Re: [PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

[Alban]

On Tue, 2 Feb 2016 11:41:15 +0530
Kishon Vijay Abraham I  wrote:

> Hi,
> 
> On Friday 29 January 2016 01:22 AM, Alban Bedel wrote:
> > The ATH79 USB phy is very simple, it only have a reset. On some SoC a
> > second reset is used to force the phy in suspend mode regardless of the
> > USB controller status.
> > 
> > Signed-off-by: Alban Bedel 
> > ---
> > Changelog:
> > v2: * Rebased on the simple PHY driver
> > * Added myself as maintainer of the driver
> > ---
> >  MAINTAINERS |   8 +++
> >  drivers/phy/Kconfig |   8 +++
> >  drivers/phy/Makefile|   1 +
> >  drivers/phy/phy-ath79-usb.c | 116 
> > 
> >  4 files changed, 133 insertions(+)
> >  create mode 100644 drivers/phy/phy-ath79-usb.c
> > 
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 30aca4a..f536d52 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -1866,6 +1866,14 @@ S:   Maintained
> >  F: drivers/gpio/gpio-ath79.c
> >  F: Documentation/devicetree/bindings/gpio/gpio-ath79.txt
> >  
> > +ATHEROS 71XX/9XXX USB PHY DRIVER
> > +M: Alban Bedel 
> > +W: https://github.com/AlbanBedel/linux
> > +T: git git://github.com/AlbanBedel/linux
> > +S: Maintained
> > +F: drivers/phy/phy-ath79-usb.c
> > +F: Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
> > +
> >  ATHEROS ATH GENERIC UTILITIES
> >  M: "Luis R. Rodriguez" 
> >  L: linux-wirel...@vger.kernel.org
> > diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> > index efbaee4..6090c63 100644
> > --- a/drivers/phy/Kconfig
> > +++ b/drivers/phy/Kconfig
> > @@ -15,6 +15,14 @@ config GENERIC_PHY
> >   phy users can obtain reference to the PHY. All the users of this
> >   framework should select this config.
> >  
> > +config PHY_ATH79_USB
> > +   tristate "Atheros AR71XX/9XXX USB PHY driver"
> > +   depends on ATH79 || COMPILE_TEST
> > +   default y if USB_EHCI_HCD_PLATFORM
> > +   select PHY_SIMPLE
> > +   help
> > + Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
> > +
> >  config PHY_BERLIN_USB
> > tristate "Marvell Berlin USB PHY Driver"
> > depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
> > diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> > index 1cc7268..5c9ca5f 100644
> > --- a/drivers/phy/Makefile
> > +++ b/drivers/phy/Makefile
> > @@ -3,6 +3,7 @@
> >  #
> >  
> >  obj-$(CONFIG_GENERIC_PHY)  += phy-core.o
> > +obj-$(CONFIG_PHY_ATH79_USB)+= phy-ath79-usb.o
> >  obj-$(CONFIG_PHY_BERLIN_USB)   += phy-berlin-usb.o
> >  obj-$(CONFIG_PHY_BERLIN_SATA)  += phy-berlin-sata.o
> >  obj-$(CONFIG_PHY_DM816X_USB)   += phy-dm816x-usb.o
> > diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
> > new file mode 100644
> > index 000..ff49356
> > --- /dev/null
> > +++ b/drivers/phy/phy-ath79-usb.c
> > @@ -0,0 +1,116 @@
> > +/*
> > + * Copyright (C) 2015 Alban Bedel 
> 
> 2016?

I'll fix this one too.

> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +
> > +struct ath79_usb_phy {
> > +   struct simple_phy sphy;
> > +   struct reset_control *suspend_override;
> > +};
> > +
> > +static int ath79_usb_phy_power_on(struct phy *phy)
> > +{
> > +   struct ath79_usb_phy *priv = container_of(
> > +   phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
> > +   int err;
> > +
> > +   err = simple_phy_power_on(phy);
> 
> Why do you need a separate driver for ath79_usb? We should be able to directly
> use simple phy driver right?

The ath79 PHY controller misuse the reset controller to control a
suspend override. When this reset line is deasserted the PHY is forced
in suspend mode, for normal operations it must be asserted. In short
this extra reset is inverted compared to the normal use of a reset line.

To support that that in the simple driver we would first need to find a
way to support multiple resets. Not impossible, but not trivial either
as we would need to at least get a name list from somewhere. Then we
would need another scheme to indicate that this extra reset need to be
inverted, again possible but it would start be a bit hacky. All in all
that didn't sound like a good idea for something that is supposed to be
a "simple" driver, so a dedicated driver sounded like the best approach
for this case.

Alban

Re: [PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

[Alban]

On Tue, 2 Feb 2016 11:41:15 +0530
Kishon Vijay Abraham I  wrote:

> Hi,
> 
> On Friday 29 January 2016 01:22 AM, Alban Bedel wrote:
> > The ATH79 USB phy is very simple, it only have a reset. On some SoC a
> > second reset is used to force the phy in suspend mode regardless of the
> > USB controller status.
> > 
> > Signed-off-by: Alban Bedel 
> > ---
> > Changelog:
> > v2: * Rebased on the simple PHY driver
> > * Added myself as maintainer of the driver
> > ---
> >  MAINTAINERS |   8 +++
> >  drivers/phy/Kconfig |   8 +++
> >  drivers/phy/Makefile|   1 +
> >  drivers/phy/phy-ath79-usb.c | 116 
> > 
> >  4 files changed, 133 insertions(+)
> >  create mode 100644 drivers/phy/phy-ath79-usb.c
> > 
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 30aca4a..f536d52 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -1866,6 +1866,14 @@ S:   Maintained
> >  F: drivers/gpio/gpio-ath79.c
> >  F: Documentation/devicetree/bindings/gpio/gpio-ath79.txt
> >  
> > +ATHEROS 71XX/9XXX USB PHY DRIVER
> > +M: Alban Bedel 
> > +W: https://github.com/AlbanBedel/linux
> > +T: git git://github.com/AlbanBedel/linux
> > +S: Maintained
> > +F: drivers/phy/phy-ath79-usb.c
> > +F: Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
> > +
> >  ATHEROS ATH GENERIC UTILITIES
> >  M: "Luis R. Rodriguez" 
> >  L: linux-wirel...@vger.kernel.org
> > diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> > index efbaee4..6090c63 100644
> > --- a/drivers/phy/Kconfig
> > +++ b/drivers/phy/Kconfig
> > @@ -15,6 +15,14 @@ config GENERIC_PHY
> >   phy users can obtain reference to the PHY. All the users of this
> >   framework should select this config.
> >  
> > +config PHY_ATH79_USB
> > +   tristate "Atheros AR71XX/9XXX USB PHY driver"
> > +   depends on ATH79 || COMPILE_TEST
> > +   default y if USB_EHCI_HCD_PLATFORM
> > +   select PHY_SIMPLE
> > +   help
> > + Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
> > +
> >  config PHY_BERLIN_USB
> > tristate "Marvell Berlin USB PHY Driver"
> > depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
> > diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> > index 1cc7268..5c9ca5f 100644
> > --- a/drivers/phy/Makefile
> > +++ b/drivers/phy/Makefile
> > @@ -3,6 +3,7 @@
> >  #
> >  
> >  obj-$(CONFIG_GENERIC_PHY)  += phy-core.o
> > +obj-$(CONFIG_PHY_ATH79_USB)+= phy-ath79-usb.o
> >  obj-$(CONFIG_PHY_BERLIN_USB)   += phy-berlin-usb.o
> >  obj-$(CONFIG_PHY_BERLIN_SATA)  += phy-berlin-sata.o
> >  obj-$(CONFIG_PHY_DM816X_USB)   += phy-dm816x-usb.o
> > diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
> > new file mode 100644
> > index 000..ff49356
> > --- /dev/null
> > +++ b/drivers/phy/phy-ath79-usb.c
> > @@ -0,0 +1,116 @@
> > +/*
> > + * Copyright (C) 2015 Alban Bedel 
> 
> 2016?

I'll fix this one too.

> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + */
> > +
> > +#include 
> > +#include 
> > +#include 
> > +#include 
> > +
> > +struct ath79_usb_phy {
> > +   struct simple_phy sphy;
> > +   struct reset_control *suspend_override;
> > +};
> > +
> > +static int ath79_usb_phy_power_on(struct phy *phy)
> > +{
> > +   struct ath79_usb_phy *priv = container_of(
> > +   phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
> > +   int err;
> > +
> > +   err = simple_phy_power_on(phy);
> 
> Why do you need a separate driver for ath79_usb? We should be able to directly
> use simple phy driver right?

The ath79 PHY controller misuse the reset controller to control a
suspend override. When this reset line is deasserted the PHY is forced
in suspend mode, for normal operations it must be asserted. In short
this extra reset is inverted compared to the normal use of a reset line.

To support that that in the simple driver we would first need to find a
way to support multiple resets. Not impossible, but not trivial either
as we would need to at least get a name list from somewhere. Then we
would need another scheme to indicate that this extra reset need to be
inverted, again possible but it would start be a bit hacky. All in all
that didn't sound like a good idea for something that is supposed to be
a "simple" driver, so a dedicated driver sounded like the best approach
for this case.

Alban

Re: [PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

[Kishon Vijay Abraham I]

Hi,

On Friday 29 January 2016 01:22 AM, Alban Bedel wrote:
> The ATH79 USB phy is very simple, it only have a reset. On some SoC a
> second reset is used to force the phy in suspend mode regardless of the
> USB controller status.
> 
> Signed-off-by: Alban Bedel 
> ---
> Changelog:
> v2: * Rebased on the simple PHY driver
> * Added myself as maintainer of the driver
> ---
>  MAINTAINERS |   8 +++
>  drivers/phy/Kconfig |   8 +++
>  drivers/phy/Makefile|   1 +
>  drivers/phy/phy-ath79-usb.c | 116 
> 
>  4 files changed, 133 insertions(+)
>  create mode 100644 drivers/phy/phy-ath79-usb.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 30aca4a..f536d52 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1866,6 +1866,14 @@ S: Maintained
>  F:   drivers/gpio/gpio-ath79.c
>  F:   Documentation/devicetree/bindings/gpio/gpio-ath79.txt
>  
> +ATHEROS 71XX/9XXX USB PHY DRIVER
> +M:   Alban Bedel 
> +W:   https://github.com/AlbanBedel/linux
> +T:   git git://github.com/AlbanBedel/linux
> +S:   Maintained
> +F:   drivers/phy/phy-ath79-usb.c
> +F:   Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
> +
>  ATHEROS ATH GENERIC UTILITIES
>  M:   "Luis R. Rodriguez" 
>  L:   linux-wirel...@vger.kernel.org
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index efbaee4..6090c63 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -15,6 +15,14 @@ config GENERIC_PHY
> phy users can obtain reference to the PHY. All the users of this
> framework should select this config.
>  
> +config PHY_ATH79_USB
> + tristate "Atheros AR71XX/9XXX USB PHY driver"
> + depends on ATH79 || COMPILE_TEST
> + default y if USB_EHCI_HCD_PLATFORM
> + select PHY_SIMPLE
> + help
> +   Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
> +
>  config PHY_BERLIN_USB
>   tristate "Marvell Berlin USB PHY Driver"
>   depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 1cc7268..5c9ca5f 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -3,6 +3,7 @@
>  #
>  
>  obj-$(CONFIG_GENERIC_PHY)+= phy-core.o
> +obj-$(CONFIG_PHY_ATH79_USB)  += phy-ath79-usb.o
>  obj-$(CONFIG_PHY_BERLIN_USB) += phy-berlin-usb.o
>  obj-$(CONFIG_PHY_BERLIN_SATA)+= phy-berlin-sata.o
>  obj-$(CONFIG_PHY_DM816X_USB) += phy-dm816x-usb.o
> diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
> new file mode 100644
> index 000..ff49356
> --- /dev/null
> +++ b/drivers/phy/phy-ath79-usb.c
> @@ -0,0 +1,116 @@
> +/*
> + * Copyright (C) 2015 Alban Bedel 

2016?
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include 
> +#include 
> +#include 
> +#include 
> +
> +struct ath79_usb_phy {
> + struct simple_phy sphy;
> + struct reset_control *suspend_override;
> +};
> +
> +static int ath79_usb_phy_power_on(struct phy *phy)
> +{
> + struct ath79_usb_phy *priv = container_of(
> + phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
> + int err;
> +
> + err = simple_phy_power_on(phy);

Why do you need a separate driver for ath79_usb? We should be able to directly
use simple phy driver right?

Thanks
Kishon

Re: [PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

[Kishon Vijay Abraham I]

Hi,

On Friday 29 January 2016 01:22 AM, Alban Bedel wrote:
> The ATH79 USB phy is very simple, it only have a reset. On some SoC a
> second reset is used to force the phy in suspend mode regardless of the
> USB controller status.
> 
> Signed-off-by: Alban Bedel 
> ---
> Changelog:
> v2: * Rebased on the simple PHY driver
> * Added myself as maintainer of the driver
> ---
>  MAINTAINERS |   8 +++
>  drivers/phy/Kconfig |   8 +++
>  drivers/phy/Makefile|   1 +
>  drivers/phy/phy-ath79-usb.c | 116 
> 
>  4 files changed, 133 insertions(+)
>  create mode 100644 drivers/phy/phy-ath79-usb.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 30aca4a..f536d52 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1866,6 +1866,14 @@ S: Maintained
>  F:   drivers/gpio/gpio-ath79.c
>  F:   Documentation/devicetree/bindings/gpio/gpio-ath79.txt
>  
> +ATHEROS 71XX/9XXX USB PHY DRIVER
> +M:   Alban Bedel 
> +W:   https://github.com/AlbanBedel/linux
> +T:   git git://github.com/AlbanBedel/linux
> +S:   Maintained
> +F:   drivers/phy/phy-ath79-usb.c
> +F:   Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
> +
>  ATHEROS ATH GENERIC UTILITIES
>  M:   "Luis R. Rodriguez" 
>  L:   linux-wirel...@vger.kernel.org
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index efbaee4..6090c63 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -15,6 +15,14 @@ config GENERIC_PHY
> phy users can obtain reference to the PHY. All the users of this
> framework should select this config.
>  
> +config PHY_ATH79_USB
> + tristate "Atheros AR71XX/9XXX USB PHY driver"
> + depends on ATH79 || COMPILE_TEST
> + default y if USB_EHCI_HCD_PLATFORM
> + select PHY_SIMPLE
> + help
> +   Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
> +
>  config PHY_BERLIN_USB
>   tristate "Marvell Berlin USB PHY Driver"
>   depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 1cc7268..5c9ca5f 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -3,6 +3,7 @@
>  #
>  
>  obj-$(CONFIG_GENERIC_PHY)+= phy-core.o
> +obj-$(CONFIG_PHY_ATH79_USB)  += phy-ath79-usb.o
>  obj-$(CONFIG_PHY_BERLIN_USB) += phy-berlin-usb.o
>  obj-$(CONFIG_PHY_BERLIN_SATA)+= phy-berlin-sata.o
>  obj-$(CONFIG_PHY_DM816X_USB) += phy-dm816x-usb.o
> diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
> new file mode 100644
> index 000..ff49356
> --- /dev/null
> +++ b/drivers/phy/phy-ath79-usb.c
> @@ -0,0 +1,116 @@
> +/*
> + * Copyright (C) 2015 Alban Bedel 

2016?
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include 
> +#include 
> +#include 
> +#include 
> +
> +struct ath79_usb_phy {
> + struct simple_phy sphy;
> + struct reset_control *suspend_override;
> +};
> +
> +static int ath79_usb_phy_power_on(struct phy *phy)
> +{
> + struct ath79_usb_phy *priv = container_of(
> + phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
> + int err;
> +
> + err = simple_phy_power_on(phy);

Why do you need a separate driver for ath79_usb? We should be able to directly
use simple phy driver right?

Thanks
Kishon

[PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

[Alban Bedel]

The ATH79 USB phy is very simple, it only have a reset. On some SoC a
second reset is used to force the phy in suspend mode regardless of the
USB controller status.

Signed-off-by: Alban Bedel 
---
Changelog:
v2: * Rebased on the simple PHY driver
* Added myself as maintainer of the driver
---
 MAINTAINERS |   8 +++
 drivers/phy/Kconfig |   8 +++
 drivers/phy/Makefile|   1 +
 drivers/phy/phy-ath79-usb.c | 116 
 4 files changed, 133 insertions(+)
 create mode 100644 drivers/phy/phy-ath79-usb.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 30aca4a..f536d52 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1866,6 +1866,14 @@ S:   Maintained
 F: drivers/gpio/gpio-ath79.c
 F: Documentation/devicetree/bindings/gpio/gpio-ath79.txt
 
+ATHEROS 71XX/9XXX USB PHY DRIVER
+M: Alban Bedel 
+W: https://github.com/AlbanBedel/linux
+T: git git://github.com/AlbanBedel/linux
+S: Maintained
+F: drivers/phy/phy-ath79-usb.c
+F: Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
+
 ATHEROS ATH GENERIC UTILITIES
 M: "Luis R. Rodriguez" 
 L: linux-wirel...@vger.kernel.org
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index efbaee4..6090c63 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -15,6 +15,14 @@ config GENERIC_PHY
  phy users can obtain reference to the PHY. All the users of this
  framework should select this config.
 
+config PHY_ATH79_USB
+   tristate "Atheros AR71XX/9XXX USB PHY driver"
+   depends on ATH79 || COMPILE_TEST
+   default y if USB_EHCI_HCD_PLATFORM
+   select PHY_SIMPLE
+   help
+ Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
+
 config PHY_BERLIN_USB
tristate "Marvell Berlin USB PHY Driver"
depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 1cc7268..5c9ca5f 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_GENERIC_PHY)  += phy-core.o
+obj-$(CONFIG_PHY_ATH79_USB)+= phy-ath79-usb.o
 obj-$(CONFIG_PHY_BERLIN_USB)   += phy-berlin-usb.o
 obj-$(CONFIG_PHY_BERLIN_SATA)  += phy-berlin-sata.o
 obj-$(CONFIG_PHY_DM816X_USB)   += phy-dm816x-usb.o
diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
new file mode 100644
index 000..ff49356
--- /dev/null
+++ b/drivers/phy/phy-ath79-usb.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2015 Alban Bedel 
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include 
+#include 
+#include 
+#include 
+
+struct ath79_usb_phy {
+   struct simple_phy sphy;
+   struct reset_control *suspend_override;
+};
+
+static int ath79_usb_phy_power_on(struct phy *phy)
+{
+   struct ath79_usb_phy *priv = container_of(
+   phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
+   int err;
+
+   err = simple_phy_power_on(phy);
+   if (err)
+   return err;
+
+   if (priv->suspend_override) {
+   err = reset_control_assert(priv->suspend_override);
+   if (err) {
+   simple_phy_power_off(phy);
+   return err;
+   }
+   }
+
+   return 0;
+}
+
+static int ath79_usb_phy_power_off(struct phy *phy)
+{
+   struct ath79_usb_phy *priv = container_of(
+   phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
+   int err;
+
+   if (priv->suspend_override) {
+   err = reset_control_deassert(priv->suspend_override);
+   if (err)
+   return err;
+   }
+
+   err = simple_phy_power_off(phy);
+   if (err && priv->suspend_override)
+   reset_control_assert(priv->suspend_override);
+
+   return err;
+}
+
+static const struct phy_ops ath79_usb_phy_ops = {
+   .power_on   = ath79_usb_phy_power_on,
+   .power_off  = ath79_usb_phy_power_off,
+   .owner  = THIS_MODULE,
+};
+
+static const struct simple_phy_desc ath79_usb_phy_desc = {
+   .ops = _usb_phy_ops,
+   .reset = "usb-phy",
+   .clk = (void *)-ENOENT,
+};
+
+static int ath79_usb_phy_probe(struct platform_device *pdev)
+{
+   struct ath79_usb_phy *priv;
+   struct phy *phy;
+
+   priv = devm_kzalloc(>dev, sizeof(*priv), GFP_KERNEL);
+   if (!priv)
+   return -ENOMEM;
+
+   priv->suspend_override = devm_reset_control_get_optional(
+   >dev, "usb-suspend-override");
+   if (IS_ERR(priv->suspend_override)) {
+   if (PTR_ERR(priv->suspend_override) == -ENOENT)
+   priv->suspend_override = NULL;
+   else

[PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

[Alban Bedel]

The ATH79 USB phy is very simple, it only have a reset. On some SoC a
second reset is used to force the phy in suspend mode regardless of the
USB controller status.

Signed-off-by: Alban Bedel 
---
Changelog:
v2: * Rebased on the simple PHY driver
* Added myself as maintainer of the driver
---
 MAINTAINERS |   8 +++
 drivers/phy/Kconfig |   8 +++
 drivers/phy/Makefile|   1 +
 drivers/phy/phy-ath79-usb.c | 116 
 4 files changed, 133 insertions(+)
 create mode 100644 drivers/phy/phy-ath79-usb.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 30aca4a..f536d52 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1866,6 +1866,14 @@ S:   Maintained
 F: drivers/gpio/gpio-ath79.c
 F: Documentation/devicetree/bindings/gpio/gpio-ath79.txt
 
+ATHEROS 71XX/9XXX USB PHY DRIVER
+M: Alban Bedel 
+W: https://github.com/AlbanBedel/linux
+T: git git://github.com/AlbanBedel/linux
+S: Maintained
+F: drivers/phy/phy-ath79-usb.c
+F: Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
+
 ATHEROS ATH GENERIC UTILITIES
 M: "Luis R. Rodriguez" 
 L: linux-wirel...@vger.kernel.org
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index efbaee4..6090c63 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -15,6 +15,14 @@ config GENERIC_PHY
  phy users can obtain reference to the PHY. All the users of this
  framework should select this config.
 
+config PHY_ATH79_USB
+   tristate "Atheros AR71XX/9XXX USB PHY driver"
+   depends on ATH79 || COMPILE_TEST
+   default y if USB_EHCI_HCD_PLATFORM
+   select PHY_SIMPLE
+   help
+ Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
+
 config PHY_BERLIN_USB
tristate "Marvell Berlin USB PHY Driver"
depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 1cc7268..5c9ca5f 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_GENERIC_PHY)  += phy-core.o
+obj-$(CONFIG_PHY_ATH79_USB)+= phy-ath79-usb.o
 obj-$(CONFIG_PHY_BERLIN_USB)   += phy-berlin-usb.o
 obj-$(CONFIG_PHY_BERLIN_SATA)  += phy-berlin-sata.o
 obj-$(CONFIG_PHY_DM816X_USB)   += phy-dm816x-usb.o
diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
new file mode 100644
index 000..ff49356
--- /dev/null
+++ b/drivers/phy/phy-ath79-usb.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2015 Alban Bedel 
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include 
+#include 
+#include 
+#include 
+
+struct ath79_usb_phy {
+   struct simple_phy sphy;
+   struct reset_control *suspend_override;
+};
+
+static int ath79_usb_phy_power_on(struct phy *phy)
+{
+   struct ath79_usb_phy *priv = container_of(
+   phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
+   int err;
+
+   err = simple_phy_power_on(phy);
+   if (err)
+   return err;
+
+   if (priv->suspend_override) {
+   err = reset_control_assert(priv->suspend_override);
+   if (err) {
+   simple_phy_power_off(phy);
+   return err;
+   }
+   }
+
+   return 0;
+}
+
+static int ath79_usb_phy_power_off(struct phy *phy)
+{
+   struct ath79_usb_phy *priv = container_of(
+   phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
+   int err;
+
+   if (priv->suspend_override) {
+   err = reset_control_deassert(priv->suspend_override);
+   if (err)
+   return err;
+   }
+
+   err = simple_phy_power_off(phy);
+   if (err && priv->suspend_override)
+   reset_control_assert(priv->suspend_override);
+
+   return err;
+}
+
+static const struct phy_ops ath79_usb_phy_ops = {
+   .power_on   = ath79_usb_phy_power_on,
+   .power_off  = ath79_usb_phy_power_off,
+   .owner  = THIS_MODULE,
+};
+
+static const struct simple_phy_desc ath79_usb_phy_desc = {
+   .ops = _usb_phy_ops,
+   .reset = "usb-phy",
+   .clk = (void *)-ENOENT,
+};
+
+static int ath79_usb_phy_probe(struct platform_device *pdev)
+{
+   struct ath79_usb_phy *priv;
+   struct phy *phy;
+
+   priv = devm_kzalloc(>dev, sizeof(*priv), GFP_KERNEL);
+   if (!priv)
+   return -ENOMEM;
+
+   priv->suspend_override = devm_reset_control_get_optional(
+   >dev, "usb-suspend-override");
+   if (IS_ERR(priv->suspend_override)) {
+   if (PTR_ERR(priv->suspend_override) == -ENOENT)
+