From 4c1bd3d7a7d114dabd58f62f386ac4bfd268be1f Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Mon, 24 Aug 2009 14:44:30 +0100 Subject: [PATCH] USB: make urb scatter-gather support more generic The WHCI HCD will also support urbs with scatter-gather lists. Add a usb_bus field to indicated how many sg list elements are supported by the HCD. Use this to decide whether to pass the scatter-list to the HCD or not. Make the usb-storage driver use this new field. Signed-off-by: David Vrabel Cc: Alan Stern Cc: Sarah Sharp Cc: Matthew Dharm Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/message.c | 8 +------- drivers/usb/host/xhci-pci.c | 2 ++ drivers/usb/storage/usb.c | 10 ++++++++++ include/linux/usb.h | 1 + 4 files changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index e80f1af438c8..8d874cad6581 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -393,13 +393,7 @@ int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev, if (io->entries <= 0) return io->entries; - /* If we're running on an xHCI host controller, queue the whole scatter - * gather list with one call to urb_enqueue(). This is only for bulk, - * as that endpoint type does not care how the data gets broken up - * across frames. - */ - if (usb_pipebulk(pipe) && - bus_to_hcd(dev->bus)->driver->flags & HCD_USB3) { + if (dev->bus->sg_tablesize > 0) { io->urbs = kmalloc(sizeof *io->urbs, mem_flags); use_sg = true; } else { diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 06595ec27bb7..e097008d6fb1 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -54,6 +54,8 @@ static int xhci_pci_setup(struct usb_hcd *hcd) struct pci_dev *pdev = to_pci_dev(hcd->self.controller); int retval; + hcd->self.sg_tablesize = TRBS_PER_SEGMENT - 1; + xhci->cap_regs = hcd->regs; xhci->op_regs = hcd->regs + HC_LENGTH(xhci_readl(xhci, &xhci->cap_regs->hc_capbase)); diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c index 01e43a13a6bf..1599d86154c4 100644 --- a/drivers/usb/storage/usb.c +++ b/drivers/usb/storage/usb.c @@ -843,6 +843,15 @@ static int usb_stor_scan_thread(void * __us) complete_and_exit(&us->scanning_done, 0); } +static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf) +{ + struct usb_device *usb_dev = interface_to_usbdev(intf); + + if (usb_dev->bus->sg_tablesize) { + return usb_dev->bus->sg_tablesize; + } + return SG_ALL; +} /* First part of general USB mass-storage probing */ int usb_stor_probe1(struct us_data **pus, @@ -871,6 +880,7 @@ int usb_stor_probe1(struct us_data **pus, * Allow 16-byte CDBs and thus > 2TB */ host->max_cmd_len = 16; + host->sg_tablesize = usb_stor_sg_tablesize(intf); *pus = us = host_to_us(host); memset(us, 0, sizeof(struct us_data)); mutex_init(&(us->dev_mutex)); diff --git a/include/linux/usb.h b/include/linux/usb.h index a34fa89f1474..6e91ee4f5b81 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -331,6 +331,7 @@ struct usb_bus { u8 otg_port; /* 0, or number of OTG/HNP port */ unsigned is_b_host:1; /* true during some HNP roleswitches */ unsigned b_hnp_enable:1; /* OTG: did A-Host enable HNP? */ + unsigned sg_tablesize; /* 0 or largest number of sg list entries */ int devnum_next; /* Next open device number in * round-robin allocation */ -- 2.20.1