From: Douglas Anderson <dianders@xxxxxxxxxxxx>
[ Upstream commit 5e7222a3674ea7422370779884dd53aabe9e4a9d ]
If the HPD signal never asserts in panel_simple_prepare() and we
return an error, we should unset the enable GPIO and disable the
regulator to make it consistent for the caller.
At the moment I have some hardware where HPD sometimes doesn't assert.
Obviously that needs to be debugged, but this patch makes it so that
if I add a retry that I can make things work.
Fixes: 48834e6084f1 ("drm/panel-simple: Support hpd-gpios for delaying prepare()")
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115144345.v2.1.I33fcbd64ab409cfe4f9491bf449f51925a4d3281@changeid
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/panel/panel-simple.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 4e2dad314c79..e8b1a0e873ea 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -406,7 +406,7 @@ static int panel_simple_prepare(struct drm_panel *panel)
if (IS_ERR(p->hpd_gpio)) {
err = panel_simple_get_hpd_gpio(panel->dev, p, false);
if (err)
- return err;
+ goto error;
}
err = readx_poll_timeout(gpiod_get_value_cansleep, p->hpd_gpio,
@@ -418,13 +418,20 @@ static int panel_simple_prepare(struct drm_panel *panel)
if (err) {
dev_err(panel->dev,
"error waiting for hpd GPIO: %d\n", err);
- return err;
+ goto error;
}
}
p->prepared_time = ktime_get();
return 0;
+
+error:
+ gpiod_set_value_cansleep(p->enable_gpio, 0);
+ regulator_disable(p->supply);
+ p->unprepared_time = ktime_get();
+
+ return err;
}
static int panel_simple_enable(struct drm_panel *panel)
--
2.30.2
