| Message ID | 20231103230414.1483428-5-dmitry.baryshkov@linaro.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | drm: simplify support for transparent DRM bridges | expand |
On 04/11/2023 00:03, Dmitry Baryshkov wrote: > Several USB-C controllers implement a pretty simple DRM bridge which > implements just the HPD notification operations. Add special helper > for creating such simple bridges. > > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> > --- > drivers/gpu/drm/bridge/Kconfig | 8 ++ > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/aux-hpd-bridge.c | 164 ++++++++++++++++++++++++ > include/drm/bridge/aux-bridge.h | 18 +++ > 4 files changed, 191 insertions(+) > create mode 100644 drivers/gpu/drm/bridge/aux-hpd-bridge.c > > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig > index f12eab62799f..19d2dc05c397 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -21,6 +21,14 @@ config DRM_AUX_BRIDGE > Simple transparent bridge that is used by several non-DRM drivers to > build bridges chain. > > +config DRM_AUX_HPD_BRIDGE > + tristate > + depends on DRM_BRIDGE && OF > + select AUXILIARY_BUS > + help > + Simple bridge that terminates the bridge chain and provides HPD > + support. > + > menu "Display Interface Bridges" > depends on DRM && DRM_BRIDGE > > diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile > index 918e3bfff079..017b5832733b 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -1,5 +1,6 @@ > # SPDX-License-Identifier: GPL-2.0 > obj-$(CONFIG_DRM_AUX_BRIDGE) += aux-bridge.o > +obj-$(CONFIG_DRM_AUX_HPD_BRIDGE) += aux-hpd-bridge.o > obj-$(CONFIG_DRM_CHIPONE_ICN6211) += chipone-icn6211.o > obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o > obj-$(CONFIG_DRM_CROS_EC_ANX7688) += cros-ec-anx7688.o > diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c > new file mode 100644 > index 000000000000..4defac8ec63f > --- /dev/null > +++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c > @@ -0,0 +1,164 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Copyright (C) 2023 Linaro Ltd. > + * > + * Author: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> > + */ > +#include <linux/auxiliary_bus.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > + > +#include <drm/drm_bridge.h> > +#include <drm/bridge/aux-bridge.h> > + > +static DEFINE_IDA(drm_aux_hpd_bridge_ida); > + > +struct drm_aux_hpd_bridge_data { > + struct drm_bridge bridge; > + struct device *dev; > +}; > + > +static void drm_aux_hpd_bridge_release(struct device *dev) > +{ > + struct auxiliary_device *adev = to_auxiliary_dev(dev); > + > + ida_free(&drm_aux_hpd_bridge_ida, adev->id); > + > + of_node_put(adev->dev.platform_data); > + > + kfree(adev); > +} > + > +static void drm_aux_hpd_bridge_unregister_adev(void *_adev) > +{ > + struct auxiliary_device *adev = _adev; > + > + auxiliary_device_delete(adev); > + auxiliary_device_uninit(adev); > +} > + > +/** > + * drm_dp_hpd_bridge_register - Create a simple HPD DisplayPort bridge > + * @parent: device instance providing this bridge > + * @np: device node pointer corresponding to this bridge instance > + * > + * Creates a simple DRM bridge with the type set to > + * DRM_MODE_CONNECTOR_DisplayPort, which terminates the bridge chain and is > + * able to send the HPD events. > + * > + * Return: device instance that will handle created bridge or an error code > + * encoded into the pointer. > + */ > +struct device *drm_dp_hpd_bridge_register(struct device *parent, > + struct device_node *np) > +{ > + struct auxiliary_device *adev; > + int ret; > + > + adev = kzalloc(sizeof(*adev), GFP_KERNEL); > + if (!adev) > + return ERR_PTR(-ENOMEM); > + > + ret = ida_alloc(&drm_aux_hpd_bridge_ida, GFP_KERNEL); > + if (ret < 0) { > + kfree(adev); > + return ERR_PTR(ret); > + } > + > + adev->id = ret; > + adev->name = "dp_hpd_bridge"; > + adev->dev.parent = parent; > + adev->dev.of_node = parent->of_node; > + adev->dev.release = drm_aux_hpd_bridge_release; > + adev->dev.platform_data = np; > + > + ret = auxiliary_device_init(adev); > + if (ret) { > + ida_free(&drm_aux_hpd_bridge_ida, adev->id); > + kfree(adev); > + return ERR_PTR(ret); > + } > + > + ret = auxiliary_device_add(adev); > + if (ret) { > + auxiliary_device_uninit(adev); > + return ERR_PTR(ret); > + } > + > + ret = devm_add_action_or_reset(parent, drm_aux_hpd_bridge_unregister_adev, adev); > + if (ret) > + return ERR_PTR(ret); > + > + return &adev->dev; > + > +} > +EXPORT_SYMBOL_GPL(drm_dp_hpd_bridge_register); > + > +/** > + * drm_aux_hpd_bridge_notify - notify hot plug detection events > + * @dev: device created for the HPD bridge > + * @status: output connection status > + * > + * A wrapper around drm_bridge_hpd_notify() that is used to report hot plug > + * detection events for bridges created via drm_dp_hpd_bridge_register(). > + * > + * This function shall be called in a context that can sleep. > + */ > +void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status) > +{ > + struct auxiliary_device *adev = to_auxiliary_dev(dev); > + struct drm_aux_hpd_bridge_data *data = auxiliary_get_drvdata(adev); > + > + if (!data) > + return; > + > + drm_bridge_hpd_notify(&data->bridge, status); > +} > +EXPORT_SYMBOL_GPL(drm_aux_hpd_bridge_notify); > + > +static int drm_aux_hpd_bridge_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 drm_aux_hpd_bridge_funcs = { > + .attach = drm_aux_hpd_bridge_attach, > +}; > + > +static int drm_aux_hpd_bridge_probe(struct auxiliary_device *auxdev, > + const struct auxiliary_device_id *id) > +{ > + struct drm_aux_hpd_bridge_data *data; > + > + data = devm_kzalloc(&auxdev->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->dev = &auxdev->dev; > + data->bridge.funcs = &drm_aux_hpd_bridge_funcs; > + data->bridge.of_node = dev_get_platdata(data->dev); > + data->bridge.ops = DRM_BRIDGE_OP_HPD; > + data->bridge.type = id->driver_data; > + > + auxiliary_set_drvdata(auxdev, data); > + > + return devm_drm_bridge_add(data->dev, &data->bridge); > +} > + > +static const struct auxiliary_device_id drm_aux_hpd_bridge_table[] = { > + { .name = KBUILD_MODNAME ".dp_hpd_bridge", .driver_data = DRM_MODE_CONNECTOR_DisplayPort, }, > + {}, > +}; > +MODULE_DEVICE_TABLE(auxiliary, drm_aux_hpd_bridge_table); > + > +static struct auxiliary_driver drm_aux_hpd_bridge_drv = { > + .name = "aux_hpd_bridge", > + .id_table = drm_aux_hpd_bridge_table, > + .probe = drm_aux_hpd_bridge_probe, > +}; > +module_auxiliary_driver(drm_aux_hpd_bridge_drv); > + > +MODULE_AUTHOR("Dmitry Baryshkov <dmitry.baryshkov@linaro.org>"); > +MODULE_DESCRIPTION("DRM HPD bridge"); > +MODULE_LICENSE("GPL"); > diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h > index 441ab3f0e920..33adaf4e4daa 100644 > --- a/include/drm/bridge/aux-bridge.h > +++ b/include/drm/bridge/aux-bridge.h > @@ -7,6 +7,8 @@ > #ifndef DRM_AUX_BRIDGE_H > #define DRM_AUX_BRIDGE_H > > +#include <drm/drm_connector.h> > + > #if IS_ENABLED(CONFIG_DRM_AUX_BRIDGE) > int drm_aux_bridge_register(struct device *parent); > #else > @@ -16,4 +18,20 @@ static inline int drm_aux_bridge_register(struct device *parent) > } > #endif > > +#if IS_ENABLED(CONFIG_DRM_AUX_HPD_BRIDGE) > +struct device *drm_dp_hpd_bridge_register(struct device *parent, > + struct device_node *np); > +void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status); > +#else > +static inline struct device *drm_dp_hpd_bridge_register(struct device *parent, > + struct device_node *np) > +{ > + return 0; > +} > + > +static inline void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status) > +{ > +} > +#endif > + > #endif LGTM: Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index f12eab62799f..19d2dc05c397 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -21,6 +21,14 @@ config DRM_AUX_BRIDGE Simple transparent bridge that is used by several non-DRM drivers to build bridges chain. +config DRM_AUX_HPD_BRIDGE + tristate + depends on DRM_BRIDGE && OF + select AUXILIARY_BUS + help + Simple bridge that terminates the bridge chain and provides HPD + support. + menu "Display Interface Bridges" depends on DRM && DRM_BRIDGE diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 918e3bfff079..017b5832733b 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_DRM_AUX_BRIDGE) += aux-bridge.o +obj-$(CONFIG_DRM_AUX_HPD_BRIDGE) += aux-hpd-bridge.o obj-$(CONFIG_DRM_CHIPONE_ICN6211) += chipone-icn6211.o obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o obj-$(CONFIG_DRM_CROS_EC_ANX7688) += cros-ec-anx7688.o diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c new file mode 100644 index 000000000000..4defac8ec63f --- /dev/null +++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2023 Linaro Ltd. + * + * Author: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> + */ +#include <linux/auxiliary_bus.h> +#include <linux/module.h> +#include <linux/of_device.h> + +#include <drm/drm_bridge.h> +#include <drm/bridge/aux-bridge.h> + +static DEFINE_IDA(drm_aux_hpd_bridge_ida); + +struct drm_aux_hpd_bridge_data { + struct drm_bridge bridge; + struct device *dev; +}; + +static void drm_aux_hpd_bridge_release(struct device *dev) +{ + struct auxiliary_device *adev = to_auxiliary_dev(dev); + + ida_free(&drm_aux_hpd_bridge_ida, adev->id); + + of_node_put(adev->dev.platform_data); + + kfree(adev); +} + +static void drm_aux_hpd_bridge_unregister_adev(void *_adev) +{ + struct auxiliary_device *adev = _adev; + + auxiliary_device_delete(adev); + auxiliary_device_uninit(adev); +} + +/** + * drm_dp_hpd_bridge_register - Create a simple HPD DisplayPort bridge + * @parent: device instance providing this bridge + * @np: device node pointer corresponding to this bridge instance + * + * Creates a simple DRM bridge with the type set to + * DRM_MODE_CONNECTOR_DisplayPort, which terminates the bridge chain and is + * able to send the HPD events. + * + * Return: device instance that will handle created bridge or an error code + * encoded into the pointer. + */ +struct device *drm_dp_hpd_bridge_register(struct device *parent, + struct device_node *np) +{ + struct auxiliary_device *adev; + int ret; + + adev = kzalloc(sizeof(*adev), GFP_KERNEL); + if (!adev) + return ERR_PTR(-ENOMEM); + + ret = ida_alloc(&drm_aux_hpd_bridge_ida, GFP_KERNEL); + if (ret < 0) { + kfree(adev); + return ERR_PTR(ret); + } + + adev->id = ret; + adev->name = "dp_hpd_bridge"; + adev->dev.parent = parent; + adev->dev.of_node = parent->of_node; + adev->dev.release = drm_aux_hpd_bridge_release; + adev->dev.platform_data = np; + + ret = auxiliary_device_init(adev); + if (ret) { + ida_free(&drm_aux_hpd_bridge_ida, adev->id); + kfree(adev); + return ERR_PTR(ret); + } + + ret = auxiliary_device_add(adev); + if (ret) { + auxiliary_device_uninit(adev); + return ERR_PTR(ret); + } + + ret = devm_add_action_or_reset(parent, drm_aux_hpd_bridge_unregister_adev, adev); + if (ret) + return ERR_PTR(ret); + + return &adev->dev; + +} +EXPORT_SYMBOL_GPL(drm_dp_hpd_bridge_register); + +/** + * drm_aux_hpd_bridge_notify - notify hot plug detection events + * @dev: device created for the HPD bridge + * @status: output connection status + * + * A wrapper around drm_bridge_hpd_notify() that is used to report hot plug + * detection events for bridges created via drm_dp_hpd_bridge_register(). + * + * This function shall be called in a context that can sleep. + */ +void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status) +{ + struct auxiliary_device *adev = to_auxiliary_dev(dev); + struct drm_aux_hpd_bridge_data *data = auxiliary_get_drvdata(adev); + + if (!data) + return; + + drm_bridge_hpd_notify(&data->bridge, status); +} +EXPORT_SYMBOL_GPL(drm_aux_hpd_bridge_notify); + +static int drm_aux_hpd_bridge_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 drm_aux_hpd_bridge_funcs = { + .attach = drm_aux_hpd_bridge_attach, +}; + +static int drm_aux_hpd_bridge_probe(struct auxiliary_device *auxdev, + const struct auxiliary_device_id *id) +{ + struct drm_aux_hpd_bridge_data *data; + + data = devm_kzalloc(&auxdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->dev = &auxdev->dev; + data->bridge.funcs = &drm_aux_hpd_bridge_funcs; + data->bridge.of_node = dev_get_platdata(data->dev); + data->bridge.ops = DRM_BRIDGE_OP_HPD; + data->bridge.type = id->driver_data; + + auxiliary_set_drvdata(auxdev, data); + + return devm_drm_bridge_add(data->dev, &data->bridge); +} + +static const struct auxiliary_device_id drm_aux_hpd_bridge_table[] = { + { .name = KBUILD_MODNAME ".dp_hpd_bridge", .driver_data = DRM_MODE_CONNECTOR_DisplayPort, }, + {}, +}; +MODULE_DEVICE_TABLE(auxiliary, drm_aux_hpd_bridge_table); + +static struct auxiliary_driver drm_aux_hpd_bridge_drv = { + .name = "aux_hpd_bridge", + .id_table = drm_aux_hpd_bridge_table, + .probe = drm_aux_hpd_bridge_probe, +}; +module_auxiliary_driver(drm_aux_hpd_bridge_drv); + +MODULE_AUTHOR("Dmitry Baryshkov <dmitry.baryshkov@linaro.org>"); +MODULE_DESCRIPTION("DRM HPD bridge"); +MODULE_LICENSE("GPL"); diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h index 441ab3f0e920..33adaf4e4daa 100644 --- a/include/drm/bridge/aux-bridge.h +++ b/include/drm/bridge/aux-bridge.h @@ -7,6 +7,8 @@ #ifndef DRM_AUX_BRIDGE_H #define DRM_AUX_BRIDGE_H +#include <drm/drm_connector.h> + #if IS_ENABLED(CONFIG_DRM_AUX_BRIDGE) int drm_aux_bridge_register(struct device *parent); #else @@ -16,4 +18,20 @@ static inline int drm_aux_bridge_register(struct device *parent) } #endif +#if IS_ENABLED(CONFIG_DRM_AUX_HPD_BRIDGE) +struct device *drm_dp_hpd_bridge_register(struct device *parent, + struct device_node *np); +void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status); +#else +static inline struct device *drm_dp_hpd_bridge_register(struct device *parent, + struct device_node *np) +{ + return 0; +} + +static inline void drm_aux_hpd_bridge_notify(struct device *dev, enum drm_connector_status status) +{ +} +#endif + #endif
Several USB-C controllers implement a pretty simple DRM bridge which implements just the HPD notification operations. Add special helper for creating such simple bridges. Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> --- drivers/gpu/drm/bridge/Kconfig | 8 ++ drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/aux-hpd-bridge.c | 164 ++++++++++++++++++++++++ include/drm/bridge/aux-bridge.h | 18 +++ 4 files changed, 191 insertions(+) create mode 100644 drivers/gpu/drm/bridge/aux-hpd-bridge.c