diff mbox series

[v2,06/10] media: ipu3-cio2: Use readl_poll_timeout() helper

Message ID 20200817160734.12402-6-andriy.shevchenko@linux.intel.com
State Accepted
Commit 44677b03caa3363da6f2810a83da367e55f026d9
Headers show
Series [v2,01/10] media: ipu3-cio2: Simplify cleanup code | expand

Commit Message

Andy Shevchenko Aug. 17, 2020, 4:07 p.m. UTC
We may use special helper macro to poll IO till condition or timeout occurs.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v2: wrapped long line (Bingbu)
 drivers/media/pci/intel/ipu3/ipu3-cio2.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

Comments

Laurent Pinchart Oct. 9, 2020, 1:14 a.m. UTC | #1
Hi Andy,

Thank you for the patch.

On Mon, Aug 17, 2020 at 07:07:29PM +0300, Andy Shevchenko wrote:
> We may use special helper macro to poll IO till condition or timeout occurs.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v2: wrapped long line (Bingbu)
>  drivers/media/pci/intel/ipu3/ipu3-cio2.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> index 36b4c7730f43..7bcde3ba8f6e 100644
> --- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> +++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
> @@ -14,6 +14,7 @@
>  
>  #include <linux/delay.h>
>  #include <linux/interrupt.h>
> +#include <linux/iopoll.h>
>  #include <linux/module.h>
>  #include <linux/pci.h>
>  #include <linux/pfn.h>
> @@ -507,8 +508,10 @@ static int cio2_hw_init(struct cio2_device *cio2, struct cio2_queue *q)
>  
>  static void cio2_hw_exit(struct cio2_device *cio2, struct cio2_queue *q)
>  {
> -	void __iomem *base = cio2->base;
> -	unsigned int i, maxloops = 1000;
> +	void __iomem *const base = cio2->base;
> +	unsigned int i;
> +	u32 value;
> +	int ret;
>  
>  	/* Disable CSI receiver and MIPI backend devices */
>  	writel(0, q->csi_rx_base + CIO2_REG_IRQCTRL_MASK);
> @@ -518,13 +521,10 @@ static void cio2_hw_exit(struct cio2_device *cio2, struct cio2_queue *q)
>  
>  	/* Halt DMA */
>  	writel(0, base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN));
> -	do {
> -		if (readl(base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN)) &
> -		    CIO2_CDMAC0_DMA_HALTED)
> -			break;
> -		usleep_range(1000, 2000);
> -	} while (--maxloops);
> -	if (!maxloops)
> +	ret = readl_poll_timeout(base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN),
> +				 value, value & CIO2_CDMAC0_DMA_HALTED,
> +				 4000, 2000000);

I had to read the implementation of readl_poll_timeout() to see why you
turned [1000, 2000] to 4000. This effectively becomes [1000, 4000] which
should be fine.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +	if (ret)
>  		dev_err(&cio2->pci_dev->dev,
>  			"DMA %i can not be halted\n", CIO2_DMA_CHAN);
>  
>
diff mbox series

Patch

diff --git a/drivers/media/pci/intel/ipu3/ipu3-cio2.c b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
index 36b4c7730f43..7bcde3ba8f6e 100644
--- a/drivers/media/pci/intel/ipu3/ipu3-cio2.c
+++ b/drivers/media/pci/intel/ipu3/ipu3-cio2.c
@@ -14,6 +14,7 @@ 
 
 #include <linux/delay.h>
 #include <linux/interrupt.h>
+#include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/pfn.h>
@@ -507,8 +508,10 @@  static int cio2_hw_init(struct cio2_device *cio2, struct cio2_queue *q)
 
 static void cio2_hw_exit(struct cio2_device *cio2, struct cio2_queue *q)
 {
-	void __iomem *base = cio2->base;
-	unsigned int i, maxloops = 1000;
+	void __iomem *const base = cio2->base;
+	unsigned int i;
+	u32 value;
+	int ret;
 
 	/* Disable CSI receiver and MIPI backend devices */
 	writel(0, q->csi_rx_base + CIO2_REG_IRQCTRL_MASK);
@@ -518,13 +521,10 @@  static void cio2_hw_exit(struct cio2_device *cio2, struct cio2_queue *q)
 
 	/* Halt DMA */
 	writel(0, base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN));
-	do {
-		if (readl(base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN)) &
-		    CIO2_CDMAC0_DMA_HALTED)
-			break;
-		usleep_range(1000, 2000);
-	} while (--maxloops);
-	if (!maxloops)
+	ret = readl_poll_timeout(base + CIO2_REG_CDMAC0(CIO2_DMA_CHAN),
+				 value, value & CIO2_CDMAC0_DMA_HALTED,
+				 4000, 2000000);
+	if (ret)
 		dev_err(&cio2->pci_dev->dev,
 			"DMA %i can not be halted\n", CIO2_DMA_CHAN);