Add support for configuring display-port altmode through device-properties.
We could try to add a generic mechanism for describing altmodes in
device-properties, but various altmodes will likely need altmode specific
configuration. E.g. the display-port altmode needs some way to describe
which set of DP pins on the GPU is connected to the USB Type-C connector.
As such it is better to have a separate set of altmode specific properties
per altmode and this commit adds a property for basic display-port altmode
support.
Signed-off-by: Hans de Goede <hdego...@redhat.com>
---
.../bindings/connector/usb-connector.txt | 3 ++
drivers/usb/typec/tcpm/tcpm.c | 33 +++++++++++++++++++
2 files changed, 36 insertions(+)
diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt
b/Documentation/devicetree/bindings/connector/usb-connector.txt
index d357987181ee..7bae3cc9c76a 100644
--- a/Documentation/devicetree/bindings/connector/usb-connector.txt
+++ b/Documentation/devicetree/bindings/connector/usb-connector.txt
@@ -38,6 +38,9 @@ Optional properties for usb-c-connector:
or Try.SRC, should be "sink" for Try.SNK or "source" for Try.SRC.
- data-role: should be one of "host", "device", "dual"(DRD) if typec
connector supports USB data.
+- displayport-vdo: The presenence of this property indicates that the
+ usb-connector supports displayport-altmode (svid 0xff01), the value of
+ this property is an u32 with the vdo value for the displayport-altmode,
Required properties for usb-c-connector with power delivery support:
- source-pdos: An array of u32 with each entry providing supported power
diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index c5fa18759f8e..2e3096657e96 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -28,6 +28,7 @@
#include <linux/usb/role.h>
#include <linux/usb/tcpm.h>
#include <linux/usb/typec_altmode.h>
+#include <linux/usb/typec_dp.h>
#include <linux/workqueue.h>
#define FOREACH_STATE(S) \
@@ -281,6 +282,7 @@ struct tcpm_port {
unsigned int nr_snk_pdo;
u32 snk_vdo[VDO_MAX_OBJECTS];
unsigned int nr_snk_vdo;
+ u32 displayport_vdo;
unsigned int operating_snk_mw;
bool update_sink_caps;
@@ -4433,6 +4435,9 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
port->nr_snk_pdo))
return -EINVAL;
+ fwnode_property_read_u32(fwnode, "displayport-vdo",
+ &port->displayport_vdo);
+
if (fwnode_property_read_u32(fwnode, "op-sink-microwatt", &mw) < 0)
return -EINVAL;
port->operating_snk_mw = mw / 1000;
@@ -4667,6 +4672,28 @@ static int devm_tcpm_psy_register(struct tcpm_port *port)
return PTR_ERR_OR_ZERO(port->psy);
}
+static int tcpm_register_port_altmodes(struct tcpm_port *port)
+{
+ struct typec_altmode_desc desc;
+ struct typec_altmode *alt;
+ int index = 0;
+
+ if (port->displayport_vdo) {
+ desc.svid = USB_TYPEC_DP_SID;
+ desc.mode = USB_TYPEC_DP_MODE;
+ desc.vdo = port->displayport_vdo;
+ alt = typec_port_register_altmode(port->typec_port, &desc);
+ if (IS_ERR(alt))
+ return PTR_ERR(alt);
+ typec_altmode_set_drvdata(alt, port);
+ alt->ops = &tcpm_altmode_ops;
+ port->port_altmode[index] = alt;
+ index++;
+ }
+ /* Future support for further altmodes goes here */
+ return 0;
+}
+
struct tcpm_port *tcpm_register_port(struct device *dev, struct tcpc_dev *tcpc)
{
struct tcpm_port *port;
@@ -4736,6 +4763,10 @@ struct tcpm_port *tcpm_register_port(struct device *dev,
struct tcpc_dev *tcpc)
goto out_role_sw_put;
}
+ err = tcpm_register_port_altmodes(port);
+ if (err)
+ goto out_unregister_port;
+
mutex_lock(&port->lock);
tcpm_init(port);
mutex_unlock(&port->lock);
@@ -4743,6 +4774,8 @@ struct tcpm_port *tcpm_register_port(struct device *dev,
struct tcpc_dev *tcpc)
tcpm_log(port, "%s: registered", dev_name(dev));
return port;
+out_unregister_port:
+ typec_unregister_port(port->typec_port);
out_role_sw_put:
usb_role_switch_put(port->role_sw);
out_destroy_wq:
--
2.23.0
