[PATCH V2 3/7] ARM: EXYNOS5: add machine specific support for LCD
Leela Krishna Amudala
l.krishna at samsung.com
Thu Jul 19 09:21:48 EDT 2012
Hello Marek,
On Wed, Jul 18, 2012 at 12:15 PM, Marek Szyprowski
<m.szyprowski at samsung.com> wrote:
> Hello,
>
> On Wednesday, July 18, 2012 7:57 AM Leela Krishna Amudala wrote:
>
>> This patch adds machine specific support for LCD controller like setting power to LCD
>> and adding LCD platform device.
>>
>> Signed-off-by: Prathyush K <prathyush.k at samsung.com>
>> Signed-off-by: Leela Krishna Amudala <l.krishna at samsung.com>
>> ---
>> arch/arm/mach-exynos/mach-exynos5-dt.c | 56 ++++++++++++++++++++++++++++++++
>> 1 files changed, 56 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arm/mach-exynos/mach-exynos5-dt.c b/arch/arm/mach-exynos/mach-exynos5-dt.c
>> index e7113cc..02a0e68 100644
>> --- a/arch/arm/mach-exynos/mach-exynos5-dt.c
>> +++ b/arch/arm/mach-exynos/mach-exynos5-dt.c
>> @@ -13,6 +13,7 @@
>> #include <linux/serial_core.h>
>> #include <linux/pwm_backlight.h>
>> #include <linux/gpio.h>
>> +#include <linux/delay.h>
>>
>> #include <asm/mach/arch.h>
>> #include <asm/hardware/gic.h>
>> @@ -24,6 +25,7 @@
>> #include <plat/gpio-cfg.h>
>>
>> #include "common.h"
>> +#include <video/platform_lcd.h>
>>
>> static int smdk5250_bl_notify(struct device *unused, int brightness)
>> {
>> @@ -47,6 +49,55 @@ static struct platform_pwm_backlight_data smdk5250_bl_data = {
>> .notify = smdk5250_bl_notify,
>> };
>>
>> +static void lcd_set_power(struct plat_lcd_data *pd,
>> + unsigned int power)
>> +{
>> +
>> + /* reset */
>> + gpio_request_one(EXYNOS5_GPX1(5), GPIOF_OUT_INIT_HIGH, "GPX1");
>> +
>> + mdelay(20);
>> + if (power) {
>> + /* fire nRESET on power up */
>> + gpio_set_value(EXYNOS5_GPX1(5), 0);
>> + mdelay(20);
>> + gpio_set_value(EXYNOS5_GPX1(5), 1);
>> + mdelay(20);
>> + gpio_free(EXYNOS5_GPX1(5));
>> + } else {
>> + /* fire nRESET on power off */
>> + gpio_set_value(EXYNOS5_GPX1(5), 0);
>> + mdelay(20);
>> + gpio_set_value(EXYNOS5_GPX1(5), 1);
>> + mdelay(20);
>> + gpio_free(EXYNOS5_GPX1(5));
>> + }
>> + mdelay(20);
>> +
>> + /*
>> + * Request lcd_bl_en GPIO for smdk5250_bl_notify().
>> + * TODO: Fix this so we are not at risk of requesting the GPIO
>> + * multiple times, this should be done with device tree, and
>> + * likely integrated into the plat-samsung/dev-backlight.c init.
>> + */
>> + gpio_request_one(EXYNOS5_GPX3(0), GPIOF_OUT_INIT_LOW, "GPX3");
>> +}
>> +
>> +static int smdk5250_match_fb(struct plat_lcd_data *pd, struct fb_info *info)
>> +{
>> + /* Don't call .set_power callback while unblanking */
>> + return 0;
>> +}
>> +
>> +static struct plat_lcd_data smdk5250_lcd_data = {
>> + .set_power = lcd_set_power,
>> + .match_fb = smdk5250_match_fb,
>> +};
>> +
>> +static struct platform_device smdk5250_lcd = {
>> + .name = "platform-lcd",
>> + .dev.platform_data = &smdk5250_lcd_data,
>> +};
>> /*
>> * The following lookup table is used to override device names when devices
>> * are registered from device tree. This is temporarily added to enable
>> @@ -85,6 +136,10 @@ static const struct of_dev_auxdata exynos5250_auxdata_lookup[] __initconst
>> = {
>> {},
>> };
>>
>> +static struct platform_device *smdk5250_devices[] __initdata = {
>> + &smdk5250_lcd, /* for platform_lcd device */
>> +};
>> +
>> static void __init exynos5250_dt_map_io(void)
>> {
>> exynos_init_io(NULL, 0);
>> @@ -96,6 +151,7 @@ static void __init exynos5250_dt_machine_init(void)
>> samsung_bl_set(&smdk5250_bl_gpio_info, &smdk5250_bl_data);
>> of_platform_populate(NULL, of_default_bus_match_table,
>> exynos5250_auxdata_lookup, NULL);
>> + platform_add_devices(smdk5250_devices, ARRAY_SIZE(smdk5250_devices));
>> }
>>
>> static char const *exynos5250_dt_compat[] __initdata = {
>
> Sorry, but this patch looks completely weird to me. exynos5-dt machine is aimed to
> operate on ANY Exynos5 based board with proper device tree bindings, not only SMDK5250.
> Please add DT support to platform lcd driver and create required bindings for it
> instead of hardcoding the platform data and gpio numbers in mach-exynos5-dt.c
>
Yes true, that GPIO numbers will vary for boards.
Can you please confirm that platform lcd driver means the core
"drivers/video/backlight/platform_lcd.c" file.
But platform lcd driver is used by other(non samsung) platforms also.
So, If I add the DT suppot to that file, I have to test the changes on
other platforms also.
Can you please kindly suggest me some other way to overcome this situation.
Best Wishes,
Leela Krishna Amudala.
> Best regards
> --
> Marek Szyprowski
> Samsung Poland R&D Center
>
>
>
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