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[PATCH v6 1/5] usb: cdns3-ti: move reg writes to separate function

Théo Lebrun posted 5 patches 1 year ago
There is a newer version of this series
[PATCH v6 1/5] usb: cdns3-ti: move reg writes to separate function
Posted by Théo Lebrun 1 year ago 
The device probe function mixes management code and hardware
initialisation code. Extract the latter into an explicitly named
cdns_ti_reset_and_init_hw() function to clarify intent. It also will
allow easier transition to using runtime PM for triggering HW init.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
 drivers/usb/cdns3/cdns3-ti.c | 84 ++++++++++++++++++++++++--------------------
 1 file changed, 46 insertions(+), 38 deletions(-)

diff --git a/drivers/usb/cdns3/cdns3-ti.c b/drivers/usb/cdns3/cdns3-ti.c
index 040bb91e9c017d8298a7e251fd0e192a336e8a52..d704eb39820ad08a8774be7f00aa473c3ff267c0 100644
--- a/drivers/usb/cdns3/cdns3-ti.c
+++ b/drivers/usb/cdns3/cdns3-ti.c
@@ -58,6 +58,7 @@ struct cdns_ti {
 	unsigned vbus_divider:1;
 	struct clk *usb2_refclk;
 	struct clk *lpm_clk;
+	int usb2_refclk_rate_code;
 };
 
 static const int cdns_ti_rate_table[] = {	/* in KHZ */
@@ -98,15 +99,52 @@ static const struct of_dev_auxdata cdns_ti_auxdata[] = {
 	{},
 };
 
+static void cdns_ti_reset_and_init_hw(struct cdns_ti *data)
+{
+	u32 reg;
+
+	/* assert RESET */
+	reg = cdns_ti_readl(data, USBSS_W1);
+	reg &= ~USBSS_W1_PWRUP_RST;
+	cdns_ti_writel(data, USBSS_W1, reg);
+
+	/* set static config */
+	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
+	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
+	reg |= data->usb2_refclk_rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
+
+	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
+
+	if (data->vbus_divider)
+		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
+
+	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
+	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
+
+	/* set USB2_ONLY mode if requested */
+	reg = cdns_ti_readl(data, USBSS_W1);
+
+	if (data->usb2_only)
+		reg |= USBSS_W1_USB2_ONLY;
+
+	/* set default modestrap */
+	reg |= USBSS_W1_MODESTRAP_SEL;
+	reg &= ~USBSS_W1_MODESTRAP_MASK;
+	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
+	cdns_ti_writel(data, USBSS_W1, reg);
+
+	/* de-assert RESET */
+	reg |= USBSS_W1_PWRUP_RST;
+	cdns_ti_writel(data, USBSS_W1, reg);
+}
+
 static int cdns_ti_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct device_node *node = pdev->dev.of_node;
 	struct cdns_ti *data;
-	int error;
-	u32 reg;
-	int rate_code, i;
 	unsigned long rate;
+	int error, i;
 
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
@@ -146,7 +184,11 @@ static int cdns_ti_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	rate_code = i;
+	data->usb2_refclk_rate_code = i;
+	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
+	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
+
+	cdns_ti_reset_and_init_hw(data);
 
 	pm_runtime_enable(dev);
 	error = pm_runtime_get_sync(dev);
@@ -155,40 +197,6 @@ static int cdns_ti_probe(struct platform_device *pdev)
 		goto err;
 	}
 
-	/* assert RESET */
-	reg = cdns_ti_readl(data, USBSS_W1);
-	reg &= ~USBSS_W1_PWRUP_RST;
-	cdns_ti_writel(data, USBSS_W1, reg);
-
-	/* set static config */
-	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
-	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
-	reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
-
-	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
-	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
-	if (data->vbus_divider)
-		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
-
-	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
-	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
-
-	/* set USB2_ONLY mode if requested */
-	reg = cdns_ti_readl(data, USBSS_W1);
-	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
-	if (data->usb2_only)
-		reg |= USBSS_W1_USB2_ONLY;
-
-	/* set default modestrap */
-	reg |= USBSS_W1_MODESTRAP_SEL;
-	reg &= ~USBSS_W1_MODESTRAP_MASK;
-	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
-	cdns_ti_writel(data, USBSS_W1, reg);
-
-	/* de-assert RESET */
-	reg |= USBSS_W1_PWRUP_RST;
-	cdns_ti_writel(data, USBSS_W1, reg);
-
 	error = of_platform_populate(node, NULL, cdns_ti_auxdata, dev);
 	if (error) {
 		dev_err(dev, "failed to create children: %d\n", error);

-- 
2.47.1
Re: [PATCH v6 1/5] usb: cdns3-ti: move reg writes to separate function
Posted by Roger Quadros 1 year ago 

On 10/12/2024 19:13, Théo Lebrun wrote:
> The device probe function mixes management code and hardware
> initialisation code. Extract the latter into an explicitly named
> cdns_ti_reset_and_init_hw() function to clarify intent. It also will
> allow easier transition to using runtime PM for triggering HW init.
> 
> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> ---
>  drivers/usb/cdns3/cdns3-ti.c | 84 ++++++++++++++++++++++++--------------------
>  1 file changed, 46 insertions(+), 38 deletions(-)
> 
> diff --git a/drivers/usb/cdns3/cdns3-ti.c b/drivers/usb/cdns3/cdns3-ti.c
> index 040bb91e9c017d8298a7e251fd0e192a336e8a52..d704eb39820ad08a8774be7f00aa473c3ff267c0 100644
> --- a/drivers/usb/cdns3/cdns3-ti.c
> +++ b/drivers/usb/cdns3/cdns3-ti.c
> @@ -58,6 +58,7 @@ struct cdns_ti {
>  	unsigned vbus_divider:1;
>  	struct clk *usb2_refclk;
>  	struct clk *lpm_clk;
> +	int usb2_refclk_rate_code;
>  };
>  
>  static const int cdns_ti_rate_table[] = {	/* in KHZ */
> @@ -98,15 +99,52 @@ static const struct of_dev_auxdata cdns_ti_auxdata[] = {
>  	{},
>  };
>  
> +static void cdns_ti_reset_and_init_hw(struct cdns_ti *data)
> +{
> +	u32 reg;
> +
> +	/* assert RESET */
> +	reg = cdns_ti_readl(data, USBSS_W1);
> +	reg &= ~USBSS_W1_PWRUP_RST;
> +	cdns_ti_writel(data, USBSS_W1, reg);
> +
> +	/* set static config */
> +	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
> +	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
> +	reg |= data->usb2_refclk_rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
> +
> +	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
> +
new line not required?

> +	if (data->vbus_divider)
> +		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
> +
> +	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
> +	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
> +
> +	/* set USB2_ONLY mode if requested */
> +	reg = cdns_ti_readl(data, USBSS_W1);
> +
here too?

> +	if (data->usb2_only)
> +		reg |= USBSS_W1_USB2_ONLY;
> +
> +	/* set default modestrap */
> +	reg |= USBSS_W1_MODESTRAP_SEL;
> +	reg &= ~USBSS_W1_MODESTRAP_MASK;
> +	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
> +	cdns_ti_writel(data, USBSS_W1, reg);
> +
> +	/* de-assert RESET */
> +	reg |= USBSS_W1_PWRUP_RST;
> +	cdns_ti_writel(data, USBSS_W1, reg);
> +}
> +
>  static int cdns_ti_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct device_node *node = pdev->dev.of_node;
>  	struct cdns_ti *data;
> -	int error;
> -	u32 reg;
> -	int rate_code, i;
>  	unsigned long rate;
> +	int error, i;
>  
>  	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>  	if (!data)
> @@ -146,7 +184,11 @@ static int cdns_ti_probe(struct platform_device *pdev)
>  		return -EINVAL;
>  	}
>  
> -	rate_code = i;
> +	data->usb2_refclk_rate_code = i;
> +	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
> +	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
> +
> +	cdns_ti_reset_and_init_hw(data);
>  
>  	pm_runtime_enable(dev);
>  	error = pm_runtime_get_sync(dev);
> @@ -155,40 +197,6 @@ static int cdns_ti_probe(struct platform_device *pdev)
>  		goto err;
>  	}
>  
> -	/* assert RESET */
> -	reg = cdns_ti_readl(data, USBSS_W1);
> -	reg &= ~USBSS_W1_PWRUP_RST;
> -	cdns_ti_writel(data, USBSS_W1, reg);
> -
> -	/* set static config */
> -	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
> -	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
> -	reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
> -
> -	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
> -	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
> -	if (data->vbus_divider)
> -		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
> -
> -	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
> -	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
> -
> -	/* set USB2_ONLY mode if requested */
> -	reg = cdns_ti_readl(data, USBSS_W1);
> -	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
> -	if (data->usb2_only)
> -		reg |= USBSS_W1_USB2_ONLY;
> -
> -	/* set default modestrap */
> -	reg |= USBSS_W1_MODESTRAP_SEL;
> -	reg &= ~USBSS_W1_MODESTRAP_MASK;
> -	reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
> -	cdns_ti_writel(data, USBSS_W1, reg);
> -
> -	/* de-assert RESET */
> -	reg |= USBSS_W1_PWRUP_RST;
> -	cdns_ti_writel(data, USBSS_W1, reg);
> -
>  	error = of_platform_populate(node, NULL, cdns_ti_auxdata, dev);
>  	if (error) {
>  		dev_err(dev, "failed to create children: %d\n", error);
> 

Reviewed-by: Roger Quadros <rogerq@kernel.org>

-- 
cheers,
-roger

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