From c3897aa5386faba77e5bbdf94902a1658d3a5b11 Mon Sep 17 00:00:00 2001 From: Sarah Sharp Date: Thu, 18 Apr 2013 10:02:03 -0700 Subject: [PATCH] xhci: Disable D3cold for buggy TI redrivers. Some xHCI hosts contain a "redriver" from TI that silently drops port status connect changes if the port slips into Compliance Mode. If the port slips into compliance mode while the host is in D0, there will not be a port status change event. If the port slips into compliance mode while the host is in D3, the host will not send a PME. This includes when the system is suspended (S3) or hibernated (S4). If this happens when the system is in S3/S4, there is nothing software can do. Other port status change events that would normally cause the host to wake the system from S3/S4 may also be lost. This includes remote wakeup, disconnects and connects on other ports, and overrcurrent events. A decision was made to _NOT_ disable system suspend/hibernate on these systems, since users are unlikely to enable wakeup from S3/S4 for the xHCI host. Software can deal with this issue when the system is in S0. A work around was put in to poll the port status registers for Compliance Mode. The xHCI driver will continue to poll the registers while the host is runtime suspended. Unfortunately, that means we can't allow the PCI device to go into D3cold, because power will be removed from the host, and the config space will read as all Fs. Disable D3cold in the xHCI PCI runtime suspend function. This patch should be backported to kernels as old as 3.2, that contain the commit 71c731a296f1b08a3724bd1b514b64f1bda87a23 "usb: host: xhci: Fix Compliance Mode on SN65LVPE502CP Hardware" Signed-off-by: Sarah Sharp Cc: Huang Ying Cc: stable@vger.kernel.org --- drivers/usb/host/xhci-pci.c | 8 ++++++++ drivers/usb/host/xhci.c | 4 ++-- drivers/usb/host/xhci.h | 3 +++ 3 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 1a30c380043c..cc24e39b97d5 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -221,6 +221,14 @@ static void xhci_pci_remove(struct pci_dev *dev) static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup) { struct xhci_hcd *xhci = hcd_to_xhci(hcd); + struct pci_dev *pdev = to_pci_dev(hcd->self.controller); + + /* + * Systems with the TI redriver that loses port status change events + * need to have the registers polled during D3, so avoid D3cold. + */ + if (xhci_compliance_mode_recovery_timer_quirk_check()) + pdev->no_d3cold = true; return xhci_suspend(xhci); } diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index ae59119ed087..d8f640b12dd9 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -466,7 +466,7 @@ static void compliance_mode_recovery_timer_init(struct xhci_hcd *xhci) * Systems: * Vendor: Hewlett-Packard -> System Models: Z420, Z620 and Z820 */ -static bool compliance_mode_recovery_timer_quirk_check(void) +bool xhci_compliance_mode_recovery_timer_quirk_check(void) { const char *dmi_product_name, *dmi_sys_vendor; @@ -517,7 +517,7 @@ int xhci_init(struct usb_hcd *hcd) xhci_dbg(xhci, "Finished xhci_init\n"); /* Initializing Compliance Mode Recovery Data If Needed */ - if (compliance_mode_recovery_timer_quirk_check()) { + if (xhci_compliance_mode_recovery_timer_quirk_check()) { xhci->quirks |= XHCI_COMP_MODE_QUIRK; compliance_mode_recovery_timer_init(xhci); } diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 29c978e37135..77600cefcaf1 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1853,4 +1853,7 @@ struct xhci_input_control_ctx *xhci_get_input_control_ctx(struct xhci_hcd *xhci, struct xhci_slot_ctx *xhci_get_slot_ctx(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx); struct xhci_ep_ctx *xhci_get_ep_ctx(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx, unsigned int ep_index); +/* xHCI quirks */ +bool xhci_compliance_mode_recovery_timer_quirk_check(void); + #endif /* __LINUX_XHCI_HCD_H */ -- 2.39.5