From 3de6e63f7845e99981e489ddccf70b3ec02fe00a Mon Sep 17 00:00:00 2001 From: Bhupesh Sharma Date: Fri, 1 Jun 2012 15:08:54 +0530 Subject: [PATCH] usb: gadget: uvc: Fix string descriptor STALL issue when multiple uvc functions are added to a configuration This patch solved the string descriptor STALL issue when we add multiple UVC functions in a single configuration using a 'webcam.c' like composite driver. Signed-off-by: Bhupesh Sharma Signed-off-by: Felipe Balbi --- drivers/usb/gadget/f_uvc.c | 38 ++++++++++++++++++++++---------------- 1 file changed, 22 insertions(+), 16 deletions(-) diff --git a/drivers/usb/gadget/f_uvc.c b/drivers/usb/gadget/f_uvc.c index 2022fe49..054c35a 100644 --- a/drivers/usb/gadget/f_uvc.c +++ b/drivers/usb/gadget/f_uvc.c @@ -619,22 +619,28 @@ uvc_bind_config(struct usb_configuration *c, uvc->desc.fs_streaming = fs_streaming; uvc->desc.hs_streaming = hs_streaming; - /* Allocate string descriptor numbers. */ - if ((ret = usb_string_id(c->cdev)) < 0) - goto error; - uvc_en_us_strings[UVC_STRING_ASSOCIATION_IDX].id = ret; - uvc_iad.iFunction = ret; - - if ((ret = usb_string_id(c->cdev)) < 0) - goto error; - uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id = ret; - uvc_control_intf.iInterface = ret; - - if ((ret = usb_string_id(c->cdev)) < 0) - goto error; - uvc_en_us_strings[UVC_STRING_STREAMING_IDX].id = ret; - uvc_streaming_intf_alt0.iInterface = ret; - uvc_streaming_intf_alt1.iInterface = ret; + /* maybe allocate device-global string IDs, and patch descriptors */ + if (uvc_en_us_strings[UVC_STRING_ASSOCIATION_IDX].id == 0) { + /* Allocate string descriptor numbers. */ + ret = usb_string_id(c->cdev); + if (ret < 0) + goto error; + uvc_en_us_strings[UVC_STRING_ASSOCIATION_IDX].id = ret; + uvc_iad.iFunction = ret; + + ret = usb_string_id(c->cdev); + if (ret < 0) + goto error; + uvc_en_us_strings[UVC_STRING_CONTROL_IDX].id = ret; + uvc_control_intf.iInterface = ret; + + ret = usb_string_id(c->cdev); + if (ret < 0) + goto error; + uvc_en_us_strings[UVC_STRING_STREAMING_IDX].id = ret; + uvc_streaming_intf_alt0.iInterface = ret; + uvc_streaming_intf_alt1.iInterface = ret; + } /* Register the function. */ uvc->func.name = "uvc"; -- 2.7.4