[PATCH v2 08/10] drm/bridge: analogix_dp: Skip native HPD interrupt ops for GPIO HPD

[Damon Ding]

GPIO HPD does not rely on DP controller internal native HPD interrupts.
Skip native HPD register manipulations to avoid irrelevant operations.

In analogix_dp_config_interrupt(), mute all native HPD interrupts when
dp->hpd_gpiod is set. Move the dp->hpd_gpiod guard from inside
analogix_dp_clear_hotplug_interrupts() to its caller in the threaded
IRQ handler, so that the function operates purely on the given irq_type
bitmask without implicit mode-dependent behavior. This makes it
reusable for future callers that may need to clear specific interrupt
status bits regardless of the HPD detection mode.

Signed-off-by: Damon Ding <damon.ding at rock-chips.com>

---

Changes in v2:
- Adapt to the newly added IRQF_ONESHOT related commit and expand the
  commit msg.
---
 .../drm/bridge/analogix/analogix_dp_core.c    |  2 +-
 .../gpu/drm/bridge/analogix/analogix_dp_reg.c | 30 +++++++++++--------
 2 files changed, 18 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index d207cc864bdc..f05db455b430 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -720,7 +720,7 @@ static irqreturn_t analogix_dp_irq_thread(int irq, void *arg)
 	bool hpd_detected;
 
 	irq_type = analogix_dp_get_irq_type(dp);
-	if (irq_type)
+	if (!dp->hpd_gpiod && irq_type)
 		analogix_dp_clear_hotplug_interrupts(dp, irq_type);
 
 	if (!dp->hpd_gpiod && analogix_dp_is_rockchip(dp->plat_data->dev_type))
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
index fa8e2f104d6c..4b210e685747 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
@@ -182,18 +182,22 @@ void analogix_dp_config_interrupt(struct analogix_dp_device *dp)
 	writel(0, dp->reg_base + ANALOGIX_DP_COMMON_INT_MASK_2);
 	writel(0, dp->reg_base + ANALOGIX_DP_COMMON_INT_MASK_3);
 
-	/*
-	 * Either HOTPLUG_CHG interrupt or PLUG + HPD_LOST interrupt
-	 * pair can be used to implement hotplug detection.
-	 *
-	 * On Rockchip platforms, configuring HPD deglitch to 2ms and
-	 * using HOTPLUG_CHG interrupt for hotplug detection is proven
-	 * as a better solution via engineering verification.
-	 */
-	if (analogix_dp_is_rockchip(dp->plat_data->dev_type))
-		analogix_dp_unmute_hpd_interrupt(dp, DP_IRQ_TYPE_HP_CHANGE);
-	else
-		analogix_dp_unmute_hpd_interrupt(dp, HPD_IRQ);
+	if (dp->hpd_gpiod) {
+		analogix_dp_mute_hpd_interrupt(dp, HPD_IRQ);
+	} else {
+		/*
+		 * Either HOTPLUG_CHG interrupt or PLUG + HPD_LOST interrupt
+		 * pair can be used to implement hotplug detection.
+		 *
+		 * On Rockchip platforms, configuring HPD deglitch to 2ms and
+		 * using HOTPLUG_CHG interrupt for hotplug detection is proven
+		 * as a better solution via engineering verification.
+		 */
+		if (analogix_dp_is_rockchip(dp->plat_data->dev_type))
+			analogix_dp_unmute_hpd_interrupt(dp, DP_IRQ_TYPE_HP_CHANGE);
+		else
+			analogix_dp_unmute_hpd_interrupt(dp, HPD_IRQ);
+	}
 }
 
 void analogix_dp_mute_hpd_interrupt(struct analogix_dp_device *dp, u32 irq_type)
@@ -413,7 +417,7 @@ void analogix_dp_clear_hotplug_interrupts(struct analogix_dp_device *dp, u32 irq
 {
 	u32 reg = 0;
 
-	if (dp->hpd_gpiod || !irq_type)
+	if (!irq_type)
 		return;
 
 	if (irq_type & COMMON_INT_4_HPD_IRQ) {
-- 
2.34.1