Introduce otg_version field in usb_gadget struct. UDC can
advertise OTG spec version compatibility by setting otg_version
field appropriately. Gadget drivers fill the bcdOTG field in
OTG descriptor based on UDC's OTG version.
Add sysfs file for host_request and UDC returns the same when
HNP polling request arrives from the host.
Signed-off-by: Pavankumar Kondeti <pkondeti@xxxxxxxxxxxxxx>
---
This patch only modifies gadget zero. But the final patch will
modify all the gadget drivers.
.../testing/sysfs-devices-platform-_UDC_-gadget | 14 ++++++++++++
drivers/usb/gadget/composite.c | 23 ++++++++++++++++++++
drivers/usb/gadget/zero.c | 3 ++
include/linux/usb/gadget.h | 21 ++++++++++++++++++
4 files changed, 61 insertions(+), 0 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-devices-platform-_UDC_-gadget b/Documentation/ABI/testing/sysfs-devices-platform-_UDC_-gadget
index d548eaa..9c622e4 100644
--- a/Documentation/ABI/testing/sysfs-devices-platform-_UDC_-gadget
+++ b/Documentation/ABI/testing/sysfs-devices-platform-_UDC_-gadget
@@ -19,3 +19,17 @@ Description:
Possible values are:
1 -> ignore the FUA flag
0 -> obey the FUA flag
+
+What: /sys/devices/platform/_UDC_/gadget/host_request
+Date: December 2010
+Contact: Pavan Kondeti <pkondeti@xxxxxxxxxxxxxx>
+Description:
+ OTG 2.0 compliant host keeps polling OTG2.0 peripheral
+ for host role. Set host_request flag, which tells host
+ to give up the host role to peripheral.
+
+ 1 -> host role is requested
+ 0 -> no effect (automatically cleared upon reset/disconnect)
+
+ (_UDC_ is the name of the USB Device Controller driver)
+
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 77cabcb..f3a2023 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -978,6 +978,7 @@ static void composite_disconnect(struct usb_gadget *gadget)
struct usb_composite_dev *cdev = get_gadget_data(gadget);
unsigned long flags;
+ gadget->host_request = 0;
/* REVISIT: should we have config and device level
* disconnect callbacks?
*/
@@ -1003,6 +1004,23 @@ static ssize_t composite_show_suspended(struct device *dev,
static DEVICE_ATTR(suspended, 0444, composite_show_suspended, NULL);
+static ssize_t composite_set_host_request(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct usb_gadget *gadget = dev_to_usb_gadget(dev);
+ int value;
+
+ if (sscanf(buf, "%d", &value) != 1)
+ return -EINVAL;
+
+ gadget->host_request = !!value;
+ return count;
+
+}
+
+static DEVICE_ATTR(host_request, S_IWUSR, NULL, composite_set_host_request);
+
static void
composite_unbind(struct usb_gadget *gadget)
{
@@ -1047,6 +1065,7 @@ composite_unbind(struct usb_gadget *gadget)
kfree(cdev->req->buf);
usb_ep_free_request(gadget->ep0, cdev->req);
}
+ device_remove_file(&gadget->dev, &dev_attr_host_request);
device_remove_file(&gadget->dev, &dev_attr_suspended);
kfree(cdev);
set_gadget_data(gadget, NULL);
@@ -1158,6 +1177,10 @@ static int composite_bind(struct usb_gadget *gadget)
if (status)
goto fail;
+ status = device_create_file(&gadget->dev, &dev_attr_host_request);
+ if (status)
+ DBG(cdev, "unable to create host_request sysfs file\n");
+
INFO(cdev, "%s ready\n", composite->name);
return 0;
diff --git a/drivers/usb/gadget/zero.c b/drivers/usb/gadget/zero.c
index 6d16db9..b4fb719 100644
--- a/drivers/usb/gadget/zero.c
+++ b/drivers/usb/gadget/zero.c
@@ -293,6 +293,9 @@ static int __init zero_bind(struct usb_composite_dev *cdev)
setup_timer(&autoresume_timer, zero_autoresume, (unsigned long) cdev);
+ if (gadget_is_otg2(cdev->gadget))
+ otg_descriptor.bcdOTG = __constant_cpu_to_le16(0x0200);
+
/* Register primary, then secondary configuration. Note that
* SH3 only allows one config...
*/
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 006412c..b891257 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -443,6 +443,8 @@ struct usb_gadget_ops {
* operation. If it does, the gadget driver must also support both.
* @is_otg: True if the USB device port uses a Mini-AB jack, so that the
* gadget driver must provide a USB OTG descriptor.
+ * @otg_version: UDC OTG version based on which gadget driver fills the
+ * bcdOTG field in a USB OTG descriptor.
* @is_a_peripheral: False unless is_otg, the "A" end of a USB cable
* is in the Mini-AB jack, and HNP has been used to switch roles
* so that the "A" device currently acts as A-Peripheral, not A-Host.
@@ -452,6 +454,7 @@ struct usb_gadget_ops {
* only supports HNP on a different root port.
* @b_hnp_enable: OTG device feature flag, indicating that the A-Host
* enabled HNP support.
+ * @host_request: A Flag, indicating that user wishes to take the host role.
* @name: Identifies the controller hardware type. Used in diagnostics
* and sometimes configuration.
* @dev: Driver model state for this abstract device.
@@ -482,10 +485,14 @@ struct usb_gadget {
enum usb_device_speed speed;
unsigned is_dualspeed:1;
unsigned is_otg:1;
+ u16 otg_version;
+#define UDC_OTG1 0x0000
+#define UDC_OTG2 0x0001
unsigned is_a_peripheral:1;
unsigned b_hnp_enable:1;
unsigned a_hnp_support:1;
unsigned a_alt_hnp_support:1;
+ unsigned host_request:1;
const char *name;
struct device dev;
};
@@ -537,6 +544,20 @@ static inline int gadget_is_otg(struct usb_gadget *g)
}
/**
+ * gadget_is_otg2 - return true if UDC is compliant to OTG 2.0
+ * @g: controller that might have a Mini-AB/Micro-AB connector
+ *
+ */
+static inline int gadget_is_otg2(struct usb_gadget *g)
+{
+#ifdef CONFIG_USB_OTG
+ return g->otg_version && UDC_OTG2;
+#else
+ return 0;
+#endif
+}
+
+/**
* usb_gadget_frame_number - returns the current frame number
* @gadget: controller that reports the frame number
*
--
1.7.1
--
Sent by a consultant of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
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