diff mbox

[v2] usb: chipidea: Use extcon framework for VBUS and ID detect

Message ID 1429104915-11079-1-git-send-email-ivan.ivanov@linaro.org
State New
Headers show

Commit Message

Ivan T. Ivanov April 15, 2015, 1:35 p.m. UTC 
On recent Qualcomm platforms VBUS and ID lines are not routed to
USB PHY LINK controller. Use extcon framework to receive connect
and disconnect ID and VBUS notification.

Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
---

Changes since v0 [1], as per Peter Chen suggestions:

* Moved external connector parsing code to ci_get_platdata()
* Moved external connector related variables to struct ci_hdrc_platform_data
* Rename ci_host_notifier() to ci_id_notifier()
* Fixed device bindings description
* Use select EXTCON framework, instead of depends on.

[1] https://lkml.org/lkml/2015/4/9/116

 .../devicetree/bindings/usb/ci-hdrc-qcom.txt       |  9 +++
 drivers/usb/chipidea/Kconfig                       |  1 +
 drivers/usb/chipidea/core.c                        | 87 ++++++++++++++++++++++
 drivers/usb/chipidea/otg.c                         | 26 ++++++-
 include/linux/usb/chipidea.h                       | 17 +++++
 5 files changed, 139 insertions(+), 1 deletion(-)

--
1.9.1

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Comments

Ivan T. Ivanov April 15, 2015, 2:54 p.m. UTC | #1 
Hi Robert,

On Wed, 2015-04-15 at 16:11 +0200, Robert Baldyga wrote:
> Hi Ivan,
> 
> On 04/15/2015 03:35 PM, Ivan T. Ivanov wrote:
> > On recent Qualcomm platforms VBUS and ID lines are not routed to
> > USB PHY LINK controller. Use extcon framework to receive connect
> > and disconnect ID and VBUS notification.
> > 
> > Signed-off-by: Ivan T. Ivanov ivanov@linaro.org>
> > ---
> > 
> > Changes since v0 [1], as per Peter Chen suggestions:
> > 
> > * Moved external connector parsing code to ci_get_platdata()
> > * Moved external connector related variables to struct ci_hdrc_platform_data
> > * Rename ci_host_notifier() to ci_id_notifier()
> > * Fixed device bindings description
> > * Use select EXTCON framework, instead of depends on.
> > 
> > [1] https://lkml.org/lkml/2015/4/9/116
> > 
> >  .../devicetree/bindings/usb/ci-hdrc-qcom.txt       |  9 +++
> >  drivers/usb/chipidea/Kconfig                       |  1 +
> >  drivers/usb/chipidea/core.c                        | 87 ++++++++++++++++++++++
> >  drivers/usb/chipidea/otg.c                         | 26 ++++++-
> >  include/linux/usb/chipidea.h                       | 17 +++++
> >  5 files changed, 139 insertions(+), 1 deletion(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt 
> > b/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt
> > index f2899b5..c635aca 100644
> > --- a/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt
> > +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt
> > @@ -7,6 +7,14 @@ Required properties:
> >  - usb-phy:      phandle for the PHY device
> >  - dr_mode:      Should be "peripheral"
> > 
> > +Optional properties:
> > +- extcon:       phandles to external connector devices. First phandle
> > +                should point to external connector, which provide "USB"
> > +                cable events, the second should point to external connector
> > +                device, which provide "USB-HOST" cable events. If one of
> > +                the external connector devices is not required, empty <0>
> > +                phandle should be specified.
> 
> Do you expect to have "USB" and "USB-HOST" notifiers supplied by two
> different extcon drivers? It looks strange. I don't think so that we
> ever will need to deal with such weird configuration.

Yes. That is what I have today on my desk.

> 
> > +
> >  Examples:
> >        gadget@f9a55000 {
> >                 compatible = "qcom,ci-hdrc";
> > @@ -14,4 +22,5 @@ Examples:
> >                 dr_mode = "peripheral";
> >                 interrupts = <0 134 0>;
> >                 usb-phy = <&usbphy0>;
> > +               extcon = <0>, <&usb_id>;
> >         };
> > diff --git a/drivers/usb/chipidea/Kconfig b/drivers/usb/chipidea/Kconfig
> > index 5ce3f1d..5619b8c 100644
> > --- a/drivers/usb/chipidea/Kconfig
> > +++ b/drivers/usb/chipidea/Kconfig
> > @@ -1,6 +1,7 @@
> >  config USB_CHIPIDEA
> >         tristate "ChipIdea Highspeed Dual Role Controller"
> >         depends on ((USB_EHCI_HCD && USB_GADGET) || (USB_EHCI_HCD && !USB_GADGET) || 
> > (!USB_EHCI_HCD && USB_GADGET)) && HAS_DMA
> > +       select EXTCON
> >         help
> >                         Say Y here if your system has a dual role high speed USB
> >                         controller based on ChipIdea silicon IP. Currently, only the
> > diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
> > index 74fea4f..e1d495d 100644
> > --- a/drivers/usb/chipidea/core.c
> > +++ b/drivers/usb/chipidea/core.c
> > @@ -47,6 +47,7 @@
> >  #include <linux/delay.h>
> >  #include <linux/device.h>
> >  #include <linux/dma-mapping.h>
> > +#include <linux/extcon.h>
> >  #include <linux/phy/phy.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/module.h>
> > @@ -557,9 +558,39 @@ static irqreturn_t ci_irq(int irq, void *data)
> >         return ret;
> >  }
> > 
> > +static int ci_vbus_notifier(struct notifier_block *nb, unsigned long event,
> > +                               void *ptr)
> > +{
> > +       struct ci_hdrc_cable *vbus = container_of(nb, struct ci_hdrc_cable, nb);
> > +
> > +       if (event)
> > +               vbus->state = true;
> > +       else
> > +               vbus->state = false;
> > +
> > +       return NOTIFY_DONE;
> > +}
> 
> Actually it's not true that "USB" cable state is equal to VBUS state.

But this is how it supposed to work right now, no?

I have to admit that the naming is really confusing.

> "USB" and "USB-HOST" are mutually exclusive, and when you have ID=0,
> which means "USB-HOST" is connected, "USB cable will be seen as
> disconnected even when VBUS=1.
> 
> We are currently discussing how to pass VBUS state to USB OTG drivers.
> You can find discussion here:
> http://www.spinics.net/lists/linux-usb/msg123895.html

Sure, I am following this discussion. When it settles down, I can change
this as appropriate, until then this is what we will have in 4.1.

It will be messy refactoring, I think. All extcon providers and consumers
are using strings to denote cable names. Not to mention that extcon-class
is using "USB-Host", while all others are using "USB-HOST".

Regards,
Ivan

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Ivan T. Ivanov May 26, 2015, 7:47 a.m. UTC | #2 
On Wed, 2015-04-15 at 16:35 +0300, Ivan T. Ivanov wrote:
> On recent Qualcomm platforms VBUS and ID lines are not routed to
> USB PHY LINK controller. Use extcon framework to receive connect
> and disconnect ID and VBUS notification.
> 
> Signed-off-by: Ivan T. Ivanov ivanov@linaro.org>
> ---
> 
> Changes since v0 [1], as per Peter Chen suggestions:
> 
> * Moved external connector parsing code to ci_get_platdata()
> * Moved external connector related variables to struct ci_hdrc_platform_data
> * Rename ci_host_notifier() to ci_id_notifier()
> * Fixed device bindings description
> * Use select EXTCON framework, instead of depends on.
> 
> [1] https://lkml.org/lkml/2015/4/9/116

Hi Peter, 

Did you have any further comments on this patch
or what is your plan about it.

Regards,
Ivan
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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt
index f2899b5..c635aca 100644
--- a/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt
+++ b/Documentation/devicetree/bindings/usb/ci-hdrc-qcom.txt
@@ -7,6 +7,14 @@  Required properties:
 - usb-phy:      phandle for the PHY device
 - dr_mode:      Should be "peripheral"

+Optional properties:
+- extcon:       phandles to external connector devices. First phandle
+                should point to external connector, which provide "USB"
+                cable events, the second should point to external connector
+                device, which provide "USB-HOST" cable events. If one of
+                the external connector devices is not required, empty <0>
+                phandle should be specified.
+
 Examples:
 	gadget@f9a55000 {
 		compatible = "qcom,ci-hdrc";
@@ -14,4 +22,5 @@  Examples:
 		dr_mode = "peripheral";
 		interrupts = <0 134 0>;
 		usb-phy = <&usbphy0>;
+		extcon = <0>, <&usb_id>;
 	};
diff --git a/drivers/usb/chipidea/Kconfig b/drivers/usb/chipidea/Kconfig
index 5ce3f1d..5619b8c 100644
--- a/drivers/usb/chipidea/Kconfig
+++ b/drivers/usb/chipidea/Kconfig
@@ -1,6 +1,7 @@ 
 config USB_CHIPIDEA
 	tristate "ChipIdea Highspeed Dual Role Controller"
 	depends on ((USB_EHCI_HCD && USB_GADGET) || (USB_EHCI_HCD && !USB_GADGET) || (!USB_EHCI_HCD && USB_GADGET)) && HAS_DMA
+	select EXTCON
 	help
 	  Say Y here if your system has a dual role high speed USB
 	  controller based on ChipIdea silicon IP. Currently, only the
diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index 74fea4f..e1d495d 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -47,6 +47,7 @@ 
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
+#include <linux/extcon.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/module.h>
@@ -557,9 +558,39 @@  static irqreturn_t ci_irq(int irq, void *data)
 	return ret;
 }

+static int ci_vbus_notifier(struct notifier_block *nb, unsigned long event,
+			 void *ptr)
+{
+	struct ci_hdrc_cable *vbus = container_of(nb, struct ci_hdrc_cable, nb);
+
+	if (event)
+		vbus->state = true;
+	else
+		vbus->state = false;
+
+	return NOTIFY_DONE;
+}
+
+static int ci_id_notifier(struct notifier_block *nb, unsigned long event,
+		       void *ptr)
+{
+	struct ci_hdrc_cable *id = container_of(nb, struct ci_hdrc_cable, nb);
+
+	if (event)
+		id->state = false;
+	else
+		id->state = true;
+
+	return NOTIFY_DONE;
+}
+
 static int ci_get_platdata(struct device *dev,
 		struct ci_hdrc_platform_data *platdata)
 {
+	struct extcon_dev *ext_vbus, *ext_id;
+	struct ci_hdrc_cable *cable;
+	int ret;
+
 	if (!platdata->phy_mode)
 		platdata->phy_mode = of_usb_get_phy_mode(dev->of_node);

@@ -591,6 +622,53 @@  static int ci_get_platdata(struct device *dev,
 	if (of_usb_get_maximum_speed(dev->of_node) == USB_SPEED_FULL)
 		platdata->flags |= CI_HDRC_FORCE_FULLSPEED;

+	ext_id = ERR_PTR(-ENODEV);
+	ext_vbus = ERR_PTR(-ENODEV);
+	if (of_property_read_bool(dev->of_node, "extcon")) {
+		/* Each one of them is not mandatory */
+		ext_vbus = extcon_get_edev_by_phandle(dev, 0);
+		if (IS_ERR(ext_vbus) && PTR_ERR(ext_vbus) != -ENODEV)
+			return PTR_ERR(ext_vbus);
+
+		ext_id = extcon_get_edev_by_phandle(dev, 1);
+		if (IS_ERR(ext_id) && PTR_ERR(ext_id) != -ENODEV)
+			return PTR_ERR(ext_id);
+	}
+
+	if (!IS_ERR(ext_vbus)) {
+		cable = &platdata->vbus_extcon;
+		cable->nb.notifier_call = ci_vbus_notifier;
+		ret = extcon_register_interest(&cable->conn, ext_vbus->name,
+					       "USB", &cable->nb);
+		if (ret < 0) {
+			dev_err(dev, "register VBUS failed\n");
+			return ret;
+		}
+
+		ret = extcon_get_cable_state(ext_vbus, "USB");
+		if (ret)
+			cable->state = true;
+		else
+			cable->state = false;
+	}
+
+	if (!IS_ERR(ext_id)) {
+		cable = &platdata->id_extcon;
+		cable->nb.notifier_call = ci_id_notifier;
+		ret = extcon_register_interest(&cable->conn, ext_id->name,
+					       "USB-HOST", &cable->nb);
+		if (ret < 0) {
+			dev_err(dev, "register ID failed\n");
+			return ret;
+		}
+
+		ret = extcon_get_cable_state(ext_id, "USB-HOST");
+		if (ret)
+			cable->state = false;
+		else
+			cable->state = true;
+	}
+
 	return 0;
 }

@@ -845,6 +923,7 @@  deinit_phy:
 static int ci_hdrc_remove(struct platform_device *pdev)
 {
 	struct ci_hdrc *ci = platform_get_drvdata(pdev);
+	struct extcon_specific_cable_nb *cable_nb;

 	if (ci->supports_runtime_pm) {
 		pm_runtime_get_sync(&pdev->dev);
@@ -852,6 +931,14 @@  static int ci_hdrc_remove(struct platform_device *pdev)
 		pm_runtime_put_noidle(&pdev->dev);
 	}

+	cable_nb = &ci->platdata->id_extcon.conn;
+	if (cable_nb->edev)
+		extcon_unregister_interest(cable_nb);
+
+	cable_nb = &ci->platdata->vbus_extcon.conn;
+	if (cable_nb->edev)
+		extcon_unregister_interest(cable_nb);
+
 	dbg_remove_files(ci);
 	ci_role_destroy(ci);
 	ci_hdrc_enter_lpm(ci, true);
diff --git a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c
index ad6c87a..34dd196 100644
--- a/drivers/usb/chipidea/otg.c
+++ b/drivers/usb/chipidea/otg.c
@@ -30,7 +30,31 @@ 
  */
 u32 hw_read_otgsc(struct ci_hdrc *ci, u32 mask)
 {
-	return hw_read(ci, OP_OTGSC, mask);
+	struct ci_hdrc_cable *cable;
+	u32 val = hw_read(ci, OP_OTGSC, mask);
+
+	/*
+	 * If using extcon framework for VBUS and/or ID signal
+	 * detection overwrite OTGSC resiter value
+	 */
+	cable = &ci->platdata->vbus_extcon;
+	if ((mask & OTGSC_BSV) && cable->conn.edev) {
+		if (cable->state)
+			val |= OTGSC_BSV;
+		else
+			val &= ~OTGSC_BSV;
+	}
+
+	cable = &ci->platdata->id_extcon;
+	if ((mask & OTGSC_ID) && cable->conn.edev) {
+		if (cable->state)
+			val |= OTGSC_ID;
+		else
+			val &= ~OTGSC_ID;
+	}
+
+	val &= mask;
+	return val;
 }

 /**
diff --git a/include/linux/usb/chipidea.h b/include/linux/usb/chipidea.h
index ab94f78..0eedaf6 100644
--- a/include/linux/usb/chipidea.h
+++ b/include/linux/usb/chipidea.h
@@ -5,8 +5,21 @@ 
 #ifndef __LINUX_USB_CHIPIDEA_H
 #define __LINUX_USB_CHIPIDEA_H

+#include <linux/extcon.h>
 #include <linux/usb/otg.h>

+/**
+ * struct ci_hdrc_cable - structure for external connector cable state tracking
+ * @state: current state of the line
+ * @nb: hold event notification callback
+ * @conn: used for notification registration
+ */
+struct ci_hdrc_cable {
+	bool				state;
+	struct notifier_block		nb;
+	struct extcon_specific_cable_nb conn;
+};
+
 struct ci_hdrc;
 struct ci_hdrc_platform_data {
 	const char	*name;
@@ -35,6 +48,10 @@  struct ci_hdrc_platform_data {
 	void	(*notify_event) (struct ci_hdrc *ci, unsigned event);
 	struct regulator	*reg_vbus;
 	bool			tpl_support;
+
+	/* VBUS and ID signal state tracking, using extcon framework */
+	struct ci_hdrc_cable		vbus_extcon;
+	struct ci_hdrc_cable		id_extcon;
 };

 /* Default offset of capability registers */