Hi Jingoo,
On Fri, Apr 18, 2014 at 1:53 PM, Jingoo Han jg1.han@samsung.com wrote:
On Wednesday, April 16, 2014 11:33 PM, Ajay Kumar wrote:
From: Andrew Bresticker abrestic@chromium.org
Certain bridge chips use a GPIO to indicate the cable status instead of the I_DP_HPD pin. This adds an optional device-tree property, "samsung,hpd-gpio", to the exynos-dp controller which indicates that the specified GPIO should be used for hotplug detection. The GPIO is then set up as an edge-triggered interrupt where the rising edge indicates hotplug-in and the falling edge indicates
hotplug-out.
Signed-off-by: Andrew Bresticker abrestic@chromium.org Signed-off-by: Rahul Sharma rahul.sharma@samsung.com Signed-off-by: Ajay Kumar ajaykumar.rs@samsung.com
.../devicetree/bindings/video/exynos_dp.txt | 4 +++ drivers/gpu/drm/exynos/exynos_dp_core.c | 32
++++++++++++++++++++--
drivers/gpu/drm/exynos/exynos_dp_core.h | 1 + drivers/gpu/drm/exynos/exynos_dp_reg.c | 26
++++++++++++++++--
4 files changed, 57 insertions(+), 6 deletions(-)
[.....]
--- a/drivers/gpu/drm/exynos/exynos_dp_reg.c +++ b/drivers/gpu/drm/exynos/exynos_dp_reg.c @@ -13,6 +13,7 @@ #include <linux/device.h> #include <linux/io.h> #include <linux/delay.h> +#include <linux/gpio.h>
#include "exynos_dp_core.h" #include "exynos_dp_reg.h" @@ -326,6 +327,9 @@ void exynos_dp_clear_hotplug_interrupts(struct
exynos_dp_device *dp)
{ u32 reg;
if (gpio_is_valid(dp->hpd_gpio))return;reg = HOTPLUG_CHG | HPD_LOST | PLUG; writel(reg, dp->reg_base + EXYNOS_DP_COMMON_INT_STA_4);@@ -337,6 +341,9 @@ void exynos_dp_init_hpd(struct exynos_dp_device *dp) { u32 reg;
if (gpio_is_valid(dp->hpd_gpio))return;exynos_dp_clear_hotplug_interrupts(dp); reg = readl(dp->reg_base + EXYNOS_DP_SYS_CTL_3);@@ -348,6 +355,14 @@ enum dp_irq_type exynos_dp_get_irq_type(struct
exynos_dp_device *dp)
{ u32 reg;
if (gpio_is_valid(dp->hpd_gpio)) {reg = gpio_get_value(dp->hpd_gpio);if (reg)return DP_IRQ_TYPE_HP_CABLE_IN;elsereturn DP_IRQ_TYPE_HP_CABLE_OUT;}Please keep the style. It enhances the readability.
if (gpio_is_valid(dp->hpd_gpio)) { ... } else { ... }
Ok.
Then, it can be as bellows.
if (gpio_is_valid(dp->hpd_gpio)) {reg = gpio_get_value(dp->hpd_gpio);if (reg)return DP_IRQ_TYPE_HP_CABLE_IN;elsereturn DP_IRQ_TYPE_HP_CABLE_OUT;} else {/* Parse hotplug interrupt status register */reg = readl(dp->reg_base + EXYNOS_DP_COMMON_INT_STA_4);if (reg & PLUG)return DP_IRQ_TYPE_HP_CABLE_IN;if (reg & HPD_LOST)return DP_IRQ_TYPE_HP_CABLE_OUT;if (reg & HOTPLUG_CHG)return DP_IRQ_TYPE_HP_CHANGE;}Will change this.
return DP_IRQ_TYPE_UNKNOWN;}
Best regards, Jingoo Han
/* Parse hotplug interrupt status register */ reg = readl(dp->reg_base + EXYNOS_DP_COMMON_INT_STA_4);@@ -402,9 +417,14 @@ int exynos_dp_get_plug_in_status(struct
exynos_dp_device *dp)
{ u32 reg;
reg = readl(dp->reg_base + EXYNOS_DP_SYS_CTL_3);if (reg & HPD_STATUS)return 0;
if (gpio_is_valid(dp->hpd_gpio)) {if (gpio_get_value(dp->hpd_gpio))return 0;} else {reg = readl(dp->reg_base + EXYNOS_DP_SYS_CTL_3);if (reg & HPD_STATUS)return 0;} return -EINVAL;}
1.8.1.2
Thanks and Regrads, Ajay Kumar