xref: /openbmc/linux/drivers/phy/qualcomm/phy-qcom-usb-hsic.c (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
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  
qcom_usb_hsic_phy_power_on(struct phy * phy)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  		ret = PTR_ERR(pins_default);
59  		goto err_ulpi;
60  	}
61  
62  	ret = pinctrl_select_state(uphy->pctl, pins_default);
63  	if (ret)
64  		goto err_ulpi;
65  
66  	 /* Enable HSIC mode in HSIC_CFG register */
67  	ret = ulpi_write(ulpi, ULPI_SET(ULPI_HSIC_CFG), 0x01);
68  	if (ret)
69  		goto err_ulpi;
70  
71  	/* Disable auto-resume */
72  	ret = ulpi_write(ulpi, ULPI_CLR(ULPI_IFC_CTRL),
73  			 ULPI_IFC_CTRL_AUTORESUME);
74  	if (ret)
75  		goto err_ulpi;
76  
77  	return ret;
78  err_ulpi:
79  	clk_disable_unprepare(uphy->cal_sleep_clk);
80  err_sleep:
81  	clk_disable_unprepare(uphy->cal_clk);
82  err_cal:
83  	clk_disable_unprepare(uphy->phy_clk);
84  	return ret;
85  }
86  
qcom_usb_hsic_phy_power_off(struct phy * phy)87  static int qcom_usb_hsic_phy_power_off(struct phy *phy)
88  {
89  	struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
90  
91  	clk_disable_unprepare(uphy->cal_sleep_clk);
92  	clk_disable_unprepare(uphy->cal_clk);
93  	clk_disable_unprepare(uphy->phy_clk);
94  
95  	return 0;
96  }
97  
98  static const struct phy_ops qcom_usb_hsic_phy_ops = {
99  	.power_on = qcom_usb_hsic_phy_power_on,
100  	.power_off = qcom_usb_hsic_phy_power_off,
101  	.owner = THIS_MODULE,
102  };
103  
qcom_usb_hsic_phy_probe(struct ulpi * ulpi)104  static int qcom_usb_hsic_phy_probe(struct ulpi *ulpi)
105  {
106  	struct qcom_usb_hsic_phy *uphy;
107  	struct phy_provider *p;
108  	struct clk *clk;
109  
110  	uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
111  	if (!uphy)
112  		return -ENOMEM;
113  	ulpi_set_drvdata(ulpi, uphy);
114  
115  	uphy->ulpi = ulpi;
116  	uphy->pctl = devm_pinctrl_get(&ulpi->dev);
117  	if (IS_ERR(uphy->pctl))
118  		return PTR_ERR(uphy->pctl);
119  
120  	uphy->phy_clk = clk = devm_clk_get(&ulpi->dev, "phy");
121  	if (IS_ERR(clk))
122  		return PTR_ERR(clk);
123  
124  	uphy->cal_clk = clk = devm_clk_get(&ulpi->dev, "cal");
125  	if (IS_ERR(clk))
126  		return PTR_ERR(clk);
127  
128  	uphy->cal_sleep_clk = clk = devm_clk_get(&ulpi->dev, "cal_sleep");
129  	if (IS_ERR(clk))
130  		return PTR_ERR(clk);
131  
132  	uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
133  				    &qcom_usb_hsic_phy_ops);
134  	if (IS_ERR(uphy->phy))
135  		return PTR_ERR(uphy->phy);
136  	phy_set_drvdata(uphy->phy, uphy);
137  
138  	p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
139  	return PTR_ERR_OR_ZERO(p);
140  }
141  
142  static const struct of_device_id qcom_usb_hsic_phy_match[] = {
143  	{ .compatible = "qcom,usb-hsic-phy", },
144  	{ }
145  };
146  MODULE_DEVICE_TABLE(of, qcom_usb_hsic_phy_match);
147  
148  static struct ulpi_driver qcom_usb_hsic_phy_driver = {
149  	.probe = qcom_usb_hsic_phy_probe,
150  	.driver = {
151  		.name = "qcom_usb_hsic_phy",
152  		.of_match_table = qcom_usb_hsic_phy_match,
153  	},
154  };
155  module_ulpi_driver(qcom_usb_hsic_phy_driver);
156  
157  MODULE_DESCRIPTION("Qualcomm USB HSIC phy");
158  MODULE_LICENSE("GPL v2");
159