[v3] Add Starfive Camera Subsystem driver

[PATCH v3 6/9] media: cadence: Add operation on reset

Posted by Jack Zhu 2 years, 10 months ago

Add operation on reset for Cadence MIPI-CSI2 RX Controller.

Signed-off-by: Jack Zhu <jack.zhu@starfivetech.com>
---
 drivers/media/platform/cadence/cdns-csi2rx.c | 30 ++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index cc3ebb0d96f6..a1555cedb349 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -13,6 +13,7 @@
 #include <linux/of_graph.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 
 #include <media/v4l2-ctrls.h>
@@ -68,6 +69,9 @@ struct csi2rx_priv {
 	struct clk			*sys_clk;
 	struct clk			*p_clk;
 	struct clk			*pixel_clk[CSI2RX_STREAMS_MAX];
+	struct reset_control		*sys_rst;
+	struct reset_control		*p_rst;
+	struct reset_control		*pixel_rst[CSI2RX_STREAMS_MAX];
 	struct phy			*dphy;
 
 	u8				lanes[CSI2RX_LANES_MAX];
@@ -112,6 +116,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
 	if (ret)
 		return ret;
 
+	reset_control_deassert(csi2rx->p_rst);
 	csi2rx_reset(csi2rx);
 
 	reg = csi2rx->num_lanes << 8;
@@ -154,6 +159,8 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
 		if (ret)
 			goto err_disable_pixclk;
 
+		reset_control_deassert(csi2rx->pixel_rst[i]);
+
 		writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF,
 		       csi2rx->base + CSI2RX_STREAM_CFG_REG(i));
 
@@ -169,6 +176,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
 	if (ret)
 		goto err_disable_pixclk;
 
+	reset_control_deassert(csi2rx->sys_rst);
 	clk_disable_unprepare(csi2rx->p_clk);
 
 	return 0;
@@ -188,14 +196,17 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
 	unsigned int i;
 
 	clk_prepare_enable(csi2rx->p_clk);
+	reset_control_assert(csi2rx->sys_rst);
 	clk_disable_unprepare(csi2rx->sys_clk);
 
 	for (i = 0; i < csi2rx->max_streams; i++) {
 		writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
 
+		reset_control_assert(csi2rx->pixel_rst[i]);
 		clk_disable_unprepare(csi2rx->pixel_clk[i]);
 	}
 
+	reset_control_assert(csi2rx->p_rst);
 	clk_disable_unprepare(csi2rx->p_clk);
 
 	if (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
@@ -299,6 +310,17 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
 		return PTR_ERR(csi2rx->p_clk);
 	}
 
+	csi2rx->sys_rst =
+		devm_reset_control_get_optional_exclusive(&pdev->dev,
+							  "sys_rst");
+	if (IS_ERR(csi2rx->sys_rst))
+		return PTR_ERR(csi2rx->sys_rst);
+
+	csi2rx->p_rst =
+		devm_reset_control_get_optional_exclusive(&pdev->dev, "p_rst");
+	if (IS_ERR(csi2rx->p_rst))
+		return PTR_ERR(csi2rx->p_rst);
+
 	csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy");
 	if (IS_ERR(csi2rx->dphy)) {
 		dev_err(&pdev->dev, "Couldn't get external D-PHY\n");
@@ -350,6 +372,7 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
 
 	for (i = 0; i < csi2rx->max_streams; i++) {
 		char clk_name[16];
+		char rst_name[16];
 
 		snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i);
 		csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name);
@@ -357,6 +380,13 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
 			dev_err(&pdev->dev, "Couldn't get clock %s\n", clk_name);
 			return PTR_ERR(csi2rx->pixel_clk[i]);
 		}
+
+		snprintf(rst_name, sizeof(rst_name), "pixel_if%u_rst", i);
+		csi2rx->pixel_rst[i] =
+			devm_reset_control_get_optional_exclusive(&pdev->dev,
+								  rst_name);
+		if (IS_ERR(csi2rx->pixel_rst[i]))
+			return PTR_ERR(csi2rx->pixel_rst[i]);
 	}
 
 	return 0;
-- 
2.34.1

Re: [PATCH v3 6/9] media: cadence: Add operation on reset

Posted by Laurent Pinchart 2 years, 10 months ago

Hi Jack,

Thank you for the patch.

On Fri, Mar 31, 2023 at 08:18:23PM +0800, Jack Zhu wrote:
> Add operation on reset for Cadence MIPI-CSI2 RX Controller.
> 
> Signed-off-by: Jack Zhu <jack.zhu@starfivetech.com>
> ---
>  drivers/media/platform/cadence/cdns-csi2rx.c | 30 ++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
> index cc3ebb0d96f6..a1555cedb349 100644
> --- a/drivers/media/platform/cadence/cdns-csi2rx.c
> +++ b/drivers/media/platform/cadence/cdns-csi2rx.c
> @@ -13,6 +13,7 @@
>  #include <linux/of_graph.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <linux/reset.h>
>  #include <linux/slab.h>
>  
>  #include <media/v4l2-ctrls.h>
> @@ -68,6 +69,9 @@ struct csi2rx_priv {
>  	struct clk			*sys_clk;
>  	struct clk			*p_clk;
>  	struct clk			*pixel_clk[CSI2RX_STREAMS_MAX];
> +	struct reset_control		*sys_rst;
> +	struct reset_control		*p_rst;
> +	struct reset_control		*pixel_rst[CSI2RX_STREAMS_MAX];
>  	struct phy			*dphy;
>  
>  	u8				lanes[CSI2RX_LANES_MAX];
> @@ -112,6 +116,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
>  	if (ret)
>  		return ret;
>  
> +	reset_control_deassert(csi2rx->p_rst);
>  	csi2rx_reset(csi2rx);
>  
>  	reg = csi2rx->num_lanes << 8;
> @@ -154,6 +159,8 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
>  		if (ret)
>  			goto err_disable_pixclk;

The loop after the err_disable_pixclk label should assert the
pixel_rst[i] reset.

>  
> +		reset_control_deassert(csi2rx->pixel_rst[i]);
> +
>  		writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF,
>  		       csi2rx->base + CSI2RX_STREAM_CFG_REG(i));
>  
> @@ -169,6 +176,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
>  	if (ret)
>  		goto err_disable_pixclk;
>  
> +	reset_control_deassert(csi2rx->sys_rst);
>  	clk_disable_unprepare(csi2rx->p_clk);
>  
>  	return 0;
> @@ -188,14 +196,17 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
>  	unsigned int i;
>  
>  	clk_prepare_enable(csi2rx->p_clk);
> +	reset_control_assert(csi2rx->sys_rst);
>  	clk_disable_unprepare(csi2rx->sys_clk);
>  
>  	for (i = 0; i < csi2rx->max_streams; i++) {
>  		writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
>  
> +		reset_control_assert(csi2rx->pixel_rst[i]);
>  		clk_disable_unprepare(csi2rx->pixel_clk[i]);
>  	}
>  
> +	reset_control_assert(csi2rx->p_rst);
>  	clk_disable_unprepare(csi2rx->p_clk);
>  
>  	if (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
> @@ -299,6 +310,17 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
>  		return PTR_ERR(csi2rx->p_clk);
>  	}
>  
> +	csi2rx->sys_rst =
> +		devm_reset_control_get_optional_exclusive(&pdev->dev,
> +							  "sys_rst");

You can write this on two lines:

	csi2rx->sys_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
								    "sys_rst");
> +	if (IS_ERR(csi2rx->sys_rst))
> +		return PTR_ERR(csi2rx->sys_rst);
> +
> +	csi2rx->p_rst =
> +		devm_reset_control_get_optional_exclusive(&pdev->dev, "p_rst");

And here,

	csi2rx->p_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
								  "p_rst");

would be the same number of lines but more readable in my opinion.

> +	if (IS_ERR(csi2rx->p_rst))
> +		return PTR_ERR(csi2rx->p_rst);
> +
>  	csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy");
>  	if (IS_ERR(csi2rx->dphy)) {
>  		dev_err(&pdev->dev, "Couldn't get external D-PHY\n");
> @@ -350,6 +372,7 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
>  
>  	for (i = 0; i < csi2rx->max_streams; i++) {
>  		char clk_name[16];
> +		char rst_name[16];

You don't need two variables, you can rename clk_name to name, and use
it for both clk and rst.

With these small issues addressed you can add my

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

in the next version.

>  
>  		snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i);
>  		csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name);
> @@ -357,6 +380,13 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
>  			dev_err(&pdev->dev, "Couldn't get clock %s\n", clk_name);
>  			return PTR_ERR(csi2rx->pixel_clk[i]);
>  		}
> +
> +		snprintf(rst_name, sizeof(rst_name), "pixel_if%u_rst", i);
> +		csi2rx->pixel_rst[i] =
> +			devm_reset_control_get_optional_exclusive(&pdev->dev,
> +								  rst_name);
> +		if (IS_ERR(csi2rx->pixel_rst[i]))
> +			return PTR_ERR(csi2rx->pixel_rst[i]);
>  	}
>  
>  	return 0;

-- 
Regards,

Laurent Pinchart

Re: [PATCH v3 6/9] media: cadence: Add operation on reset

Posted by Jack Zhu 2 years, 10 months ago


On 2023/4/4 13:06, Laurent Pinchart wrote:
> Hi Jack,
> 
> Thank you for the patch.
> 
> On Fri, Mar 31, 2023 at 08:18:23PM +0800, Jack Zhu wrote:
>> Add operation on reset for Cadence MIPI-CSI2 RX Controller.
>> 
>> Signed-off-by: Jack Zhu <jack.zhu@starfivetech.com>
>> ---
>>  drivers/media/platform/cadence/cdns-csi2rx.c | 30 ++++++++++++++++++++
>>  1 file changed, 30 insertions(+)
>> 
>> diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
>> index cc3ebb0d96f6..a1555cedb349 100644
>> --- a/drivers/media/platform/cadence/cdns-csi2rx.c
>> +++ b/drivers/media/platform/cadence/cdns-csi2rx.c
>> @@ -13,6 +13,7 @@
>>  #include <linux/of_graph.h>
>>  #include <linux/phy/phy.h>
>>  #include <linux/platform_device.h>
>> +#include <linux/reset.h>
>>  #include <linux/slab.h>
>>  
>>  #include <media/v4l2-ctrls.h>
>> @@ -68,6 +69,9 @@ struct csi2rx_priv {
>>  	struct clk			*sys_clk;
>>  	struct clk			*p_clk;
>>  	struct clk			*pixel_clk[CSI2RX_STREAMS_MAX];
>> +	struct reset_control		*sys_rst;
>> +	struct reset_control		*p_rst;
>> +	struct reset_control		*pixel_rst[CSI2RX_STREAMS_MAX];
>>  	struct phy			*dphy;
>>  
>>  	u8				lanes[CSI2RX_LANES_MAX];
>> @@ -112,6 +116,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
>>  	if (ret)
>>  		return ret;
>>  
>> +	reset_control_deassert(csi2rx->p_rst);
>>  	csi2rx_reset(csi2rx);
>>  
>>  	reg = csi2rx->num_lanes << 8;
>> @@ -154,6 +159,8 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
>>  		if (ret)
>>  			goto err_disable_pixclk;
> 
> The loop after the err_disable_pixclk label should assert the
> pixel_rst[i] reset.
> 

OK, I will fix it.

>>  
>> +		reset_control_deassert(csi2rx->pixel_rst[i]);
>> +
>>  		writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF,
>>  		       csi2rx->base + CSI2RX_STREAM_CFG_REG(i));
>>  
>> @@ -169,6 +176,7 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
>>  	if (ret)
>>  		goto err_disable_pixclk;
>>  
>> +	reset_control_deassert(csi2rx->sys_rst);
>>  	clk_disable_unprepare(csi2rx->p_clk);
>>  
>>  	return 0;
>> @@ -188,14 +196,17 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
>>  	unsigned int i;
>>  
>>  	clk_prepare_enable(csi2rx->p_clk);
>> +	reset_control_assert(csi2rx->sys_rst);
>>  	clk_disable_unprepare(csi2rx->sys_clk);
>>  
>>  	for (i = 0; i < csi2rx->max_streams; i++) {
>>  		writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i));
>>  
>> +		reset_control_assert(csi2rx->pixel_rst[i]);
>>  		clk_disable_unprepare(csi2rx->pixel_clk[i]);
>>  	}
>>  
>> +	reset_control_assert(csi2rx->p_rst);
>>  	clk_disable_unprepare(csi2rx->p_clk);
>>  
>>  	if (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
>> @@ -299,6 +310,17 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
>>  		return PTR_ERR(csi2rx->p_clk);
>>  	}
>>  
>> +	csi2rx->sys_rst =
>> +		devm_reset_control_get_optional_exclusive(&pdev->dev,
>> +							  "sys_rst");
> 
> You can write this on two lines:
> 
> 	csi2rx->sys_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
> 								    "sys_rst");

OK, I will modify it.

>> +	if (IS_ERR(csi2rx->sys_rst))
>> +		return PTR_ERR(csi2rx->sys_rst);
>> +
>> +	csi2rx->p_rst =
>> +		devm_reset_control_get_optional_exclusive(&pdev->dev, "p_rst");
> 
> And here,
> 
> 	csi2rx->p_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
> 								  "p_rst");
> 
> would be the same number of lines but more readable in my opinion.
> 

OK, I will modify it.

>> +	if (IS_ERR(csi2rx->p_rst))
>> +		return PTR_ERR(csi2rx->p_rst);
>> +
>>  	csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy");
>>  	if (IS_ERR(csi2rx->dphy)) {
>>  		dev_err(&pdev->dev, "Couldn't get external D-PHY\n");
>> @@ -350,6 +372,7 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
>>  
>>  	for (i = 0; i < csi2rx->max_streams; i++) {
>>  		char clk_name[16];
>> +		char rst_name[16];
> 
> You don't need two variables, you can rename clk_name to name, and use
> it for both clk and rst.
> 

OK, I will fix it.

> With these small issues addressed you can add my
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
> in the next version.
>
OK. Thank you for your review.

>>  
>>  		snprintf(clk_name, sizeof(clk_name), "pixel_if%u_clk", i);
>>  		csi2rx->pixel_clk[i] = devm_clk_get(&pdev->dev, clk_name);
>> @@ -357,6 +380,13 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
>>  			dev_err(&pdev->dev, "Couldn't get clock %s\n", clk_name);
>>  			return PTR_ERR(csi2rx->pixel_clk[i]);
>>  		}
>> +
>> +		snprintf(rst_name, sizeof(rst_name), "pixel_if%u_rst", i);
>> +		csi2rx->pixel_rst[i] =
>> +			devm_reset_control_get_optional_exclusive(&pdev->dev,
>> +								  rst_name);
>> +		if (IS_ERR(csi2rx->pixel_rst[i]))
>> +			return PTR_ERR(csi2rx->pixel_rst[i]);
>>  	}
>>  
>>  	return 0;
>