target/linux/mediatek/files/drivers/leds/leds-ubnt-ledbar.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include <linux/delay.h>
   4 #include <linux/i2c.h>
   5 #include <linux/init.h>
   6 #include <linux/leds.h>
   7 #include <linux/module.h>
   8 #include <linux/mutex.h>
   9 #include <linux/of.h>
  10 #include <linux/of_gpio.h>
  11 #include <linux/gpio/consumer.h>
  12
  13 /**
  14  * Driver for the Ubiquiti RGB LED controller (LEDBAR).
  15  * This Controller is based on a Holtek HT32F52241 and connected
  16  * via I2C.
  17  *
  18  *  - The Controller needs an enable signal set to high when
  19  *    performing a transaction. On the U6-LR, this is located
  20  *    at Pin 18 (R6902)
  21  *
  22  *  - The Pin is also printed when calling the "usetled" function
  23  *    contained in the ubntapp bootloader application.
  24  */
  25
  26 #define UBNT_LEDBAR_MAX_BRIGHTNESS      0xff
  27
  28 #define UBNT_LEDBAR_TRANSACTION_LENGTH  8
  29 #define UBNT_LEDBAR_TRANSACTION_SUCCESS 0xaa
  30
  31 #define UBNT_LEDBAR_TRANSACTION_BLUE_IDX        2
  32 #define UBNT_LEDBAR_TRANSACTION_GREEN_IDX       3
  33 #define UBNT_LEDBAR_TRANSACTION_RED_IDX         4
  34
  35 struct ubnt_ledbar {
  36         struct mutex lock;
  37         struct i2c_client *client;
  38         struct led_classdev led_red;
  39         struct led_classdev led_green;
  40         struct led_classdev led_blue;
  41         struct gpio_desc *enable_gpio;
  42 };
  43
  44 static int ubnt_ledbar_perform_transaction(struct ubnt_ledbar *ledbar,
  45                                            char *transaction)
  46 {
  47         int ret;
  48         int i;
  49
  50         for (i = 0; i < UBNT_LEDBAR_TRANSACTION_LENGTH; i++)
  51                 i2c_smbus_write_byte(ledbar->client, transaction[i]);
  52
  53         return i2c_smbus_read_byte(ledbar->client);
  54 }
  55
  56 static int ubnt_ledbar_apply_state(struct ubnt_ledbar *ledbar)
  57 {
  58         char setup_msg[UBNT_LEDBAR_TRANSACTION_LENGTH] = {0x40, 0x10, 0x00, 0x00,
  59                                                           0x00, 0x00, 0x00, 0x11};
  60         char led_msg[UBNT_LEDBAR_TRANSACTION_LENGTH] = {0x40, 0x00, 0x00, 0x00,
  61                                                         0x00, 0x00, 0x01, 0x00};
  62         char i2c_response;
  63         int ret = 0;
  64
  65         mutex_lock(&ledbar->lock);
  66
  67         led_msg[UBNT_LEDBAR_TRANSACTION_BLUE_IDX] = ledbar->led_blue.brightness;
  68         led_msg[UBNT_LEDBAR_TRANSACTION_GREEN_IDX] = ledbar->led_green.brightness;
  69         led_msg[UBNT_LEDBAR_TRANSACTION_RED_IDX] = ledbar->led_red.brightness;
  70
  71         gpiod_set_raw_value(ledbar->enable_gpio, 1);
  72
  73         msleep(10);
  74
  75         i2c_response = ubnt_ledbar_perform_transaction(ledbar, setup_msg);
  76         if (i2c_response != UBNT_LEDBAR_TRANSACTION_SUCCESS) {
  77                 dev_err(&ledbar->client->dev, "Error initializing LED transaction: %02x\n", ret);
  78                 ret = -EINVAL;
  79                 goto out_gpio;
  80         }
  81
  82         i2c_response = ubnt_ledbar_perform_transaction(ledbar, led_msg);
  83         if (i2c_response != UBNT_LEDBAR_TRANSACTION_SUCCESS) {
  84                 dev_err(&ledbar->client->dev, "Failed LED transaction: %02x\n", ret);
  85                 ret = -EINVAL;
  86                 goto out_gpio;
  87         }
  88
  89         msleep(10);
  90 out_gpio:
  91         gpiod_set_raw_value(ledbar->enable_gpio, 0);
  92
  93         mutex_unlock(&ledbar->lock);
  94
  95         return ret;
  96 }
  97
  98 #define UBNT_LEDBAR_CONTROL_RGBS(name)                          \
  99 static int ubnt_ledbar_set_##name##_brightness(struct led_classdev *led_cdev,\
 100                                         enum led_brightness value)      \
 101 {                                                                       \
 102         struct ubnt_ledbar *ledbar = \
 103                         container_of(led_cdev, struct ubnt_ledbar, led_##name); \
 104         int ret; \
 105         led_cdev->brightness = value; \
 106         ret = ubnt_ledbar_apply_state(ledbar); \
 107         return ret; \
 108 }
 109
 110 UBNT_LEDBAR_CONTROL_RGBS(red);
 111 UBNT_LEDBAR_CONTROL_RGBS(green);
 112 UBNT_LEDBAR_CONTROL_RGBS(blue);
 113
 114
 115 static int ubnt_ledbar_init_led(struct device_node *np, struct ubnt_ledbar *ledbar,
 116                                 struct led_classdev *led_cdev)
 117 {
 118         struct led_init_data init_data = {};
 119         int ret;
 120
 121         if (!np)
 122                 return 0;
 123
 124         init_data.fwnode = of_fwnode_handle(np);
 125
 126         led_cdev->max_brightness = UBNT_LEDBAR_MAX_BRIGHTNESS;
 127
 128         ret = devm_led_classdev_register_ext(&ledbar->client->dev, led_cdev,
 129                                              &init_data);
 130         if (ret)
 131                 dev_err(&ledbar->client->dev, "led register err: %d\n", ret);
 132
 133         return ret;
 134 }
 135
 136
 137 static int ubnt_ledbar_probe(struct i2c_client *client,
 138                              const struct i2c_device_id *id)
 139 {
 140         struct device_node *np = client->dev.of_node;
 141         struct ubnt_ledbar *ledbar;
 142         int ret;
 143
 144         ledbar = devm_kzalloc(&client->dev, sizeof(*ledbar), GFP_KERNEL);
 145         if (!ledbar)
 146                 return -ENOMEM;
 147
 148         ledbar->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_LOW);
 149
 150         if (IS_ERR(ledbar->enable_gpio)) {
 151                 ret = PTR_ERR(ledbar->enable_gpio);
 152                 dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
 153                 return ret;
 154         }
 155
 156         gpiod_direction_output(ledbar->enable_gpio, 0);
 157
 158         ledbar->client = client;
 159
 160         mutex_init(&ledbar->lock);
 161
 162         i2c_set_clientdata(client, ledbar);
 163
 164         ledbar->led_red.brightness_set_blocking = ubnt_ledbar_set_red_brightness;
 165         ubnt_ledbar_init_led(of_get_child_by_name(np, "red"), ledbar, &ledbar->led_red);
 166
 167         ledbar->led_green.brightness_set_blocking = ubnt_ledbar_set_green_brightness;
 168         ubnt_ledbar_init_led(of_get_child_by_name(np, "green"), ledbar, &ledbar->led_green);
 169
 170         ledbar->led_blue.brightness_set_blocking = ubnt_ledbar_set_blue_brightness;
 171         ubnt_ledbar_init_led(of_get_child_by_name(np, "blue"), ledbar, &ledbar->led_blue);
 172
 173         return ubnt_ledbar_apply_state(ledbar);
 174 }
 175
 176 static int ubnt_ledbar_remove(struct i2c_client *client)
 177 {
 178         struct ubnt_ledbar *ledbar = i2c_get_clientdata(client);
 179
 180         mutex_destroy(&ledbar->lock);
 181
 182         return 0;
 183 }
 184
 185 static const struct i2c_device_id ubnt_ledbar_id[] = {
 186         { "ubnt-ledbar", 0 },
 187         { }
 188 };
 189 MODULE_DEVICE_TABLE(i2c, ubnt_ledbar_id);
 190
 191 static const struct of_device_id of_ubnt_ledbar_match[] = {
 192         { .compatible = "ubnt,ledbar", },
 193         {},
 194 };
 195 MODULE_DEVICE_TABLE(of, of_ubnt_ledbar_match);
 196
 197 static struct i2c_driver ubnt_ledbar_driver = {
 198         .driver = {
 199                 .name   = "ubnt-ledbar",
 200                 .of_match_table = of_ubnt_ledbar_match,
 201         },
 202         .probe          = ubnt_ledbar_probe,
 203         .remove         = ubnt_ledbar_remove,
 204         .id_table       = ubnt_ledbar_id,
 205 };
 206 module_i2c_driver(ubnt_ledbar_driver);
 207
 208 MODULE_DESCRIPTION("Ubiquiti LEDBAR driver");
 209 MODULE_AUTHOR("David Bauer <mail@david-bauer.net>");
 210 MODULE_LICENSE("GPL v2");