1 /* 2 * ROHM Semiconductor BD6107 LED Driver 3 * 4 * Copyright (C) 2013 Ideas on board SPRL 5 * 6 * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com> 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 */ 12 13 #include <linux/backlight.h> 14 #include <linux/delay.h> 15 #include <linux/err.h> 16 #include <linux/fb.h> 17 #include <linux/gpio.h> 18 #include <linux/i2c.h> 19 #include <linux/module.h> 20 #include <linux/platform_data/bd6107.h> 21 #include <linux/slab.h> 22 23 #define BD6107_PSCNT1 0x00 24 #define BD6107_PSCNT1_PSCNTREG2 (1 << 2) 25 #define BD6107_PSCNT1_PSCNTREG1 (1 << 0) 26 #define BD6107_REGVSET 0x02 27 #define BD6107_REGVSET_REG1VSET_2_85V (1 << 2) 28 #define BD6107_REGVSET_REG1VSET_2_80V (0 << 2) 29 #define BD6107_LEDCNT1 0x03 30 #define BD6107_LEDCNT1_LEDONOFF2 (1 << 1) 31 #define BD6107_LEDCNT1_LEDONOFF1 (1 << 0) 32 #define BD6107_PORTSEL 0x04 33 #define BD6107_PORTSEL_LEDM(n) (1 << (n)) 34 #define BD6107_RGB1CNT1 0x05 35 #define BD6107_RGB1CNT2 0x06 36 #define BD6107_RGB1CNT3 0x07 37 #define BD6107_RGB1CNT4 0x08 38 #define BD6107_RGB1CNT5 0x09 39 #define BD6107_RGB1FLM 0x0a 40 #define BD6107_RGB2CNT1 0x0b 41 #define BD6107_RGB2CNT2 0x0c 42 #define BD6107_RGB2CNT3 0x0d 43 #define BD6107_RGB2CNT4 0x0e 44 #define BD6107_RGB2CNT5 0x0f 45 #define BD6107_RGB2FLM 0x10 46 #define BD6107_PSCONT3 0x11 47 #define BD6107_SMMONCNT 0x12 48 #define BD6107_DCDCCNT 0x13 49 #define BD6107_IOSEL 0x14 50 #define BD6107_OUT1 0x15 51 #define BD6107_OUT2 0x16 52 #define BD6107_MASK1 0x17 53 #define BD6107_MASK2 0x18 54 #define BD6107_FACTOR1 0x19 55 #define BD6107_FACTOR2 0x1a 56 #define BD6107_CLRFACT1 0x1b 57 #define BD6107_CLRFACT2 0x1c 58 #define BD6107_STATE1 0x1d 59 #define BD6107_LSIVER 0x1e 60 #define BD6107_GRPSEL 0x1f 61 #define BD6107_LEDCNT2 0x20 62 #define BD6107_LEDCNT3 0x21 63 #define BD6107_MCURRENT 0x22 64 #define BD6107_MAINCNT1 0x23 65 #define BD6107_MAINCNT2 0x24 66 #define BD6107_SLOPECNT 0x25 67 #define BD6107_MSLOPE 0x26 68 #define BD6107_RGBSLOPE 0x27 69 #define BD6107_TEST 0x29 70 #define BD6107_SFTRST 0x2a 71 #define BD6107_SFTRSTGD 0x2b 72 73 struct bd6107 { 74 struct i2c_client *client; 75 struct backlight_device *backlight; 76 struct bd6107_platform_data *pdata; 77 }; 78 79 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data) 80 { 81 return i2c_smbus_write_byte_data(bd->client, reg, data); 82 } 83 84 static int bd6107_backlight_update_status(struct backlight_device *backlight) 85 { 86 struct bd6107 *bd = bl_get_data(backlight); 87 int brightness = backlight->props.brightness; 88 89 if (backlight->props.power != FB_BLANK_UNBLANK || 90 backlight->props.fb_blank != FB_BLANK_UNBLANK || 91 backlight->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK)) 92 brightness = 0; 93 94 if (brightness) { 95 bd6107_write(bd, BD6107_PORTSEL, BD6107_PORTSEL_LEDM(2) | 96 BD6107_PORTSEL_LEDM(1) | BD6107_PORTSEL_LEDM(0)); 97 bd6107_write(bd, BD6107_MAINCNT1, brightness); 98 bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1); 99 } else { 100 gpio_set_value(bd->pdata->reset, 0); 101 msleep(24); 102 gpio_set_value(bd->pdata->reset, 1); 103 } 104 105 return 0; 106 } 107 108 static int bd6107_backlight_check_fb(struct backlight_device *backlight, 109 struct fb_info *info) 110 { 111 struct bd6107 *bd = bl_get_data(backlight); 112 113 return bd->pdata->fbdev == NULL || bd->pdata->fbdev == info->dev; 114 } 115 116 static const struct backlight_ops bd6107_backlight_ops = { 117 .options = BL_CORE_SUSPENDRESUME, 118 .update_status = bd6107_backlight_update_status, 119 .check_fb = bd6107_backlight_check_fb, 120 }; 121 122 static int bd6107_probe(struct i2c_client *client, 123 const struct i2c_device_id *id) 124 { 125 struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev); 126 struct backlight_device *backlight; 127 struct backlight_properties props; 128 struct bd6107 *bd; 129 int ret; 130 131 if (pdata == NULL || !pdata->reset) { 132 dev_err(&client->dev, "No reset GPIO in platform data\n"); 133 return -EINVAL; 134 } 135 136 if (!i2c_check_functionality(client->adapter, 137 I2C_FUNC_SMBUS_BYTE_DATA)) { 138 dev_warn(&client->dev, 139 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n"); 140 return -EIO; 141 } 142 143 bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL); 144 if (!bd) 145 return -ENOMEM; 146 147 bd->client = client; 148 bd->pdata = pdata; 149 150 ret = devm_gpio_request_one(&client->dev, pdata->reset, 151 GPIOF_DIR_OUT | GPIOF_INIT_LOW, "reset"); 152 if (ret < 0) { 153 dev_err(&client->dev, "unable to request reset GPIO\n"); 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"); 208