drivers/leds/leds-tlc591xx.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2014 Belkin Inc.
   4  * Copyright 2015 Andrew Lunn <andrew@lunn.ch>
   5  */
   6
   7 #include <linux/i2c.h>
   8 #include <linux/leds.h>
   9 #include <linux/module.h>
  10 #include <linux/of.h>
  11 #include <linux/of_device.h>
  12 #include <linux/regmap.h>
  13 #include <linux/slab.h>
  14
  15 #define TLC591XX_MAX_LEDS       16
  16
  17 #define TLC591XX_REG_MODE1      0x00
  18 #define MODE1_RESPON_ADDR_MASK  0xF0
  19 #define MODE1_NORMAL_MODE       (0 << 4)
  20 #define MODE1_SPEED_MODE        (1 << 4)
  21
  22 #define TLC591XX_REG_MODE2      0x01
  23 #define MODE2_DIM               (0 << 5)
  24 #define MODE2_BLINK             (1 << 5)
  25 #define MODE2_OCH_STOP          (0 << 3)
  26 #define MODE2_OCH_ACK           (1 << 3)
  27
  28 #define TLC591XX_REG_PWM(x)     (0x02 + (x))
  29
  30 #define TLC591XX_REG_GRPPWM     0x12
  31 #define TLC591XX_REG_GRPFREQ    0x13
  32
  33 /* LED Driver Output State, determine the source that drives LED outputs */
  34 #define LEDOUT_OFF              0x0     /* Output LOW */
  35 #define LEDOUT_ON               0x1     /* Output HI-Z */
  36 #define LEDOUT_DIM              0x2     /* Dimming */
  37 #define LEDOUT_BLINK            0x3     /* Blinking */
  38 #define LEDOUT_MASK             0x3
  39
  40 #define ldev_to_led(c)          container_of(c, struct tlc591xx_led, ldev)
  41
  42 struct tlc591xx_led {
  43         bool active;
  44         unsigned int led_no;
  45         struct led_classdev ldev;
  46         struct tlc591xx_priv *priv;
  47 };
  48
  49 struct tlc591xx_priv {
  50         struct tlc591xx_led leds[TLC591XX_MAX_LEDS];
  51         struct regmap *regmap;
  52         unsigned int reg_ledout_offset;
  53 };
  54
  55 struct tlc591xx {
  56         unsigned int max_leds;
  57         unsigned int reg_ledout_offset;
  58 };
  59
  60 static const struct tlc591xx tlc59116 = {
  61         .max_leds = 16,
  62         .reg_ledout_offset = 0x14,
  63 };
  64
  65 static const struct tlc591xx tlc59108 = {
  66         .max_leds = 8,
  67         .reg_ledout_offset = 0x0c,
  68 };
  69
  70 static int
  71 tlc591xx_set_mode(struct regmap *regmap, u8 mode)
  72 {
  73         int err;
  74         u8 val;
  75
  76         err = regmap_write(regmap, TLC591XX_REG_MODE1, MODE1_NORMAL_MODE);
  77         if (err)
  78                 return err;
  79
  80         val = MODE2_OCH_STOP | mode;
  81
  82         return regmap_write(regmap, TLC591XX_REG_MODE2, val);
  83 }
  84
  85 static int
  86 tlc591xx_set_ledout(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
  87                     u8 val)
  88 {
  89         unsigned int i = (led->led_no % 4) * 2;
  90         unsigned int mask = LEDOUT_MASK << i;
  91         unsigned int addr = priv->reg_ledout_offset + (led->led_no >> 2);
  92
  93         val = val << i;
  94
  95         return regmap_update_bits(priv->regmap, addr, mask, val);
  96 }
  97
  98 static int
  99 tlc591xx_set_pwm(struct tlc591xx_priv *priv, struct tlc591xx_led *led,
 100                  u8 brightness)
 101 {
 102         u8 pwm = TLC591XX_REG_PWM(led->led_no);
 103
 104         return regmap_write(priv->regmap, pwm, brightness);
 105 }
 106
 107 static int
 108 tlc591xx_brightness_set(struct led_classdev *led_cdev,
 109                         enum led_brightness brightness)
 110 {
 111         struct tlc591xx_led *led = ldev_to_led(led_cdev);
 112         struct tlc591xx_priv *priv = led->priv;
 113         int err;
 114
 115         switch (brightness) {
 116         case 0:
 117                 err = tlc591xx_set_ledout(priv, led, LEDOUT_OFF);
 118                 break;
 119         case LED_FULL:
 120                 err = tlc591xx_set_ledout(priv, led, LEDOUT_ON);
 121                 break;
 122         default:
 123                 err = tlc591xx_set_ledout(priv, led, LEDOUT_DIM);
 124                 if (!err)
 125                         err = tlc591xx_set_pwm(priv, led, brightness);
 126         }
 127
 128         return err;
 129 }
 130
 131 static void
 132 tlc591xx_destroy_devices(struct tlc591xx_priv *priv, unsigned int j)
 133 {
 134         int i = j;
 135
 136         while (--i >= 0) {
 137                 if (priv->leds[i].active)
 138                         led_classdev_unregister(&priv->leds[i].ldev);
 139         }
 140 }
 141
 142 static int
 143 tlc591xx_configure(struct device *dev,
 144                    struct tlc591xx_priv *priv,
 145                    const struct tlc591xx *tlc591xx)
 146 {
 147         unsigned int i;
 148         int err = 0;
 149
 150         tlc591xx_set_mode(priv->regmap, MODE2_DIM);
 151         for (i = 0; i < TLC591XX_MAX_LEDS; i++) {
 152                 struct tlc591xx_led *led = &priv->leds[i];
 153
 154                 if (!led->active)
 155                         continue;
 156
 157                 led->priv = priv;
 158                 led->led_no = i;
 159                 led->ldev.brightness_set_blocking = tlc591xx_brightness_set;
 160                 led->ldev.max_brightness = LED_FULL;
 161                 err = led_classdev_register(dev, &led->ldev);
 162                 if (err < 0) {
 163                         dev_err(dev, "couldn't register LED %s\n",
 164                                 led->ldev.name);
 165                         goto exit;
 166                 }
 167         }
 168
 169         return 0;
 170
 171 exit:
 172         tlc591xx_destroy_devices(priv, i);
 173         return err;
 174 }
 175
 176 static const struct regmap_config tlc591xx_regmap = {
 177         .reg_bits = 8,
 178         .val_bits = 8,
 179         .max_register = 0x1e,
 180 };
 181
 182 static const struct of_device_id of_tlc591xx_leds_match[] = {
 183         { .compatible = "ti,tlc59116",
 184           .data = &tlc59116 },
 185         { .compatible = "ti,tlc59108",
 186           .data = &tlc59108 },
 187         {},
 188 };
 189 MODULE_DEVICE_TABLE(of, of_tlc591xx_leds_match);
 190
 191 static int
 192 tlc591xx_probe(struct i2c_client *client,
 193                const struct i2c_device_id *id)
 194 {
 195         struct device_node *np = client->dev.of_node, *child;
 196         struct device *dev = &client->dev;
 197         const struct of_device_id *match;
 198         const struct tlc591xx *tlc591xx;
 199         struct tlc591xx_priv *priv;
 200         int err, count, reg;
 201
 202         match = of_match_device(of_tlc591xx_leds_match, dev);
 203         if (!match)
 204                 return -ENODEV;
 205
 206         tlc591xx = match->data;
 207         if (!np)
 208                 return -ENODEV;
 209
 210         count = of_get_child_count(np);
 211         if (!count || count > tlc591xx->max_leds)
 212                 return -EINVAL;
 213
 214         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 215         if (!priv)
 216                 return -ENOMEM;
 217
 218         priv->regmap = devm_regmap_init_i2c(client, &tlc591xx_regmap);
 219         if (IS_ERR(priv->regmap)) {
 220                 err = PTR_ERR(priv->regmap);
 221                 dev_err(dev, "Failed to allocate register map: %d\n", err);
 222                 return err;
 223         }
 224         priv->reg_ledout_offset = tlc591xx->reg_ledout_offset;
 225
 226         i2c_set_clientdata(client, priv);
 227
 228         for_each_child_of_node(np, child) {
 229                 err = of_property_read_u32(child, "reg", &reg);
 230                 if (err) {
 231                         of_node_put(child);
 232                         return err;
 233                 }
 234                 if (reg < 0 || reg >= tlc591xx->max_leds ||
 235                     priv->leds[reg].active) {
 236                         of_node_put(child);
 237                         return -EINVAL;
 238                 }
 239                 priv->leds[reg].active = true;
 240                 priv->leds[reg].ldev.name =
 241                         of_get_property(child, "label", NULL) ? : child->name;
 242                 priv->leds[reg].ldev.default_trigger =
 243                         of_get_property(child, "linux,default-trigger", NULL);
 244         }
 245         return tlc591xx_configure(dev, priv, tlc591xx);
 246 }
 247
 248 static int
 249 tlc591xx_remove(struct i2c_client *client)
 250 {
 251         struct tlc591xx_priv *priv = i2c_get_clientdata(client);
 252
 253         tlc591xx_destroy_devices(priv, TLC591XX_MAX_LEDS);
 254
 255         return 0;
 256 }
 257
 258 static const struct i2c_device_id tlc591xx_id[] = {
 259         { "tlc59116" },
 260         { "tlc59108" },
 261         {},
 262 };
 263 MODULE_DEVICE_TABLE(i2c, tlc591xx_id);
 264
 265 static struct i2c_driver tlc591xx_driver = {
 266         .driver = {
 267                 .name = "tlc591xx",
 268                 .of_match_table = of_match_ptr(of_tlc591xx_leds_match),
 269         },
 270         .probe = tlc591xx_probe,
 271         .remove = tlc591xx_remove,
 272         .id_table = tlc591xx_id,
 273 };
 274
 275 module_i2c_driver(tlc591xx_driver);
 276
 277 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
 278 MODULE_LICENSE("GPL");
 279 MODULE_DESCRIPTION("TLC591XX LED driver");