6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jocelyn Falempe <jfale...@redhat.com>
commit c28f72c6ca98e039c2aa5aac6752c416bc31dbab upstream.
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 <jfale...@redhat.com>
Fixes: 2281475168d2 ("drm/ast: astdp: Perform link training during
atomic_enable")
Reported-by: Jerry Hoemann <jerry.hoem...@hpe.com>
Tested-by: Jose Lopez <jose.lo...@hpe.com>
Cc: Thomas Zimmermann <tzimmerm...@suse.de>
Cc: Dave Airlie <airl...@redhat.com>
Cc: dri-devel@lists.freedesktop.org
Cc: <sta...@vger.kernel.org> # v6.12+
Reviewed-by: Thomas Zimmermann <tzimmerm...@suse.de>
Link:
https://patchwork.freedesktop.org/patch/msgid/20250124141142.2434138-1-jfale...@redhat.com
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
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;
}
--
2.49.0
