Commit 6f77b2ac authored by Eryk Brol's avatar Eryk Brol Committed by Alex Deucher
Browse files

drm/amd/display: Add connector HPD trigger debugfs entry 



[why]
Need a tool to retrigger a virtual hotplug for testing purposes with
force redetection in both DC and DM.

[how]
Emulate handle_hpd_irq for connector as if usermode would trigger
a hotplug. Perform DC link discovery, DM connector update, and
DM force atomic commit.

In order to trigger HPD on the connector user needs to echo 1 into
"trigger_hotplug" debugfs entry on its respective connector.

Signed-off-by: default avatarEryk Brol <eryk.brol@amd.com>
Signed-off-by: default avatarMikita Lipski <mikita.lipski@amd.com>
Reviewed-by: default avatarMikita Lipski <Mikita.Lipski@amd.com>
Acked-by: default avatarEryk Brol <eryk.brol@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 237070fd

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c

+81 −0
Original line number Diff line number Diff line
@@ -1049,6 +1049,81 @@ static int dp_dsc_fec_support_show(struct seq_file *m, void *data) 
	return ret;

}



/* function: Trigger virtual HPD redetection on connector

 *

 * This function will perform link rediscovery, link disable

 * and enable, and dm connector state update.

 *

 * Retrigger HPD on an existing connector by echoing 1 into

 * its respectful "trigger_hotplug" debugfs entry:

 *

 *	echo 1 > /sys/kernel/debug/dri/0/DP-X/trigger_hotplug

 *

 */

static ssize_t dp_trigger_hotplug(struct file *f, const char __user *buf,

							size_t size, loff_t *pos)

{

	struct amdgpu_dm_connector *aconnector = file_inode(f)->i_private;

	struct drm_connector *connector = &aconnector->base;

	struct drm_device *dev = connector->dev;

	enum dc_connection_type new_connection_type = dc_connection_none;

	char *wr_buf = NULL;

	uint32_t wr_buf_size = 42;

	int max_param_num = 1;

	long param[1] = {0};

	uint8_t param_nums = 0;



	if (!aconnector || !aconnector->dc_link)

		return -EINVAL;



	if (size == 0)

		return -EINVAL;



	wr_buf = kcalloc(wr_buf_size, sizeof(char), GFP_KERNEL);



	if (!wr_buf) {

		DRM_DEBUG_DRIVER("no memory to allocate write buffer\n");

		return -ENOSPC;

	}



	if (parse_write_buffer_into_params(wr_buf, wr_buf_size,

						(long *)param, buf,

						max_param_num,

						&param_nums))

		return -EINVAL;



	if (param_nums <= 0) {

		DRM_DEBUG_DRIVER("user data not be read\n");

		kfree(wr_buf);

		return -EINVAL;

	}



	if (param[0] == 1) {

		mutex_lock(&aconnector->hpd_lock);



		if (!dc_link_detect_sink(aconnector->dc_link, &new_connection_type) &&

			new_connection_type != dc_connection_none)

			goto unlock;



		if (!dc_link_detect(aconnector->dc_link, DETECT_REASON_HPD))

			goto unlock;



		amdgpu_dm_update_connector_after_detect(aconnector);



		drm_modeset_lock_all(dev);

		dm_restore_drm_connector_state(dev, connector);

		drm_modeset_unlock_all(dev);



		drm_kms_helper_hotplug_event(dev);



unlock:

		mutex_unlock(&aconnector->hpd_lock);

	}



	kfree(wr_buf);

	return size;

}



/* function: read DSC status on the connector

 *

 * The read function: dp_dsc_clock_en_read
@@ -1967,6 +2042,12 @@ static const struct file_operations dp_dsc_slice_bpg_offset_debugfs_fops = { 
	.llseek = default_llseek

};



static const struct file_operations dp_trigger_hotplug_debugfs_fops = {

	.owner = THIS_MODULE,

	.write = dp_trigger_hotplug,

	.llseek = default_llseek

};



static const struct file_operations dp_link_settings_debugfs_fops = {

	.owner = THIS_MODULE,

	.read = dp_link_settings_read,