diff options
| author | Andrew Bresticker <abrestic@chromium.org> | 2014-04-22 02:39:10 +0400 |
|---|---|---|
| committer | Inki Dae <daeinki@gmail.com> | 2014-06-01 21:07:05 +0400 |
| commit | b8b52471e87a713e61d26fa2f546fda0fb04e8fd (patch) | |
| tree | e9bdacf10aec08ea529220fbe76c43c0a2e1535f /drivers/gpu/drm/exynos/exynos_dp_reg.c | |
| parent | fbc2063d7b76d58e47a74b845148b3a9db052f16 (diff) | |
| download | linux-b8b52471e87a713e61d26fa2f546fda0fb04e8fd.tar.xz | |
drm/exynos: dp: support hotplug detection via GPIO
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>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Diffstat (limited to 'drivers/gpu/drm/exynos/exynos_dp_reg.c')
| -rw-r--r-- | drivers/gpu/drm/exynos/exynos_dp_reg.c | 44 |
1 files changed, 32 insertions, 12 deletions
diff --git a/drivers/gpu/drm/exynos/exynos_dp_reg.c b/drivers/gpu/drm/exynos/exynos_dp_reg.c index b70da5052ff0..79291a2ce50d 100644 --- 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); @@ -348,19 +355,27 @@ enum dp_irq_type exynos_dp_get_irq_type(struct exynos_dp_device *dp) { u32 reg; - /* Parse hotplug interrupt status register */ - reg = readl(dp->reg_base + EXYNOS_DP_COMMON_INT_STA_4); + if (gpio_is_valid(dp->hpd_gpio)) { + reg = gpio_get_value(dp->hpd_gpio); + if (reg) + return DP_IRQ_TYPE_HP_CABLE_IN; + else + return 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 & PLUG) + return DP_IRQ_TYPE_HP_CABLE_IN; - if (reg & HPD_LOST) - return DP_IRQ_TYPE_HP_CABLE_OUT; + if (reg & HPD_LOST) + return DP_IRQ_TYPE_HP_CABLE_OUT; - if (reg & HOTPLUG_CHG) - return DP_IRQ_TYPE_HP_CHANGE; + if (reg & HOTPLUG_CHG) + return DP_IRQ_TYPE_HP_CHANGE; - return DP_IRQ_TYPE_UNKNOWN; + return DP_IRQ_TYPE_UNKNOWN; + } } void exynos_dp_reset_aux(struct exynos_dp_device *dp) @@ -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; } |