Patchwork [5/7] usb: phy: tegra: get ULPI reset GPIO info using DT.

login
register
mail settings
Submitter Venu Byravarasu
Date March 18, 2013, 12:29 p.m.
Message ID <1363609781-4045-6-git-send-email-vbyravarasu@nvidia.com>
Download mbox | patch
Permalink /patch/228484/
State Superseded, archived
Headers show

Comments

Venu Byravarasu - March 18, 2013, 12:29 p.m.
As GPIO information is avail through DT, used it to get Tegra ULPI
reset GPIO number. Added a new member to tegra_usb_phy structure to
store this number.

Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
---
 drivers/usb/phy/tegra_usb_phy.c   |   25 +++++++++++--------------
 include/linux/usb/tegra_usb_phy.h |    1 +
 2 files changed, 12 insertions(+), 14 deletions(-)
Sergei Shtylyov - March 18, 2013, 1:01 p.m.
Hello.

On 18-03-2013 16:29, Venu Byravarasu wrote:

> As GPIO information is avail through DT, used it to get Tegra ULPI
> reset GPIO number. Added a new member to tegra_usb_phy structure to
> store this number.

> Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
> ---
>   drivers/usb/phy/tegra_usb_phy.c   |   25 +++++++++++--------------
>   include/linux/usb/tegra_usb_phy.h |    1 +
>   2 files changed, 12 insertions(+), 14 deletions(-)

> diff --git a/drivers/usb/phy/tegra_usb_phy.c b/drivers/usb/phy/tegra_usb_phy.c
> index b5b2037..29c5ac4 100644
> --- a/drivers/usb/phy/tegra_usb_phy.c
> +++ b/drivers/usb/phy/tegra_usb_phy.c
[...]
> @@ -622,18 +619,18 @@ static int	tegra_phy_init(struct usb_phy *x)
[...]
> -		gpio_request(ulpi_config->reset_gpio, "ulpi_phy_reset_b");
> -		gpio_direction_output(ulpi_config->reset_gpio, 0);
> +		gpio_request(phy->reset_gpio, "ulpi_phy_reset_b");
> +		gpio_direction_output(phy->reset_gpio, 0);

    Why not use goio_request_one() instead of these two? Thought maybe it's a 
material of another patch...

WBR, Sergei

--
To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Venu Byravarasu - March 19, 2013, 4:12 a.m.
> -----Original Message-----
> From: linux-usb-owner@vger.kernel.org [mailto:linux-usb-
> owner@vger.kernel.org] On Behalf Of Sergei Shtylyov
> Sent: Monday, March 18, 2013 6:32 PM
> To: Venu Byravarasu
> Cc: gregkh@linuxfoundation.org; stern@rowland.harvard.edu;
> balbi@ti.com; linux-usb@vger.kernel.org; linux-kernel@vger.kernel.org;
> swarren@wwwdotorg.org; linux-tegra@vger.kernel.org; devicetree-
> discuss@lists.ozlabs.org
> Subject: Re: [PATCH 5/7] usb: phy: tegra: get ULPI reset GPIO info using DT.
> 
> Hello.
> 
> On 18-03-2013 16:29, Venu Byravarasu wrote:
> 
> > As GPIO information is avail through DT, used it to get Tegra ULPI
> > reset GPIO number. Added a new member to tegra_usb_phy structure to
> > store this number.
> 
> > Signed-off-by: Venu Byravarasu <vbyravarasu@nvidia.com>
> > ---
> >   drivers/usb/phy/tegra_usb_phy.c   |   25 +++++++++++--------------
> >   include/linux/usb/tegra_usb_phy.h |    1 +
> >   2 files changed, 12 insertions(+), 14 deletions(-)
> 
> > diff --git a/drivers/usb/phy/tegra_usb_phy.c
> b/drivers/usb/phy/tegra_usb_phy.c
> > index b5b2037..29c5ac4 100644
> > --- a/drivers/usb/phy/tegra_usb_phy.c
> > +++ b/drivers/usb/phy/tegra_usb_phy.c
> [...]
> > @@ -622,18 +619,18 @@ static int	tegra_phy_init(struct usb_phy *x)
> [...]
> > -		gpio_request(ulpi_config->reset_gpio, "ulpi_phy_reset_b");
> > -		gpio_direction_output(ulpi_config->reset_gpio, 0);
> > +		gpio_request(phy->reset_gpio, "ulpi_phy_reset_b");
> > +		gpio_direction_output(phy->reset_gpio, 0);
> 
>     Why not use goio_request_one() instead of these two? Thought maybe it's
> a
> material of another patch...

Sure, can take this up as part of next patch.
Thanks for the review. 

> 
> WBR, Sergei
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Stephen Warren - March 19, 2013, 8:03 p.m.
On 03/18/2013 06:29 AM, Venu Byravarasu wrote:
> As GPIO information is avail through DT, used it to get Tegra ULPI
> reset GPIO number. Added a new member to tegra_usb_phy structure to
> store this number.

> diff --git a/drivers/usb/phy/tegra_usb_phy.c b/drivers/usb/phy/tegra_usb_phy.c

> -	gpio_direction_output(config->reset_gpio, 0);
> +	gpio_direction_output(phy->reset_gpio, 0);
>  	msleep(5);
> -	gpio_direction_output(config->reset_gpio, 1);
> +	gpio_direction_output(phy->reset_gpio, 1);

That implies that the PHY reset signal is active-low. This should be
represented in the GPIO flags in the device tree. In other words,
instead of e.g.:

nvidia,phy-reset-gpio = <&gpio 169 0>; /* gpio PV1 */

you want:

nvidia,phy-reset-gpio = <&gpio 169 1>; /* gpio PV1 */

Flag 1 means active-low. See
Documentation/devicetree/bindings/gpio/nvidia,tegra20-gpio.txt. This is
a bug in the current device tree content, although it has no effect
since no code currently uses the GPIO flags from DT. I suggest creating
a separate patch to fix this, and inserting it between patch 1 and 2 of
the series.
--
To unsubscribe from this list: send the line "unsubscribe linux-tegra" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch

diff --git a/drivers/usb/phy/tegra_usb_phy.c b/drivers/usb/phy/tegra_usb_phy.c
index b5b2037..29c5ac4 100644
--- a/drivers/usb/phy/tegra_usb_phy.c
+++ b/drivers/usb/phy/tegra_usb_phy.c
@@ -541,11 +541,10 @@  static int ulpi_phy_power_on(struct tegra_usb_phy *phy)
 	int ret;
 	unsigned long val;
 	void __iomem *base = phy->regs;
-	struct tegra_ulpi_config *config = phy->config;
 
-	gpio_direction_output(config->reset_gpio, 0);
+	gpio_direction_output(phy->reset_gpio, 0);
 	msleep(5);
-	gpio_direction_output(config->reset_gpio, 1);
+	gpio_direction_output(phy->reset_gpio, 1);
 
 	clk_prepare_enable(phy->clk);
 	msleep(1);
@@ -603,10 +602,8 @@  static int ulpi_phy_power_on(struct tegra_usb_phy *phy)
 
 static int ulpi_phy_power_off(struct tegra_usb_phy *phy)
 {
-	struct tegra_ulpi_config *config = phy->config;
-
 	clk_disable(phy->clk);
-	return gpio_direction_output(config->reset_gpio, 0);
+	return gpio_direction_output(phy->reset_gpio, 0);
 }
 
 static int	tegra_phy_init(struct usb_phy *x)
@@ -622,18 +619,18 @@  static int	tegra_phy_init(struct usb_phy *x)
 			pr_err("%s: can't get ulpi clock\n", __func__);
 			return PTR_ERR(phy->clk);
 		}
-		if (!gpio_is_valid(ulpi_config->reset_gpio))
-			ulpi_config->reset_gpio =
-				of_get_named_gpio(phy->dev->of_node,
-						  "nvidia,phy-reset-gpio", 0);
-		if (!gpio_is_valid(ulpi_config->reset_gpio)) {
+
+		phy->reset_gpio =
+			of_get_named_gpio(phy->dev->of_node,
+					  "nvidia,phy-reset-gpio", 0);
+		if (!gpio_is_valid(phy->reset_gpio)) {
 			pr_err("%s: invalid reset gpio: %d\n", __func__,
-			       ulpi_config->reset_gpio);
+			       phy->reset_gpio);
 			err = -EINVAL;
 			goto err1;
 		}
-		gpio_request(ulpi_config->reset_gpio, "ulpi_phy_reset_b");
-		gpio_direction_output(ulpi_config->reset_gpio, 0);
+		gpio_request(phy->reset_gpio, "ulpi_phy_reset_b");
+		gpio_direction_output(phy->reset_gpio, 0);
 		phy->ulpi = otg_ulpi_create(&ulpi_viewport_access_ops, 0);
 		phy->ulpi->io_priv = phy->regs + ULPI_VIEWPORT;
 	} else {
diff --git a/include/linux/usb/tegra_usb_phy.h b/include/linux/usb/tegra_usb_phy.h
index a7af923..6cfb8f1 100644
--- a/include/linux/usb/tegra_usb_phy.h
+++ b/include/linux/usb/tegra_usb_phy.h
@@ -62,6 +62,7 @@  struct tegra_usb_phy {
 	struct device *dev;
 	bool is_legacy_phy;
 	bool is_ulpi_phy;
+	int reset_gpio;
 };
 
 struct tegra_usb_phy *tegra_usb_phy_open(struct device *dev, int instance,