drivers/hid/i2c-hid/i2c-hid-of.c

   1 /*
   2  * HID over I2C Open Firmware Subclass
   3  *
   4  * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
   5  * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
   6  * Copyright (c) 2012 Red Hat, Inc
   7  *
   8  * This code was forked out of the core code, which was partly based on
   9  * "USB HID support for Linux":
  10  *
  11  *  Copyright (c) 1999 Andreas Gal
  12  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
  13  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
  14  *  Copyright (c) 2007-2008 Oliver Neukum
  15  *  Copyright (c) 2006-2010 Jiri Kosina
  16  *
  17  * This file is subject to the terms and conditions of the GNU General Public
  18  * License.  See the file COPYING in the main directory of this archive for
  19  * more details.
  20  */
  21
  22 #include <linux/delay.h>
  23 #include <linux/device.h>
  24 #include <linux/hid.h>
  25 #include <linux/i2c.h>
  26 #include <linux/kernel.h>
  27 #include <linux/module.h>
  28 #include <linux/of.h>
  29 #include <linux/pm.h>
  30 #include <linux/regulator/consumer.h>
  31
  32 #include "i2c-hid.h"
  33
  34 struct i2c_hid_of {
  35         struct i2chid_ops ops;
  36
  37         struct i2c_client *client;
  38         struct regulator_bulk_data supplies[2];
  39         int post_power_delay_ms;
  40 };
  41
  42 static int i2c_hid_of_power_up(struct i2chid_ops *ops)
  43 {
  44         struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
  45         struct device *dev = &ihid_of->client->dev;
  46         int ret;
  47
  48         ret = regulator_bulk_enable(ARRAY_SIZE(ihid_of->supplies),
  49                                     ihid_of->supplies);
  50         if (ret) {
  51                 dev_warn(dev, "Failed to enable supplies: %d\n", ret);
  52                 return ret;
  53         }
  54
  55         if (ihid_of->post_power_delay_ms)
  56                 msleep(ihid_of->post_power_delay_ms);
  57
  58         return 0;
  59 }
  60
  61 static void i2c_hid_of_power_down(struct i2chid_ops *ops)
  62 {
  63         struct i2c_hid_of *ihid_of = container_of(ops, struct i2c_hid_of, ops);
  64
  65         regulator_bulk_disable(ARRAY_SIZE(ihid_of->supplies),
  66                                ihid_of->supplies);
  67 }
  68
  69 static int i2c_hid_of_probe(struct i2c_client *client,
  70                             const struct i2c_device_id *dev_id)
  71 {
  72         struct device *dev = &client->dev;
  73         struct i2c_hid_of *ihid_of;
  74         u16 hid_descriptor_address;
  75         u32 quirks = 0;
  76         int ret;
  77         u32 val;
  78
  79         ihid_of = devm_kzalloc(&client->dev, sizeof(*ihid_of), GFP_KERNEL);
  80         if (!ihid_of)
  81                 return -ENOMEM;
  82
  83         ihid_of->ops.power_up = i2c_hid_of_power_up;
  84         ihid_of->ops.power_down = i2c_hid_of_power_down;
  85
  86         ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
  87         if (ret) {
  88                 dev_err(&client->dev, "HID register address not provided\n");
  89                 return -ENODEV;
  90         }
  91         if (val >> 16) {
  92                 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
  93                         val);
  94                 return -EINVAL;
  95         }
  96         hid_descriptor_address = val;
  97
  98         if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
  99                                       &val))
 100                 ihid_of->post_power_delay_ms = val;
 101
 102         ihid_of->supplies[0].supply = "vdd";
 103         ihid_of->supplies[1].supply = "vddl";
 104         ret = devm_regulator_bulk_get(&client->dev,
 105                                       ARRAY_SIZE(ihid_of->supplies),
 106                                       ihid_of->supplies);
 107         if (ret)
 108                 return ret;
 109
 110         if (device_property_read_bool(dev, "touchscreen-inverted-x"))
 111                 quirks |= HID_QUIRK_X_INVERT;
 112
 113         if (device_property_read_bool(dev, "touchscreen-inverted-y"))
 114                 quirks |= HID_QUIRK_Y_INVERT;
 115
 116         return i2c_hid_core_probe(client, &ihid_of->ops,
 117                                   hid_descriptor_address, quirks);
 118 }
 119
 120 static const struct of_device_id i2c_hid_of_match[] = {
 121         { .compatible = "hid-over-i2c" },
 122         {},
 123 };
 124 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
 125
 126 static const struct i2c_device_id i2c_hid_of_id_table[] = {
 127         { "hid", 0 },
 128         { "hid-over-i2c", 0 },
 129         { },
 130 };
 131 MODULE_DEVICE_TABLE(i2c, i2c_hid_of_id_table);
 132
 133 static struct i2c_driver i2c_hid_of_driver = {
 134         .driver = {
 135                 .name   = "i2c_hid_of",
 136                 .pm     = &i2c_hid_core_pm,
 137                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 138                 .of_match_table = of_match_ptr(i2c_hid_of_match),
 139         },
 140
 141         .probe          = i2c_hid_of_probe,
 142         .remove         = i2c_hid_core_remove,
 143         .shutdown       = i2c_hid_core_shutdown,
 144         .id_table       = i2c_hid_of_id_table,
 145 };
 146
 147 module_i2c_driver(i2c_hid_of_driver);
 148
 149 MODULE_DESCRIPTION("HID over I2C OF driver");
 150 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
 151 MODULE_LICENSE("GPL");