172 lines · c
1/*2 * HID over I2C Open Firmware Subclass3 *4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France6 * Copyright (c) 2012 Red Hat, Inc7 *8 * This code was forked out of the core code, which was partly based on9 * "USB HID support for Linux":10 *11 * Copyright (c) 1999 Andreas Gal12 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>13 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc14 * Copyright (c) 2007-2008 Oliver Neukum15 * Copyright (c) 2006-2010 Jiri Kosina16 *17 * This file is subject to the terms and conditions of the GNU General Public18 * License. See the file COPYING in the main directory of this archive for19 * more details.20 */21 22#include <linux/delay.h>23#include <linux/device.h>24#include <linux/gpio/consumer.h>25#include <linux/hid.h>26#include <linux/i2c.h>27#include <linux/kernel.h>28#include <linux/module.h>29#include <linux/of.h>30#include <linux/pm.h>31#include <linux/regulator/consumer.h>32 33#include "i2c-hid.h"34 35struct i2c_hid_of {36 struct i2chid_ops ops;37 38 struct i2c_client *client;39 struct gpio_desc *reset_gpio;40 struct regulator_bulk_data supplies[2];41 int post_power_delay_ms;42 int post_reset_delay_ms;43};44 45static int i2c_hid_of_power_up(struct i2chid_ops *ops)46{47 struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);48 struct device *dev = &ihid_of->client->dev;49 int ret;50 51 ret = regulator_bulk_enable(ARRAY_SIZE(ihid_of->supplies),52 ihid_of->supplies);53 if (ret) {54 dev_warn(dev, "Failed to enable supplies: %d\n", ret);55 return ret;56 }57 58 if (ihid_of->post_power_delay_ms)59 msleep(ihid_of->post_power_delay_ms);60 61 gpiod_set_value_cansleep(ihid_of->reset_gpio, 0);62 if (ihid_of->post_reset_delay_ms)63 msleep(ihid_of->post_reset_delay_ms);64 65 return 0;66}67 68static void i2c_hid_of_power_down(struct i2chid_ops *ops)69{70 struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);71 72 gpiod_set_value_cansleep(ihid_of->reset_gpio, 1);73 regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies),74 ihid_of->supplies);75}76 77static int i2c_hid_of_probe(struct i2c_client *client)78{79 struct device *dev = &client->dev;80 struct i2c_hid_of *ihid_of;81 u16 hid_descriptor_address;82 u32 quirks = 0;83 int ret;84 u32 val;85 86 ihid_of = devm_kzalloc(dev, sizeof(*ihid_of), GFP_KERNEL);87 if (!ihid_of)88 return -ENOMEM;89 90 ihid_of->client = client;91 ihid_of->ops.power_up = i2c_hid_of_power_up;92 ihid_of->ops.power_down = i2c_hid_of_power_down;93 94 ret = device_property_read_u32(dev, "hid-descr-addr", &val);95 if (ret) {96 dev_err(dev, "HID register address not provided\n");97 return -ENODEV;98 }99 if (val >> 16) {100 dev_err(dev, "Bad HID register address: 0x%08x\n", val);101 return -EINVAL;102 }103 hid_descriptor_address = val;104 105 if (!device_property_read_u32(dev, "post-power-on-delay-ms", &val))106 ihid_of->post_power_delay_ms = val;107 108 /*109 * Note this is a kernel internal device-property set by x86 platform code,110 * this MUST not be used in devicetree files without first adding it to111 * the DT bindings.112 */113 if (!device_property_read_u32(dev, "post-reset-deassert-delay-ms", &val))114 ihid_of->post_reset_delay_ms = val;115 116 /* Start out with reset asserted */117 ihid_of->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);118 if (IS_ERR(ihid_of->reset_gpio))119 return PTR_ERR(ihid_of->reset_gpio);120 121 ihid_of->supplies[0].supply = "vdd";122 ihid_of->supplies[1].supply = "vddl";123 ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ihid_of->supplies),124 ihid_of->supplies);125 if (ret)126 return ret;127 128 if (device_property_read_bool(dev, "touchscreen-inverted-x"))129 quirks |= HID_QUIRK_X_INVERT;130 131 if (device_property_read_bool(dev, "touchscreen-inverted-y"))132 quirks |= HID_QUIRK_Y_INVERT;133 134 return i2c_hid_core_probe(client, &ihid_of->ops,135 hid_descriptor_address, quirks);136}137 138#ifdef CONFIG_OF139static const struct of_device_id i2c_hid_of_match[] = {140 { .compatible = "hid-over-i2c" },141 {},142};143MODULE_DEVICE_TABLE(of, i2c_hid_of_match);144#endif145 146static const struct i2c_device_id i2c_hid_of_id_table[] = {147 { "hid", 0 },148 { "hid-over-i2c", 0 },149 { },150};151MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table);152 153static struct i2c_driver i2c_hid_of_driver = {154 .driver = {155 .name = "i2c_hid_of",156 .pm = &i2c_hid_core_pm,157 .probe_type = PROBE_PREFER_ASYNCHRONOUS,158 .of_match_table = of_match_ptr(i2c_hid_of_match),159 },160 161 .probe = i2c_hid_of_probe,162 .remove = i2c_hid_core_remove,163 .shutdown = i2c_hid_core_shutdown,164 .id_table = i2c_hid_of_id_table,165};166 167module_i2c_driver(i2c_hid_of_driver);168 169MODULE_DESCRIPTION("HID over I2C OF driver");170MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");171MODULE_LICENSE("GPL");172