diff options
author | Andrew Bresticker <abrestic@chromium.org> | 2014-04-22 04:09:10 +0530 |
---|---|---|
committer | Inki Dae <daeinki@gmail.com> | 2014-06-02 02:07:05 +0900 |
commit | b8b52471e87a713e61d26fa2f546fda0fb04e8fd (patch) | |
tree | e9bdacf10aec08ea529220fbe76c43c0a2e1535f /drivers/gpu/drm/exynos | |
parent | fbc2063d7b76d58e47a74b845148b3a9db052f16 (diff) | |
download | linux-b8b52471e87a713e61d26fa2f546fda0fb04e8fd.tar.bz2 |
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')
-rw-r--r-- | drivers/gpu/drm/exynos/exynos_dp_core.c | 32 | ||||
-rw-r--r-- | drivers/gpu/drm/exynos/exynos_dp_core.h | 1 | ||||
-rw-r--r-- | drivers/gpu/drm/exynos/exynos_dp_reg.c | 44 |
3 files changed, 62 insertions, 15 deletions
diff --git a/drivers/gpu/drm/exynos/exynos_dp_core.c b/drivers/gpu/drm/exynos/exynos_dp_core.c index 1f8914b44714..2b30c55ab050 100644 --- a/drivers/gpu/drm/exynos/exynos_dp_core.c +++ b/drivers/gpu/drm/exynos/exynos_dp_core.c @@ -18,6 +18,8 @@ #include <linux/interrupt.h> #include <linux/delay.h> #include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/gpio.h> #include <linux/component.h> #include <linux/phy/phy.h> #include <video/of_display_timing.h> @@ -1217,6 +1219,7 @@ static int exynos_dp_bind(struct device *dev, struct device *master, void *data) struct drm_device *drm_dev = data; struct resource *res; struct exynos_dp_device *dp; + unsigned int irq_flags; int ret = 0; @@ -1254,7 +1257,30 @@ static int exynos_dp_bind(struct device *dev, struct device *master, void *data) if (IS_ERR(dp->reg_base)) return PTR_ERR(dp->reg_base); - dp->irq = platform_get_irq(pdev, 0); + dp->hpd_gpio = of_get_named_gpio(dev->of_node, "samsung,hpd-gpio", 0); + + if (gpio_is_valid(dp->hpd_gpio)) { + /* + * Set up the hotplug GPIO from the device tree as an interrupt. + * Simply specifying a different interrupt in the device tree + * doesn't work since we handle hotplug rather differently when + * using a GPIO. We also need the actual GPIO specifier so + * that we can get the current state of the GPIO. + */ + ret = devm_gpio_request_one(&pdev->dev, dp->hpd_gpio, GPIOF_IN, + "hpd_gpio"); + if (ret) { + dev_err(&pdev->dev, "failed to get hpd gpio\n"); + return ret; + } + dp->irq = gpio_to_irq(dp->hpd_gpio); + irq_flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; + } else { + dp->hpd_gpio = -ENODEV; + dp->irq = platform_get_irq(pdev, 0); + irq_flags = 0; + } + if (dp->irq == -ENXIO) { dev_err(&pdev->dev, "failed to get irq\n"); return -ENODEV; @@ -1266,8 +1292,8 @@ static int exynos_dp_bind(struct device *dev, struct device *master, void *data) exynos_dp_init_dp(dp); - ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler, 0, - "exynos-dp", dp); + ret = devm_request_irq(&pdev->dev, dp->irq, exynos_dp_irq_handler, + irq_flags, "exynos-dp", dp); if (ret) { dev_err(&pdev->dev, "failed to request irq\n"); return ret; diff --git a/drivers/gpu/drm/exynos/exynos_dp_core.h b/drivers/gpu/drm/exynos/exynos_dp_core.h index d6a900d4ee40..56fa43eb7133 100644 --- a/drivers/gpu/drm/exynos/exynos_dp_core.h +++ b/drivers/gpu/drm/exynos/exynos_dp_core.h @@ -159,6 +159,7 @@ struct exynos_dp_device { struct work_struct hotplug_work; struct phy *phy; int dpms_mode; + int hpd_gpio; struct exynos_drm_panel_info panel; }; 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; } |