ast_dp_is_connected() used to also check for link training success to report the DP connector as connected. Without this check, the physical_status is always connected. So if no monitor is present, it will fail to read the EDID and set the default resolution to 640x480 instead of 1024x768.
Signed-off-by: Jocelyn Falempe jfalempe@redhat.com Fixes: 2281475168d2 ("drm/ast: astdp: Perform link training during atomic_enable") Cc: Thomas Zimmermann tzimmermann@suse.de Cc: Dave Airlie airlied@redhat.com Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v6.12+ --- drivers/gpu/drm/ast/ast_dp.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/ast/ast_dp.c b/drivers/gpu/drm/ast/ast_dp.c index 0e282b7b167c..30aad5c0112a 100644 --- a/drivers/gpu/drm/ast/ast_dp.c +++ b/drivers/gpu/drm/ast/ast_dp.c @@ -17,6 +17,12 @@ static bool ast_astdp_is_connected(struct ast_device *ast) { if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF, AST_IO_VGACRDF_HPD)) return false; + /* + * HPD might be set even if no monitor is connected, so also check that + * the link training was successful. + */ + if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, AST_IO_VGACRDC_LINK_SUCCESS)) + return false; return true; }
base-commit: 798047e63ac970f105c49c22e6d44df901c486b2