From mboxrd@z Thu Jan 1 00:00:00 1970 From: robherring2@gmail.com (Rob Herring) Date: Wed, 2 Sep 2015 15:17:57 -0500 Subject: [PATCH v4 14/16] drm: bridge: analogix/dp: try force hpd after plug in lookup failed In-Reply-To: <1441088079-25809-1-git-send-email-ykk@rock-chips.com> References: <1441086371-24838-1-git-send-email-ykk@rock-chips.com> <1441088079-25809-1-git-send-email-ykk@rock-chips.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Sep 1, 2015 at 1:14 AM, Yakir Yang wrote: > Some edp screen do not have hpd signal, so we can't just return > failed when hpd plug in detect failed. This is a property of the panel (or connector perhaps), so this property should be located there. At least, it is a common issue and not specific to this chip. We could have an HDMI connector and failed to hook up HPD for example. A connector node is also where hpd-gpios should be located instead (and are already defined by ../bindings/video/hdmi-connector.txt). Perhaps we need a eDP connector binding, too. Are there any eDP panels which don't have EDID and need panel details in DT? Rob > This is an hardware property, so we need add a devicetree property > "analogix,need-force-hpd" to indicate this sutiation. > > Signed-off-by: Yakir Yang > --- > Changes in v4: None > Changes in v3: > - Add "analogix,need-force-hpd" to indicate whether driver need foce > hpd when hpd detect failed. > > Changes in v2: None > > .../devicetree/bindings/drm/bridge/analogix_dp.txt | 4 ++- > .../bindings/video/analogix_dp-rockchip.txt | 1 + > .../devicetree/bindings/video/exynos_dp.txt | 1 + > drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 36 +++++++++++++++++++--- > drivers/gpu/drm/bridge/analogix/analogix_dp_core.h | 2 ++ > drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 9 ++++++ > 6 files changed, 47 insertions(+), 6 deletions(-) > > diff --git a/Documentation/devicetree/bindings/drm/bridge/analogix_dp.txt b/Documentation/devicetree/bindings/drm/bridge/analogix_dp.txt > index f54dc3e..c310367 100644 > --- a/Documentation/devicetree/bindings/drm/bridge/analogix_dp.txt > +++ b/Documentation/devicetree/bindings/drm/bridge/analogix_dp.txt > @@ -22,6 +22,9 @@ Required properties for dp-controller: > from general PHY binding: Should be "dp". > > Optional properties for dp-controller: > + -analogix,need-force-hpd: > + Indicate driver need force hpd when hpd detect failed, this > + is used for some eDP screen which don't have hpd signal. > -hpd-gpios: > Hotplug detect GPIO. > Indicates which GPIO should be used for hotplug detection > @@ -31,7 +34,6 @@ Optional properties for dp-controller: > * Documentation/devicetree/bindings/video/exynos_dp.txt > * Documentation/devicetree/bindings/video/analogix_dp-rockchip.txt > > - > [1]: Documentation/devicetree/bindings/media/video-interfaces.txt > ------------------------------------------------------------------------------- > > diff --git a/Documentation/devicetree/bindings/video/analogix_dp-rockchip.txt b/Documentation/devicetree/bindings/video/analogix_dp-rockchip.txt > index 502483e..8b9ed7d 100644 > --- a/Documentation/devicetree/bindings/video/analogix_dp-rockchip.txt > +++ b/Documentation/devicetree/bindings/video/analogix_dp-rockchip.txt > @@ -28,6 +28,7 @@ For the below properties, please refer to Analogix DP binding document: > - phys (required) > - phy-names (required) > - hpd-gpios (optional) > +- analogix,need-force-hpd (optional) > ------------------------------------------------------------------------------- > > Example: > diff --git a/Documentation/devicetree/bindings/video/exynos_dp.txt b/Documentation/devicetree/bindings/video/exynos_dp.txt > index ea03b3a..4f06e80 100644 > --- a/Documentation/devicetree/bindings/video/exynos_dp.txt > +++ b/Documentation/devicetree/bindings/video/exynos_dp.txt > @@ -41,6 +41,7 @@ For the below properties, please refer to Analogix DP binding document: > -phys (required) > -phy-names (required) > -hpd-gpios (optional) > + -analogix,need-force-hpd (optional) > -video interfaces (optional) > > Deprecated properties for DisplayPort: > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > index f7227ec..e6b328a 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c > @@ -63,15 +63,38 @@ static int analogix_dp_detect_hpd(struct analogix_dp_device *dp) > { > int timeout_loop = 0; > > - while (analogix_dp_get_plug_in_status(dp) != 0) { > + while (timeout_loop < DP_TIMEOUT_LOOP_COUNT) { > + if (analogix_dp_get_plug_in_status(dp) == 0) > + return 0; > + > timeout_loop++; > - if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) { > - dev_err(dp->dev, "failed to get hpd plug status\n"); > - return -ETIMEDOUT; > - } > usleep_range(10, 11); > } > > + /* > + * Some edp screen do not have hpd signal, so we can't just > + * return failed when hpd plug in detect failed, DT property > + * "need-force-hpd" would indicate whether driver need this. > + */ > + if (!dp->need_force_hpd) > + return -ETIMEDOUT; > + > + /* > + * The eDP TRM indicate that if HPD_STATUS(RO) is 0, AUX CH > + * will not work, so we need to give a force hpd action to > + * set HPD_STATUS manually. > + */ > + dev_dbg(dp->dev, "failed to get hpd plug status, try to force hpd\n"); > + > + analogix_dp_force_hpd(dp); > + > + if (analogix_dp_get_plug_in_status(dp) != 0) { > + dev_err(dp->dev, "failed to get hpd plug in status\n"); > + return -EINVAL; > + } > + > + dev_dbg(dp->dev, "success to get plug in status after force hpd\n"); > + > return 0; > } > > @@ -1287,6 +1310,9 @@ int analogix_dp_bind(struct device *dev, struct drm_device *drm_dev, > if (IS_ERR(dp->reg_base)) > return PTR_ERR(dp->reg_base); > > + dp->need_force_hpd = > + of_property_read_bool(dev->of_node, "analogix,need-force-hpd"); > + > dp->hpd_gpio = of_get_named_gpio(dev->of_node, "hpd-gpios", 0); > if (gpio_is_valid(dp->hpd_gpio)) > dp->hpd_gpio = of_get_named_gpio(dev->of_node, > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h > index d8945e2..6960ab3 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h > @@ -160,6 +160,7 @@ struct analogix_dp_device { > struct phy *phy; > int dpms_mode; > int hpd_gpio; > + bool need_force_hpd; > > struct analogix_dp_plat_data *plat_data; > }; > @@ -180,6 +181,7 @@ void analogix_dp_set_analog_power_down(struct analogix_dp_device *dp, > bool enable); > void analogix_dp_init_analog_func(struct analogix_dp_device *dp); > void analogix_dp_init_hpd(struct analogix_dp_device *dp); > +void analogix_dp_force_hpd(struct analogix_dp_device *dp); > enum dp_irq_type analogix_dp_get_irq_type(struct analogix_dp_device *dp); > void analogix_dp_clear_hotplug_interrupts(struct analogix_dp_device *dp); > void analogix_dp_reset_aux(struct analogix_dp_device *dp); > diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c > index 15346fe..3086afc 100644 > --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c > +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c > @@ -365,6 +365,15 @@ void analogix_dp_init_hpd(struct analogix_dp_device *dp) > writel(reg, dp->reg_base + ANALOGIX_DP_SYS_CTL_3); > } > > +void analogix_dp_force_hpd(struct analogix_dp_device *dp) > +{ > + u32 reg; > + > + reg = readl(dp->reg_base + ANALOGIX_DP_SYS_CTL_3); > + reg = (F_HPD | HPD_CTRL); > + writel(reg, dp->reg_base + ANALOGIX_DP_SYS_CTL_3); > +} > + > enum dp_irq_type analogix_dp_get_irq_type(struct analogix_dp_device *dp) > { > u32 reg; > -- > 2.1.2 > >