[PATCH v3] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers

[PATCH v3] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers

[Chintan Patel]

Convert the driver to use the non-deprecated mipi_dsi_*_multi() helpers and
mipi_dsi_msleep().

Switch DCS command sequences to the multi context API and
accumulate errors via struct mipi_dsi_multi_context. Replace
open-coded error handling with the multi helpers and convert
nt36672a_send_cmds() and power sequencing accordingly.

This patch is intended to functionally be a no-op, though there is one
slight change. Previously a failure in regulator_bulk_disable() would
have caused nt36672a_panel_unprepare() to return an error. Now it
won't. No other errors in nt36672a_panel_unprepare() were propagated,
so this makes things consistent.

Signed-off-by: Chintan Patel <chintanlike@gmail.com>
---
Changes in v3:
- Keep local ret variable in nt36672a_panel_power_off() to preserve error code in logging.
- Change mipi_dsi_msleep() back to regular msleep(60) in power-down sequence to preserve behavior.
- Reset dsi_ctx.accum_err before set_display_off_multi() and before power-down to preserve original error-tolerant shutdown behavior.

Changes in v2:
- Address alignment feedback from Doug.
- Restore original power-down ordering.
- Drop return value from nt36672a_panel_power_off().
- Consolidate error handling around dsi_ctx.accum_err.

 .../gpu/drm/panel/panel-novatek-nt36672a.c    | 94 ++++++-------------
 1 file changed, 30 insertions(+), 64 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-novatek-nt36672a.c b/drivers/gpu/drm/panel/panel-novatek-nt36672a.c
index 29e1f6aea480..7e8b5e059575 100644
--- a/drivers/gpu/drm/panel/panel-novatek-nt36672a.c
+++ b/drivers/gpu/drm/panel/panel-novatek-nt36672a.c
@@ -79,70 +79,57 @@ static inline struct nt36672a_panel *to_nt36672a_panel(struct drm_panel *panel)
 	return container_of(panel, struct nt36672a_panel, base);
 }
 
-static int nt36672a_send_cmds(struct drm_panel *panel, const struct nt36672a_panel_cmd *cmds,
-			      int num)
+static void nt36672a_send_cmds(struct mipi_dsi_multi_context *dsi_ctx,
+			       const struct nt36672a_panel_cmd *cmds, int num)
 {
-	struct nt36672a_panel *pinfo = to_nt36672a_panel(panel);
 	unsigned int i;
-	int err;
 
 	for (i = 0; i < num; i++) {
 		const struct nt36672a_panel_cmd *cmd = &cmds[i];
 
-		err = mipi_dsi_dcs_write(pinfo->link, cmd->data[0], cmd->data + 1, 1);
-
-		if (err < 0)
-			return err;
+		/* cmd->data[0] is the DCS command, cmd->data[1] is the parameter */
+		mipi_dsi_dcs_write_buffer_multi(dsi_ctx, cmd->data, sizeof(cmd->data));
 	}
-
-	return 0;
 }
 
-static int nt36672a_panel_power_off(struct drm_panel *panel)
+static void nt36672a_panel_power_off(struct drm_panel *panel)
 {
 	struct nt36672a_panel *pinfo = to_nt36672a_panel(panel);
-	int ret = 0;
+	int ret;
 
 	gpiod_set_value(pinfo->reset_gpio, 1);
 
 	ret = regulator_bulk_disable(ARRAY_SIZE(pinfo->supplies), pinfo->supplies);
 	if (ret)
 		dev_err(panel->dev, "regulator_bulk_disable failed %d\n", ret);
-
-	return ret;
 }
 
 static int nt36672a_panel_unprepare(struct drm_panel *panel)
 {
 	struct nt36672a_panel *pinfo = to_nt36672a_panel(panel);
-	int ret;
+	struct mipi_dsi_multi_context dsi_ctx = { .dsi = pinfo->link };
 
 	/* send off cmds */
-	ret = nt36672a_send_cmds(panel, pinfo->desc->off_cmds,
-				 pinfo->desc->num_off_cmds);
+	nt36672a_send_cmds(&dsi_ctx, pinfo->desc->off_cmds,
+			   pinfo->desc->num_off_cmds);
 
-	if (ret < 0)
-		dev_err(panel->dev, "failed to send DCS off cmds: %d\n", ret);
-
-	ret = mipi_dsi_dcs_set_display_off(pinfo->link);
-	if (ret < 0)
-		dev_err(panel->dev, "set_display_off cmd failed ret = %d\n", ret);
+	/* Reset error to continue with display off even if send_cmds failed */
+	dsi_ctx.accum_err = 0;
+	mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
+	/* Reset error to continue power-down even if display off failed */
+	dsi_ctx.accum_err = 0;
 
 	/* 120ms delay required here as per DCS spec */
 	msleep(120);
 
-	ret = mipi_dsi_dcs_enter_sleep_mode(pinfo->link);
-	if (ret < 0)
-		dev_err(panel->dev, "enter_sleep cmd failed ret = %d\n", ret);
+	mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
 
 	/* 0x3C = 60ms delay */
 	msleep(60);
 
-	ret = nt36672a_panel_power_off(panel);
-	if (ret < 0)
-		dev_err(panel->dev, "power_off failed ret = %d\n", ret);
+	nt36672a_panel_power_off(panel);
 
-	return ret;
+	return 0;
 }
 
 static int nt36672a_panel_power_on(struct nt36672a_panel *pinfo)
@@ -170,52 +157,31 @@ static int nt36672a_panel_power_on(struct nt36672a_panel *pinfo)
 static int nt36672a_panel_prepare(struct drm_panel *panel)
 {
 	struct nt36672a_panel *pinfo = to_nt36672a_panel(panel);
-	int err;
+	struct mipi_dsi_multi_context dsi_ctx = { .dsi = pinfo->link };
 
-	err = nt36672a_panel_power_on(pinfo);
-	if (err < 0)
-		goto poweroff;
+	dsi_ctx.accum_err = nt36672a_panel_power_on(pinfo);
 
 	/* send first part of init cmds */
-	err = nt36672a_send_cmds(panel, pinfo->desc->on_cmds_1,
-				 pinfo->desc->num_on_cmds_1);
+	nt36672a_send_cmds(&dsi_ctx, pinfo->desc->on_cmds_1,
+			   pinfo->desc->num_on_cmds_1);
 
-	if (err < 0) {
-		dev_err(panel->dev, "failed to send DCS Init 1st Code: %d\n", err);
-		goto poweroff;
-	}
-
-	err = mipi_dsi_dcs_exit_sleep_mode(pinfo->link);
-	if (err < 0) {
-		dev_err(panel->dev, "failed to exit sleep mode: %d\n", err);
-		goto poweroff;
-	}
+	mipi_dsi_dcs_exit_sleep_mode_multi(&dsi_ctx);
 
 	/* 0x46 = 70 ms delay */
-	msleep(70);
+	mipi_dsi_msleep(&dsi_ctx, 70);
 
-	err = mipi_dsi_dcs_set_display_on(pinfo->link);
-	if (err < 0) {
-		dev_err(panel->dev, "failed to Set Display ON: %d\n", err);
-		goto poweroff;
-	}
+	mipi_dsi_dcs_set_display_on_multi(&dsi_ctx);
 
 	/* Send rest of the init cmds */
-	err = nt36672a_send_cmds(panel, pinfo->desc->on_cmds_2,
-				 pinfo->desc->num_on_cmds_2);
+	nt36672a_send_cmds(&dsi_ctx, pinfo->desc->on_cmds_2,
+			   pinfo->desc->num_on_cmds_2);
 
-	if (err < 0) {
-		dev_err(panel->dev, "failed to send DCS Init 2nd Code: %d\n", err);
-		goto poweroff;
-	}
+	mipi_dsi_msleep(&dsi_ctx, 120);
 
-	msleep(120);
+	if (dsi_ctx.accum_err < 0)
+		gpiod_set_value(pinfo->reset_gpio, 0);
 
-	return 0;
-
-poweroff:
-	gpiod_set_value(pinfo->reset_gpio, 0);
-	return err;
+	return dsi_ctx.accum_err;
 }
 
 static int nt36672a_panel_get_modes(struct drm_panel *panel,
-- 
2.43.0

Re: [PATCH v3] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers

[Doug Anderson]

Hi,

On Wed, Mar 4, 2026 at 8:49 PM Chintan Patel <chintanlike@gmail.com> wrote:
>
> Convert the driver to use the non-deprecated mipi_dsi_*_multi() helpers and
> mipi_dsi_msleep().
>
> Switch DCS command sequences to the multi context API and
> accumulate errors via struct mipi_dsi_multi_context. Replace
> open-coded error handling with the multi helpers and convert
> nt36672a_send_cmds() and power sequencing accordingly.
>
> This patch is intended to functionally be a no-op, though there is one
> slight change. Previously a failure in regulator_bulk_disable() would
> have caused nt36672a_panel_unprepare() to return an error. Now it
> won't. No other errors in nt36672a_panel_unprepare() were propagated,
> so this makes things consistent.
>
> Signed-off-by: Chintan Patel <chintanlike@gmail.com>
> ---
> Changes in v3:
> - Keep local ret variable in nt36672a_panel_power_off() to preserve error code in logging.
> - Change mipi_dsi_msleep() back to regular msleep(60) in power-down sequence to preserve behavior.
> - Reset dsi_ctx.accum_err before set_display_off_multi() and before power-down to preserve original error-tolerant shutdown behavior.
>
> Changes in v2:
> - Address alignment feedback from Doug.
> - Restore original power-down ordering.
> - Drop return value from nt36672a_panel_power_off().
> - Consolidate error handling around dsi_ctx.accum_err.
>
>  .../gpu/drm/panel/panel-novatek-nt36672a.c    | 94 ++++++-------------
>  1 file changed, 30 insertions(+), 64 deletions(-)

Looks good to me now. I'll plan to apply in ~1 week if there is no
further feedback.

Reviewed-by: Douglas Anderson <dianders@chromium.org>

As per my response in v1 [1], someone could still do additional
cleanup to move away from the table-based initialization, but it
doesn't make sense to block this patch on that. :-)

[1] https://lore.kernel.org/r/CAD=FV=WtjW5WWmjeb2zwF2PjiJeZv1jZS_UKZ0bT1658=CkwVA@mail.gmail.com

-Doug

Re: [PATCH v3] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers

[Chintan Patel]

On 3/6/26 09:40, Doug Anderson wrote:
> Hi,
> 
> On Wed, Mar 4, 2026 at 8:49 PM Chintan Patel <chintanlike@gmail.com> wrote:
>>
>> Convert the driver to use the non-deprecated mipi_dsi_*_multi() helpers and
>> mipi_dsi_msleep().
>>
>> Switch DCS command sequences to the multi context API and
>> accumulate errors via struct mipi_dsi_multi_context. Replace
>> open-coded error handling with the multi helpers and convert
>> nt36672a_send_cmds() and power sequencing accordingly.
>>
>> This patch is intended to functionally be a no-op, though there is one
>> slight change. Previously a failure in regulator_bulk_disable() would
>> have caused nt36672a_panel_unprepare() to return an error. Now it
>> won't. No other errors in nt36672a_panel_unprepare() were propagated,
>> so this makes things consistent.
>>
>> Signed-off-by: Chintan Patel <chintanlike@gmail.com>
>> ---
>> Changes in v3:
>> - Keep local ret variable in nt36672a_panel_power_off() to preserve error code in logging.
>> - Change mipi_dsi_msleep() back to regular msleep(60) in power-down sequence to preserve behavior.
>> - Reset dsi_ctx.accum_err before set_display_off_multi() and before power-down to preserve original error-tolerant shutdown behavior.
>>
>> Changes in v2:
>> - Address alignment feedback from Doug.
>> - Restore original power-down ordering.
>> - Drop return value from nt36672a_panel_power_off().
>> - Consolidate error handling around dsi_ctx.accum_err.
>>
>>   .../gpu/drm/panel/panel-novatek-nt36672a.c    | 94 ++++++-------------
>>   1 file changed, 30 insertions(+), 64 deletions(-)
> 
> Looks good to me now. I'll plan to apply in ~1 week if there is no
> further feedback.
> 
> Reviewed-by: Douglas Anderson <dianders@chromium.org>
> 
> As per my response in v1 [1], someone could still do additional
> cleanup to move away from the table-based initialization, but it
> doesn't make sense to block this patch on that. :-)
> 

Agree - I have plan to address as separate patch.

> [1] https://lore.kernel.org/r/CAD=FV=WtjW5WWmjeb2zwF2PjiJeZv1jZS_UKZ0bT1658=CkwVA@mail.gmail.com
> 
> -Doug

Re: [PATCH v3] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers

[Doug Anderson]

Hi,

On Wed, Mar 4, 2026 at 8:49 PM Chintan Patel <chintanlike@gmail.com> wrote:
>
> Convert the driver to use the non-deprecated mipi_dsi_*_multi() helpers and
> mipi_dsi_msleep().
>
> Switch DCS command sequences to the multi context API and
> accumulate errors via struct mipi_dsi_multi_context. Replace
> open-coded error handling with the multi helpers and convert
> nt36672a_send_cmds() and power sequencing accordingly.
>
> This patch is intended to functionally be a no-op, though there is one
> slight change. Previously a failure in regulator_bulk_disable() would
> have caused nt36672a_panel_unprepare() to return an error. Now it
> won't. No other errors in nt36672a_panel_unprepare() were propagated,
> so this makes things consistent.
>
> Signed-off-by: Chintan Patel <chintanlike@gmail.com>
> ---
> Changes in v3:
> - Keep local ret variable in nt36672a_panel_power_off() to preserve error code in logging.
> - Change mipi_dsi_msleep() back to regular msleep(60) in power-down sequence to preserve behavior.
> - Reset dsi_ctx.accum_err before set_display_off_multi() and before power-down to preserve original error-tolerant shutdown behavior.
>
> Changes in v2:
> - Address alignment feedback from Doug.
> - Restore original power-down ordering.
> - Drop return value from nt36672a_panel_power_off().
> - Consolidate error handling around dsi_ctx.accum_err.
>
>  .../gpu/drm/panel/panel-novatek-nt36672a.c    | 94 ++++++-------------
>  1 file changed, 30 insertions(+), 64 deletions(-)

Pushed to drm-misc-next:

[1/1] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers
      commit: bc4cb68a02f1a445aa65d8054bd69ba4ba3f5767

Re: [PATCH v3] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers

[Chintan Patel]

On 3/13/26 08:46, Doug Anderson wrote:
> Hi,
> 
> On Wed, Mar 4, 2026 at 8:49 PM Chintan Patel <chintanlike@gmail.com> wrote:
>>
>> Convert the driver to use the non-deprecated mipi_dsi_*_multi() helpers and
>> mipi_dsi_msleep().
>>
>> Switch DCS command sequences to the multi context API and
>> accumulate errors via struct mipi_dsi_multi_context. Replace
>> open-coded error handling with the multi helpers and convert
>> nt36672a_send_cmds() and power sequencing accordingly.
>>
>> This patch is intended to functionally be a no-op, though there is one
>> slight change. Previously a failure in regulator_bulk_disable() would
>> have caused nt36672a_panel_unprepare() to return an error. Now it
>> won't. No other errors in nt36672a_panel_unprepare() were propagated,
>> so this makes things consistent.
>>
>> Signed-off-by: Chintan Patel <chintanlike@gmail.com>
>> ---
>> Changes in v3:
>> - Keep local ret variable in nt36672a_panel_power_off() to preserve error code in logging.
>> - Change mipi_dsi_msleep() back to regular msleep(60) in power-down sequence to preserve behavior.
>> - Reset dsi_ctx.accum_err before set_display_off_multi() and before power-down to preserve original error-tolerant shutdown behavior.
>>
>> Changes in v2:
>> - Address alignment feedback from Doug.
>> - Restore original power-down ordering.
>> - Drop return value from nt36672a_panel_power_off().
>> - Consolidate error handling around dsi_ctx.accum_err.
>>
>>   .../gpu/drm/panel/panel-novatek-nt36672a.c    | 94 ++++++-------------
>>   1 file changed, 30 insertions(+), 64 deletions(-)
> 
> Pushed to drm-misc-next:
> 
> [1/1] drm/panel: novatek-nt36672a: Convert to mipi_dsi_*_multi() helpers
>        commit: bc4cb68a02f1a445aa65d8054bd69ba4ba3f5767

Thank you Doug!