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/gpio/consumer.h> 14 #include <linux/i2c.h> 15 #include <linux/module.h> 16 #include <linux/platform_data/bd6107.h> 17 #include <linux/slab.h> 18 19 #define BD6107_PSCNT1 0x00 20 #define BD6107_PSCNT1_PSCNTREG2 (1 << 2) 21 #define BD6107_PSCNT1_PSCNTREG1 (1 << 0) 22 #define BD6107_REGVSET 0x02 23 #define BD6107_REGVSET_REG1VSET_2_85V (1 << 2) 24 #define BD6107_REGVSET_REG1VSET_2_80V (0 << 2) 25 #define BD6107_LEDCNT1 0x03 26 #define BD6107_LEDCNT1_LEDONOFF2 (1 << 1) 27 #define BD6107_LEDCNT1_LEDONOFF1 (1 << 0) 28 #define BD6107_PORTSEL 0x04 29 #define BD6107_PORTSEL_LEDM(n) (1 << (n)) 30 #define BD6107_RGB1CNT1 0x05 31 #define BD6107_RGB1CNT2 0x06 32 #define BD6107_RGB1CNT3 0x07 33 #define BD6107_RGB1CNT4 0x08 34 #define BD6107_RGB1CNT5 0x09 35 #define BD6107_RGB1FLM 0x0a 36 #define BD6107_RGB2CNT1 0x0b 37 #define BD6107_RGB2CNT2 0x0c 38 #define BD6107_RGB2CNT3 0x0d 39 #define BD6107_RGB2CNT4 0x0e 40 #define BD6107_RGB2CNT5 0x0f 41 #define BD6107_RGB2FLM 0x10 42 #define BD6107_PSCONT3 0x11 43 #define BD6107_SMMONCNT 0x12 44 #define BD6107_DCDCCNT 0x13 45 #define BD6107_IOSEL 0x14 46 #define BD6107_OUT1 0x15 47 #define BD6107_OUT2 0x16 48 #define BD6107_MASK1 0x17 49 #define BD6107_MASK2 0x18 50 #define BD6107_FACTOR1 0x19 51 #define BD6107_FACTOR2 0x1a 52 #define BD6107_CLRFACT1 0x1b 53 #define BD6107_CLRFACT2 0x1c 54 #define BD6107_STATE1 0x1d 55 #define BD6107_LSIVER 0x1e 56 #define BD6107_GRPSEL 0x1f 57 #define BD6107_LEDCNT2 0x20 58 #define BD6107_LEDCNT3 0x21 59 #define BD6107_MCURRENT 0x22 60 #define BD6107_MAINCNT1 0x23 61 #define BD6107_MAINCNT2 0x24 62 #define BD6107_SLOPECNT 0x25 63 #define BD6107_MSLOPE 0x26 64 #define BD6107_RGBSLOPE 0x27 65 #define BD6107_TEST 0x29 66 #define BD6107_SFTRST 0x2a 67 #define BD6107_SFTRSTGD 0x2b 68 69 struct bd6107 { 70 struct i2c_client *client; 71 struct backlight_device *backlight; 72 struct bd6107_platform_data *pdata; 73 struct gpio_desc *reset; 74 }; 75 76 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data) 77 { 78 return i2c_smbus_write_byte_data(bd->client, reg, data); 79 } 80 81 static int bd6107_backlight_update_status(struct backlight_device *backlight) 82 { 83 struct bd6107 *bd = bl_get_data(backlight); 84 int brightness = backlight_get_brightness(backlight); 85 86 if (brightness) { 87 bd6107_write(bd, BD6107_PORTSEL, BD6107_PORTSEL_LEDM(2) | 88 BD6107_PORTSEL_LEDM(1) | BD6107_PORTSEL_LEDM(0)); 89 bd6107_write(bd, BD6107_MAINCNT1, brightness); 90 bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1); 91 } else { 92 /* Assert the reset line (gpiolib will handle active low) */ 93 gpiod_set_value(bd->reset, 1); 94 msleep(24); 95 gpiod_set_value(bd->reset, 0); 96 } 97 98 return 0; 99 } 100 101 static bool bd6107_backlight_controls_device(struct backlight_device *backlight, 102 struct device *display_dev) 103 { 104 struct bd6107 *bd = bl_get_data(backlight); 105 106 return !bd->pdata->dev || bd->pdata->dev == display_dev; 107 } 108 109 static const struct backlight_ops bd6107_backlight_ops = { 110 .options = BL_CORE_SUSPENDRESUME, 111 .update_status = bd6107_backlight_update_status, 112 .controls_device = bd6107_backlight_controls_device, 113 }; 114 115 static int bd6107_probe(struct i2c_client *client) 116 { 117 struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev); 118 struct backlight_device *backlight; 119 struct backlight_properties props; 120 struct bd6107 *bd; 121 122 if (pdata == NULL) { 123 dev_err(&client->dev, "No platform data\n"); 124 return -EINVAL; 125 } 126 127 if (!i2c_check_functionality(client->adapter, 128 I2C_FUNC_SMBUS_BYTE_DATA)) { 129 dev_warn(&client->dev, 130 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n"); 131 return -EIO; 132 } 133 134 bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL); 135 if (!bd) 136 return -ENOMEM; 137 138 bd->client = client; 139 bd->pdata = pdata; 140 141 /* 142 * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted, 143 * so in the machine descriptor table (or other hardware description), 144 * the line should be flagged as active low so this will assert 145 * the reset. 146 */ 147 bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH); 148 if (IS_ERR(bd->reset)) 149 return dev_err_probe(&client->dev, PTR_ERR(bd->reset), 150 "unable to request reset GPIO\n"); 151 152 memset(&props, 0, sizeof(props)); 153 props.type = BACKLIGHT_RAW; 154 props.max_brightness = 128; 155 props.brightness = clamp_t(unsigned int, pdata->def_value, 0, 156 props.max_brightness); 157 158 backlight = devm_backlight_device_register(&client->dev, 159 dev_name(&client->dev), 160 &bd->client->dev, bd, 161 &bd6107_backlight_ops, &props); 162 if (IS_ERR(backlight)) { 163 dev_err(&client->dev, "failed to register backlight\n"); 164 return PTR_ERR(backlight); 165 } 166 167 backlight_update_status(backlight); 168 i2c_set_clientdata(client, backlight); 169 170 return 0; 171 } 172 173 static void bd6107_remove(struct i2c_client *client) 174 { 175 struct backlight_device *backlight = i2c_get_clientdata(client); 176 177 backlight->props.brightness = 0; 178 backlight_update_status(backlight); 179 } 180 181 static const struct i2c_device_id bd6107_ids[] = { 182 { "bd6107" }, 183 { } 184 }; 185 MODULE_DEVICE_TABLE(i2c, bd6107_ids); 186 187 static struct i2c_driver bd6107_driver = { 188 .driver = { 189 .name = "bd6107", 190 }, 191 .probe = bd6107_probe, 192 .remove = bd6107_remove, 193 .id_table = bd6107_ids, 194 }; 195 196 module_i2c_driver(bd6107_driver); 197 198 MODULE_DESCRIPTION("Rohm BD6107 Backlight Driver"); 199 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 200 MODULE_LICENSE("GPL"); 201