Re: [PATCH 13/14] media: rzg2l-cru: Remove the 'state' variable

[Dan Scally <dan.scally@ideasonboard.com>]

Hi Jacopo

On 27/03/2026 17:10, Jacopo Mondi wrote:
> From: Jacopo Mondi <jacopo.mondi+renesas@ideasonboard.com>
> 
> The cru driver uses a 'state' variable for debugging purpose in the
> interrupt handler. The state is used to detect invalid usage conditions
> that are not meant to happen unless the driver has a bug in handling the
> stop and start conditions.
> 
> Remove the state variable which seems to be a debugging leftover.
> 
> Signed-off-by: Jacopo Mondi <jacopo.mondi+renesas@ideasonboard.com>
> ---

Just one comment near the bottom...

>   .../media/platform/renesas/rzg2l-cru/rzg2l-cru.h   | 15 -----
>   .../media/platform/renesas/rzg2l-cru/rzg2l-video.c | 74 +---------------------
>   2 files changed, 3 insertions(+), 86 deletions(-)
> 
> diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
> index bc66b0c8c15e..56359491739e 100644
> --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
> +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-cru.h
> @@ -36,20 +36,6 @@ enum rzg2l_csi2_pads {
>   
>   struct rzg2l_cru_dev;
>   
> -/**
> - * enum rzg2l_cru_dma_state - DMA states
> - * @RZG2L_CRU_DMA_STOPPED:   No operation in progress
> - * @RZG2L_CRU_DMA_STARTING:  Capture starting up
> - * @RZG2L_CRU_DMA_RUNNING:   Operation in progress have buffers
> - * @RZG2L_CRU_DMA_STOPPING:  Stopping operation
> - */
> -enum rzg2l_cru_dma_state {
> -	RZG2L_CRU_DMA_STOPPED = 0,
> -	RZG2L_CRU_DMA_STARTING,
> -	RZG2L_CRU_DMA_RUNNING,
> -	RZG2L_CRU_DMA_STOPPING,
> -};
> -
>   struct rzg2l_cru_csi {
>   	struct v4l2_async_connection *asd;
>   	struct v4l2_subdev *subdev;
> @@ -173,7 +159,6 @@ struct rzg2l_cru_dev {
>   	struct vb2_v4l2_buffer *queue_buf[RZG2L_CRU_HW_BUFFER_MAX];
>   	struct list_head buf_list;
>   	unsigned int sequence;
> -	enum rzg2l_cru_dma_state state;
>   
>   	struct v4l2_pix_format format;
>   };
> diff --git a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> index 45b58e2183bf..30424e2b6cc0 100644
> --- a/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> +++ b/drivers/media/platform/renesas/rzg2l-cru/rzg2l-video.c
> @@ -399,8 +399,6 @@ void rzg2l_cru_stop_image_processing(struct rzg2l_cru_dev *cru)
>   	if (icnms)
>   		dev_err(cru->dev, "Failed stop HW, something is seriously broken\n");
>   
> -	cru->state = RZG2L_CRU_DMA_STOPPED;
> -
>   	/* Wait until the FIFO becomes empty */
>   	for (retries = 5; retries > 0; retries--) {
>   		if (cru->info->fifo_empty(cru))
> @@ -588,8 +586,6 @@ static int rzg2l_cru_set_stream(struct rzg2l_cru_dev *cru, int on)
>   
>   static void rzg2l_cru_stop_streaming(struct rzg2l_cru_dev *cru)
>   {
> -	cru->state = RZG2L_CRU_DMA_STOPPING;
> -
>   	rzg2l_cru_set_stream(cru, 0);
>   }
>   
> @@ -601,8 +597,6 @@ irqreturn_t rzg2l_cru_irq(int irq, void *data)
>   	u32 amnmbs;
>   	int slot;
>   
> -	guard(spinlock_irqsave)(&cru->hw_lock);
> -
>   	irq_status = rzg2l_cru_read(cru, CRUnINTS);
>   	if (!irq_status)
>   		return IRQ_RETVAL(handled);
> @@ -611,20 +605,9 @@ irqreturn_t rzg2l_cru_irq(int irq, void *data)
>   
>   	rzg2l_cru_write(cru, CRUnINTS, rzg2l_cru_read(cru, CRUnINTS));
>   
> -	/* Nothing to do if capture status is 'RZG2L_CRU_DMA_STOPPED' */
> -	if (cru->state == RZG2L_CRU_DMA_STOPPED) {
> -		dev_dbg(cru->dev, "IRQ while state stopped\n");
> -		return IRQ_RETVAL(handled);
> -	}
> -
> -	/* Increase stop retries if capture status is 'RZG2L_CRU_DMA_STOPPING' */
> -	if (cru->state == RZG2L_CRU_DMA_STOPPING) {
> -		if (irq_status & CRUnINTS_SFS)
> -			dev_dbg(cru->dev, "IRQ while state stopping\n");
> -		return IRQ_RETVAL(handled);
> -	}
> +	/* Calculate slot and prepare for new capture. */
> +	guard(spinlock_irqsave)(&cru->hw_lock);
>   
> -	/* Prepare for capture and update state */
>   	amnmbs = rzg2l_cru_read(cru, AMnMBS);
>   	cru->active_slot = amnmbs & AMnMBS_MBSTS;
>   
> @@ -637,20 +620,6 @@ irqreturn_t rzg2l_cru_irq(int irq, void *data)
>   	else
>   		slot = cru->active_slot - 1;
>   
> -	/*
> -	 * To hand buffers back in a known order to userspace start
> -	 * to capture first from slot 0.
> -	 */
> -	if (cru->state == RZG2L_CRU_DMA_STARTING) {
> -		if (slot != 0) {
> -			dev_dbg(cru->dev, "Starting sync slot: %d\n", slot);
> -			return IRQ_RETVAL(handled);
> -		}
> -
> -		dev_dbg(cru->dev, "Capture start synced!\n");
> -		cru->state = RZG2L_CRU_DMA_RUNNING;
> -	}
> -
>   	/* Capture frame */
>   	if (cru->queue_buf[slot]) {
>   		cru->queue_buf[slot]->field = cru->format.field;
> @@ -678,49 +647,18 @@ irqreturn_t rzg3e_cru_irq(int irq, void *data)
>   	u32 irq_status;
>   	int slot;
>   
> -	guard(spinlock)(&cru->hw_lock);
> -
>   	irq_status = rzg2l_cru_read(cru, CRUnINTS2);
>   	if (!irq_status)
>   		return IRQ_NONE;
>   
> -	dev_dbg(cru->dev, "CRUnINTS2 0x%x\n", irq_status);
> -
>   	rzg2l_cru_write(cru, CRUnINTS2, rzg2l_cru_read(cru, CRUnINTS2));
>   
> -	/* Nothing to do if capture status is 'RZG2L_CRU_DMA_STOPPED' */
> -	if (cru->state == RZG2L_CRU_DMA_STOPPED) {
> -		dev_dbg(cru->dev, "IRQ while state stopped\n");
> -		return IRQ_HANDLED;
> -	}
> -
> -	if (cru->state == RZG2L_CRU_DMA_STOPPING) {
> -		if (irq_status & CRUnINTS2_FExS(0) ||
> -		    irq_status & CRUnINTS2_FExS(1) ||
> -		    irq_status & CRUnINTS2_FExS(2) ||
> -		    irq_status & CRUnINTS2_FExS(3))
> -			dev_dbg(cru->dev, "IRQ while state stopping\n");
> -		return IRQ_HANDLED;
> -	}
> -
> +	guard(spinlock)(&cru->hw_lock);
>   	slot = cru->active_slot;
>   	cru->active_slot = rzg2l_cru_slot_next(cru, cru->active_slot);
>   
>   	dev_dbg(cru->dev, "Current written slot: %d\n", slot);
>   
> -	/*
> -	 * To hand buffers back in a known order to userspace start
> -	 * to capture first from slot 0.
> -	 */
> -	if (cru->state == RZG2L_CRU_DMA_STARTING) {
> -		if (slot != 0) {
> -			dev_dbg(cru->dev, "Starting sync slot: %d\n", slot);
> -			return IRQ_HANDLED;
> -		}
> -		dev_dbg(cru->dev, "Capture start synced!\n");
> -		cru->state = RZG2L_CRU_DMA_RUNNING;
> -	}
> -
>   	/* Capture frame */
>   	if (cru->queue_buf[slot]) {
>   		struct vb2_v4l2_buffer *buf = cru->queue_buf[slot];
> @@ -730,9 +668,6 @@ irqreturn_t rzg3e_cru_irq(int irq, void *data)
>   		buf->vb2_buf.timestamp = ktime_get_ns();
>   		vb2_buffer_done(&buf->vb2_buf, VB2_BUF_STATE_DONE);
>   		cru->queue_buf[slot] = NULL;
> -	} else {
> -		/* Scratch buffer was used, dropping frame. */
> -		dev_dbg(cru->dev, "Dropping frame %u\n", cru->sequence);
>   	}

I guess this change was accidental? For the rest:

Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>

>   
>   	cru->sequence++;
> @@ -789,7 +724,6 @@ static int rzg2l_cru_start_streaming_vq(struct vb2_queue *vq, unsigned int count
>   		goto out;
>   	}
>   
> -	cru->state = RZG2L_CRU_DMA_STARTING;
>   	dev_dbg(cru->dev, "Starting to capture\n");
>   	return 0;
>   
> @@ -862,8 +796,6 @@ int rzg2l_cru_dma_register(struct rzg2l_cru_dev *cru)
>   	spin_lock_init(&cru->hw_lock);
>   	spin_lock_init(&cru->qlock);
>   
> -	cru->state = RZG2L_CRU_DMA_STOPPED;
> -
>   	for (i = 0; i < RZG2L_CRU_HW_BUFFER_MAX; i++)
>   		cru->queue_buf[i] = NULL;
>   
>