Puneet,
-----Original Message----- From: Puneet Saxena Sent: Thursday, February 23, 2012 7:25 AM To: u-boot@lists.denx.de; sjg@chromium.org Cc: vapier@gentoo.org; Tom Warren; Puneet Saxena Subject: [PATCH 2/2] usb: Add quirk "USB_QUIRK_STRING_FETCH_255"
Add a quirk "USB_QUIRK_STRING_FETCH_255", borrowed from Linux kernel to fetch string using descriptor length then fetch actual bytes returned in descriptor buffer.
Signed-off-by: Puneet Saxena puneets@nvidia.com
Changes for v2:
- Add quirk for fetching actual bytes
common/usb.c | 4 ++++ include/configs/tegra2-common.h | 7 +++++++ 2 files changed, 11 insertions(+), 0 deletions(-)
diff --git a/common/usb.c b/common/usb.c index 75926aa..cd85c18 100644 --- a/common/usb.c +++ b/common/usb.c @@ -660,7 +660,11 @@ static int usb_string_sub(struct usb_device *dev, unsigned int langid,
/* Try to read the string descriptor by asking for the maximum * possible number of bytes */ +#ifdef USB_QUIRK_STRING_FETCH_255
- rc = -4;
+#else rc = usb_get_string(dev, langid, index, buf, 255); +#endif
/* If that failed try to read the descriptor length, then * ask for just that many bytes */ diff --git a/include/configs/tegra2-common.h b/include/configs/tegra2- common.h index 266d0e5..51cc200 100644 --- a/include/configs/tegra2-common.h +++ b/include/configs/tegra2-common.h @@ -172,4 +172,11 @@
#define CONFIG_TEGRA2_GPIO #define CONFIG_CMD_GPIO
+/*
- Imported the quirk from Linux kernel */
+/* string descriptors must not be fetched using a 255-byte read */ +#define USB_QUIRK_STRING_FETCH_255 0x00000001
#endif /* __TEGRA2_COMMON_H */
1.7.1
Make sure you include the USB custodian/expert when submitting USB patches (Remy Bohmer, linux@bohmer.net). Also, as TomR says, this should be a CONFIG_USB_QUIRK_xxx string. Note that it doesn't need a 0x00000001 - #define'ing a switch means it's explicitly enabled - no need for 1 or 0 (see all the other CONFIG_ defines in the config headers).
Tom