@@ -29,6 +29,14 @@ config DRM_DISPLAY_HDMI_HELPER
help
DRM display helpers for HDMI.
+config DRM_DISPLAY_DP_TYPEC_HELPER
+ def_bool y
+ depends on DRM_DISPLAY_HELPER
+ depends on DRM_DISPLAY_HELPER=TYPEC || TYPEC=y
+ help
+ Choose this option to enable helpers for registering USB Type-C
+ switches when USB Type-C DisplayPort Alternate mode is used.
+
config DRM_DP_AUX_CHARDEV
bool "DRM DP AUX Interface"
depends on DRM && DRM_DISPLAY_HELPER
@@ -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 \
new file mode 100644
@@ -0,0 +1,107 @@
+// 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];
+ 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), "%s-%u", dev_name(dev), port_num);
+ 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.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+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(*switch_desc->typec_ports),
+ 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);
@@ -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;
+ struct fwnode_handle *fwnode;
+ void *data;
+ int port_num;
+};
+
+struct drm_dp_typec_switch_desc {
+ struct drm_dp_typec_port_data *typec_ports;
+ int num_typec_switches;
+};
+
+#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_ */
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@chromium.org> --- Changes in v15: - Change the struct definition order for the Type-C switch helpers - Fix style issues - Updated the docs for the return value - Updated the description in Kconfig - Use dev_name as the typec_mux name Changes in v14: - Introduce a new Kconfig because 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 | 107 ++++++++++++++++++ include/drm/display/drm_dp_helper.h | 46 ++++++++ 4 files changed, 163 insertions(+) create mode 100644 drivers/gpu/drm/display/drm_dp_typec_helper.c