diff mbox

[2/9] usb: phy: nop: Don't use regulator framework for RESET line

Message ID 1376488693-31659-3-git-send-email-rogerq@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Roger Quadros Aug. 14, 2013, 1:58 p.m. UTC
Modelling the RESET line as a regulator supply wasn't a good idea
as it kind of abuses the regulator framework and also makes adaptation
code more complex.

Instead, manage the RESET gpio line directly in the driver. Update
the device tree binding information.

This also makes us easy to migrate to a dedicated GPIO RESET controller
whenever it becomes available.

Signed-off-by: Roger Quadros <rogerq@ti.com>
---
 .../devicetree/bindings/usb/usb-nop-xceiv.txt      |    7 +--
 drivers/usb/phy/phy-nop.c                          |   48 ++++++++++++--------
 2 files changed, 32 insertions(+), 23 deletions(-)

Comments

Philipp Zabel Aug. 14, 2013, 3:27 p.m. UTC | #1
Hi Roger,

Am Mittwoch, den 14.08.2013, 16:58 +0300 schrieb Roger Quadros:
> Modelling the RESET line as a regulator supply wasn't a good idea
> as it kind of abuses the regulator framework and also makes adaptation
> code more complex.
> 
> Instead, manage the RESET gpio line directly in the driver. Update
> the device tree binding information.
> 
> This also makes us easy to migrate to a dedicated GPIO RESET controller
> whenever it becomes available.
> 
> Signed-off-by: Roger Quadros <rogerq@ti.com>

using the reset-gpios property
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>

> ---
>  .../devicetree/bindings/usb/usb-nop-xceiv.txt      |    7 +--
>  drivers/usb/phy/phy-nop.c                          |   48 ++++++++++++--------
>  2 files changed, 32 insertions(+), 23 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
> index d7e2726..5535f3b 100644
> --- a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
> +++ b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
> @@ -15,7 +15,7 @@ Optional properties:
>  
>  - vcc-supply: phandle to the regulator that provides RESET to the PHY.
>  
> -- reset-supply: phandle to the regulator that provides power to the PHY.
> +- reset-gpios: Should specify the GPIO for reset.
>
>  Example:
>  
> @@ -25,10 +25,9 @@ Example:
>  		clocks = <&osc 0>;
>  		clock-names = "main_clk";
>  		vcc-supply = <&hsusb1_vcc_regulator>;
> -		reset-supply = <&hsusb1_reset_regulator>;
> +		reset-gpios = <&gpio1 7>;

Yes, although the example should probably include GPIO_ACTIVE_LOW or
GPIO_ACTIVE_HIGH flags.

>  	};
>  
>  hsusb1_phy is a NOP USB PHY device that gets its clock from an oscillator
>  and expects that clock to be configured to 19.2MHz by the NOP PHY driver.
> -hsusb1_vcc_regulator provides power to the PHY and hsusb1_reset_regulator
> -controls RESET.
> +hsusb1_vcc_regulator provides power to the PHY and GPIO 7 controls RESET.
> diff --git a/drivers/usb/phy/phy-nop.c b/drivers/usb/phy/phy-nop.c
> index 55445e5d..af5e1a6 100644
> --- a/drivers/usb/phy/phy-nop.c
> +++ b/drivers/usb/phy/phy-nop.c
> @@ -35,6 +35,9 @@
>  #include <linux/clk.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/of.h>
> +#include <linux/of_gpio.h>
> +#include <linux/gpio.h>
> +#include <linux/delay.h>
>  
>  struct nop_usb_xceiv {
>  	struct usb_phy phy;
> @@ -42,6 +45,7 @@ struct nop_usb_xceiv {
>  	struct clk *clk;
>  	struct regulator *vcc;
>  	struct regulator *reset;
> +	int gpio_reset;
>  };
>  
>  static struct platform_device *pd;
> @@ -70,6 +74,15 @@ static int nop_set_suspend(struct usb_phy *x, int suspend)
>  	return 0;
>  }
>  
> +static void nop_gpio_reset(int gpio, int state)
> +{
> +	if (gpio_is_valid(gpio))
> +		gpio_set_value(gpio, state);
> +
> +	if (state)
> +		usleep_range(10000, 20000);
> +}
> +
>  static int nop_init(struct usb_phy *phy)
>  {
>  	struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
> @@ -82,11 +95,8 @@ static int nop_init(struct usb_phy *phy)
>  	if (!IS_ERR(nop->clk))
>  		clk_enable(nop->clk);
>  
> -	if (!IS_ERR(nop->reset)) {
> -		/* De-assert RESET */
> -		if (regulator_enable(nop->reset))
> -			dev_err(phy->dev, "Failed to de-assert reset\n");
> -	}
> +	/* De-assert RESET */
> +	nop_gpio_reset(nop->gpio_reset, 1);
>  
>  	return 0;
>  }
> @@ -95,11 +105,8 @@ static void nop_shutdown(struct usb_phy *phy)
>  {
>  	struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
>  
> -	if (!IS_ERR(nop->reset)) {
> -		/* Assert RESET */
> -		if (regulator_disable(nop->reset))
> -			dev_err(phy->dev, "Failed to assert reset\n");
> -	}
> +	/* Assert RESET */
> +	nop_gpio_reset(nop->gpio_reset, 0);
>  
>  	if (!IS_ERR(nop->clk))
>  		clk_disable(nop->clk);
> @@ -148,7 +155,6 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>  	int err;
>  	u32 clk_rate = 0;
>  	bool needs_vcc = false;
> -	bool needs_reset = false;
>  
>  	nop = devm_kzalloc(&pdev->dev, sizeof(*nop), GFP_KERNEL);
>  	if (!nop)
> @@ -166,13 +172,15 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>  			clk_rate = 0;
>  
>  		needs_vcc = of_property_read_bool(node, "vcc-supply");
> -		needs_reset = of_property_read_bool(node, "reset-supply");
> +		nop->gpio_reset = of_get_named_gpio(node, "reset-gpios", 0);

I'd suggest to use of_get_named_gpio_flags to also obtain the polarity
from the flags.

> +		if (nop->gpio_reset == -EPROBE_DEFER)
> +			return -EPROBE_DEFER;
>  
>  	} else if (pdata) {
>  		type = pdata->type;
>  		clk_rate = pdata->clk_rate;
>  		needs_vcc = pdata->needs_vcc;
> -		needs_reset = pdata->needs_reset;
> +		nop->gpio_reset = pdata->gpio_reset;
>  	}
>  
>  	nop->clk = devm_clk_get(&pdev->dev, "main_clk");
> @@ -205,12 +213,14 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>  			return -EPROBE_DEFER;
>  	}
>  
> -	nop->reset = devm_regulator_get(&pdev->dev, "reset");
> -	if (IS_ERR(nop->reset)) {
> -		dev_dbg(&pdev->dev, "Error getting reset regulator: %ld\n",
> -					PTR_ERR(nop->reset));
> -		if (needs_reset)
> -			return -EPROBE_DEFER;
> +	if (gpio_is_valid(nop->gpio_reset)) {
> +		err = devm_gpio_request_one(dev, nop->gpio_reset,
> +					    GPIOF_OUT_INIT_HIGH, dev_name(dev));
> +		if (err) {
> +			dev_err(dev, "Error requesting RESET GPIO %d\n",
> +					nop->gpio_reset);
> +			return err;
> +		}
>  	}
>  
>  	nop->dev		= &pdev->dev;

regards
Philipp

--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Roger Quadros Aug. 15, 2013, 8:49 a.m. UTC | #2
On 08/14/2013 06:27 PM, Philipp Zabel wrote:
> Hi Roger,
> 
> Am Mittwoch, den 14.08.2013, 16:58 +0300 schrieb Roger Quadros:
>> Modelling the RESET line as a regulator supply wasn't a good idea
>> as it kind of abuses the regulator framework and also makes adaptation
>> code more complex.
>>
>> Instead, manage the RESET gpio line directly in the driver. Update
>> the device tree binding information.
>>
>> This also makes us easy to migrate to a dedicated GPIO RESET controller
>> whenever it becomes available.
>>
>> Signed-off-by: Roger Quadros <rogerq@ti.com>
> 
> using the reset-gpios property
> Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
> 
>> ---
>>  .../devicetree/bindings/usb/usb-nop-xceiv.txt      |    7 +--
>>  drivers/usb/phy/phy-nop.c                          |   48 ++++++++++++--------
>>  2 files changed, 32 insertions(+), 23 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> index d7e2726..5535f3b 100644
>> --- a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> +++ b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> @@ -15,7 +15,7 @@ Optional properties:
>>  
>>  - vcc-supply: phandle to the regulator that provides RESET to the PHY.
>>  
>> -- reset-supply: phandle to the regulator that provides power to the PHY.
>> +- reset-gpios: Should specify the GPIO for reset.
>>
>>  Example:
>>  
>> @@ -25,10 +25,9 @@ Example:
>>  		clocks = <&osc 0>;
>>  		clock-names = "main_clk";
>>  		vcc-supply = <&hsusb1_vcc_regulator>;
>> -		reset-supply = <&hsusb1_reset_regulator>;
>> +		reset-gpios = <&gpio1 7>;
> 
> Yes, although the example should probably include GPIO_ACTIVE_LOW or
> GPIO_ACTIVE_HIGH flags.
> 
OK.

>>  	};
>>  
>>  hsusb1_phy is a NOP USB PHY device that gets its clock from an oscillator
>>  and expects that clock to be configured to 19.2MHz by the NOP PHY driver.
>> -hsusb1_vcc_regulator provides power to the PHY and hsusb1_reset_regulator
>> -controls RESET.
>> +hsusb1_vcc_regulator provides power to the PHY and GPIO 7 controls RESET.
>> diff --git a/drivers/usb/phy/phy-nop.c b/drivers/usb/phy/phy-nop.c
>> index 55445e5d..af5e1a6 100644
>> --- a/drivers/usb/phy/phy-nop.c
>> +++ b/drivers/usb/phy/phy-nop.c
>> @@ -35,6 +35,9 @@
>>  #include <linux/clk.h>
>>  #include <linux/regulator/consumer.h>
>>  #include <linux/of.h>
>> +#include <linux/of_gpio.h>
>> +#include <linux/gpio.h>
>> +#include <linux/delay.h>
>>  
>>  struct nop_usb_xceiv {
>>  	struct usb_phy phy;
>> @@ -42,6 +45,7 @@ struct nop_usb_xceiv {
>>  	struct clk *clk;
>>  	struct regulator *vcc;
>>  	struct regulator *reset;
>> +	int gpio_reset;
>>  };
>>  
>>  static struct platform_device *pd;
>> @@ -70,6 +74,15 @@ static int nop_set_suspend(struct usb_phy *x, int suspend)
>>  	return 0;
>>  }
>>  
>> +static void nop_gpio_reset(int gpio, int state)
>> +{
>> +	if (gpio_is_valid(gpio))
>> +		gpio_set_value(gpio, state);
>> +
>> +	if (state)
>> +		usleep_range(10000, 20000);
>> +}
>> +
>>  static int nop_init(struct usb_phy *phy)
>>  {
>>  	struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
>> @@ -82,11 +95,8 @@ static int nop_init(struct usb_phy *phy)
>>  	if (!IS_ERR(nop->clk))
>>  		clk_enable(nop->clk);
>>  
>> -	if (!IS_ERR(nop->reset)) {
>> -		/* De-assert RESET */
>> -		if (regulator_enable(nop->reset))
>> -			dev_err(phy->dev, "Failed to de-assert reset\n");
>> -	}
>> +	/* De-assert RESET */
>> +	nop_gpio_reset(nop->gpio_reset, 1);
>>  
>>  	return 0;
>>  }
>> @@ -95,11 +105,8 @@ static void nop_shutdown(struct usb_phy *phy)
>>  {
>>  	struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
>>  
>> -	if (!IS_ERR(nop->reset)) {
>> -		/* Assert RESET */
>> -		if (regulator_disable(nop->reset))
>> -			dev_err(phy->dev, "Failed to assert reset\n");
>> -	}
>> +	/* Assert RESET */
>> +	nop_gpio_reset(nop->gpio_reset, 0);
>>  
>>  	if (!IS_ERR(nop->clk))
>>  		clk_disable(nop->clk);
>> @@ -148,7 +155,6 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>>  	int err;
>>  	u32 clk_rate = 0;
>>  	bool needs_vcc = false;
>> -	bool needs_reset = false;
>>  
>>  	nop = devm_kzalloc(&pdev->dev, sizeof(*nop), GFP_KERNEL);
>>  	if (!nop)
>> @@ -166,13 +172,15 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>>  			clk_rate = 0;
>>  
>>  		needs_vcc = of_property_read_bool(node, "vcc-supply");
>> -		needs_reset = of_property_read_bool(node, "reset-supply");
>> +		nop->gpio_reset = of_get_named_gpio(node, "reset-gpios", 0);
> 
> I'd suggest to use of_get_named_gpio_flags to also obtain the polarity
> from the flags.

OK. good point.

> 
>> +		if (nop->gpio_reset == -EPROBE_DEFER)
>> +			return -EPROBE_DEFER;
>>  
>>  	} else if (pdata) {
>>  		type = pdata->type;
>>  		clk_rate = pdata->clk_rate;
>>  		needs_vcc = pdata->needs_vcc;
>> -		needs_reset = pdata->needs_reset;
>> +		nop->gpio_reset = pdata->gpio_reset;
>>  	}
>>  
>>  	nop->clk = devm_clk_get(&pdev->dev, "main_clk");
>> @@ -205,12 +213,14 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>>  			return -EPROBE_DEFER;
>>  	}
>>  
>> -	nop->reset = devm_regulator_get(&pdev->dev, "reset");
>> -	if (IS_ERR(nop->reset)) {
>> -		dev_dbg(&pdev->dev, "Error getting reset regulator: %ld\n",
>> -					PTR_ERR(nop->reset));
>> -		if (needs_reset)
>> -			return -EPROBE_DEFER;
>> +	if (gpio_is_valid(nop->gpio_reset)) {
>> +		err = devm_gpio_request_one(dev, nop->gpio_reset,
>> +					    GPIOF_OUT_INIT_HIGH, dev_name(dev));
>> +		if (err) {
>> +			dev_err(dev, "Error requesting RESET GPIO %d\n",
>> +					nop->gpio_reset);
>> +			return err;
>> +		}
>>  	}
>>  
>>  	nop->dev		= &pdev->dev;
> 

Thanks for the review. I'll send a v2.

cheers,
-roger
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
index d7e2726..5535f3b 100644
--- a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
+++ b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
@@ -15,7 +15,7 @@  Optional properties:
 
 - vcc-supply: phandle to the regulator that provides RESET to the PHY.
 
-- reset-supply: phandle to the regulator that provides power to the PHY.
+- reset-gpios: Should specify the GPIO for reset.
 
 Example:
 
@@ -25,10 +25,9 @@  Example:
 		clocks = <&osc 0>;
 		clock-names = "main_clk";
 		vcc-supply = <&hsusb1_vcc_regulator>;
-		reset-supply = <&hsusb1_reset_regulator>;
+		reset-gpios = <&gpio1 7>;
 	};
 
 hsusb1_phy is a NOP USB PHY device that gets its clock from an oscillator
 and expects that clock to be configured to 19.2MHz by the NOP PHY driver.
-hsusb1_vcc_regulator provides power to the PHY and hsusb1_reset_regulator
-controls RESET.
+hsusb1_vcc_regulator provides power to the PHY and GPIO 7 controls RESET.
diff --git a/drivers/usb/phy/phy-nop.c b/drivers/usb/phy/phy-nop.c
index 55445e5d..af5e1a6 100644
--- a/drivers/usb/phy/phy-nop.c
+++ b/drivers/usb/phy/phy-nop.c
@@ -35,6 +35,9 @@ 
 #include <linux/clk.h>
 #include <linux/regulator/consumer.h>
 #include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
 
 struct nop_usb_xceiv {
 	struct usb_phy phy;
@@ -42,6 +45,7 @@  struct nop_usb_xceiv {
 	struct clk *clk;
 	struct regulator *vcc;
 	struct regulator *reset;
+	int gpio_reset;
 };
 
 static struct platform_device *pd;
@@ -70,6 +74,15 @@  static int nop_set_suspend(struct usb_phy *x, int suspend)
 	return 0;
 }
 
+static void nop_gpio_reset(int gpio, int state)
+{
+	if (gpio_is_valid(gpio))
+		gpio_set_value(gpio, state);
+
+	if (state)
+		usleep_range(10000, 20000);
+}
+
 static int nop_init(struct usb_phy *phy)
 {
 	struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
@@ -82,11 +95,8 @@  static int nop_init(struct usb_phy *phy)
 	if (!IS_ERR(nop->clk))
 		clk_enable(nop->clk);
 
-	if (!IS_ERR(nop->reset)) {
-		/* De-assert RESET */
-		if (regulator_enable(nop->reset))
-			dev_err(phy->dev, "Failed to de-assert reset\n");
-	}
+	/* De-assert RESET */
+	nop_gpio_reset(nop->gpio_reset, 1);
 
 	return 0;
 }
@@ -95,11 +105,8 @@  static void nop_shutdown(struct usb_phy *phy)
 {
 	struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
 
-	if (!IS_ERR(nop->reset)) {
-		/* Assert RESET */
-		if (regulator_disable(nop->reset))
-			dev_err(phy->dev, "Failed to assert reset\n");
-	}
+	/* Assert RESET */
+	nop_gpio_reset(nop->gpio_reset, 0);
 
 	if (!IS_ERR(nop->clk))
 		clk_disable(nop->clk);
@@ -148,7 +155,6 @@  static int nop_usb_xceiv_probe(struct platform_device *pdev)
 	int err;
 	u32 clk_rate = 0;
 	bool needs_vcc = false;
-	bool needs_reset = false;
 
 	nop = devm_kzalloc(&pdev->dev, sizeof(*nop), GFP_KERNEL);
 	if (!nop)
@@ -166,13 +172,15 @@  static int nop_usb_xceiv_probe(struct platform_device *pdev)
 			clk_rate = 0;
 
 		needs_vcc = of_property_read_bool(node, "vcc-supply");
-		needs_reset = of_property_read_bool(node, "reset-supply");
+		nop->gpio_reset = of_get_named_gpio(node, "reset-gpios", 0);
+		if (nop->gpio_reset == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
 
 	} else if (pdata) {
 		type = pdata->type;
 		clk_rate = pdata->clk_rate;
 		needs_vcc = pdata->needs_vcc;
-		needs_reset = pdata->needs_reset;
+		nop->gpio_reset = pdata->gpio_reset;
 	}
 
 	nop->clk = devm_clk_get(&pdev->dev, "main_clk");
@@ -205,12 +213,14 @@  static int nop_usb_xceiv_probe(struct platform_device *pdev)
 			return -EPROBE_DEFER;
 	}
 
-	nop->reset = devm_regulator_get(&pdev->dev, "reset");
-	if (IS_ERR(nop->reset)) {
-		dev_dbg(&pdev->dev, "Error getting reset regulator: %ld\n",
-					PTR_ERR(nop->reset));
-		if (needs_reset)
-			return -EPROBE_DEFER;
+	if (gpio_is_valid(nop->gpio_reset)) {
+		err = devm_gpio_request_one(dev, nop->gpio_reset,
+					    GPIOF_OUT_INIT_HIGH, dev_name(dev));
+		if (err) {
+			dev_err(dev, "Error requesting RESET GPIO %d\n",
+					nop->gpio_reset);
+			return err;
+		}
 	}
 
 	nop->dev		= &pdev->dev;