drivers/video/backlight/bd6107.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * ROHM Semiconductor BD6107 LED Driver
   4  *
   5  * Copyright (C) 2013 Ideas on board SPRL
   6  *
   7  * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
   8  */
   9
  10 #include <linux/backlight.h>
  11 #include <linux/delay.h>
  12 #include <linux/err.h>
  13 #include <linux/fb.h>
  14 #include <linux/gpio/consumer.h>
  15 #include <linux/i2c.h>
  16 #include <linux/module.h>
  17 #include <linux/platform_data/bd6107.h>
  18 #include <linux/slab.h>
  19
  20 #define BD6107_PSCNT1                           0x00
  21 #define BD6107_PSCNT1_PSCNTREG2                 (1 << 2)
  22 #define BD6107_PSCNT1_PSCNTREG1                 (1 << 0)
  23 #define BD6107_REGVSET                          0x02
  24 #define BD6107_REGVSET_REG1VSET_2_85V           (1 << 2)
  25 #define BD6107_REGVSET_REG1VSET_2_80V           (0 << 2)
  26 #define BD6107_LEDCNT1                          0x03
  27 #define BD6107_LEDCNT1_LEDONOFF2                (1 << 1)
  28 #define BD6107_LEDCNT1_LEDONOFF1                (1 << 0)
  29 #define BD6107_PORTSEL                          0x04
  30 #define BD6107_PORTSEL_LEDM(n)                  (1 << (n))
  31 #define BD6107_RGB1CNT1                         0x05
  32 #define BD6107_RGB1CNT2                         0x06
  33 #define BD6107_RGB1CNT3                         0x07
  34 #define BD6107_RGB1CNT4                         0x08
  35 #define BD6107_RGB1CNT5                         0x09
  36 #define BD6107_RGB1FLM                          0x0a
  37 #define BD6107_RGB2CNT1                         0x0b
  38 #define BD6107_RGB2CNT2                         0x0c
  39 #define BD6107_RGB2CNT3                         0x0d
  40 #define BD6107_RGB2CNT4                         0x0e
  41 #define BD6107_RGB2CNT5                         0x0f
  42 #define BD6107_RGB2FLM                          0x10
  43 #define BD6107_PSCONT3                          0x11
  44 #define BD6107_SMMONCNT                         0x12
  45 #define BD6107_DCDCCNT                          0x13
  46 #define BD6107_IOSEL                            0x14
  47 #define BD6107_OUT1                             0x15
  48 #define BD6107_OUT2                             0x16
  49 #define BD6107_MASK1                            0x17
  50 #define BD6107_MASK2                            0x18
  51 #define BD6107_FACTOR1                          0x19
  52 #define BD6107_FACTOR2                          0x1a
  53 #define BD6107_CLRFACT1                         0x1b
  54 #define BD6107_CLRFACT2                         0x1c
  55 #define BD6107_STATE1                           0x1d
  56 #define BD6107_LSIVER                           0x1e
  57 #define BD6107_GRPSEL                           0x1f
  58 #define BD6107_LEDCNT2                          0x20
  59 #define BD6107_LEDCNT3                          0x21
  60 #define BD6107_MCURRENT                         0x22
  61 #define BD6107_MAINCNT1                         0x23
  62 #define BD6107_MAINCNT2                         0x24
  63 #define BD6107_SLOPECNT                         0x25
  64 #define BD6107_MSLOPE                           0x26
  65 #define BD6107_RGBSLOPE                         0x27
  66 #define BD6107_TEST                             0x29
  67 #define BD6107_SFTRST                           0x2a
  68 #define BD6107_SFTRSTGD                         0x2b
  69
  70 struct bd6107 {
  71         struct i2c_client *client;
  72         struct backlight_device *backlight;
  73         struct bd6107_platform_data *pdata;
  74         struct gpio_desc *reset;
  75 };
  76
  77 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data)
  78 {
  79         return i2c_smbus_write_byte_data(bd->client, reg, data);
  80 }
  81
  82 static int bd6107_backlight_update_status(struct backlight_device *backlight)
  83 {
  84         struct bd6107 *bd = bl_get_data(backlight);
  85         int brightness = backlight_get_brightness(backlight);
  86
  87         if (brightness) {
  88                 bd6107_write(bd, BD6107_PORTSEL, BD6107_PORTSEL_LEDM(2) |
  89                              BD6107_PORTSEL_LEDM(1) | BD6107_PORTSEL_LEDM(0));
  90                 bd6107_write(bd, BD6107_MAINCNT1, brightness);
  91                 bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1);
  92         } else {
  93                 /* Assert the reset line (gpiolib will handle active low) */
  94                 gpiod_set_value(bd->reset, 1);
  95                 msleep(24);
  96                 gpiod_set_value(bd->reset, 0);
  97         }
  98
  99         return 0;
 100 }
 101
 102 static int bd6107_backlight_check_fb(struct backlight_device *backlight,
 103                                        struct fb_info *info)
 104 {
 105         struct bd6107 *bd = bl_get_data(backlight);
 106
 107         return bd->pdata->fbdev == NULL || bd->pdata->fbdev == info->dev;
 108 }
 109
 110 static const struct backlight_ops bd6107_backlight_ops = {
 111         .options        = BL_CORE_SUSPENDRESUME,
 112         .update_status  = bd6107_backlight_update_status,
 113         .check_fb       = bd6107_backlight_check_fb,
 114 };
 115
 116 static int bd6107_probe(struct i2c_client *client,
 117                           const struct i2c_device_id *id)
 118 {
 119         struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev);
 120         struct backlight_device *backlight;
 121         struct backlight_properties props;
 122         struct bd6107 *bd;
 123         int ret;
 124
 125         if (pdata == NULL) {
 126                 dev_err(&client->dev, "No platform data\n");
 127                 return -EINVAL;
 128         }
 129
 130         if (!i2c_check_functionality(client->adapter,
 131                                      I2C_FUNC_SMBUS_BYTE_DATA)) {
 132                 dev_warn(&client->dev,
 133                          "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
 134                 return -EIO;
 135         }
 136
 137         bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL);
 138         if (!bd)
 139                 return -ENOMEM;
 140
 141         bd->client = client;
 142         bd->pdata = pdata;
 143
 144         /*
 145          * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted,
 146          * so in the machine descriptor table (or other hardware description),
 147          * the line should be flagged as active low so this will assert
 148          * the reset.
 149          */
 150         bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
 151         if (IS_ERR(bd->reset)) {
 152                 dev_err(&client->dev, "unable to request reset GPIO\n");
 153                 ret = PTR_ERR(bd->reset);
 154                 return ret;
 155         }
 156
 157         memset(&props, 0, sizeof(props));
 158         props.type = BACKLIGHT_RAW;
 159         props.max_brightness = 128;
 160         props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
 161                                    props.max_brightness);
 162
 163         backlight = devm_backlight_device_register(&client->dev,
 164                                               dev_name(&client->dev),
 165                                               &bd->client->dev, bd,
 166                                               &bd6107_backlight_ops, &props);
 167         if (IS_ERR(backlight)) {
 168                 dev_err(&client->dev, "failed to register backlight\n");
 169                 return PTR_ERR(backlight);
 170         }
 171
 172         backlight_update_status(backlight);
 173         i2c_set_clientdata(client, backlight);
 174
 175         return 0;
 176 }
 177
 178 static int bd6107_remove(struct i2c_client *client)
 179 {
 180         struct backlight_device *backlight = i2c_get_clientdata(client);
 181
 182         backlight->props.brightness = 0;
 183         backlight_update_status(backlight);
 184
 185         return 0;
 186 }
 187
 188 static const struct i2c_device_id bd6107_ids[] = {
 189         { "bd6107", 0 },
 190         { }
 191 };
 192 MODULE_DEVICE_TABLE(i2c, bd6107_ids);
 193
 194 static struct i2c_driver bd6107_driver = {
 195         .driver = {
 196                 .name = "bd6107",
 197         },
 198         .probe = bd6107_probe,
 199         .remove = bd6107_remove,
 200         .id_table = bd6107_ids,
 201 };
 202
 203 module_i2c_driver(bd6107_driver);
 204
 205 MODULE_DESCRIPTION("Rohm BD6107 Backlight Driver");
 206 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
 207 MODULE_LICENSE("GPL");