From 29e75a264486ea2e7b698eceed2b33292b8f01bb Mon Sep 17 00:00:00 2001 From: leoliu-oc Date: Mon, 15 Jan 2024 17:13:47 +0800 Subject: [PATCH] USB: Fix ehci infinite suspend-resume loop issue in zhaoxin ANBZ: #2608 commit f085bd4bfe0907ce2fad2c787fc65871ec5ca6d6 upstream. In zhaoxin platform, some ehci projects will latch a wakeup signal internal when plug in a device on port during system S0. This wakeup signal will turn on when ehci runtime suspend, which will trigger a system control interrupt that will resume ehci back to D0. As no device connect, ehci will be set to runtime suspend and turn on the internal latched wakeup signal again. It will cause a suspend-resume loop and generate system control interrupt continuously. Fixed this issue by clear wakeup signal latched in ehci internal when ehci resume callback is called. Acked-by: Alan Stern Signed-off-by: Weitao Wang Link: https://lore.kernel.org/r/20220324121735.3803-1-WeitaoWang-oc@zhaoxin.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: leoliu-oc --- drivers/usb/host/ehci-hcd.c | 23 +++++++++++++++++++++++ drivers/usb/host/ehci-pci.c | 4 ++++ drivers/usb/host/ehci.h | 1 + 3 files changed, 28 insertions(+) diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index f0a0ddee52d0..a2252b99a4f4 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -1077,6 +1077,26 @@ static void ehci_remove_device(struct usb_hcd *hcd, struct usb_device *udev) #ifdef CONFIG_PM +/* Clear wakeup signal locked in zhaoxin platform when device plug in. */ +static void ehci_zx_wakeup_clear(struct ehci_hcd *ehci) +{ + u32 __iomem *reg = &ehci->regs->port_status[4]; + u32 t1 = ehci_readl(ehci, reg); + + t1 &= (u32)~0xf0000; + t1 |= PORT_TEST_FORCE; + ehci_writel(ehci, t1, reg); + t1 = ehci_readl(ehci, reg); + msleep(1); + t1 &= (u32)~0xf0000; + ehci_writel(ehci, t1, reg); + ehci_readl(ehci, reg); + msleep(1); + t1 = ehci_readl(ehci, reg); + ehci_writel(ehci, t1 | PORT_CSC, reg); + ehci_readl(ehci, reg); +} + /* suspend/resume, section 4.3 */ /* These routines handle the generic parts of controller suspend/resume */ @@ -1128,6 +1148,9 @@ int ehci_resume(struct usb_hcd *hcd, bool force_reset) if (ehci->shutdown) return 0; /* Controller is dead */ + if (ehci->zx_wakeup_clear_needed) + ehci_zx_wakeup_clear(ehci); + /* * If CF is still set and reset isn't forced * then we maintained suspend power. diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c index fe9422d3bcdc..cba03a042a29 100644 --- a/drivers/usb/host/ehci-pci.c +++ b/drivers/usb/host/ehci-pci.c @@ -216,6 +216,10 @@ static int ehci_pci_setup(struct usb_hcd *hcd) ehci_info(ehci, "applying MosChip frame-index workaround\n"); ehci->frame_index_bug = 1; break; + case PCI_VENDOR_ID_ZHAOXIN: + if (pdev->device == 0x3104 && (pdev->revision & 0xf0) == 0x90) + ehci->zx_wakeup_clear_needed = 1; + break; } /* optional debug port, normally in the first BAR */ diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h index c8e9a48e1d51..df4a13733c40 100644 --- a/drivers/usb/host/ehci.h +++ b/drivers/usb/host/ehci.h @@ -218,6 +218,7 @@ struct ehci_hcd { /* one per controller */ unsigned frame_index_bug:1; /* MosChip (AKA NetMos) */ unsigned need_oc_pp_cycle:1; /* MPC834X port power */ unsigned imx28_write_fix:1; /* For Freescale i.MX28 */ + unsigned zx_wakeup_clear_needed:1; /* required for usb32 quirk */ #define OHCI_CTRL_HCFS (3 << 6) -- Gitee