On Wed, 22 Mar 2023 at 12:47, Pin-yen Lin <treapking@xxxxxxxxxxxx> wrote: > > Add helpers to register and unregister Type-C "switches" for bridges > capable of switching their output between two downstream devices. > > The helper registers USB Type-C mode switches when the "mode-switch" > and the "reg" properties are available in Device Tree. > > Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx> > > --- > > Changes in v14: > - Introduce a new Kconfig becuase it didn't build when CONFIG_TYPEC=m > - Add comments about devm_* usage > - Fix style issues > > Changes in v13: > - Add typec_mode_switch_node_count helper > - Fix style issues > > Changes in v12: > - Add fwnode_for_each_typec_mode_switch macro > - Remove a duplicated dmesg in the helper > - Used IS_REACHABLE instead to guard the function signatures > > Changes in v11: > - Use fwnode helpers instead of DT > - Moved the helpers to a new file > - Use "reg" instead of "data-lanes" to determine the port number > - Dropped collected tags due to new changes > > Changes in v10: > - Collected Reviewed-by and Tested-by tags > - Replaced "void *" with "typec_mux_set_fn_t" for mux_set callbacks > - Print out the node name when errors on parsing DT > - Use dev_dbg instead of dev_warn when no Type-C switch nodes available > - Made the return path of drm_dp_register_mode_switch clearer > > Changes in v8: > - Fixed the build issue when CONFIG_TYPEC=m > - Fixed some style issues > > Changes in v7: > - Extracted the common codes to a helper function > - New in v7 > > drivers/gpu/drm/display/Kconfig | 8 ++ > drivers/gpu/drm/display/Makefile | 2 + > drivers/gpu/drm/display/drm_dp_typec_helper.c | 105 ++++++++++++++++++ > include/drm/display/drm_dp_helper.h | 46 ++++++++ > 4 files changed, 161 insertions(+) > create mode 100644 drivers/gpu/drm/display/drm_dp_typec_helper.c > > diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig > index 09712b88a5b8..d61076947a1c 100644 > --- a/drivers/gpu/drm/display/Kconfig > +++ b/drivers/gpu/drm/display/Kconfig > @@ -29,6 +29,14 @@ config DRM_DISPLAY_HDMI_HELPER > help > DRM display helpers for HDMI. > > +config DRM_DISPLAY_DP_TYPEC_HELPER > + bool > + default y > + depends on DRM_DISPLAY_HELPER > + depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y If it is a select'able option, it doesn't make sense to use "depends" here. Select will override depends. > + help > + DRM display helpers for USB Type-C Displayport Alternate mode. > + > config DRM_DP_AUX_CHARDEV > bool "DRM DP AUX Interface" > depends on DRM && DRM_DISPLAY_HELPER > diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile > index 17ac4a1006a8..2202a6aea38e 100644 > --- a/drivers/gpu/drm/display/Makefile > +++ b/drivers/gpu/drm/display/Makefile > @@ -8,6 +8,8 @@ drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_HELPER) += \ > drm_dp_helper.o \ > drm_dp_mst_topology.o \ > drm_dsc_helper.o > +drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER) += \ > + drm_dp_typec_helper.o > drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o > drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += \ > drm_hdmi_helper.o \ > diff --git a/drivers/gpu/drm/display/drm_dp_typec_helper.c b/drivers/gpu/drm/display/drm_dp_typec_helper.c > new file mode 100644 > index 000000000000..1562a9ccdaf2 > --- /dev/null > +++ b/drivers/gpu/drm/display/drm_dp_typec_helper.c > @@ -0,0 +1,105 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <linux/usb/typec_mux.h> > +#include <drm/display/drm_dp_helper.h> > + > +static int drm_dp_register_mode_switch(struct device *dev, > + struct fwnode_handle *fwnode, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set) > +{ > + struct drm_dp_typec_port_data *port_data; > + struct typec_mux_desc mux_desc = {}; > + char name[32]; Why 32? > + u32 port_num; > + int ret; > + > + ret = fwnode_property_read_u32(fwnode, "reg", &port_num); > + if (ret) { > + dev_err(dev, "Failed to read reg property: %d\n", ret); > + return ret; > + } > + > + port_data = &switch_desc->typec_ports[port_num]; > + port_data->data = data; > + port_data->port_num = port_num; > + port_data->fwnode = fwnode; > + mux_desc.fwnode = fwnode; > + mux_desc.drvdata = port_data; > + snprintf(name, sizeof(name), "%pfwP-%u", fwnode, port_num); I think it makes more sense to use dev_name here instead of fwnode. > + mux_desc.name = name; > + mux_desc.set = mux_set; > + > + port_data->typec_mux = typec_mux_register(dev, &mux_desc); > + ret = PTR_ERR_OR_ZERO(port_data->typec_mux); > + if (ret) > + dev_err(dev, "Mode switch register for port %d failed: %d\n", > + port_num, ret); > + > + return ret; > +} > + > +/** > + * drm_dp_register_typec_switches() - register Type-C switches > + * @dev: Device that registers Type-C switches > + * @port: Device node for the switch > + * @switch_desc: A Type-C switch descriptor > + * @data: Private data for the switches > + * @mux_set: Callback function for typec_mux_set > + * > + * This function registers USB Type-C switches for DP bridges that can switch > + * the output signal between their output pins. This function uses devm_kcalloc > + * to allocate memory, so it is expected to only call this in the driver probe > + * functions. > + * > + * Currently only mode switches are implemented, and the function assumes the > + * given @port device node has endpoints with "mode-switch" property. > + * The port number is determined by the "reg" property of the endpoint. > + */ > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set) > +{ > + struct fwnode_handle *sw; > + int ret; > + > + switch_desc->num_typec_switches = typec_mode_switch_node_count(port); > + if (!switch_desc->num_typec_switches) { > + dev_dbg(dev, "No Type-C switches node found\n"); > + return 0; > + } > + > + switch_desc->typec_ports = devm_kcalloc(dev, switch_desc->num_typec_switches, > + sizeof(struct drm_dp_typec_port_data), > + GFP_KERNEL); > + if (!switch_desc->typec_ports) > + return -ENOMEM; > + > + /* Register switches for each connector. */ > + for_each_typec_mode_switch_node(port, sw) { > + ret = drm_dp_register_mode_switch(dev, sw, switch_desc, data, mux_set); > + if (ret) > + goto err_unregister_typec_switches; > + } > + > + return 0; > + > +err_unregister_typec_switches: > + fwnode_handle_put(sw); > + drm_dp_unregister_typec_switches(switch_desc); > + return ret; > +} > +EXPORT_SYMBOL(drm_dp_register_typec_switches); > + > +/** > + * drm_dp_unregister_typec_switches() - unregister Type-C switches > + * @switch_desc: A Type-C switch descriptor > + */ > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > +{ > + unsigned int i; > + > + for (i = 0; i < switch_desc->num_typec_switches; i++) > + typec_mux_unregister(switch_desc->typec_ports[i].typec_mux); > +} > +EXPORT_SYMBOL(drm_dp_unregister_typec_switches); > diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h > index ab55453f2d2c..0fe56586d7bc 100644 > --- a/include/drm/display/drm_dp_helper.h > +++ b/include/drm/display/drm_dp_helper.h > @@ -25,6 +25,7 @@ > > #include <linux/delay.h> > #include <linux/i2c.h> > +#include <linux/usb/typec_mux.h> > > #include <drm/display/drm_dp.h> > #include <drm/drm_connector.h> > @@ -763,4 +764,49 @@ bool drm_dp_downstream_rgb_to_ycbcr_conversion(const u8 dpcd[DP_RECEIVER_CAP_SIZ > const u8 port_cap[4], u8 color_spc); > int drm_dp_pcon_convert_rgb_to_ycbcr(struct drm_dp_aux *aux, u8 color_spc); > > +struct drm_dp_typec_port_data { > + struct typec_mux_dev *typec_mux; > + int port_num; > + struct fwnode_handle *fwnode; > + void *data; > +}; > + > +struct drm_dp_typec_switch_desc { > + int num_typec_switches; > + struct drm_dp_typec_port_data *typec_ports; > +}; > + > +#define for_each_typec_mode_switch_node(port, sw) \ > + fwnode_for_each_child_node((port), (sw)) \ > + for_each_if(fwnode_property_present((sw), "mode-switch")) > + > +static inline unsigned int typec_mode_switch_node_count(struct fwnode_handle *port) > +{ > + struct fwnode_handle *sw; > + unsigned int count = 0; > + > + for_each_typec_mode_switch_node(port, sw) > + count++; > + > + return count; > +} > + > +#ifdef CONFIG_DRM_DISPLAY_DP_TYPEC_HELPER > +void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc); > +int drm_dp_register_typec_switches(struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, > + void *data, typec_mux_set_fn_t mux_set); > +#else > +static inline void drm_dp_unregister_typec_switches(struct drm_dp_typec_switch_desc *switch_desc) > +{ > +} > +static inline int drm_dp_register_typec_switches( > + struct device *dev, struct fwnode_handle *port, > + struct drm_dp_typec_switch_desc *switch_desc, void *data, > + typec_mux_set_fn_t mux_set) > +{ > + return -EOPNOTSUPP; > +} > +#endif > + > #endif /* _DRM_DP_HELPER_H_ */ > -- > 2.40.0.rc1.284.g88254d51c5-goog > -- With best wishes Dmitry