On 29/09/2026 11:51, Krzysztof Kozlowski wrote:
On 29/09/2026 11:41, David Heidelberg wrote:
On 29/09/2026 09:45, Krzysztof Kozlowski wrote:
On Thu, Sep 24, 2026 at 04:01:34PM +0200, David Heidelberg wrote:
The reset was introduced with wrong polarity. Correct for the future
compatibles and keep current with reverted logic.
Old DTs keep GPIO_ACTIVE_HIGH and are fixed up via
gpiod_toggle_active_low() on the deprecated compatible.
Assisted-by: LLM
Reviewed-by: Neil Armstrong <[email protected]>
Signed-off-by: David Heidelberg <[email protected]>
---
drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
b/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
index 5e1e997b83b36..99290913de69a 100644
--- a/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
+++ b/drivers/gpu/drm/panel/panel-samsung-s6e3ha8.c
@@ -20,16 +20,17 @@
#include "panel-samsung-dsi.h"
struct s6e3ha8_desc {
const struct drm_panel_funcs *funcs;
const struct drm_display_mode *mode;
unsigned long mode_flags;
const struct regulator_bulk_data *supplies;
unsigned int num_supplies;
+ bool broken_reset_polarity;
};
struct s6e3ha8 {
struct drm_panel panel;
struct mipi_dsi_device *dsi;
const struct s6e3ha8_desc *desc;
struct drm_dsc_config dsc;
struct gpio_desc *reset_gpio;
@@ -62,22 +63,22 @@ static int s6e3ha8_unprepare(struct drm_panel *panel)
{
struct s6e3ha8 *priv = to_s6e3ha8(panel);
return regulator_bulk_disable(priv->desc->num_supplies, priv->supplies);
}
static void s6e3ha8_amb577px01_wqhd_reset(struct s6e3ha8 *priv)
{
- gpiod_set_value_cansleep(priv->reset_gpio, 1);
- usleep_range(5000, 6000);
gpiod_set_value_cansleep(priv->reset_gpio, 0);
usleep_range(5000, 6000);
gpiod_set_value_cansleep(priv->reset_gpio, 1);
usleep_range(5000, 6000);
+ gpiod_set_value_cansleep(priv->reset_gpio, 0);
This breaks all users and this usage of ABI was already released.
See the gpiod_toggle_active_low() usage later in the patch which keep the logic
for the original compatible as intended.
OK, I went way too fast, that's correct part. But splitting fix is still
just confusing. Backporting to stable is a different thing than fixing
issues.
Sure, I already droped the previous commit changing it for stable.
Btw. looking at gpiod_toggle_active_low(), would it make sense to do a series
correcting panel reset logic? I see many panels keep "reset asserted" in the
driver (but ofc not in the reality).
Thanks
David
Best regards,
Krzysztof
