Commit f89001ea authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/ast: astdp: Move locking into EDID helper 



The modeset mutex protects EDID retrival from concurrent modeset
operations. Acquire the lock in ast_astdp_read_edid(). Prepares the
code for conversion to struct drm_edid.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarJocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240815151953.184679-4-tzimmermann@suse.de
parent 80431c01

drivers/gpu/drm/ast/ast_dp.c

+10 −14
Original line number Diff line number Diff line
@@ -26,6 +26,12 @@ static int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata) 
	int ret = 0;

	u8 i;



	/*

	 * Protect access to I/O registers from concurrent modesetting

	 * by acquiring the I/O-register lock.

	 */

	mutex_lock(&ast->modeset_lock);



	/* Start reading EDID data */

	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xe5, (u8)~AST_IO_VGACRE5_EDID_READ_DONE, 0x00);
@@ -95,6 +101,8 @@ static int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata) 
	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xe5, (u8)~AST_IO_VGACRE5_EDID_READ_DONE,

			       AST_IO_VGACRE5_EDID_READ_DONE);



	mutex_unlock(&ast->modeset_lock);



	return ret;

}
@@ -324,9 +332,6 @@ static const struct drm_encoder_helper_funcs ast_astdp_encoder_helper_funcs = { 
static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector)

{

	void *edid;

	struct drm_device *dev = connector->dev;

	struct ast_device *ast = to_ast_device(dev);



	int succ;

	int count;
@@ -334,17 +339,9 @@ static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector) 
	if (!edid)

		goto err_drm_connector_update_edid_property;



	/*

	 * Protect access to I/O registers from concurrent modesetting

	 * by acquiring the I/O-register lock.

	 */

	mutex_lock(&ast->modeset_lock);



	succ = ast_astdp_read_edid(connector->dev, edid);

	if (succ < 0)

		goto err_mutex_unlock;



	mutex_unlock(&ast->modeset_lock);

		goto err_kfree;



	drm_connector_update_edid_property(connector, edid);

	count = drm_add_edid_modes(connector, edid);
@@ -352,8 +349,7 @@ static int ast_astdp_connector_helper_get_modes(struct drm_connector *connector) 


	return count;



err_mutex_unlock:

	mutex_unlock(&ast->modeset_lock);

err_kfree:

	kfree(edid);

err_drm_connector_update_edid_property:

	drm_connector_update_edid_property(connector, NULL);