drivers/leds/leds-da9052.c

   1 /*
   2  * LED Driver for Dialog DA9052 PMICs.
   3  *
   4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
   5  *
   6  * Author: David Dajun Chen <dchen@diasemi.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/leds.h>
  20 #include <linux/workqueue.h>
  21 #include <linux/slab.h>
  22
  23 #include <linux/mfd/da9052/reg.h>
  24 #include <linux/mfd/da9052/da9052.h>
  25 #include <linux/mfd/da9052/pdata.h>
  26
  27 #define DA9052_OPENDRAIN_OUTPUT 2
  28 #define DA9052_SET_HIGH_LVL_OUTPUT      (1 << 3)
  29 #define DA9052_MASK_UPPER_NIBBLE        0xF0
  30 #define DA9052_MASK_LOWER_NIBBLE        0x0F
  31 #define DA9052_NIBBLE_SHIFT             4
  32 #define DA9052_MAX_BRIGHTNESS           0x5f
  33
  34 struct da9052_led {
  35         struct led_classdev cdev;
  36         struct work_struct work;
  37         struct da9052 *da9052;
  38         unsigned char led_index;
  39         unsigned char id;
  40         int brightness;
  41 };
  42
  43 static unsigned char led_reg[] = {
  44         DA9052_LED_CONT_4_REG,
  45         DA9052_LED_CONT_5_REG,
  46 };
  47
  48 static int da9052_set_led_brightness(struct da9052_led *led)
  49 {
  50         u8 val;
  51         int error;
  52
  53         val = (led->brightness & 0x7f) | DA9052_LED_CONT_DIM;
  54
  55         error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
  56         if (error < 0)
  57                 dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
  58                         error);
  59         return error;
  60 }
  61
  62 static void da9052_led_work(struct work_struct *work)
  63 {
  64         struct da9052_led *led = container_of(work, struct da9052_led, work);
  65
  66         da9052_set_led_brightness(led);
  67 }
  68
  69 static void da9052_led_set(struct led_classdev *led_cdev,
  70                            enum led_brightness value)
  71 {
  72         struct da9052_led *led;
  73
  74         led = container_of(led_cdev, struct da9052_led, cdev);
  75         led->brightness = value;
  76         schedule_work(&led->work);
  77 }
  78
  79 static int da9052_configure_leds(struct da9052 *da9052)
  80 {
  81         int error;
  82         unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
  83                                        | DA9052_SET_HIGH_LVL_OUTPUT;
  84
  85         error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
  86                                   DA9052_MASK_LOWER_NIBBLE,
  87                                   register_value);
  88
  89         if (error < 0) {
  90                 dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
  91                         error);
  92                 return error;
  93         }
  94
  95         error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
  96                                   DA9052_MASK_UPPER_NIBBLE,
  97                                   register_value << DA9052_NIBBLE_SHIFT);
  98         if (error < 0)
  99                 dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
 100                         error);
 101
 102         return error;
 103 }
 104
 105 static int da9052_led_probe(struct platform_device *pdev)
 106 {
 107         struct da9052_pdata *pdata;
 108         struct da9052 *da9052;
 109         struct led_platform_data *pled;
 110         struct da9052_led *led = NULL;
 111         int error = -ENODEV;
 112         int i;
 113
 114         da9052 = dev_get_drvdata(pdev->dev.parent);
 115         pdata = da9052->dev->platform_data;
 116         if (pdata == NULL) {
 117                 dev_err(&pdev->dev, "No platform data\n");
 118                 goto err;
 119         }
 120
 121         pled = pdata->pled;
 122         if (pled == NULL) {
 123                 dev_err(&pdev->dev, "No platform data for LED\n");
 124                 goto err;
 125         }
 126
 127         led = devm_kzalloc(&pdev->dev,
 128                            sizeof(struct da9052_led) * pled->num_leds,
 129                            GFP_KERNEL);
 130         if (led == NULL) {
 131                 dev_err(&pdev->dev, "Failed to alloc memory\n");
 132                 error = -ENOMEM;
 133                 goto err;
 134         }
 135
 136         for (i = 0; i < pled->num_leds; i++) {
 137                 led[i].cdev.name = pled->leds[i].name;
 138                 led[i].cdev.brightness_set = da9052_led_set;
 139                 led[i].cdev.brightness = LED_OFF;
 140                 led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
 141                 led[i].brightness = LED_OFF;
 142                 led[i].led_index = pled->leds[i].flags;
 143                 led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
 144                 INIT_WORK(&led[i].work, da9052_led_work);
 145
 146                 error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
 147                 if (error) {
 148                         dev_err(&pdev->dev, "Failed to register led %d\n",
 149                                 led[i].led_index);
 150                         goto err_register;
 151                 }
 152
 153                 error = da9052_set_led_brightness(&led[i]);
 154                 if (error) {
 155                         dev_err(&pdev->dev, "Unable to init led %d\n",
 156                                 led[i].led_index);
 157                         continue;
 158                 }
 159         }
 160         error = da9052_configure_leds(led->da9052);
 161         if (error) {
 162                 dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
 163                 goto err_register;
 164         }
 165
 166         platform_set_drvdata(pdev, led);
 167
 168         return 0;
 169
 170 err_register:
 171         for (i = i - 1; i >= 0; i--) {
 172                 led_classdev_unregister(&led[i].cdev);
 173                 cancel_work_sync(&led[i].work);
 174         }
 175 err:
 176         return error;
 177 }
 178
 179 static int da9052_led_remove(struct platform_device *pdev)
 180 {
 181         struct da9052_led *led = platform_get_drvdata(pdev);
 182         struct da9052_pdata *pdata;
 183         struct da9052 *da9052;
 184         struct led_platform_data *pled;
 185         int i;
 186
 187         da9052 = dev_get_drvdata(pdev->dev.parent);
 188         pdata = da9052->dev->platform_data;
 189         pled = pdata->pled;
 190
 191         for (i = 0; i < pled->num_leds; i++) {
 192                 led[i].brightness = 0;
 193                 da9052_set_led_brightness(&led[i]);
 194                 led_classdev_unregister(&led[i].cdev);
 195                 cancel_work_sync(&led[i].work);
 196         }
 197
 198         return 0;
 199 }
 200
 201 static struct platform_driver da9052_led_driver = {
 202         .driver         = {
 203                 .name   = "da9052-leds",
 204                 .owner  = THIS_MODULE,
 205         },
 206         .probe          = da9052_led_probe,
 207         .remove         = da9052_led_remove,
 208 };
 209
 210 module_platform_driver(da9052_led_driver);
 211
 212 MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
 213 MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
 214 MODULE_LICENSE("GPL");