Mathias, Are there any plans to backport this to the other kernels?
Looks like it landed upstream as f7fac17ca925faa03fc5eb854c081a24075f8bad
Thanks, Raul On Wed, May 22, 2019 at 02:27:29PM +0200, gregkh@linuxfoundation.org wrote:
This is a note to let you know that I've just added the patch titled
xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic()to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch.
The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.
If you have any questions about this process, please let me know.
From f7fac17ca925faa03fc5eb854c081a24075f8bad Mon Sep 17 00:00:00 2001 From: Andrey Smirnov andrew.smirnov@gmail.com Date: Wed, 22 May 2019 14:34:01 +0300 Subject: xhci: Convert xhci_handshake() to use readl_poll_timeout_atomic()
Xhci_handshake() implements the algorithm already captured by readl_poll_timeout_atomic(). Convert the former to use the latter to avoid repetition.
Turned out this patch also fixes a bug on the AMD Stoneyridge platform where usleep(1) sometimes takes over 10ms. This means a 5 second timeout can easily take over 15 seconds which will trigger the watchdog and reboot the system.
[Add info about patch fixing a bug to commit message -Mathias] Signed-off-by: Andrey Smirnov andrew.smirnov@gmail.com Tested-by: Raul E Rangel rrangel@chromium.org Reviewed-by: Raul E Rangel rrangel@chromium.org Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
drivers/usb/host/xhci.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 048a675bbc52..20db378a6012 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -9,6 +9,7 @@ */ #include <linux/pci.h> +#include <linux/iopoll.h> #include <linux/irq.h> #include <linux/log2.h> #include <linux/module.h> @@ -52,7 +53,6 @@ static bool td_on_ring(struct xhci_td *td, struct xhci_ring *ring) return false; } -/* TODO: copied from ehci-hcd.c - can this be refactored? */ /*
- xhci_handshake - spin reading hc until handshake completes or fails
- @ptr: address of hc register to be read
@@ -69,18 +69,16 @@ static bool td_on_ring(struct xhci_td *td, struct xhci_ring *ring) int xhci_handshake(void __iomem *ptr, u32 mask, u32 done, int usec) { u32 result;
- int ret;
- do {
result = readl(ptr);if (result == ~(u32)0) /* card removed */return -ENODEV;result &= mask;if (result == done)return 0;udelay(1);usec--;- } while (usec > 0);
- return -ETIMEDOUT;
- ret = readl_poll_timeout_atomic(ptr, result,
(result & mask) == done ||result == U32_MAX,1, usec);- if (result == U32_MAX) /* card removed */
return -ENODEV;- return ret;
} /* -- 2.21.0