diff options
| author | Eugene Korenevsky <ekorenevsky@astralinux.ru> | 2021-01-10 20:36:09 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-01-30 15:25:56 +0300 |
| commit | c2a8cb52e1fe529b9500459548fe389ff911563f (patch) | |
| tree | e4bf65ffff640c3988575ffbd643e8d448152114 | |
| parent | 1148a9f140a99037be4aba8dc0fb5a9181151146 (diff) | |
| download | linux-c2a8cb52e1fe529b9500459548fe389ff911563f.tar.xz | |
ehci: fix EHCI host controller initialization sequence
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>
| -rw-r--r-- | drivers/usb/host/ehci-hcd.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 330e05acf5f7..b9ad19d1b400 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -575,6 +575,7 @@ 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; @@ -630,9 +631,20 @@ 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)); |