Since a_alt_hnp_support is obsolete in OTG 2.0, HNP capable host should
send this set feature request only if the otg device is connecting to a
non-HNP port and it's compliant with OTG 1.x revision. This is done by
checking its otg descriptor length, OTG 2.0 uses usb_otg20_descriptor
which has different length than OTG 1.x using usb_otg_descriptor.
Signed-off-by: Li Jun <jun.li@xxxxxxxxxxxxx>
---
Changes for v2:
- Change dev_info to be dev_err if set otg features failed.
- Coding style update for line charactors less than 80.
drivers/usb/core/hub.c | 68 +++++++++++++++++++++++++++---------------------
1 file changed, 39 insertions(+), 29 deletions(-)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 431839b..609db97 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2240,39 +2240,49 @@ static int usb_enumerate_device_otg(struct usb_device *udev)
&& udev->parent == udev->bus->root_hub) {
struct usb_otg_descriptor *desc = NULL;
struct usb_bus *bus = udev->bus;
+ unsigned port1 = udev->portnum;
/* descriptor may appear anywhere in config */
- if (__usb_get_extra_descriptor(udev->rawdescriptors[0],
- le16_to_cpu(udev->config[0].desc.wTotalLength),
- USB_DT_OTG, (void **) &desc) == 0) {
- if (desc->bmAttributes & USB_OTG_HNP) {
- unsigned port1 = udev->portnum;
+ err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
+ le16_to_cpu(udev->config[0].desc.wTotalLength),
+ USB_DT_OTG, (void **) &desc);
+ if (err || !(desc->bmAttributes & USB_OTG_HNP))
+ return 0;
- dev_info(&udev->dev,
- "Dual-Role OTG device on %sHNP port\n",
- (port1 == bus->otg_port)
- ? "" : "non-");
-
- /* enable HNP before suspend, it's simpler */
- if (port1 == bus->otg_port)
- bus->b_hnp_enable = 1;
- err = usb_control_msg(udev,
- usb_sndctrlpipe(udev, 0),
- USB_REQ_SET_FEATURE, 0,
- bus->b_hnp_enable
- ? USB_DEVICE_B_HNP_ENABLE
- : USB_DEVICE_A_ALT_HNP_SUPPORT,
- 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
- if (err < 0) {
- /* OTG MESSAGE: report errors here,
- * customize to match your product.
- */
- dev_info(&udev->dev,
- "can't set HNP mode: %d\n",
- err);
- bus->b_hnp_enable = 0;
- }
+ dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
+ (port1 == bus->otg_port) ? "" : "non-");
+
+ /* enable HNP before suspend, it's simpler */
+ if (port1 == bus->otg_port) {
+ bus->b_hnp_enable = 1;
+ err = usb_control_msg(udev,
+ usb_sndctrlpipe(udev, 0),
+ USB_REQ_SET_FEATURE, 0,
+ USB_DEVICE_B_HNP_ENABLE,
+ 0, NULL, 0,
+ USB_CTRL_SET_TIMEOUT);
+ if (err < 0) {
+ /*
+ * OTG MESSAGE: report errors here,
+ * customize to match your product.
+ */
+ dev_err(&udev->dev, "can't set HNP mode: %d\n",
+ err);
+ bus->b_hnp_enable = 0;
}
+ } else if (desc->bLength == sizeof
+ (struct usb_otg_descriptor)) {
+ /* Set a_alt_hnp_support for legacy otg device */
+ err = usb_control_msg(udev,
+ usb_sndctrlpipe(udev, 0),
+ USB_REQ_SET_FEATURE, 0,
+ USB_DEVICE_A_ALT_HNP_SUPPORT,
+ 0, NULL, 0,
+ USB_CTRL_SET_TIMEOUT);
+ if (err < 0)
+ dev_err(&udev->dev,
+ "set a_alt_hnp_support failed: %d\n",
+ err);
}
}
#endif
--
1.7.9.5
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