drivers/hid/hid-picolcd_leds.c

   1 /***************************************************************************
   2  *   Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org>  *
   3  *                                                                         *
   4  *   Based on Logitech G13 driver (v0.4)                                   *
   5  *     Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu>   *
   6  *                                                                         *
   7  *   This program is free software: you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation, version 2 of the License.               *
  10  *                                                                         *
  11  *   This driver is distributed in the hope that it will be useful, but    *
  12  *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
  14  *   General Public License for more details.                              *
  15  *                                                                         *
  16  *   You should have received a copy of the GNU General Public License     *
  17  *   along with this software. If not see <http://www.gnu.org/licenses/>.  *
  18  ***************************************************************************/
  19
  20 #include <linux/hid.h>
  21 #include <linux/hid-debug.h>
  22 #include <linux/input.h>
  23 #include "hid-ids.h"
  24
  25 #include <linux/fb.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/backlight.h>
  28 #include <linux/lcd.h>
  29
  30 #include <linux/leds.h>
  31
  32 #include <linux/seq_file.h>
  33 #include <linux/debugfs.h>
  34
  35 #include <linux/completion.h>
  36 #include <linux/uaccess.h>
  37 #include <linux/module.h>
  38
  39 #include "hid-picolcd.h"
  40
  41
  42 void picolcd_leds_set(struct picolcd_data *data)
  43 {
  44         struct hid_report *report;
  45         unsigned long flags;
  46
  47         if (!data->led[0])
  48                 return;
  49         report = picolcd_out_report(REPORT_LED_STATE, data->hdev);
  50         if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
  51                 return;
  52
  53         spin_lock_irqsave(&data->lock, flags);
  54         hid_set_field(report->field[0], 0, data->led_state);
  55         if (!(data->status & PICOLCD_FAILED))
  56                 hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
  57         spin_unlock_irqrestore(&data->lock, flags);
  58 }
  59
  60 static void picolcd_led_set_brightness(struct led_classdev *led_cdev,
  61                         enum led_brightness value)
  62 {
  63         struct device *dev;
  64         struct hid_device *hdev;
  65         struct picolcd_data *data;
  66         int i, state = 0;
  67
  68         dev  = led_cdev->dev->parent;
  69         hdev = to_hid_device(dev);
  70         data = hid_get_drvdata(hdev);
  71         if (!data)
  72                 return;
  73         for (i = 0; i < 8; i++) {
  74                 if (led_cdev != data->led[i])
  75                         continue;
  76                 state = (data->led_state >> i) & 1;
  77                 if (value == LED_OFF && state) {
  78                         data->led_state &= ~(1 << i);
  79                         picolcd_leds_set(data);
  80                 } else if (value != LED_OFF && !state) {
  81                         data->led_state |= 1 << i;
  82                         picolcd_leds_set(data);
  83                 }
  84                 break;
  85         }
  86 }
  87
  88 static enum led_brightness picolcd_led_get_brightness(struct led_classdev *led_cdev)
  89 {
  90         struct device *dev;
  91         struct hid_device *hdev;
  92         struct picolcd_data *data;
  93         int i, value = 0;
  94
  95         dev  = led_cdev->dev->parent;
  96         hdev = to_hid_device(dev);
  97         data = hid_get_drvdata(hdev);
  98         for (i = 0; i < 8; i++)
  99                 if (led_cdev == data->led[i]) {
 100                         value = (data->led_state >> i) & 1;
 101                         break;
 102                 }
 103         return value ? LED_FULL : LED_OFF;
 104 }
 105
 106 int picolcd_init_leds(struct picolcd_data *data, struct hid_report *report)
 107 {
 108         struct device *dev = &data->hdev->dev;
 109         struct led_classdev *led;
 110         size_t name_sz = strlen(dev_name(dev)) + 8;
 111         char *name;
 112         int i, ret = 0;
 113
 114         if (!report)
 115                 return -ENODEV;
 116         if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
 117                         report->field[0]->report_size != 8) {
 118                 dev_err(dev, "unsupported LED_STATE report");
 119                 return -EINVAL;
 120         }
 121
 122         for (i = 0; i < 8; i++) {
 123                 led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
 124                 if (!led) {
 125                         dev_err(dev, "can't allocate memory for LED %d\n", i);
 126                         ret = -ENOMEM;
 127                         goto err;
 128                 }
 129                 name = (void *)(&led[1]);
 130                 snprintf(name, name_sz, "%s::GPO%d", dev_name(dev), i);
 131                 led->name = name;
 132                 led->brightness = 0;
 133                 led->max_brightness = 1;
 134                 led->brightness_get = picolcd_led_get_brightness;
 135                 led->brightness_set = picolcd_led_set_brightness;
 136
 137                 data->led[i] = led;
 138                 ret = led_classdev_register(dev, data->led[i]);
 139                 if (ret) {
 140                         data->led[i] = NULL;
 141                         kfree(led);
 142                         dev_err(dev, "can't register LED %d\n", i);
 143                         goto err;
 144                 }
 145         }
 146         return 0;
 147 err:
 148         for (i = 0; i < 8; i++)
 149                 if (data->led[i]) {
 150                         led = data->led[i];
 151                         data->led[i] = NULL;
 152                         led_classdev_unregister(led);
 153                         kfree(led);
 154                 }
 155         return ret;
 156 }
 157
 158 void picolcd_exit_leds(struct picolcd_data *data)
 159 {
 160         struct led_classdev *led;
 161         int i;
 162
 163         for (i = 0; i < 8; i++) {
 164                 led = data->led[i];
 165                 data->led[i] = NULL;
 166                 if (!led)
 167                         continue;
 168                 led_classdev_unregister(led);
 169                 kfree(led);
 170         }
 171 }
 172
 173