linux-imx

/*

 * tps65217_bl.c

 *

 * TPS65217 backlight driver

 *

 * Copyright (C) 2012 Matthias Kaehlcke

 * Author: Matthias Kaehlcke <matthias@kaehlcke.net>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License as

 * published by the Free Software Foundation version 2.

 *

 * This program is distributed "as is" WITHOUT ANY WARRANTY of any

 * kind, whether express or implied; without even the implied warranty

 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

​

#include <linux/kernel.h>

#include <linux/backlight.h>

#include <linux/err.h>

#include <linux/fb.h>

#include <linux/mfd/tps65217.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/slab.h>

​

struct tps65217_bl {

    struct tps65217 *tps;

    struct device *dev;

    struct backlight_device *bl;

    bool is_enabled;

};

​

static int tps65217_bl_enable(struct tps65217_bl *tps65217_bl)

{

    int rc;

​

    rc = tps65217_set_bits(tps65217_bl->tps, TPS65217_REG_WLEDCTRL1,

            TPS65217_WLEDCTRL1_ISINK_ENABLE,

            TPS65217_WLEDCTRL1_ISINK_ENABLE, TPS65217_PROTECT_NONE);

    if (rc) {

        dev_err(tps65217_bl->dev,

            "failed to enable backlight: %d\n", rc);

        return rc;

    }

​

    tps65217_bl->is_enabled = true;

​

    dev_dbg(tps65217_bl->dev, "backlight enabled\n");

​

    return 0;

}

​

static int tps65217_bl_disable(struct tps65217_bl *tps65217_bl)

{

    int rc;

​

    rc = tps65217_clear_bits(tps65217_bl->tps,

                TPS65217_REG_WLEDCTRL1,

                TPS65217_WLEDCTRL1_ISINK_ENABLE,

                TPS65217_PROTECT_NONE);

    if (rc) {

        dev_err(tps65217_bl->dev,

            "failed to disable backlight: %d\n", rc);

        return rc;

    }

​

    tps65217_bl->is_enabled = false;

​

    dev_dbg(tps65217_bl->dev, "backlight disabled\n");

​

    return 0;

}

​

static int tps65217_bl_update_status(struct backlight_device *bl)

{

    struct tps65217_bl *tps65217_bl = bl_get_data(bl);

    int rc;

    int brightness = bl->props.brightness;

​

    if (bl->props.state & BL_CORE_SUSPENDED)

        brightness = 0;

​

    if ((bl->props.power != FB_BLANK_UNBLANK) ||

        (bl->props.fb_blank != FB_BLANK_UNBLANK))

        /* framebuffer in low power mode or blanking active */

        brightness = 0;

​

    if (brightness > 0) {

        rc = tps65217_reg_write(tps65217_bl->tps,

                    TPS65217_REG_WLEDCTRL2,