[PATCH v2 16/18] media: rzg2l-cru: Add function pointer to check if FIFO is empty

[Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>]

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

Add a `fifo_empty` function pointer to the `rzg2l_cru_info` structure and
pass it as part of the OF data. On RZ/G3E and RZ/V2H(P) SoCs, checking if
the FIFO is empty requires a different register configuration.

Implement `rzg2l_fifo_empty()` and update the code to use it from the
function pointer.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@xxxxxxxxxxxxxx>
---
 .../platform/renesas/rzg2l-cru/rzg2l-core.c   |  1 +
 .../platform/renesas/rzg2l-cru/rzg2l-cru.h    |  3 +++
 .../platform/renesas/rzg2l-cru/rzg2l-video.c  | 23 +++++++++++++------
 3 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c
index 302f792cb415..e4fb3e12d6bf 100644
--- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c
+++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-core.c
@@ -362,6 +362,7 @@ static const struct rzg2l_cru_info rzgl2_cru_info = {
 	.irq_handler = rzg2l_cru_irq,
 	.enable_interrupts = rzg2l_cru_enable_interrupts,
 	.disable_interrupts = rzg2l_cru_disable_interrupts,
+	.fifo_empty = rzg2l_fifo_empty,
 };
 
 static const struct of_device_id rzg2l_cru_of_id_table[] = {
diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
index 3f694044d8cd..2e17bfef43ce 100644
--- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
+++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
@@ -88,6 +88,7 @@ struct rzg2l_cru_info {
 	irqreturn_t (*irq_handler)(int irq, void *data);
 	void (*enable_interrupts)(struct rzg2l_cru_dev *cru);
 	void (*disable_interrupts)(struct rzg2l_cru_dev *cru);
+	bool (*fifo_empty)(struct rzg2l_cru_dev *cru);
 };
 
 /**
@@ -185,4 +186,6 @@ const struct rzg2l_cru_ip_format *rzg2l_cru_ip_index_to_fmt(u32 index);
 void rzg2l_cru_enable_interrupts(struct rzg2l_cru_dev *cru);
 void rzg2l_cru_disable_interrupts(struct rzg2l_cru_dev *cru);
 
+bool rzg2l_fifo_empty(struct rzg2l_cru_dev *cru);
+
 #endif
diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
index 5ffa3173af62..7cc83486ce03 100644
--- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
+++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
@@ -244,9 +244,23 @@ static int rzg2l_cru_initialize_image_conv(struct rzg2l_cru_dev *cru,
 	return 0;
 }
 
-void rzg2l_cru_stop_image_processing(struct rzg2l_cru_dev *cru)
+bool rzg2l_fifo_empty(struct rzg2l_cru_dev *cru)
 {
 	u32 amnfifopntr, amnfifopntr_w, amnfifopntr_r_y;
+
+	amnfifopntr = rzg2l_cru_read(cru, AMnFIFOPNTR);
+
+	amnfifopntr_w = amnfifopntr & AMnFIFOPNTR_FIFOWPNTR;
+	amnfifopntr_r_y =
+		(amnfifopntr & AMnFIFOPNTR_FIFORPNTR_Y) >> 16;
+	if (amnfifopntr_w == amnfifopntr_r_y)
+		return true;
+
+	return false;
+}
+
+void rzg2l_cru_stop_image_processing(struct rzg2l_cru_dev *cru)
+{
 	unsigned int retries = 0;
 	unsigned long flags;
 	u32 icnms;
@@ -274,12 +288,7 @@ void rzg2l_cru_stop_image_processing(struct rzg2l_cru_dev *cru)
 
 	/* Wait until the FIFO becomes empty */
 	for (retries = 5; retries > 0; retries--) {
-		amnfifopntr = rzg2l_cru_read(cru, AMnFIFOPNTR);
-
-		amnfifopntr_w = amnfifopntr & AMnFIFOPNTR_FIFOWPNTR;
-		amnfifopntr_r_y =
-			(amnfifopntr & AMnFIFOPNTR_FIFORPNTR_Y) >> 16;
-		if (amnfifopntr_w == amnfifopntr_r_y)
+		if (cru->info->fifo_empty(cru))
 			break;
 
 		usleep_range(10, 20);
-- 
2.34.1