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/platform_device.h>
  18 #include <linux/leds.h>
  19 #include <linux/slab.h>
  20
  21 #include <linux/mfd/da9052/reg.h>
  22 #include <linux/mfd/da9052/da9052.h>
  23 #include <linux/mfd/da9052/pdata.h>
  24
  25 #define DA9052_OPENDRAIN_OUTPUT 2
  26 #define DA9052_SET_HIGH_LVL_OUTPUT      (1 << 3)
  27 #define DA9052_MASK_UPPER_NIBBLE        0xF0
  28 #define DA9052_MASK_LOWER_NIBBLE        0x0F
  29 #define DA9052_NIBBLE_SHIFT             4
  30 #define DA9052_MAX_BRIGHTNESS           0x5f
  31
  32 struct da9052_led {
  33         struct led_classdev cdev;
  34         struct da9052 *da9052;
  35         unsigned char led_index;
  36         unsigned char id;
  37 };
  38
  39 static unsigned char led_reg[] = {
  40         DA9052_LED_CONT_4_REG,
  41         DA9052_LED_CONT_5_REG,
  42 };
  43
  44 static int da9052_set_led_brightness(struct da9052_led *led,
  45                                      enum led_brightness brightness)
  46 {
  47         u8 val;
  48         int error;
  49
  50         val = (brightness & 0x7f) | DA9052_LED_CONT_DIM;
  51
  52         error = da9052_reg_write(led->da9052, led_reg[led->led_index], val);
  53         if (error < 0)
  54                 dev_err(led->da9052->dev, "Failed to set led brightness, %d\n",
  55                         error);
  56         return error;
  57 }
  58
  59 static int da9052_led_set(struct led_classdev *led_cdev,
  60                            enum led_brightness value)
  61 {
  62         struct da9052_led *led =
  63                         container_of(led_cdev, struct da9052_led, cdev);
  64
  65         return da9052_set_led_brightness(led, value);
  66 }
  67
  68 static int da9052_configure_leds(struct da9052 *da9052)
  69 {
  70         int error;
  71         unsigned char register_value = DA9052_OPENDRAIN_OUTPUT
  72                                        | DA9052_SET_HIGH_LVL_OUTPUT;
  73
  74         error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
  75                                   DA9052_MASK_LOWER_NIBBLE,
  76                                   register_value);
  77
  78         if (error < 0) {
  79                 dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
  80                         error);
  81                 return error;
  82         }
  83
  84         error = da9052_reg_update(da9052, DA9052_GPIO_14_15_REG,
  85                                   DA9052_MASK_UPPER_NIBBLE,
  86                                   register_value << DA9052_NIBBLE_SHIFT);
  87         if (error < 0)
  88                 dev_err(da9052->dev, "Failed to write GPIO 14-15 reg, %d\n",
  89                         error);
  90
  91         return error;
  92 }
  93
  94 static int da9052_led_probe(struct platform_device *pdev)
  95 {
  96         struct da9052_pdata *pdata;
  97         struct da9052 *da9052;
  98         struct led_platform_data *pled;
  99         struct da9052_led *led = NULL;
 100         int error = -ENODEV;
 101         int i;
 102
 103         da9052 = dev_get_drvdata(pdev->dev.parent);
 104         pdata = dev_get_platdata(da9052->dev);
 105         if (pdata == NULL) {
 106                 dev_err(&pdev->dev, "No platform data\n");
 107                 goto err;
 108         }
 109
 110         pled = pdata->pled;
 111         if (pled == NULL) {
 112                 dev_err(&pdev->dev, "No platform data for LED\n");
 113                 goto err;
 114         }
 115
 116         led = devm_kzalloc(&pdev->dev,
 117                            sizeof(struct da9052_led) * pled->num_leds,
 118                            GFP_KERNEL);
 119         if (!led) {
 120                 error = -ENOMEM;
 121                 goto err;
 122         }
 123
 124         for (i = 0; i < pled->num_leds; i++) {
 125                 led[i].cdev.name = pled->leds[i].name;
 126                 led[i].cdev.brightness_set_blocking = da9052_led_set;
 127                 led[i].cdev.brightness = LED_OFF;
 128                 led[i].cdev.max_brightness = DA9052_MAX_BRIGHTNESS;
 129                 led[i].led_index = pled->leds[i].flags;
 130                 led[i].da9052 = dev_get_drvdata(pdev->dev.parent);
 131
 132                 error = led_classdev_register(pdev->dev.parent, &led[i].cdev);
 133                 if (error) {
 134                         dev_err(&pdev->dev, "Failed to register led %d\n",
 135                                 led[i].led_index);
 136                         goto err_register;
 137                 }
 138
 139                 error = da9052_set_led_brightness(&led[i],
 140                                                   led[i].cdev.brightness);
 141                 if (error) {
 142                         dev_err(&pdev->dev, "Unable to init led %d\n",
 143                                 led[i].led_index);
 144                         continue;
 145                 }
 146         }
 147         error = da9052_configure_leds(led->da9052);
 148         if (error) {
 149                 dev_err(&pdev->dev, "Failed to configure GPIO LED%d\n", error);
 150                 goto err_register;
 151         }
 152
 153         platform_set_drvdata(pdev, led);
 154
 155         return 0;
 156
 157 err_register:
 158         for (i = i - 1; i >= 0; i--)
 159                 led_classdev_unregister(&led[i].cdev);
 160 err:
 161         return error;
 162 }
 163
 164 static int da9052_led_remove(struct platform_device *pdev)
 165 {
 166         struct da9052_led *led = platform_get_drvdata(pdev);
 167         struct da9052_pdata *pdata;
 168         struct da9052 *da9052;
 169         struct led_platform_data *pled;
 170         int i;
 171
 172         da9052 = dev_get_drvdata(pdev->dev.parent);
 173         pdata = dev_get_platdata(da9052->dev);
 174         pled = pdata->pled;
 175
 176         for (i = 0; i < pled->num_leds; i++) {
 177                 da9052_set_led_brightness(&led[i], LED_OFF);
 178                 led_classdev_unregister(&led[i].cdev);
 179         }
 180
 181         return 0;
 182 }
 183
 184 static struct platform_driver da9052_led_driver = {
 185         .driver         = {
 186                 .name   = "da9052-leds",
 187         },
 188         .probe          = da9052_led_probe,
 189         .remove         = da9052_led_remove,
 190 };
 191
 192 module_platform_driver(da9052_led_driver);
 193
 194 MODULE_AUTHOR("Dialog Semiconductor Ltd <dchen@diasemi.com>");
 195 MODULE_DESCRIPTION("LED driver for Dialog DA9052 PMIC");
 196 MODULE_LICENSE("GPL");