ret;
205
206 priv->is_enabled = 1;
207
208 /* power on the PHY by taking it out of reset mode */
209 regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET, 0);
210
211 ret = phy_meson_gxl_usb2_set_mode(phy, priv->mode, 0);
212 if (ret) {
213 phy_meson_gxl_usb2_power_off(phy);
214
215 dev_err(&phy->dev, "Failed to initialize PHY with mode %d\n",
216 priv->mode);
217 return ret;
218 }
219
220 return 0;
221 }
222
223 static const struct phy_ops phy_meson_gxl_usb2_ops = {
224 .init = phy_meson_gxl_usb2_init,
225 .exit = phy_meson_gxl_usb2_exit,
226 .power_on = phy_meson_gxl_usb2_power_on,
227 .power_off = phy_meson_gxl_usb2_power_off,
228 .set_mode = phy_meson_gxl_usb2_set_mode,
229 .reset = phy_meson_gxl_usb2_reset,
230 .owner = THIS_MODULE,
231 };
232
phy_meson_gxl_usb2_probe(struct platform_device * pdev)233 static int phy_meson_gxl_usb2_probe(struct platform_device *pdev)
234 {
235 struct device *dev = &pdev->dev;
236 struct phy_provider *phy_provider;
237 struct phy_meson_gxl_usb2_priv *priv;
238 struct phy *phy;
239 void __iomem *base;
240 int ret;
241
242 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
243 if (!priv)
244 return -ENOMEM;
245
246 platform_set_drvdata(pdev, priv);
247
248 base = devm_platform_ioremap_resource(pdev, 0);
249 if (IS_ERR(base))
250 return PTR_ERR(base);
251
252 /* start in host mode */
253 priv->mode = PHY_MODE_USB_HOST;
254
255 priv->regmap = devm_regmap_init_mmio(dev, base,
256 &phy_meson_gxl_usb2_regmap_conf);
257 if (IS_ERR(priv->regmap))
258 return PTR_ERR(priv->regmap);
259
260 priv->clk = devm_clk_get_optional(dev, "phy");
261 if (IS_ERR(priv->clk))
262 return PTR_ERR(priv->clk);
263
264 priv->reset = devm_reset_control_get_optional_shared(dev, "phy");
265 if (IS_ERR(priv->reset))
266 return PTR_ERR(priv->reset);
267
268 phy = devm_phy_create(dev, NULL, &phy_meson_gxl_usb2_ops);
269 if (IS_ERR(phy)) {
270 ret = PTR_ERR(phy);
271 if (ret != -EPROBE_DEFER)
272 dev_err(dev, "failed to create PHY\n");
273
274 return ret;
275 }
276
277 phy_set_drvdata(phy, priv);
278
279 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
280
281 return PTR_ERR_OR_ZERO(phy_provider);
282 }
283
284 static const struct of_device_id phy_meson_gxl_usb2_of_match[] = {
285 { .compatible = "amlogic,meson-gxl-usb2-phy", },
286 { },
287 };
288 MODULE_DEVICE_TABLE(of, phy_meson_gxl_usb2_of_match);
289
290 static struct platform_driver phy_meson_gxl_usb2_driver = {
291 .probe = phy_meson_gxl_usb2_probe,
292 .driver = {
293 .name = "phy-meson-gxl-usb2",
294 .of_match_table = phy_meson_gxl_usb2_of_match,
295 },
296 };
297 module_platform_driver(phy_meson_gxl_usb2_driver);
298
299 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
300 MODULE_DESCRIPTION("Meson GXL and GXM USB2 PHY driver");
301 MODULE_LICENSE("GPL v2");
302