diff options
author | Donghwa Lee <dh09.lee@samsung.com> | 2012-07-02 01:16:13 (GMT) |
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committer | Albert ARIBAUD <albert.u.boot@aribaud.net> | 2012-09-01 12:58:24 (GMT) |
commit | 6fff52b93a1abf3f3fdefd8ccc7dabf6eb4f2ca3 (patch) | |
tree | ff76c998f215c0d042d349b9a813b19fe75a7c15 /drivers/video/exynos_pwm_bl.c | |
parent | a29c832263be57d218581ba4b1cb5e2820338383 (diff) | |
download | u-boot-6fff52b93a1abf3f3fdefd8ccc7dabf6eb4f2ca3.tar.xz |
video: support exynos pwm backlight driver
This patch support exynos pwm backlight driver. It can control backlight
power and brightness by using pwm.
Signed-off-by: Donghwa Lee <dh09.lee@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
Diffstat (limited to 'drivers/video/exynos_pwm_bl.c')
-rw-r--r-- | drivers/video/exynos_pwm_bl.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/drivers/video/exynos_pwm_bl.c b/drivers/video/exynos_pwm_bl.c new file mode 100644 index 0000000..27fb0b5 --- /dev/null +++ b/drivers/video/exynos_pwm_bl.c @@ -0,0 +1,57 @@ +/* + * PWM BACKLIGHT driver for Board based on EXYNOS. + * + * Author: Donghwa Lee <dh09.lee@samsung.com> + * + * Derived from linux/drivers/video/backlight/pwm_backlight.c + * + * 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; either version 2 of the License, or (at your + * option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#include <common.h> +#include <pwm.h> +#include <linux/types.h> +#include <asm/io.h> +#include <asm/arch/cpu.h> +#include <asm/arch/gpio.h> +#include <asm/arch/pwm.h> +#include <asm/arch/pwm_backlight.h> + +static struct pwm_backlight_data *pwm; + +static int exynos_pwm_backlight_update_status(void) +{ + int brightness = pwm->brightness; + int max = pwm->max_brightness; + + if (brightness == 0) { + pwm_config(pwm->pwm_id, 0, pwm->period); + pwm_disable(pwm->pwm_id); + } else { + pwm_config(pwm->pwm_id, + brightness * pwm->period / max, pwm->period); + pwm_enable(pwm->pwm_id); + } + return 0; +} + +int exynos_pwm_backlight_init(struct pwm_backlight_data *pd) +{ + pwm = pd; + + exynos_pwm_backlight_update_status(); + + return 0; +} |