[v6,6/6] usb: typec: qcom-pmic-typec: switch to DRM_AUX_HPD_BRIDGE

Use the freshly defined DRM_AUX_HPD_BRIDGE instead of open-coding the
same functionality for the DRM bridge chain termination.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/usb/typec/tcpm/Kconfig                |  1 +
 drivers/usb/typec/tcpm/qcom/qcom_pmic_typec.c | 41 +++----------------
 2 files changed, 7 insertions(+), 35 deletions(-)

On 04/11/2023 01:03, Dmitry Baryshkov wrote:
> Use the freshly defined DRM_AUX_HPD_BRIDGE instead of open-coding the
> same functionality for the DRM bridge chain termination.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Greg, Bryan, could you pease ack merging this patch through the drm-misc 
tree together with the rest of the series?

You have acked patch 3, but since that time I added this one.

> ---
>   drivers/usb/typec/tcpm/Kconfig                |  1 +
>   drivers/usb/typec/tcpm/qcom/qcom_pmic_typec.c | 41 +++----------------
>   2 files changed, 7 insertions(+), 35 deletions(-)
> 
> diff --git a/drivers/usb/typec/tcpm/Kconfig b/drivers/usb/typec/tcpm/Kconfig
> index 0b2993fef564..64d5421c69e6 100644
> --- a/drivers/usb/typec/tcpm/Kconfig
> +++ b/drivers/usb/typec/tcpm/Kconfig
> @@ -80,6 +80,7 @@ config TYPEC_QCOM_PMIC
>   	tristate "Qualcomm PMIC USB Type-C Port Controller Manager driver"
>   	depends on ARCH_QCOM || COMPILE_TEST
>   	depends on DRM || DRM=n
> +	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE
>   	help
>   	  A Type-C port and Power Delivery driver which aggregates two
>   	  discrete pieces of silicon in the PM8150b PMIC block: the
> diff --git a/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec.c b/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec.c
> index 581199d37b49..1a2b4bddaa97 100644
> --- a/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec.c
> +++ b/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec.c
> @@ -18,7 +18,7 @@
>   #include <linux/usb/tcpm.h>
>   #include <linux/usb/typec_mux.h>
>   
> -#include <drm/drm_bridge.h>
> +#include <drm/bridge/aux-bridge.h>
>   
>   #include "qcom_pmic_typec_pdphy.h"
>   #include "qcom_pmic_typec_port.h"
> @@ -36,7 +36,6 @@ struct pmic_typec {
>   	struct pmic_typec_port	*pmic_typec_port;
>   	bool			vbus_enabled;
>   	struct mutex		lock;		/* VBUS state serialization */
> -	struct drm_bridge	bridge;
>   };
>   
>   #define tcpc_to_tcpm(_tcpc_) container_of(_tcpc_, struct pmic_typec, tcpc)
> @@ -150,35 +149,6 @@ static int qcom_pmic_typec_init(struct tcpc_dev *tcpc)
>   	return 0;
>   }
>   
> -#if IS_ENABLED(CONFIG_DRM)
> -static int qcom_pmic_typec_attach(struct drm_bridge *bridge,
> -				     enum drm_bridge_attach_flags flags)
> -{
> -	return flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR ? 0 : -EINVAL;
> -}
> -
> -static const struct drm_bridge_funcs qcom_pmic_typec_bridge_funcs = {
> -	.attach = qcom_pmic_typec_attach,
> -};
> -
> -static int qcom_pmic_typec_init_drm(struct pmic_typec *tcpm)
> -{
> -	tcpm->bridge.funcs = &qcom_pmic_typec_bridge_funcs;
> -#ifdef CONFIG_OF
> -	tcpm->bridge.of_node = of_get_child_by_name(tcpm->dev->of_node, "connector");
> -#endif
> -	tcpm->bridge.ops = DRM_BRIDGE_OP_HPD;
> -	tcpm->bridge.type = DRM_MODE_CONNECTOR_DisplayPort;
> -
> -	return devm_drm_bridge_add(tcpm->dev, &tcpm->bridge);
> -}
> -#else
> -static int qcom_pmic_typec_init_drm(struct pmic_typec *tcpm)
> -{
> -	return 0;
> -}
> -#endif
> -
>   static int qcom_pmic_typec_probe(struct platform_device *pdev)
>   {
>   	struct pmic_typec *tcpm;
> @@ -186,6 +156,7 @@ static int qcom_pmic_typec_probe(struct platform_device *pdev)
>   	struct device_node *np = dev->of_node;
>   	const struct pmic_typec_resources *res;
>   	struct regmap *regmap;
> +	struct device *bridge_dev;
>   	u32 base[2];
>   	int ret;
>   
> @@ -241,14 +212,14 @@ static int qcom_pmic_typec_probe(struct platform_device *pdev)
>   	mutex_init(&tcpm->lock);
>   	platform_set_drvdata(pdev, tcpm);
>   
> -	ret = qcom_pmic_typec_init_drm(tcpm);
> -	if (ret)
> -		return ret;
> -
>   	tcpm->tcpc.fwnode = device_get_named_child_node(tcpm->dev, "connector");
>   	if (!tcpm->tcpc.fwnode)
>   		return -EINVAL;
>   
> +	bridge_dev = drm_dp_hpd_bridge_register(tcpm->dev, to_of_node(tcpm->tcpc.fwnode));
> +	if (IS_ERR(bridge_dev))
> +		return PTR_ERR(bridge_dev);
> +
>   	tcpm->tcpm_port = tcpm_register_port(tcpm->dev, &tcpm->tcpc);
>   	if (IS_ERR(tcpm->tcpm_port)) {
>   		ret = PTR_ERR(tcpm->tcpm_port);

On 03/11/2023 23:03, Dmitry Baryshkov wrote:
> Use the freshly defined DRM_AUX_HPD_BRIDGE instead of open-coding the
> same functionality for the DRM bridge chain termination.
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

> +	bridge_dev = drm_dp_hpd_bridge_register(tcpm->dev, to_of_node(tcpm->tcpc.fwnode));
> +	if (IS_ERR(bridge_dev))
> +		return PTR_ERR(bridge_dev);
> +

What is the effect if we never attach any bridged devices ?

We make an aux device that just hangs around and eventually get cleaned 
up on release ? That's the way I read this code anyway.

Acked-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>