| From 280a9045bb18833db921b316a5527d2b565e9f2e Mon Sep 17 00:00:00 2001 |
| From: Eugene Korenevsky <ekorenevsky@astralinux.ru> |
| Date: Sun, 10 Jan 2021 20:36:09 +0300 |
| Subject: ehci: fix EHCI host controller initialization sequence |
| |
| From: Eugene Korenevsky <ekorenevsky@astralinux.ru> |
| |
| commit 280a9045bb18833db921b316a5527d2b565e9f2e upstream. |
| |
| According to EHCI spec, EHCI HC clears USBSTS.HCHalted whenever |
| USBCMD.RS=1. |
| |
| However, it is a good practice to wait some time after setting USBCMD.RS |
| (approximately 100ms) until USBSTS.HCHalted become zero. |
| |
| Without this waiting, VirtualBox's EHCI virtual HC accidentally hangs |
| (see BugLink). |
| |
| BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=211095 |
| Acked-by: Alan Stern <stern@rowland.harvard.edu> |
| Signed-off-by: Eugene Korenevsky <ekorenevsky@astralinux.ru> |
| Cc: stable <stable@vger.kernel.org> |
| Link: https://lore.kernel.org/r/20210110173609.GA17313@himera.home |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/usb/host/ehci-hcd.c | 12 ++++++++++++ |
| 1 file changed, 12 insertions(+) |
| |
| --- a/drivers/usb/host/ehci-hcd.c |
| +++ b/drivers/usb/host/ehci-hcd.c |
| @@ -587,6 +587,7 @@ static int ehci_run (struct usb_hcd *hcd |
| struct ehci_hcd *ehci = hcd_to_ehci (hcd); |
| u32 temp; |
| u32 hcc_params; |
| + int rc; |
| |
| hcd->uses_new_polling = 1; |
| |
| @@ -642,9 +643,20 @@ static int ehci_run (struct usb_hcd *hcd |
| down_write(&ehci_cf_port_reset_rwsem); |
| ehci->rh_state = EHCI_RH_RUNNING; |
| ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag); |
| + |
| + /* Wait until HC become operational */ |
| ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */ |
| msleep(5); |
| + rc = ehci_handshake(ehci, &ehci->regs->status, STS_HALT, 0, 100 * 1000); |
| + |
| up_write(&ehci_cf_port_reset_rwsem); |
| + |
| + if (rc) { |
| + ehci_err(ehci, "USB %x.%x, controller refused to start: %d\n", |
| + ((ehci->sbrn & 0xf0)>>4), (ehci->sbrn & 0x0f), rc); |
| + return rc; |
| + } |
| + |
| ehci->last_periodic_enable = ktime_get_real(); |
| |
| temp = HC_VERSION(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase)); |