1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Sanyo LV5207LP 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/err.h> 12 #include <linux/fb.h> 13 #include <linux/i2c.h> 14 #include <linux/module.h> 15 #include <linux/platform_data/lv5207lp.h> 16 #include <linux/slab.h> 17 18 #define LV5207LP_CTRL1 0x00 19 #define LV5207LP_CPSW (1 << 7) 20 #define LV5207LP_SCTEN (1 << 6) 21 #define LV5207LP_C10 (1 << 5) 22 #define LV5207LP_CKSW (1 << 4) 23 #define LV5207LP_RSW (1 << 3) 24 #define LV5207LP_GSW (1 << 2) 25 #define LV5207LP_BSW (1 << 1) 26 #define LV5207LP_CTRL2 0x01 27 #define LV5207LP_MSW (1 << 7) 28 #define LV5207LP_MLED4 (1 << 6) 29 #define LV5207LP_RED 0x02 30 #define LV5207LP_GREEN 0x03 31 #define LV5207LP_BLUE 0x04 32 33 #define LV5207LP_MAX_BRIGHTNESS 32 34 35 struct lv5207lp { 36 struct i2c_client *client; 37 struct backlight_device *backlight; 38 struct lv5207lp_platform_data *pdata; 39 }; 40 41 static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data) 42 { 43 return i2c_smbus_write_byte_data(lv->client, reg, data); 44 } 45 46 static int lv5207lp_backlight_update_status(struct backlight_device *backlight) 47 { 48 struct lv5207lp *lv = bl_get_data(backlight); 49 int brightness = backlight_get_brightness(backlight); 50 51 if (brightness) { 52 lv5207lp_write(lv, LV5207LP_CTRL1, 53 LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW); 54 lv5207lp_write(lv, LV5207LP_CTRL2, 55 LV5207LP_MSW | LV5207LP_MLED4 | 56 (brightness - 1)); 57 } else { 58 lv5207lp_write(lv, LV5207LP_CTRL1, 0); 59 lv5207lp_write(lv, LV5207LP_CTRL2, 0); 60 } 61 62 return 0; 63 } 64 65 static int lv5207lp_backlight_check_fb(struct backlight_device *backlight, 66 struct fb_info *info) 67 { 68 struct lv5207lp *lv = bl_get_data(backlight); 69 70 return lv->pdata->fbdev == NULL || lv->pdata->fbdev == info->dev; 71 } 72 73 static const struct backlight_ops lv5207lp_backlight_ops = { 74 .options = BL_CORE_SUSPENDRESUME, 75 .update_status = lv5207lp_backlight_update_status, 76 .check_fb = lv5207lp_backlight_check_fb, 77 }; 78 79 static int lv5207lp_probe(struct i2c_client *client, 80 const struct i2c_device_id *id) 81 { 82 struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev); 83 struct backlight_device *backlight; 84 struct backlight_properties props; 85 struct lv5207lp *lv; 86 87 if (pdata == NULL) { 88 dev_err(&client->dev, "No platform data supplied\n"); 89 return -EINVAL; 90 } 91 92 if (!i2c_check_functionality(client->adapter, 93 I2C_FUNC_SMBUS_BYTE_DATA)) { 94 dev_warn(&client->dev, 95 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n"); 96 return -EIO; 97 } 98 99 lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL); 100 if (!lv) 101 return -ENOMEM; 102 103 lv->client = client; 104 lv->pdata = pdata; 105 106 memset(&props, 0, sizeof(props)); 107 props.type = BACKLIGHT_RAW; 108 props.max_brightness = min_t(unsigned int, pdata->max_value, 109 LV5207LP_MAX_BRIGHTNESS); 110 props.brightness = clamp_t(unsigned int, pdata->def_value, 0, 111 props.max_brightness); 112 113 backlight = devm_backlight_device_register(&client->dev, 114 dev_name(&client->dev), &lv->client->dev, 115 lv, &lv5207lp_backlight_ops, &props); 116 if (IS_ERR(backlight)) { 117 dev_err(&client->dev, "failed to register backlight\n"); 118 return PTR_ERR(backlight); 119 } 120 121 backlight_update_status(backlight); 122 i2c_set_clientdata(client, backlight); 123 124 return 0; 125 } 126 127 static void lv5207lp_remove(struct i2c_client *client) 128 { 129 struct backlight_device *backlight = i2c_get_clientdata(client); 130 131 backlight->props.brightness = 0; 132 backlight_update_status(backlight); 133 } 134 135 static const struct i2c_device_id lv5207lp_ids[] = { 136 { "lv5207lp", 0 }, 137 { } 138 }; 139 MODULE_DEVICE_TABLE(i2c, lv5207lp_ids); 140 141 static struct i2c_driver lv5207lp_driver = { 142 .driver = { 143 .name = "lv5207lp", 144 }, 145 .probe = lv5207lp_probe, 146 .remove = lv5207lp_remove, 147 .id_table = lv5207lp_ids, 148 }; 149 150 module_i2c_driver(lv5207lp_driver); 151 152 MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver"); 153 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 154 MODULE_LICENSE("GPL"); 155