#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
+#include "drm_crtc_helper_internal.h"
+
/**
* DOC: dp mst helper
*
int id,
struct drm_dp_payload *payload);
+static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port,
+ int offset, int size, u8 *bytes);
static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port,
int offset, int size, u8 *bytes);
return send_link;
}
+/**
+ * drm_dp_mst_dpcd_read() - read a series of bytes from the DPCD via sideband
+ * @aux: Fake sideband AUX CH
+ * @offset: address of the (first) register to read
+ * @buffer: buffer to store the register values
+ * @size: number of bytes in @buffer
+ *
+ * Performs the same functionality for remote devices via
+ * sideband messaging as drm_dp_dpcd_read() does for local
+ * devices via actual AUX CH.
+ *
+ * Return: Number of bytes read, or negative error code on failure.
+ */
+ssize_t drm_dp_mst_dpcd_read(struct drm_dp_aux *aux,
+ unsigned int offset, void *buffer, size_t size)
+{
+ struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port,
+ aux);
+
+ return drm_dp_send_dpcd_read(port->mgr, port,
+ offset, size, buffer);
+}
+
+/**
+ * drm_dp_mst_dpcd_write() - write a series of bytes to the DPCD via sideband
+ * @aux: Fake sideband AUX CH
+ * @offset: address of the (first) register to write
+ * @buffer: buffer containing the values to write
+ * @size: number of bytes in @buffer
+ *
+ * Performs the same functionality for remote devices via
+ * sideband messaging as drm_dp_dpcd_write() does for local
+ * devices via actual AUX CH.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux,
+ unsigned int offset, void *buffer, size_t size)
+{
+ struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port,
+ aux);
+
+ return drm_dp_send_dpcd_write(port->mgr, port,
+ offset, size, buffer);
+}
+
static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid)
{
int ret;
strlcat(proppath, temp, proppath_size);
}
+/**
+ * drm_dp_mst_connector_late_register() - Late MST connector registration
+ * @connector: The MST connector
+ * @port: The MST port for this connector
+ *
+ * Helper to register the remote aux device for this MST port. Drivers should
+ * call this from their mst connector's late_register hook to enable MST aux
+ * devices.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int drm_dp_mst_connector_late_register(struct drm_connector *connector,
+ struct drm_dp_mst_port *port)
+{
+ DRM_DEBUG_KMS("registering %s remote bus for %s\n",
+ port->aux.name, connector->kdev->kobj.name);
+
+ port->aux.dev = connector->kdev;
+ return drm_dp_aux_register_devnode(&port->aux);
+}
+EXPORT_SYMBOL(drm_dp_mst_connector_late_register);
+
+/**
+ * drm_dp_mst_connector_early_unregister() - Early MST connector unregistration
+ * @connector: The MST connector
+ * @port: The MST port for this connector
+ *
+ * Helper to unregister the remote aux device for this MST port, registered by
+ * drm_dp_mst_connector_late_register(). Drivers should call this from their mst
+ * connector's early_unregister hook.
+ */
+void drm_dp_mst_connector_early_unregister(struct drm_connector *connector,
+ struct drm_dp_mst_port *port)
+{
+ DRM_DEBUG_KMS("unregistering %s remote bus for %s\n",
+ port->aux.name, connector->kdev->kobj.name);
+ drm_dp_aux_unregister_devnode(&port->aux);
+}
+EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister);
+
static void drm_dp_add_port(struct drm_dp_mst_branch *mstb,
struct drm_device *dev,
struct drm_dp_link_addr_reply_port *port_msg)
port->mgr = mstb->mgr;
port->aux.name = "DPMST";
port->aux.dev = dev->dev;
+ port->aux.is_remote = true;
/*
* Make sure the memory allocation for our parent branch stays
return false;
}
-#if 0
static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes)
{
struct drm_dp_sideband_msg_req_body req;
return 0;
}
-#endif
static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr,
bool up, u8 *msg, int len)
}
EXPORT_SYMBOL(drm_dp_update_payload_part2);
-#if 0 /* unused as of yet */
static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port,
- int offset, int size)
+ int offset, int size, u8 *bytes)
{
int len;
+ int ret = 0;
struct drm_dp_sideband_msg_tx *txmsg;
+ struct drm_dp_mst_branch *mstb;
+
+ mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent);
+ if (!mstb)
+ return -EINVAL;
txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
- if (!txmsg)
- return -ENOMEM;
+ if (!txmsg) {
+ ret = -ENOMEM;
+ goto fail_put;
+ }
- len = build_dpcd_read(txmsg, port->port_num, 0, 8);
+ len = build_dpcd_read(txmsg, port->port_num, offset, size);
txmsg->dst = port->parent;
drm_dp_queue_down_tx(mgr, txmsg);
- return 0;
+ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
+ if (ret < 0)
+ goto fail_free;
+
+ /* DPCD read should never be NACKed */
+ if (txmsg->reply.reply_type == 1) {
+ DRM_ERROR("mstb %p port %d: DPCD read on addr 0x%x for %d bytes NAKed\n",
+ mstb, port->port_num, offset, size);
+ ret = -EIO;
+ goto fail_free;
+ }
+
+ if (txmsg->reply.u.remote_dpcd_read_ack.num_bytes != size) {
+ ret = -EPROTO;
+ goto fail_free;
+ }
+
+ ret = min_t(size_t, txmsg->reply.u.remote_dpcd_read_ack.num_bytes,
+ size);
+ memcpy(bytes, txmsg->reply.u.remote_dpcd_read_ack.bytes, ret);
+
+fail_free:
+ kfree(txmsg);
+fail_put:
+ drm_dp_mst_topology_put_mstb(mstb);
+
+ return ret;
}
-#endif
static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr,
struct drm_dp_mst_port *port,
ret = drm_dp_mst_wait_tx_reply(mstb, txmsg);
if (ret > 0) {
if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK)
- ret = -EINVAL;
+ ret = -EIO;
else
ret = 0;
}
projects / linux.git / blobdiff