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 { 118 struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev); 119 struct backlight_device *backlight; 120 struct backlight_properties props; 121 struct bd6107 *bd; 122 int ret; 123 124 if (pdata == NULL) { 125 dev_err(&client->dev, "No platform data\n"); 126 return -EINVAL; 127 } 128 129 if (!i2c_check_functionality(client->adapter, 130 I2C_FUNC_SMBUS_BYTE_DATA)) { 131 dev_warn(&client->dev, 132 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n"); 133 return -EIO; 134 } 135 136 bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL); 137 if (!bd) 138 return -ENOMEM; 139 140 bd->client = client; 141 bd->pdata = pdata; 142 143 /* 144 * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted, 145 * so in the machine descriptor table (or other hardware description), 146 * the line should be flagged as active low so this will assert 147 * the reset. 148 */ 149 bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH); 150 if (IS_ERR(bd->reset)) { 151 dev_err(&client->dev, "unable to request reset GPIO\n"); 152 ret = PTR_ERR(bd->reset); 153 return ret; 154 } 155 156 memset(&props, 0, sizeof(props)); 157 props.type = BACKLIGHT_RAW; 158 props.max_brightness = 128; 159 props.brightness = clamp_t(unsigned int, pdata->def_value, 0, 160 props.max_brightness); 161 162 backlight = devm_backlight_device_register(&client->dev, 163 dev_name(&client->dev), 164 &bd->client->dev, bd, 165 &bd6107_backlight_ops, &props); 166 if (IS_ERR(backlight)) { 167 dev_err(&client->dev, "failed to register backlight\n"); 168 return PTR_ERR(backlight); 169 } 170 171 backlight_update_status(backlight); 172 i2c_set_clientdata(client, backlight); 173 174 return 0; 175 } 176 177 static void bd6107_remove(struct i2c_client *client) 178 { 179 struct backlight_device *backlight = i2c_get_clientdata(client); 180 181 backlight->props.brightness = 0; 182 backlight_update_status(backlight); 183 } 184 185 static const struct i2c_device_id bd6107_ids[] = { 186 { "bd6107", 0 }, 187 { } 188 }; 189 MODULE_DEVICE_TABLE(i2c, bd6107_ids); 190 191 static struct i2c_driver bd6107_driver = { 192 .driver = { 193 .name = "bd6107", 194 }, 195 .probe_new = bd6107_probe, 196 .remove = bd6107_remove, 197 .id_table = bd6107_ids, 198 }; 199 200 module_i2c_driver(bd6107_driver); 201 202 MODULE_DESCRIPTION("Rohm BD6107 Backlight Driver"); 203 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 204 MODULE_LICENSE("GPL"); 205