xref: /openbmc/linux/drivers/phy/ti/phy-tusb1210.c (revision ba61bb17)
1 /**
2  * tusb1210.c - TUSB1210 USB ULPI PHY driver
3  *
4  * Copyright (C) 2015 Intel Corporation
5  *
6  * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 #include <linux/module.h>
13 #include <linux/ulpi/driver.h>
14 #include <linux/ulpi/regs.h>
15 #include <linux/gpio/consumer.h>
16 #include <linux/phy/ulpi_phy.h>
17 
18 #define TUSB1210_VENDOR_SPECIFIC2		0x80
19 #define TUSB1210_VENDOR_SPECIFIC2_IHSTX_SHIFT	0
20 #define TUSB1210_VENDOR_SPECIFIC2_ZHSDRV_SHIFT	4
21 #define TUSB1210_VENDOR_SPECIFIC2_DP_SHIFT	6
22 
23 struct tusb1210 {
24 	struct ulpi *ulpi;
25 	struct phy *phy;
26 	struct gpio_desc *gpio_reset;
27 	struct gpio_desc *gpio_cs;
28 	u8 vendor_specific2;
29 };
30 
31 static int tusb1210_power_on(struct phy *phy)
32 {
33 	struct tusb1210 *tusb = phy_get_drvdata(phy);
34 
35 	gpiod_set_value_cansleep(tusb->gpio_reset, 1);
36 	gpiod_set_value_cansleep(tusb->gpio_cs, 1);
37 
38 	/* Restore the optional eye diagram optimization value */
39 	if (tusb->vendor_specific2)
40 		ulpi_write(tusb->ulpi, TUSB1210_VENDOR_SPECIFIC2,
41 			   tusb->vendor_specific2);
42 
43 	return 0;
44 }
45 
46 static int tusb1210_power_off(struct phy *phy)
47 {
48 	struct tusb1210 *tusb = phy_get_drvdata(phy);
49 
50 	gpiod_set_value_cansleep(tusb->gpio_reset, 0);
51 	gpiod_set_value_cansleep(tusb->gpio_cs, 0);
52 
53 	return 0;
54 }
55 
56 static int tusb1210_set_mode(struct phy *phy, enum phy_mode mode)
57 {
58 	struct tusb1210 *tusb = phy_get_drvdata(phy);
59 	int ret;
60 
61 	ret = ulpi_read(tusb->ulpi, ULPI_OTG_CTRL);
62 	if (ret < 0)
63 		return ret;
64 
65 	switch (mode) {
66 	case PHY_MODE_USB_HOST:
67 		ret |= (ULPI_OTG_CTRL_DRVVBUS_EXT
68 			| ULPI_OTG_CTRL_ID_PULLUP
69 			| ULPI_OTG_CTRL_DP_PULLDOWN
70 			| ULPI_OTG_CTRL_DM_PULLDOWN);
71 		ulpi_write(tusb->ulpi, ULPI_OTG_CTRL, ret);
72 		ret |= ULPI_OTG_CTRL_DRVVBUS;
73 		break;
74 	case PHY_MODE_USB_DEVICE:
75 		ret &= ~(ULPI_OTG_CTRL_DRVVBUS
76 			 | ULPI_OTG_CTRL_DP_PULLDOWN
77 			 | ULPI_OTG_CTRL_DM_PULLDOWN);
78 		ulpi_write(tusb->ulpi, ULPI_OTG_CTRL, ret);
79 		ret &= ~ULPI_OTG_CTRL_DRVVBUS_EXT;
80 		break;
81 	default:
82 		/* nothing */
83 		return 0;
84 	}
85 
86 	return ulpi_write(tusb->ulpi, ULPI_OTG_CTRL, ret);
87 }
88 
89 static const struct phy_ops phy_ops = {
90 	.power_on = tusb1210_power_on,
91 	.power_off = tusb1210_power_off,
92 	.set_mode = tusb1210_set_mode,
93 	.owner = THIS_MODULE,
94 };
95 
96 static int tusb1210_probe(struct ulpi *ulpi)
97 {
98 	struct tusb1210 *tusb;
99 	u8 val, reg;
100 
101 	tusb = devm_kzalloc(&ulpi->dev, sizeof(*tusb), GFP_KERNEL);
102 	if (!tusb)
103 		return -ENOMEM;
104 
105 	tusb->gpio_reset = devm_gpiod_get_optional(&ulpi->dev, "reset",
106 						   GPIOD_OUT_LOW);
107 	if (IS_ERR(tusb->gpio_reset))
108 		return PTR_ERR(tusb->gpio_reset);
109 
110 	gpiod_set_value_cansleep(tusb->gpio_reset, 1);
111 
112 	tusb->gpio_cs = devm_gpiod_get_optional(&ulpi->dev, "cs",
113 						GPIOD_OUT_LOW);
114 	if (IS_ERR(tusb->gpio_cs))
115 		return PTR_ERR(tusb->gpio_cs);
116 
117 	gpiod_set_value_cansleep(tusb->gpio_cs, 1);
118 
119 	/*
120 	 * VENDOR_SPECIFIC2 register in TUSB1210 can be used for configuring eye
121 	 * diagram optimization and DP/DM swap.
122 	 */
123 
124 	/* High speed output drive strength configuration */
125 	device_property_read_u8(&ulpi->dev, "ihstx", &val);
126 	reg = val << TUSB1210_VENDOR_SPECIFIC2_IHSTX_SHIFT;
127 
128 	/* High speed output impedance configuration */
129 	device_property_read_u8(&ulpi->dev, "zhsdrv", &val);
130 	reg |= val << TUSB1210_VENDOR_SPECIFIC2_ZHSDRV_SHIFT;
131 
132 	/* DP/DM swap control */
133 	device_property_read_u8(&ulpi->dev, "datapolarity", &val);
134 	reg |= val << TUSB1210_VENDOR_SPECIFIC2_DP_SHIFT;
135 
136 	if (reg) {
137 		ulpi_write(ulpi, TUSB1210_VENDOR_SPECIFIC2, reg);
138 		tusb->vendor_specific2 = reg;
139 	}
140 
141 	tusb->phy = ulpi_phy_create(ulpi, &phy_ops);
142 	if (IS_ERR(tusb->phy))
143 		return PTR_ERR(tusb->phy);
144 
145 	tusb->ulpi = ulpi;
146 
147 	phy_set_drvdata(tusb->phy, tusb);
148 	ulpi_set_drvdata(ulpi, tusb);
149 	return 0;
150 }
151 
152 static void tusb1210_remove(struct ulpi *ulpi)
153 {
154 	struct tusb1210 *tusb = ulpi_get_drvdata(ulpi);
155 
156 	ulpi_phy_destroy(ulpi, tusb->phy);
157 }
158 
159 #define TI_VENDOR_ID 0x0451
160 
161 static const struct ulpi_device_id tusb1210_ulpi_id[] = {
162 	{ TI_VENDOR_ID, 0x1507, },  /* TUSB1210 */
163 	{ TI_VENDOR_ID, 0x1508, },  /* TUSB1211 */
164 	{ },
165 };
166 MODULE_DEVICE_TABLE(ulpi, tusb1210_ulpi_id);
167 
168 static struct ulpi_driver tusb1210_driver = {
169 	.id_table = tusb1210_ulpi_id,
170 	.probe = tusb1210_probe,
171 	.remove = tusb1210_remove,
172 	.driver = {
173 		.name = "tusb1210",
174 		.owner = THIS_MODULE,
175 	},
176 };
177 
178 module_ulpi_driver(tusb1210_driver);
179 
180 MODULE_AUTHOR("Intel Corporation");
181 MODULE_LICENSE("GPL v2");
182 MODULE_DESCRIPTION("TUSB1210 ULPI PHY driver");
183