diff options
| author | Suresh Mangipudi <smangipudi@nvidia.com> | 2011-04-12 19:40:35 +0530 |
|---|---|---|
| committer | Varun Colbert <vcolbert@nvidia.com> | 2011-05-02 18:04:23 -0700 |
| commit | e6354059de6a1231bf340753657bbb4ef16c17a0 (patch) | |
| tree | 635a37f9bb68632c38d6b29f184c4225689b2e46 | |
| parent | 9c4eac8a44eef360c2e5be07838fecc78096847f (diff) | |
usb: host: tegra: PORTSC.SUSP needs a delay
Delay of 4ms is needed after the SUSPEND bit in the PORTSC register is
programmed. The hardware would be set only after 4ms of delay.
Bug 812427
Change-Id: I5253928264112b429f78e6682e261a44820811db
Reviewed-on: http://git-master/r/27510
Reviewed-on: http://git-master/r/29974
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>
Reviewed-by: Suresh Mangipudi <smangipudi@nvidia.com>
Tested-by: Suresh Mangipudi <smangipudi@nvidia.com>
| -rw-r--r-- | drivers/usb/host/ehci-tegra.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c index 184c1783d6c7..a81046b93af7 100644 --- a/drivers/usb/host/ehci-tegra.c +++ b/drivers/usb/host/ehci-tegra.c @@ -127,6 +127,8 @@ static int tegra_ehci_hub_control( temp &= ~PORT_WKCONN_E; temp |= PORT_WKDISC_E | PORT_WKOC_E; ehci_writel(ehci, temp | PORT_SUSPEND, status_reg); + /* Need a 4ms delay before the controller goes to suspend */ + mdelay(4); /* * If a transaction is in progress, there may be a delay in @@ -411,6 +413,8 @@ static int tegra_usb_resume(struct usb_hcd *hcd) if ((val & PORT_POWER) && (val & PORT_PE)) { val |= PORT_SUSPEND; writel(val, &hw->port_status[0]); + /* Need a 4ms delay before the controller goes to suspend */ + mdelay(4); /* Wait until port suspend completes */ if (handshake(ehci, &hw->port_status[0], PORT_SUSPEND, |