From d2570fc048ca1307e64572c825e0d7908bd60a21 Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Mon, 2 Jan 2012 13:35:41 +0200 Subject: [PATCH] usb: ch9: fix up MaxStreams helper commit 18b7ede5f7ee2092aedcb578d3ac30bd5d4fc23c upstream. [ removed the dwc3 portion of the patch as it didn't apply to older kernels - gregkh] According to USB 3.0 Specification Table 9-22, if bmAttributes [4:0] are set to zero, it means "no streams supported", but the way this helper was defined on Linux, we will *always* have one stream which might cause several problems. For example on DWC3, we would tell the controller endpoint has streams enabled and yet start transfers with Stream ID set to 0, which would goof up the host side. While doing that, convert the macro to an inline function due to the different checks we now need. Signed-off-by: Felipe Balbi Signed-off-by: Sarah Sharp Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 3 +-- include/linux/usb/ch9.h | 20 +++++++++++++++++++- 2 files changed, 20 insertions(+), 3 deletions(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 36f9dd81c49e..b33f0598ccfe 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -2797,8 +2797,7 @@ static int xhci_calculate_streams_and_bitmask(struct xhci_hcd *xhci, if (ret < 0) return ret; - max_streams = USB_SS_MAX_STREAMS( - eps[i]->ss_ep_comp.bmAttributes); + max_streams = usb_ss_max_streams(&eps[i]->ss_ep_comp); if (max_streams < (*num_streams - 1)) { xhci_dbg(xhci, "Ep 0x%x only supports %u stream IDs.\n", eps[i]->desc.bEndpointAddress, diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h index d5da6c68c250..61b29057b054 100644 --- a/include/linux/usb/ch9.h +++ b/include/linux/usb/ch9.h @@ -605,8 +605,26 @@ struct usb_ss_ep_comp_descriptor { } __attribute__ ((packed)); #define USB_DT_SS_EP_COMP_SIZE 6 + /* Bits 4:0 of bmAttributes if this is a bulk endpoint */ -#define USB_SS_MAX_STREAMS(p) (1 << ((p) & 0x1f)) +static inline int +usb_ss_max_streams(const struct usb_ss_ep_comp_descriptor *comp) +{ + int max_streams; + + if (!comp) + return 0; + + max_streams = comp->bmAttributes & 0x1f; + + if (!max_streams) + return 0; + + max_streams = 1 << max_streams; + + return max_streams; +} + /* Bits 1:0 of bmAttributes if this is an isoc endpoint */ #define USB_SS_MULT(p) (1 + ((p) & 0x3)) -- 2.39.2