video/backlight/bd6107.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * ROHM Semiconductor BD6107 LED Driver
0004  *
0005  * Copyright (C) 2013 Ideas on board SPRL
0006  *
0007  * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
0008  */
0009
0010 #include <linux/backlight.h>
0011 #include <linux/delay.h>
0012 #include <linux/err.h>
0013 #include <linux/fb.h>
0014 #include <linux/gpio/consumer.h>
0015 #include <linux/i2c.h>
0016 #include <linux/module.h>
0017 #include <linux/platform_data/bd6107.h>
0018 #include <linux/slab.h>
0019
0020 #define BD6107_PSCNT1               0x00
0021 #define BD6107_PSCNT1_PSCNTREG2         (1 << 2)
0022 #define BD6107_PSCNT1_PSCNTREG1         (1 << 0)
0023 #define BD6107_REGVSET              0x02
0024 #define BD6107_REGVSET_REG1VSET_2_85V       (1 << 2)
0025 #define BD6107_REGVSET_REG1VSET_2_80V       (0 << 2)
0026 #define BD6107_LEDCNT1              0x03
0027 #define BD6107_LEDCNT1_LEDONOFF2        (1 << 1)
0028 #define BD6107_LEDCNT1_LEDONOFF1        (1 << 0)
0029 #define BD6107_PORTSEL              0x04
0030 #define BD6107_PORTSEL_LEDM(n)          (1 << (n))
0031 #define BD6107_RGB1CNT1             0x05
0032 #define BD6107_RGB1CNT2             0x06
0033 #define BD6107_RGB1CNT3             0x07
0034 #define BD6107_RGB1CNT4             0x08
0035 #define BD6107_RGB1CNT5             0x09
0036 #define BD6107_RGB1FLM              0x0a
0037 #define BD6107_RGB2CNT1             0x0b
0038 #define BD6107_RGB2CNT2             0x0c
0039 #define BD6107_RGB2CNT3             0x0d
0040 #define BD6107_RGB2CNT4             0x0e
0041 #define BD6107_RGB2CNT5             0x0f
0042 #define BD6107_RGB2FLM              0x10
0043 #define BD6107_PSCONT3              0x11
0044 #define BD6107_SMMONCNT             0x12
0045 #define BD6107_DCDCCNT              0x13
0046 #define BD6107_IOSEL                0x14
0047 #define BD6107_OUT1             0x15
0048 #define BD6107_OUT2             0x16
0049 #define BD6107_MASK1                0x17
0050 #define BD6107_MASK2                0x18
0051 #define BD6107_FACTOR1              0x19
0052 #define BD6107_FACTOR2              0x1a
0053 #define BD6107_CLRFACT1             0x1b
0054 #define BD6107_CLRFACT2             0x1c
0055 #define BD6107_STATE1               0x1d
0056 #define BD6107_LSIVER               0x1e
0057 #define BD6107_GRPSEL               0x1f
0058 #define BD6107_LEDCNT2              0x20
0059 #define BD6107_LEDCNT3              0x21
0060 #define BD6107_MCURRENT             0x22
0061 #define BD6107_MAINCNT1             0x23
0062 #define BD6107_MAINCNT2             0x24
0063 #define BD6107_SLOPECNT             0x25
0064 #define BD6107_MSLOPE               0x26
0065 #define BD6107_RGBSLOPE             0x27
0066 #define BD6107_TEST             0x29
0067 #define BD6107_SFTRST               0x2a
0068 #define BD6107_SFTRSTGD             0x2b
0069
0070 struct bd6107 {
0071     struct i2c_client *client;
0072     struct backlight_device *backlight;
0073     struct bd6107_platform_data *pdata;
0074     struct gpio_desc *reset;
0075 };
0076
0077 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data)
0078 {
0079     return i2c_smbus_write_byte_data(bd->client, reg, data);
0080 }
0081
0082 static int bd6107_backlight_update_status(struct backlight_device *backlight)
0083 {
0084     struct bd6107 *bd = bl_get_data(backlight);
0085     int brightness = backlight_get_brightness(backlight);
0086
0087     if (brightness) {
0088         bd6107_write(bd, BD6107_PORTSEL, BD6107_PORTSEL_LEDM(2) |
0089                  BD6107_PORTSEL_LEDM(1) | BD6107_PORTSEL_LEDM(0));
0090         bd6107_write(bd, BD6107_MAINCNT1, brightness);
0091         bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1);
0092     } else {
0093         /* Assert the reset line (gpiolib will handle active low) */
0094         gpiod_set_value(bd->reset, 1);
0095         msleep(24);
0096         gpiod_set_value(bd->reset, 0);
0097     }
0098
0099     return 0;
0100 }
0101
0102 static int bd6107_backlight_check_fb(struct backlight_device *backlight,
0103                        struct fb_info *info)
0104 {
0105     struct bd6107 *bd = bl_get_data(backlight);
0106
0107     return bd->pdata->fbdev == NULL || bd->pdata->fbdev == info->dev;
0108 }
0109
0110 static const struct backlight_ops bd6107_backlight_ops = {
0111     .options    = BL_CORE_SUSPENDRESUME,
0112     .update_status  = bd6107_backlight_update_status,
0113     .check_fb   = bd6107_backlight_check_fb,
0114 };
0115
0116 static int bd6107_probe(struct i2c_client *client,
0117               const struct i2c_device_id *id)
0118 {
0119     struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev);
0120     struct backlight_device *backlight;
0121     struct backlight_properties props;
0122     struct bd6107 *bd;
0123     int ret;
0124
0125     if (pdata == NULL) {
0126         dev_err(&client->dev, "No platform data\n");
0127         return -EINVAL;
0128     }
0129
0130     if (!i2c_check_functionality(client->adapter,
0131                      I2C_FUNC_SMBUS_BYTE_DATA)) {
0132         dev_warn(&client->dev,
0133              "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
0134         return -EIO;
0135     }
0136
0137     bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL);
0138     if (!bd)
0139         return -ENOMEM;
0140
0141     bd->client = client;
0142     bd->pdata = pdata;
0143
0144     /*
0145      * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted,
0146      * so in the machine descriptor table (or other hardware description),
0147      * the line should be flagged as active low so this will assert
0148      * the reset.
0149      */
0150     bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
0151     if (IS_ERR(bd->reset)) {
0152         dev_err(&client->dev, "unable to request reset GPIO\n");
0153         ret = PTR_ERR(bd->reset);
0154         return ret;
0155     }
0156
0157     memset(&props, 0, sizeof(props));
0158     props.type = BACKLIGHT_RAW;
0159     props.max_brightness = 128;
0160     props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
0161                    props.max_brightness);
0162
0163     backlight = devm_backlight_device_register(&client->dev,
0164                           dev_name(&client->dev),
0165                           &bd->client->dev, bd,
0166                           &bd6107_backlight_ops, &props);
0167     if (IS_ERR(backlight)) {
0168         dev_err(&client->dev, "failed to register backlight\n");
0169         return PTR_ERR(backlight);
0170     }
0171
0172     backlight_update_status(backlight);
0173     i2c_set_clientdata(client, backlight);
0174
0175     return 0;
0176 }
0177
0178 static int bd6107_remove(struct i2c_client *client)
0179 {
0180     struct backlight_device *backlight = i2c_get_clientdata(client);
0181
0182     backlight->props.brightness = 0;
0183     backlight_update_status(backlight);
0184
0185     return 0;
0186 }
0187
0188 static const struct i2c_device_id bd6107_ids[] = {
0189     { "bd6107", 0 },
0190     { }
0191 };
0192 MODULE_DEVICE_TABLE(i2c, bd6107_ids);
0193
0194 static struct i2c_driver bd6107_driver = {
0195     .driver = {
0196         .name = "bd6107",
0197     },
0198     .probe = bd6107_probe,
0199     .remove = bd6107_remove,
0200     .id_table = bd6107_ids,
0201 };
0202
0203 module_i2c_driver(bd6107_driver);
0204
0205 MODULE_DESCRIPTION("Rohm BD6107 Backlight Driver");
0206 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
0207 MODULE_LICENSE("GPL");