summaryrefslogtreecommitdiff
path: root/drivers/video/backlight/lv5207lp.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/video/backlight/lv5207lp.c')
-rw-r--r--drivers/video/backlight/lv5207lp.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/video/backlight/lv5207lp.c b/drivers/video/backlight/lv5207lp.c
new file mode 100644
index 000000000000..498fd73d59b9
--- /dev/null
+++ b/drivers/video/backlight/lv5207lp.c
@@ -0,0 +1,171 @@
+/*
+ * Sanyo LV5207LP LED Driver
+ *
+ * Copyright (C) 2013 Ideas on board SPRL
+ *
+ * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/backlight.h>
+#include <linux/err.h>
+#include <linux/fb.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/platform_data/lv5207lp.h>
+#include <linux/slab.h>
+
+#define LV5207LP_CTRL1 0x00
+#define LV5207LP_CPSW (1 << 7)
+#define LV5207LP_SCTEN (1 << 6)
+#define LV5207LP_C10 (1 << 5)
+#define LV5207LP_CKSW (1 << 4)
+#define LV5207LP_RSW (1 << 3)
+#define LV5207LP_GSW (1 << 2)
+#define LV5207LP_BSW (1 << 1)
+#define LV5207LP_CTRL2 0x01
+#define LV5207LP_MSW (1 << 7)
+#define LV5207LP_MLED4 (1 << 6)
+#define LV5207LP_RED 0x02
+#define LV5207LP_GREEN 0x03
+#define LV5207LP_BLUE 0x04
+
+#define LV5207LP_MAX_BRIGHTNESS 32
+
+struct lv5207lp {
+ struct i2c_client *client;
+ struct backlight_device *backlight;
+ struct lv5207lp_platform_data *pdata;
+};
+
+static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
+{
+ return i2c_smbus_write_byte_data(lv->client, reg, data);
+}
+
+static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
+{
+ struct lv5207lp *lv = bl_get_data(backlight);
+ int brightness = backlight->props.brightness;
+
+ if (backlight->props.power != FB_BLANK_UNBLANK ||
+ backlight->props.fb_blank != FB_BLANK_UNBLANK ||
+ backlight->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
+ brightness = 0;
+
+ if (brightness) {
+ lv5207lp_write(lv, LV5207LP_CTRL1,
+ LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
+ lv5207lp_write(lv, LV5207LP_CTRL2,
+ LV5207LP_MSW | LV5207LP_MLED4 |
+ (brightness - 1));
+ } else {
+ lv5207lp_write(lv, LV5207LP_CTRL1, 0);
+ lv5207lp_write(lv, LV5207LP_CTRL2, 0);
+ }
+
+ return 0;
+}
+
+static int lv5207lp_backlight_get_brightness(struct backlight_device *backlight)
+{
+ return backlight->props.brightness;
+}
+
+static int lv5207lp_backlight_check_fb(struct backlight_device *backlight,
+ struct fb_info *info)
+{
+ struct lv5207lp *lv = bl_get_data(backlight);
+
+ return lv->pdata->fbdev == NULL || lv->pdata->fbdev == info->dev;
+}
+
+static const struct backlight_ops lv5207lp_backlight_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .update_status = lv5207lp_backlight_update_status,
+ .get_brightness = lv5207lp_backlight_get_brightness,
+ .check_fb = lv5207lp_backlight_check_fb,
+};
+
+static int lv5207lp_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct lv5207lp_platform_data *pdata = client->dev.platform_data;
+ struct backlight_device *backlight;
+ struct backlight_properties props;
+ struct lv5207lp *lv;
+
+ if (pdata == NULL) {
+ dev_err(&client->dev, "No platform data supplied\n");
+ return -EINVAL;
+ }
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA)) {
+ dev_warn(&client->dev,
+ "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
+ return -EIO;
+ }
+
+ lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
+ if (!lv)
+ return -ENOMEM;
+
+ lv->client = client;
+ lv->pdata = pdata;
+
+ memset(&props, 0, sizeof(props));
+ props.type = BACKLIGHT_RAW;
+ props.max_brightness = min_t(unsigned int, pdata->max_value,
+ LV5207LP_MAX_BRIGHTNESS);
+ props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
+ props.max_brightness);
+
+ backlight = backlight_device_register(dev_name(&client->dev),
+ &lv->client->dev, lv,
+ &lv5207lp_backlight_ops, &props);
+ if (IS_ERR(backlight)) {
+ dev_err(&client->dev, "failed to register backlight\n");
+ return PTR_ERR(backlight);
+ }
+
+ backlight_update_status(backlight);
+ i2c_set_clientdata(client, backlight);
+
+ return 0;
+}
+
+static int lv5207lp_remove(struct i2c_client *client)
+{
+ struct backlight_device *backlight = i2c_get_clientdata(client);
+
+ backlight->props.brightness = 0;
+ backlight_update_status(backlight);
+ backlight_device_unregister(backlight);
+
+ return 0;
+}
+
+static const struct i2c_device_id lv5207lp_ids[] = {
+ { "lv5207lp", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
+
+static struct i2c_driver lv5207lp_driver = {
+ .driver = {
+ .name = "lv5207lp",
+ },
+ .probe = lv5207lp_probe,
+ .remove = lv5207lp_remove,
+ .id_table = lv5207lp_ids,
+};
+
+module_i2c_driver(lv5207lp_driver);
+
+MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
+MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
+MODULE_LICENSE("GPL");