drivers/leds/leds-pm8058.c

   1 /* Copyright (c) 2010, 2011, 2016 The Linux Foundation. All rights reserved.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 and
   5  * only version 2 as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  */
  12 #include <linux/leds.h>
  13 #include <linux/module.h>
  14 #include <linux/of.h>
  15 #include <linux/of_device.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/pm.h>
  18 #include <linux/regmap.h>
  19
  20 #define PM8058_LED_TYPE_COMMON  0x00
  21 #define PM8058_LED_TYPE_KEYPAD  0x01
  22 #define PM8058_LED_TYPE_FLASH   0x02
  23
  24 #define PM8058_LED_TYPE_COMMON_MASK     0xf8
  25 #define PM8058_LED_TYPE_KEYPAD_MASK     0xf0
  26 #define PM8058_LED_TYPE_COMMON_SHIFT    3
  27 #define PM8058_LED_TYPE_KEYPAD_SHIFT    4
  28
  29 struct pm8058_led {
  30         struct regmap *map;
  31         u32 reg;
  32         u32 ledtype;
  33         struct led_classdev cdev;
  34 };
  35
  36 static void pm8058_led_set(struct led_classdev *cled,
  37         enum led_brightness value)
  38 {
  39         struct pm8058_led *led;
  40         int ret = 0;
  41         unsigned int mask = 0;
  42         unsigned int val = 0;
  43
  44         led = container_of(cled, struct pm8058_led, cdev);
  45         switch (led->ledtype) {
  46         case PM8058_LED_TYPE_COMMON:
  47                 mask = PM8058_LED_TYPE_COMMON_MASK;
  48                 val = value << PM8058_LED_TYPE_COMMON_SHIFT;
  49                 break;
  50         case PM8058_LED_TYPE_KEYPAD:
  51         case PM8058_LED_TYPE_FLASH:
  52                 mask = PM8058_LED_TYPE_KEYPAD_MASK;
  53                 val = value << PM8058_LED_TYPE_KEYPAD_SHIFT;
  54                 break;
  55         default:
  56                 break;
  57         }
  58
  59         ret = regmap_update_bits(led->map, led->reg, mask, val);
  60         if (ret)
  61                 pr_err("Failed to set LED brightness\n");
  62 }
  63
  64 static enum led_brightness pm8058_led_get(struct led_classdev *cled)
  65 {
  66         struct pm8058_led *led;
  67         int ret;
  68         unsigned int val;
  69
  70         led = container_of(cled, struct pm8058_led, cdev);
  71
  72         ret = regmap_read(led->map, led->reg, &val);
  73         if (ret) {
  74                 pr_err("Failed to get LED brightness\n");
  75                 return LED_OFF;
  76         }
  77
  78         switch (led->ledtype) {
  79         case PM8058_LED_TYPE_COMMON:
  80                 val &= PM8058_LED_TYPE_COMMON_MASK;
  81                 val >>= PM8058_LED_TYPE_COMMON_SHIFT;
  82                 break;
  83         case PM8058_LED_TYPE_KEYPAD:
  84         case PM8058_LED_TYPE_FLASH:
  85                 val &= PM8058_LED_TYPE_KEYPAD_MASK;
  86                 val >>= PM8058_LED_TYPE_KEYPAD_SHIFT;
  87                 break;
  88         default:
  89                 val = LED_OFF;
  90                 break;
  91         }
  92
  93         return val;
  94 }
  95
  96 static int pm8058_led_probe(struct platform_device *pdev)
  97 {
  98         struct pm8058_led *led;
  99         struct device_node *np = pdev->dev.of_node;
 100         int ret;
 101         struct regmap *map;
 102         const char *state;
 103         enum led_brightness maxbright;
 104
 105         led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
 106         if (!led)
 107                 return -ENOMEM;
 108
 109         led->ledtype = (u32)of_device_get_match_data(&pdev->dev);
 110
 111         map = dev_get_regmap(pdev->dev.parent, NULL);
 112         if (!map) {
 113                 dev_err(&pdev->dev, "Parent regmap unavailable.\n");
 114                 return -ENXIO;
 115         }
 116         led->map = map;
 117
 118         ret = of_property_read_u32(np, "reg", &led->reg);
 119         if (ret) {
 120                 dev_err(&pdev->dev, "no register offset specified\n");
 121                 return -EINVAL;
 122         }
 123
 124         /* Use label else node name */
 125         led->cdev.name = of_get_property(np, "label", NULL) ? : np->name;
 126         led->cdev.default_trigger =
 127                 of_get_property(np, "linux,default-trigger", NULL);
 128         led->cdev.brightness_set = pm8058_led_set;
 129         led->cdev.brightness_get = pm8058_led_get;
 130         if (led->ledtype == PM8058_LED_TYPE_COMMON)
 131                 maxbright = 31; /* 5 bits */
 132         else
 133                 maxbright = 15; /* 4 bits */
 134         led->cdev.max_brightness = maxbright;
 135
 136         state = of_get_property(np, "default-state", NULL);
 137         if (state) {
 138                 if (!strcmp(state, "keep")) {
 139                         led->cdev.brightness = pm8058_led_get(&led->cdev);
 140                 } else if (!strcmp(state, "on")) {
 141                         led->cdev.brightness = maxbright;
 142                         pm8058_led_set(&led->cdev, maxbright);
 143                 } else {
 144                         led->cdev.brightness = LED_OFF;
 145                         pm8058_led_set(&led->cdev, LED_OFF);
 146                 }
 147         }
 148
 149         if (led->ledtype == PM8058_LED_TYPE_KEYPAD ||
 150             led->ledtype == PM8058_LED_TYPE_FLASH)
 151                 led->cdev.flags = LED_CORE_SUSPENDRESUME;
 152
 153         ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
 154         if (ret) {
 155                 dev_err(&pdev->dev, "unable to register led \"%s\"\n",
 156                         led->cdev.name);
 157                 return ret;
 158         }
 159
 160         return 0;
 161 }
 162
 163 static const struct of_device_id pm8058_leds_id_table[] = {
 164         {
 165                 .compatible = "qcom,pm8058-led",
 166                 .data = (void *)PM8058_LED_TYPE_COMMON
 167         },
 168         {
 169                 .compatible = "qcom,pm8058-keypad-led",
 170                 .data = (void *)PM8058_LED_TYPE_KEYPAD
 171         },
 172         {
 173                 .compatible = "qcom,pm8058-flash-led",
 174                 .data = (void *)PM8058_LED_TYPE_FLASH
 175         },
 176         { },
 177 };
 178 MODULE_DEVICE_TABLE(of, pm8058_leds_id_table);
 179
 180 static struct platform_driver pm8058_led_driver = {
 181         .probe          = pm8058_led_probe,
 182         .driver         = {
 183                 .name   = "pm8058-leds",
 184                 .of_match_table = pm8058_leds_id_table,
 185         },
 186 };
 187 module_platform_driver(pm8058_led_driver);
 188
 189 MODULE_DESCRIPTION("PM8058 LEDs driver");
 190 MODULE_LICENSE("GPL v2");
 191 MODULE_ALIAS("platform:pm8058-leds");