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/gpio/consumer.h>
15
16 #include "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
tusb1210_power_on(struct phy * phy)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
tusb1210_power_off(struct phy * phy)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 const struct phy_ops phy_ops = {
57 .power_on = tusb1210_power_on,
58 .power_off = tusb1210_power_off,
59 .owner = THIS_MODULE,
60 };
61
tusb1210_probe(struct ulpi * ulpi)62 static int tusb1210_probe(struct ulpi *ulpi)
63 {
64 struct tusb1210 *tusb;
65 u8 val, reg;
66
67 tusb = devm_kzalloc(&ulpi->dev, sizeof(*tusb), GFP_KERNEL);
68 if (!tusb)
69 return -ENOMEM;
70
71 tusb->gpio_reset = devm_gpiod_get_optional(&ulpi->dev, "reset",
72 GPIOD_OUT_LOW);
73 if (IS_ERR(tusb->gpio_reset))
74 return PTR_ERR(tusb->gpio_reset);
75
76 gpiod_set_value_cansleep(tusb->gpio_reset, 1);
77
78 tusb->gpio_cs = devm_gpiod_get_optional(&ulpi->dev, "cs",
79 GPIOD_OUT_LOW);
80 if (IS_ERR(tusb->gpio_cs))
81 return PTR_ERR(tusb->gpio_cs);
82
83 gpiod_set_value_cansleep(tusb->gpio_cs, 1);
84
85 /*
86 * VENDOR_SPECIFIC2 register in TUSB1210 can be used for configuring eye
87 * diagram optimization and DP/DM swap.
88 */
89
90 /* High speed output drive strength configuration */
91 device_property_read_u8(&ulpi->dev, "ihstx", &val);
92 reg = val << TUSB1210_VENDOR_SPECIFIC2_IHSTX_SHIFT;
93
94 /* High speed output impedance configuration */
95 device_property_read_u8(&ulpi->dev, "zhsdrv", &val);
96 reg |= val << TUSB1210_VENDOR_SPECIFIC2_ZHSDRV_SHIFT;
97
98 /* DP/DM swap control */
99 device_property_read_u8(&ulpi->dev, "datapolarity", &val);
100 reg |= val << TUSB1210_VENDOR_SPECIFIC2_DP_SHIFT;
101
102 if (reg) {
103 ulpi_write(ulpi, TUSB1210_VENDOR_SPECIFIC2, reg);
104 tusb->vendor_specific2 = reg;
105 }
106
107 tusb->phy = ulpi_phy_create(ulpi, &phy_ops);
108 if (IS_ERR(tusb->phy))
109 return PTR_ERR(tusb->phy);
110
111 tusb->ulpi = ulpi;
112
113 phy_set_drvdata(tusb->phy, tusb);
114 ulpi_set_drvdata(ulpi, tusb);
115 return 0;
116 }
117
tusb1210_remove(struct ulpi * ulpi)118 static void tusb1210_remove(struct ulpi *ulpi)
119 {
120 struct tusb1210 *tusb = ulpi_get_drvdata(ulpi);
121
122 ulpi_phy_destroy(ulpi, tusb->phy);
123 }
124
125 #define TI_VENDOR_ID 0x0451
126
127 static const struct ulpi_device_id tusb1210_ulpi_id[] = {
128 { TI_VENDOR_ID, 0x1507, },
129 { },
130 };
131 MODULE_DEVICE_TABLE(ulpi, tusb1210_ulpi_id);
132
133 static struct ulpi_driver tusb1210_driver = {
134 .id_table = tusb1210_ulpi_id,
135 .probe = tusb1210_probe,
136 .remove = tusb1210_remove,
137 .driver = {
138 .name = "tusb1210",
139 .owner = THIS_MODULE,
140 },
141 };
142
143 module_ulpi_driver(tusb1210_driver);
144
145 MODULE_AUTHOR("Intel Corporation");
146 MODULE_LICENSE("GPL v2");
147 MODULE_DESCRIPTION("TUSB1210 ULPI PHY driver");
148