1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2016 Linaro Ltd
4  */
5 #include <linux/module.h>
6 #include <linux/ulpi/driver.h>
7 #include <linux/ulpi/regs.h>
8 #include <linux/phy/phy.h>
9 #include <linux/pinctrl/consumer.h>
10 #include <linux/pinctrl/pinctrl-state.h>
11 #include <linux/delay.h>
12 #include <linux/clk.h>
13 
14 #define ULPI_HSIC_CFG		0x30
15 #define ULPI_HSIC_IO_CAL	0x33
16 
17 struct qcom_usb_hsic_phy {
18 	struct ulpi *ulpi;
19 	struct phy *phy;
20 	struct pinctrl *pctl;
21 	struct clk *phy_clk;
22 	struct clk *cal_clk;
23 	struct clk *cal_sleep_clk;
24 };
25 
26 static int qcom_usb_hsic_phy_power_on(struct phy *phy)
27 {
28 	struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
29 	struct ulpi *ulpi = uphy->ulpi;
30 	struct pinctrl_state *pins_default;
31 	int ret;
32 
33 	ret = clk_prepare_enable(uphy->phy_clk);
34 	if (ret)
35 		return ret;
36 
37 	ret = clk_prepare_enable(uphy->cal_clk);
38 	if (ret)
39 		goto err_cal;
40 
41 	ret = clk_prepare_enable(uphy->cal_sleep_clk);
42 	if (ret)
43 		goto err_sleep;
44 
45 	/* Set periodic calibration interval to ~2.048sec in HSIC_IO_CAL_REG */
46 	ret = ulpi_write(ulpi, ULPI_HSIC_IO_CAL, 0xff);
47 	if (ret)
48 		goto err_ulpi;
49 
50 	/* Enable periodic IO calibration in HSIC_CFG register */
51 	ret = ulpi_write(ulpi, ULPI_HSIC_CFG, 0xa8);
52 	if (ret)
53 		goto err_ulpi;
54 
55 	/* Configure pins for HSIC functionality */
56 	pins_default = pinctrl_lookup_state(uphy->pctl, PINCTRL_STATE_DEFAULT);
57 	if (IS_ERR(pins_default))
58 		return PTR_ERR(pins_default);
59 
60 	ret = pinctrl_select_state(uphy->pctl, pins_default);
61 	if (ret)
62 		goto err_ulpi;
63 
64 	 /* Enable HSIC mode in HSIC_CFG register */
65 	ret = ulpi_write(ulpi, ULPI_SET(ULPI_HSIC_CFG), 0x01);
66 	if (ret)
67 		goto err_ulpi;
68 
69 	/* Disable auto-resume */
70 	ret = ulpi_write(ulpi, ULPI_CLR(ULPI_IFC_CTRL),
71 			 ULPI_IFC_CTRL_AUTORESUME);
72 	if (ret)
73 		goto err_ulpi;
74 
75 	return ret;
76 err_ulpi:
77 	clk_disable_unprepare(uphy->cal_sleep_clk);
78 err_sleep:
79 	clk_disable_unprepare(uphy->cal_clk);
80 err_cal:
81 	clk_disable_unprepare(uphy->phy_clk);
82 	return ret;
83 }
84 
85 static int qcom_usb_hsic_phy_power_off(struct phy *phy)
86 {
87 	struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
88 
89 	clk_disable_unprepare(uphy->cal_sleep_clk);
90 	clk_disable_unprepare(uphy->cal_clk);
91 	clk_disable_unprepare(uphy->phy_clk);
92 
93 	return 0;
94 }
95 
96 static const struct phy_ops qcom_usb_hsic_phy_ops = {
97 	.power_on = qcom_usb_hsic_phy_power_on,
98 	.power_off = qcom_usb_hsic_phy_power_off,
99 	.owner = THIS_MODULE,
100 };
101 
102 static int qcom_usb_hsic_phy_probe(struct ulpi *ulpi)
103 {
104 	struct qcom_usb_hsic_phy *uphy;
105 	struct phy_provider *p;
106 	struct clk *clk;
107 
108 	uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
109 	if (!uphy)
110 		return -ENOMEM;
111 	ulpi_set_drvdata(ulpi, uphy);
112 
113 	uphy->ulpi = ulpi;
114 	uphy->pctl = devm_pinctrl_get(&ulpi->dev);
115 	if (IS_ERR(uphy->pctl))
116 		return PTR_ERR(uphy->pctl);
117 
118 	uphy->phy_clk = clk = devm_clk_get(&ulpi->dev, "phy");
119 	if (IS_ERR(clk))
120 		return PTR_ERR(clk);
121 
122 	uphy->cal_clk = clk = devm_clk_get(&ulpi->dev, "cal");
123 	if (IS_ERR(clk))
124 		return PTR_ERR(clk);
125 
126 	uphy->cal_sleep_clk = clk = devm_clk_get(&ulpi->dev, "cal_sleep");
127 	if (IS_ERR(clk))
128 		return PTR_ERR(clk);
129 
130 	uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
131 				    &qcom_usb_hsic_phy_ops);
132 	if (IS_ERR(uphy->phy))
133 		return PTR_ERR(uphy->phy);
134 	phy_set_drvdata(uphy->phy, uphy);
135 
136 	p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
137 	return PTR_ERR_OR_ZERO(p);
138 }
139 
140 static const struct of_device_id qcom_usb_hsic_phy_match[] = {
141 	{ .compatible = "qcom,usb-hsic-phy", },
142 	{ }
143 };
144 MODULE_DEVICE_TABLE(of, qcom_usb_hsic_phy_match);
145 
146 static struct ulpi_driver qcom_usb_hsic_phy_driver = {
147 	.probe = qcom_usb_hsic_phy_probe,
148 	.driver = {
149 		.name = "qcom_usb_hsic_phy",
150 		.of_match_table = qcom_usb_hsic_phy_match,
151 	},
152 };
153 module_ulpi_driver(qcom_usb_hsic_phy_driver);
154 
155 MODULE_DESCRIPTION("Qualcomm USB HSIC phy");
156 MODULE_LICENSE("GPL v2");
157