tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
23struct 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
31static 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
46static 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
56static struct phy_ops phy_ops = {
57 .power_on = tusb1210_power_on,
58 .power_off = tusb1210_power_off,
59 .owner = THIS_MODULE,
60};
61
62static int tusb1210_probe(struct ulpi *ulpi)
63{
64 struct gpio_desc *gpio;
65 struct tusb1210 *tusb;
66 u8 val, reg;
67 int ret;
68
69 tusb = devm_kzalloc(&ulpi->dev, sizeof(*tusb), GFP_KERNEL);
70 if (!tusb)
71 return -ENOMEM;
72
73 gpio = devm_gpiod_get(&ulpi->dev, "reset");
74 if (!IS_ERR(gpio)) {
75 ret = gpiod_direction_output(gpio, 0);
76 if (ret)
77 return ret;
78 gpiod_set_value_cansleep(gpio, 1);
79 tusb->gpio_reset = gpio;
80 }
81
82 gpio = devm_gpiod_get(&ulpi->dev, "cs");
83 if (!IS_ERR(gpio)) {
84 ret = gpiod_direction_output(gpio, 0);
85 if (ret)
86 return ret;
87 gpiod_set_value_cansleep(gpio, 1);
88 tusb->gpio_cs = gpio;
89 }
90
91 /*
92 * VENDOR_SPECIFIC2 register in TUSB1210 can be used for configuring eye
93 * diagram optimization and DP/DM swap.
94 */
95
96 /* High speed output drive strength configuration */
97 device_property_read_u8(&ulpi->dev, "ihstx", &val);
98 reg = val << TUSB1210_VENDOR_SPECIFIC2_IHSTX_SHIFT;
99
100 /* High speed output impedance configuration */
101 device_property_read_u8(&ulpi->dev, "zhsdrv", &val);
102 reg |= val << TUSB1210_VENDOR_SPECIFIC2_ZHSDRV_SHIFT;
103
104 /* DP/DM swap control */
105 device_property_read_u8(&ulpi->dev, "datapolarity", &val);
106 reg |= val << TUSB1210_VENDOR_SPECIFIC2_DP_SHIFT;
107
108 if (reg) {
109 ulpi_write(ulpi, TUSB1210_VENDOR_SPECIFIC2, reg);
110 tusb->vendor_specific2 = reg;
111 }
112
113 tusb->phy = ulpi_phy_create(ulpi, &phy_ops);
114 if (IS_ERR(tusb->phy))
115 return PTR_ERR(tusb->phy);
116
117 tusb->ulpi = ulpi;
118
119 phy_set_drvdata(tusb->phy, tusb);
120 ulpi_set_drvdata(ulpi, tusb);
121 return 0;
122}
123
124static void tusb1210_remove(struct ulpi *ulpi)
125{
126 struct tusb1210 *tusb = ulpi_get_drvdata(ulpi);
127
128 ulpi_phy_destroy(ulpi, tusb->phy);
129}
130
131#define TI_VENDOR_ID 0x0451
132
133static const struct ulpi_device_id tusb1210_ulpi_id[] = {
134 { TI_VENDOR_ID, 0x1507, },
135 { },
136};
137MODULE_DEVICE_TABLE(ulpi, tusb1210_ulpi_id);
138
139static struct ulpi_driver tusb1210_driver = {
140 .id_table = tusb1210_ulpi_id,
141 .probe = tusb1210_probe,
142 .remove = tusb1210_remove,
143 .driver = {
144 .name = "tusb1210",
145 .owner = THIS_MODULE,
146 },
147};
148
149module_ulpi_driver(tusb1210_driver);
150
151MODULE_AUTHOR("Intel Corporation");
152MODULE_LICENSE("GPL v2");
153MODULE_DESCRIPTION("TUSB1210 ULPI PHY driver");