linux-kernel - [PATCH v2 1/3] media: rcar-vin: Fold interrupt helpers into only callers

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Message-ID: <20250616185722.980722-2-niklas.soderlund+renesas@ragnatech.se>
Date: Mon, 16 Jun 2025 20:57:20 +0200
From: Niklas Söderlund <niklas.soderlund+renesas@...natech.se>
To: Mauro Carvalho Chehab <mchehab@...nel.org>,
	Geert Uytterhoeven <geert+renesas@...der.be>,
	Sakari Ailus <sakari.ailus@...ux.intel.com>,
	Laurent Pinchart <laurent.pinchart@...asonboard.com>,
	linux-media@...r.kernel.org,
	linux-renesas-soc@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: Niklas Söderlund <niklas.soderlund+renesas@...natech.se>,
	Laurent Pinchart <laurent.pinchart+renesas@...asonboard.com>
Subject: [PATCH v2 1/3] media: rcar-vin: Fold interrupt helpers into only callers

The call sites using the interrupt helper functions have all been
reworked to only one for each. Fold each of them into the only call
sites left.

This fixes a possible interrupt loss in case an interrupt occurs between
reading VNINTS_REG in rvin_get_interrupt_status() and reading it again
in rvin_ack_interrupt().

While at it rename the variable holding the current interrupt status to
make the code easier to read.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@...natech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@...asonboard.com>
---
* Changes since v1
- Extend commit message per Laurent's suggestion to indicate the
  possible fix of interrupt loss.
- Fix spelling of each.
---
 .../platform/renesas/rcar-vin/rcar-dma.c      | 27 +++++--------------
 1 file changed, 6 insertions(+), 21 deletions(-)

diff --git a/drivers/media/platform/renesas/rcar-vin/rcar-dma.c b/drivers/media/platform/renesas/rcar-vin/rcar-dma.c
index d4faa5a4e757..e1dae46b06d4 100644
--- a/drivers/media/platform/renesas/rcar-vin/rcar-dma.c
+++ b/drivers/media/platform/renesas/rcar-vin/rcar-dma.c
@@ -903,21 +903,6 @@ static int rvin_setup(struct rvin_dev *vin)
 	return 0;
 }
 
-static void rvin_disable_interrupts(struct rvin_dev *vin)
-{
-	rvin_write(vin, 0, VNIE_REG);
-}
-
-static u32 rvin_get_interrupt_status(struct rvin_dev *vin)
-{
-	return rvin_read(vin, VNINTS_REG);
-}
-
-static void rvin_ack_interrupt(struct rvin_dev *vin)
-{
-	rvin_write(vin, rvin_read(vin, VNINTS_REG), VNINTS_REG);
-}
-
 static bool rvin_capture_active(struct rvin_dev *vin)
 {
 	return rvin_read(vin, VNMS_REG) & VNMS_CA;
@@ -1040,22 +1025,22 @@ static void rvin_capture_stop(struct rvin_dev *vin)
 static irqreturn_t rvin_irq(int irq, void *data)
 {
 	struct rvin_dev *vin = data;
-	u32 int_status, vnms;
+	u32 status, vnms;
 	int slot;
 	unsigned int handled = 0;
 	unsigned long flags;
 
 	spin_lock_irqsave(&vin->qlock, flags);
 
-	int_status = rvin_get_interrupt_status(vin);
-	if (!int_status)
+	status = rvin_read(vin, VNINTS_REG);
+	if (!status)
 		goto done;
 
-	rvin_ack_interrupt(vin);
+	rvin_write(vin, status, VNINTS_REG);
 	handled = 1;
 
 	/* Nothing to do if nothing was captured. */
-	if (!(int_status & VNINTS_FIS))
+	if (!(status & VNINTS_FIS))
 		goto done;
 
 	/* Nothing to do if not running. */
@@ -1400,7 +1385,7 @@ void rvin_stop_streaming(struct rvin_dev *vin)
 	rvin_set_stream(vin, 0);
 
 	/* disable interrupts */
-	rvin_disable_interrupts(vin);
+	rvin_write(vin, 0, VNIE_REG);
 
 	/* Return unprocessed buffers from hardware. */
 	for (unsigned int i = 0; i < HW_BUFFER_NUM; i++) {
-- 
2.49.0