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/i2c.h> 13 #include <linux/module.h> 14 #include <linux/platform_data/lv5207lp.h> 15 #include <linux/slab.h> 16 17 #define LV5207LP_CTRL1 0x00 18 #define LV5207LP_CPSW (1 << 7) 19 #define LV5207LP_SCTEN (1 << 6) 20 #define LV5207LP_C10 (1 << 5) 21 #define LV5207LP_CKSW (1 << 4) 22 #define LV5207LP_RSW (1 << 3) 23 #define LV5207LP_GSW (1 << 2) 24 #define LV5207LP_BSW (1 << 1) 25 #define LV5207LP_CTRL2 0x01 26 #define LV5207LP_MSW (1 << 7) 27 #define LV5207LP_MLED4 (1 << 6) 28 #define LV5207LP_RED 0x02 29 #define LV5207LP_GREEN 0x03 30 #define LV5207LP_BLUE 0x04 31 32 #define LV5207LP_MAX_BRIGHTNESS 32 33 34 struct lv5207lp { 35 struct i2c_client *client; 36 struct backlight_device *backlight; 37 struct lv5207lp_platform_data *pdata; 38 }; 39 40 static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data) 41 { 42 return i2c_smbus_write_byte_data(lv->client, reg, data); 43 } 44 45 static int lv5207lp_backlight_update_status(struct backlight_device *backlight) 46 { 47 struct lv5207lp *lv = bl_get_data(backlight); 48 int brightness = backlight_get_brightness(backlight); 49 50 if (brightness) { 51 lv5207lp_write(lv, LV5207LP_CTRL1, 52 LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW); 53 lv5207lp_write(lv, LV5207LP_CTRL2, 54 LV5207LP_MSW | LV5207LP_MLED4 | 55 (brightness - 1)); 56 } else { 57 lv5207lp_write(lv, LV5207LP_CTRL1, 0); 58 lv5207lp_write(lv, LV5207LP_CTRL2, 0); 59 } 60 61 return 0; 62 } 63 64 static bool lv5207lp_backlight_controls_device(struct backlight_device *backlight, 65 struct device *display_dev) 66 { 67 struct lv5207lp *lv = bl_get_data(backlight); 68 69 return !lv->pdata->dev || lv->pdata->dev == display_dev; 70 } 71 72 static const struct backlight_ops lv5207lp_backlight_ops = { 73 .options = BL_CORE_SUSPENDRESUME, 74 .update_status = lv5207lp_backlight_update_status, 75 .controls_device = lv5207lp_backlight_controls_device, 76 }; 77 78 static int lv5207lp_probe(struct i2c_client *client) 79 { 80 struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev); 81 struct backlight_device *backlight; 82 struct backlight_properties props; 83 struct lv5207lp *lv; 84 85 if (pdata == NULL) { 86 dev_err(&client->dev, "No platform data supplied\n"); 87 return -EINVAL; 88 } 89 90 if (!i2c_check_functionality(client->adapter, 91 I2C_FUNC_SMBUS_BYTE_DATA)) { 92 dev_warn(&client->dev, 93 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n"); 94 return -EIO; 95 } 96 97 lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL); 98 if (!lv) 99 return -ENOMEM; 100 101 lv->client = client; 102 lv->pdata = pdata; 103 104 memset(&props, 0, sizeof(props)); 105 props.type = BACKLIGHT_RAW; 106 props.max_brightness = min_t(unsigned int, pdata->max_value, 107 LV5207LP_MAX_BRIGHTNESS); 108 props.brightness = clamp_t(unsigned int, pdata->def_value, 0, 109 props.max_brightness); 110 111 backlight = devm_backlight_device_register(&client->dev, 112 dev_name(&client->dev), &lv->client->dev, 113 lv, &lv5207lp_backlight_ops, &props); 114 if (IS_ERR(backlight)) { 115 dev_err(&client->dev, "failed to register backlight\n"); 116 return PTR_ERR(backlight); 117 } 118 119 backlight_update_status(backlight); 120 i2c_set_clientdata(client, backlight); 121 122 return 0; 123 } 124 125 static void lv5207lp_remove(struct i2c_client *client) 126 { 127 struct backlight_device *backlight = i2c_get_clientdata(client); 128 129 backlight->props.brightness = 0; 130 backlight_update_status(backlight); 131 } 132 133 static const struct i2c_device_id lv5207lp_ids[] = { 134 { "lv5207lp" }, 135 { } 136 }; 137 MODULE_DEVICE_TABLE(i2c, lv5207lp_ids); 138 139 static struct i2c_driver lv5207lp_driver = { 140 .driver = { 141 .name = "lv5207lp", 142 }, 143 .probe = lv5207lp_probe, 144 .remove = lv5207lp_remove, 145 .id_table = lv5207lp_ids, 146 }; 147 148 module_i2c_driver(lv5207lp_driver); 149 150 MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver"); 151 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 152 MODULE_LICENSE("GPL"); 153