Re: [PATCH v5 23/23] phy: Add support for Qualcomm's USB HS phy

2016-10-23 Thread Peter Chen 
On Fri, Oct 21, 2016 at 12:33:43PM -0700, Stephen Boyd wrote:
> Quoting Peter Chen (2016-10-20 19:20:30)
> > On Thu, Oct 20, 2016 at 04:20:38PM -0700, Stephen Boyd wrote:
> > > Quoting Stephen Boyd (2016-10-17 18:56:36)
> > > > +
> > > > +static int
> > > > +qcom_usb_hs_phy_vbus_notifier(struct notifier_block *nb, unsigned long 
> > > > event,
> > > > + void *ptr)
> > > > +{
> > > > +   struct qcom_usb_hs_phy *uphy;
> > > > +   int is_host;
> > > > +   u8 addr;
> > > > +
> > > > +   uphy = container_of(nb, struct qcom_usb_hs_phy, vbus_notify);
> > > > +   is_host = extcon_get_cable_state_(uphy->id_edev, 
> > > > EXTCON_USB_HOST);
> > > 
> > > Please don't apply this patch. This call now deadlocks on v4.9-rc1
> > > because of how extcon_get_cable_state_() now grabs a lock that is
> > > already held here when we're inside the notifier. It's not really
> > > required that we grab the lock in extcon there, but this has exposed a
> > > flaw in the logic anyway. We don't know if the id pin is going to toggle
> > > before or after this function is called, so we should really keep track
> > > of both vbus and id state in this driver and then do the same ulpi
> > > writes from two different notifiers for both vbus and id pin. We would
> > > be duplicating work sometimes, but that's pretty much the best solution
> > > I can come up with. Otherwise it's racy.
> > > 
> > 
> > Why you need to care id status? If EXTCON_USB event has happened, and
> > event is true, you can set, otherwise, it is clear operation, that's
> > to say you may not need have id extcon phandle, do you think so?
> > 
> 
> I need to add a comment to the code here because I forgot what was going
> on.
> 
> Either way, this code is pulling D+ up when we're in device mode. We
> don't want to do the pullup if we're a host, and vbus extcon only tells
> us if the cable is attached so we can't just rely on that one bit of
> information.
> 
> I suppose that's not really appropriate to do via extcon though in the
> phy driver though, so I'm thinking that it should be rewritten to use
> the phy_set_mode() feature of the phy framework. Basically,
> ci_udc_pullup() will call phy_set_mode() with PHY_MODE_USB_DEVICE or
> PHY_MODE_USB_HOST and then we can set or clear these bits in the ulpi
> register space. I think that will make things simpler here and things
> like soft-connect will work better. Sound good?

I agree with you, and you may notify controller role through
phy_set_mode at the controller probe and role switch routine.

-- 

Best Regards,
Peter Chen
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v5 23/23] phy: Add support for Qualcomm's USB HS phy

2016-10-20 Thread Peter Chen 
On Thu, Oct 20, 2016 at 04:20:38PM -0700, Stephen Boyd wrote:
> Quoting Stephen Boyd (2016-10-17 18:56:36)
> > +
> > +static int
> > +qcom_usb_hs_phy_vbus_notifier(struct notifier_block *nb, unsigned long 
> > event,
> > + void *ptr)
> > +{
> > +   struct qcom_usb_hs_phy *uphy;
> > +   int is_host;
> > +   u8 addr;
> > +
> > +   uphy = container_of(nb, struct qcom_usb_hs_phy, vbus_notify);
> > +   is_host = extcon_get_cable_state_(uphy->id_edev, EXTCON_USB_HOST);
> 
> Please don't apply this patch. This call now deadlocks on v4.9-rc1
> because of how extcon_get_cable_state_() now grabs a lock that is
> already held here when we're inside the notifier. It's not really
> required that we grab the lock in extcon there, but this has exposed a
> flaw in the logic anyway. We don't know if the id pin is going to toggle
> before or after this function is called, so we should really keep track
> of both vbus and id state in this driver and then do the same ulpi
> writes from two different notifiers for both vbus and id pin. We would
> be duplicating work sometimes, but that's pretty much the best solution
> I can come up with. Otherwise it's racy.
> 

Why you need to care id status? If EXTCON_USB event has happened, and
event is true, you can set, otherwise, it is clear operation, that's
to say you may not need have id extcon phandle, do you think so?

-- 

Best Regards,
Peter Chen
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v5 23/23] phy: Add support for Qualcomm's USB HS phy

2016-10-20 Thread Stephen Boyd 
Quoting Stephen Boyd (2016-10-17 18:56:36)
> +
> +static int
> +qcom_usb_hs_phy_vbus_notifier(struct notifier_block *nb, unsigned long event,
> + void *ptr)
> +{
> +   struct qcom_usb_hs_phy *uphy;
> +   int is_host;
> +   u8 addr;
> +
> +   uphy = container_of(nb, struct qcom_usb_hs_phy, vbus_notify);
> +   is_host = extcon_get_cable_state_(uphy->id_edev, EXTCON_USB_HOST);

Please don't apply this patch. This call now deadlocks on v4.9-rc1
because of how extcon_get_cable_state_() now grabs a lock that is
already held here when we're inside the notifier. It's not really
required that we grab the lock in extcon there, but this has exposed a
flaw in the logic anyway. We don't know if the id pin is going to toggle
before or after this function is called, so we should really keep track
of both vbus and id state in this driver and then do the same ulpi
writes from two different notifiers for both vbus and id pin. We would
be duplicating work sometimes, but that's pretty much the best solution
I can come up with. Otherwise it's racy.

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v5 23/23] phy: Add support for Qualcomm's USB HS phy

2016-10-18 Thread Rob Herring 
On Mon, Oct 17, 2016 at 06:56:36PM -0700, Stephen Boyd wrote:
> The high-speed phy on qcom SoCs is controlled via the ULPI
> viewport.
> 
> Cc: Kishon Vijay Abraham I 
> Cc: 
> Cc: Rob Herring 
> Signed-off-by: Stephen Boyd 
> ---
>  .../devicetree/bindings/phy/qcom,usb-hs-phy.txt|  86 +++

Acked-by: Rob Herring 

>  drivers/phy/Kconfig|   8 +
>  drivers/phy/Makefile   |   1 +
>  drivers/phy/phy-qcom-usb-hs.c  | 286 
> +
>  4 files changed, 381 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/qcom,usb-hs-phy.txt
>  create mode 100644 drivers/phy/phy-qcom-usb-hs.c
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v5 23/23] phy: Add support for Qualcomm's USB HS phy

2016-10-18 Thread Rob Herring 
On Mon, Oct 17, 2016 at 06:56:36PM -0700, Stephen Boyd wrote:
> The high-speed phy on qcom SoCs is controlled via the ULPI
> viewport.
> 
> Cc: Kishon Vijay Abraham I 
> Cc: 
> Cc: Rob Herring 
> Signed-off-by: Stephen Boyd 
> ---
>  .../devicetree/bindings/phy/qcom,usb-hs-phy.txt|  86 +++

Acked-by: Rob Herring 

>  drivers/phy/Kconfig|   8 +
>  drivers/phy/Makefile   |   1 +
>  drivers/phy/phy-qcom-usb-hs.c  | 286 
> +
>  4 files changed, 381 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/qcom,usb-hs-phy.txt
>  create mode 100644 drivers/phy/phy-qcom-usb-hs.c
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH v5 23/23] phy: Add support for Qualcomm's USB HS phy

2016-10-17 Thread Stephen Boyd 
The high-speed phy on qcom SoCs is controlled via the ULPI
viewport.

Cc: Kishon Vijay Abraham I 
Cc: 
Cc: Rob Herring 
Signed-off-by: Stephen Boyd 
---
 .../devicetree/bindings/phy/qcom,usb-hs-phy.txt|  86 +++
 drivers/phy/Kconfig|   8 +
 drivers/phy/Makefile   |   1 +
 drivers/phy/phy-qcom-usb-hs.c  | 286 +
 4 files changed, 381 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/qcom,usb-hs-phy.txt
 create mode 100644 drivers/phy/phy-qcom-usb-hs.c

diff --git a/Documentation/devicetree/bindings/phy/qcom,usb-hs-phy.txt 
b/Documentation/devicetree/bindings/phy/qcom,usb-hs-phy.txt
new file mode 100644
index ..ed994dbc9248
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/qcom,usb-hs-phy.txt
@@ -0,0 +1,86 @@
+Qualcomm's USB HS PHY
+
+PROPERTIES
+
+- compatible:
+Usage: required
+Value type: 
+Definition: Should contain "qcom,usb-hs-phy" and more specifically one of 
the
+following:
+
+"qcom,usb-hs-phy-apq8064"
+"qcom,usb-hs-phy-msm8916"
+"qcom,usb-hs-phy-msm8974"
+
+- #phy-cells:
+Usage: required
+Value type: 
+Definition: Should contain 0
+
+- clocks:
+Usage: required
+Value type: 
+Definition: Should contain clock specifier for the reference and sleep
+clocks
+
+- clock-names:
+Usage: required
+Value type: 
+Definition: Should contain "ref" and "sleep" for the reference and sleep
+clocks respectively
+
+- resets:
+Usage: required
+Value type: 
+Definition: Should contain the phy and POR resets
+
+- reset-names:
+Usage: required
+Value type: 
+Definition: Should contain "phy" and "por" for the phy and POR resets
+respectively
+
+- v3p3-supply:
+Usage: required
+Value type: 
+Definition: Should contain a reference to the 3.3V supply
+
+- v1p8-supply:
+Usage: required
+Value type: 
+Definition: Should contain a reference to the 1.8V supply
+
+- extcon:
+Usage: optional
+Value type: 
+Definition: Should contain the vbus and ID extcons in the first and second
+cells respectively
+
+- qcom,init-seq:
+Usage: optional
+Value type: 
+Definition: Should contain a sequence of ULPI address and value pairs to
+program into the ULPI_EXT_VENDOR_SPECIFIC area. This is related
+to Device Mode Eye Diagram test. The addresses are offsets
+   from the ULPI_EXT_VENDOR_SPECIFIC address, for example,
+   <0x1 0x53> would mean we should write the value 0x53 to address
+   0x81.
+
+EXAMPLE
+
+otg: usb-controller {
+   ulpi {
+   phy {
+   compatible = "qcom,usb-hs-phy-msm8974", 
"qcom,usb-hs-phy";
+   #phy-cells = <0>;
+   clocks = <_board>, < GCC_USB2A_PHY_SLEEP_CLK>;
+   clock-names = "ref", "sleep";
+   resets = < GCC_USB2A_PHY_BCR>, < 0>;
+   reset-names = "phy", "por";
+   v3p3-supply = <_l24>;
+   v1p8-supply = <_l6>;
+   extcon = <>, <_id>;
+   qcom,init-seq = /bits/ 8 <0x1 0x63>;
+   };
+   };
+};
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 6bfc91a8ea3e..3fcfc5899b6d 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -453,6 +453,14 @@ config PHY_QCOM_UFS
help
  Support for UFS PHY on QCOM chipsets.
 
+config PHY_QCOM_USB_HS
+   tristate "Qualcomm USB HS PHY module"
+   depends on USB_ULPI_BUS
+   select GENERIC_PHY
+   help
+ Support for the USB high-speed ULPI compliant phy on Qualcomm
+ chipsets.
+
 config PHY_QCOM_USB_HSIC
tristate "Qualcomm USB HSIC ULPI PHY module"
depends on USB_ULPI_BUS
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 914b843eac13..df62074ded2f 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -54,6 +54,7 @@ obj-$(CONFIG_PHY_STIH41X_USB) += phy-stih41x-usb.o
 obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs.o
 obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs-qmp-20nm.o
 obj-$(CONFIG_PHY_QCOM_UFS) += phy-qcom-ufs-qmp-14nm.o
+obj-$(CONFIG_PHY_QCOM_USB_HS)  += phy-qcom-usb-hs.o
 obj-$(CONFIG_PHY_QCOM_USB_HSIC)+= phy-qcom-usb-hsic.o
 obj-$(CONFIG_PHY_TUSB1210) += phy-tusb1210.o
 obj-$(CONFIG_PHY_BRCM_SATA)+= phy-brcm-sata.o
diff --git a/drivers/phy/phy-qcom-usb-hs.c b/drivers/phy/phy-qcom-usb-hs.c
new file mode 100644
index ..00cc86e94749
--- /dev/null
+++ b/drivers/phy/phy-qcom-usb-hs.c
@@ -0,0 +1,286 @@
+/**
+ * Copyright (C) 2016