diff mbox series

[02/10] dma-engine: sun4i: Add has_reset option to quirk

Message ID 20241024064931.1144605-3-csokas.bence@prolan.hu (mailing list archive)
State New, archived
Headers show
Series [01/10] dma-engine: sun4i: Add a quirk to support different chips | expand

Commit Message

Csókás Bence Oct. 24, 2024, 6:49 a.m. UTC
From: Mesih Kilinc <mesihkilinc@gmail.com>

Allwinner suniv F1C100s has a reset bit for DMA in CCU. Sun4i do not
has this bit but in order to support suniv we need to add it. So add
support for reset bit.

Signed-off-by: Mesih Kilinc <mesihkilinc@gmail.com>
---
 drivers/dma/sun4i-dma.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

Comments

Philipp Zabel Oct. 24, 2024, 8:11 a.m. UTC | #1
On Do, 2024-10-24 at 08:49 +0200, Csókás, Bence wrote:
> From: Mesih Kilinc <mesihkilinc@gmail.com>
> 
> Allwinner suniv F1C100s has a reset bit for DMA in CCU. Sun4i do not
> has this bit but in order to support suniv we need to add it. So add
> support for reset bit.
> 
> Signed-off-by: Mesih Kilinc <mesihkilinc@gmail.com>
> ---
>  drivers/dma/sun4i-dma.c | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/drivers/dma/sun4i-dma.c b/drivers/dma/sun4i-dma.c
> index 5efbed7c546f..0b99b3884971 100644
> --- a/drivers/dma/sun4i-dma.c
> +++ b/drivers/dma/sun4i-dma.c
> @@ -15,6 +15,7 @@
>  #include <linux/of_dma.h>
>  #include <linux/of_device.h>
>  #include <linux/platform_device.h>
> +#include <linux/reset.h>
>  #include <linux/slab.h>
>  #include <linux/spinlock.h>
>  
> @@ -159,6 +160,7 @@ struct sun4i_dma_config {
>  	u8 ddma_drq_sdram;
>  
>  	u8 max_burst;
> +	bool has_reset;
>  };
>  
>  struct sun4i_dma_pchan {
> @@ -208,6 +210,7 @@ struct sun4i_dma_dev {
>  	int				irq;
>  	spinlock_t			lock;
>  	const struct sun4i_dma_config *cfg;
> +	struct reset_control *rst;
>  };
>  
>  static struct sun4i_dma_dev *to_sun4i_dma_dev(struct dma_device *dev)
> @@ -1215,6 +1218,15 @@ static int sun4i_dma_probe(struct platform_device *pdev)
>  		return PTR_ERR(priv->clk);
>  	}
>  
> +	if (priv->cfg->has_reset) {
> +		priv->rst = devm_reset_control_get_exclusive(&pdev->dev,
> +							       NULL);

Aligning to open parenthesis will make checkpatch --strict happy.

> +		if (IS_ERR(priv->rst)) {
> +			dev_err(&pdev->dev, "Failed to get reset control\n");

Consider using dev_err_probe() here.

> +			return PTR_ERR(priv->rst);
> +		}
> +	}
> +
>  	platform_set_drvdata(pdev, priv);
>  	spin_lock_init(&priv->lock);
>  
> @@ -1287,6 +1299,16 @@ static int sun4i_dma_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> +	/* Deassert the reset control */
> +	if (priv->rst) {
> +		ret = reset_control_deassert(priv->rst);
> +		if (ret) {
> +			dev_err(&pdev->dev,
> +				"Failed to deassert the reset control\n");
> +			goto err_clk_disable;
> +		}
> +	}

You can just call reset_control_deassert() unconditionally, it accepts
a NULL parameter:

  https://docs.kernel.org/driver-api/reset.html#c.reset_control_deassert


regards
Philipp
diff mbox series

Patch

diff --git a/drivers/dma/sun4i-dma.c b/drivers/dma/sun4i-dma.c
index 5efbed7c546f..0b99b3884971 100644
--- a/drivers/dma/sun4i-dma.c
+++ b/drivers/dma/sun4i-dma.c
@@ -15,6 +15,7 @@ 
 #include <linux/of_dma.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
@@ -159,6 +160,7 @@  struct sun4i_dma_config {
 	u8 ddma_drq_sdram;
 
 	u8 max_burst;
+	bool has_reset;
 };
 
 struct sun4i_dma_pchan {
@@ -208,6 +210,7 @@  struct sun4i_dma_dev {
 	int				irq;
 	spinlock_t			lock;
 	const struct sun4i_dma_config *cfg;
+	struct reset_control *rst;
 };
 
 static struct sun4i_dma_dev *to_sun4i_dma_dev(struct dma_device *dev)
@@ -1215,6 +1218,15 @@  static int sun4i_dma_probe(struct platform_device *pdev)
 		return PTR_ERR(priv->clk);
 	}
 
+	if (priv->cfg->has_reset) {
+		priv->rst = devm_reset_control_get_exclusive(&pdev->dev,
+							       NULL);
+		if (IS_ERR(priv->rst)) {
+			dev_err(&pdev->dev, "Failed to get reset control\n");
+			return PTR_ERR(priv->rst);
+		}
+	}
+
 	platform_set_drvdata(pdev, priv);
 	spin_lock_init(&priv->lock);
 
@@ -1287,6 +1299,16 @@  static int sun4i_dma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* Deassert the reset control */
+	if (priv->rst) {
+		ret = reset_control_deassert(priv->rst);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Failed to deassert the reset control\n");
+			goto err_clk_disable;
+		}
+	}
+
 	/*
 	 * Make sure the IRQs are all disabled and accounted for. The bootloader
 	 * likes to leave these dirty
@@ -1356,6 +1378,7 @@  static struct sun4i_dma_config sun4i_a10_dma_cfg = {
 	.ddma_drq_sdram		= SUN4I_DDMA_DRQ_TYPE_SDRAM,
 
 	.max_burst		= SUN4I_MAX_BURST,
+	.has_reset		= false,
 };
 
 static const struct of_device_id sun4i_dma_match[] = {