diff options
Diffstat (limited to 'drivers/usb/host/ehci-omap.c')
| -rw-r--r-- | drivers/usb/host/ehci-omap.c | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/drivers/usb/host/ehci-omap.c b/drivers/usb/host/ehci-omap.c index c4ce4870875..1b215c25f68 100644 --- a/drivers/usb/host/ehci-omap.c +++ b/drivers/usb/host/ehci-omap.c @@ -28,21 +28,48 @@ static struct omap_ehci *const ehci = (struct omap_ehci *)OMAP_EHCI_BASE; static int omap_uhh_reset(void) { -/* - * Soft resetting the UHH module causes instability issues on - * all OMAPs so we just avoid it. - * - * See OMAP36xx Errata - * i571: USB host EHCI may stall when entering smart-standby mode - * i660: USBHOST Configured In Smart-Idle Can Lead To a Deadlock - * - * On OMAP4/5, soft-resetting the UHH module will put it into - * Smart-Idle mode and lead to a deadlock. - * - * On OMAP3, this doesn't seem to be the case but still instabilities - * are observed on beagle (3530 ES1.0) if soft-reset is used. - * e.g. NFS root failures with Linux kernel. - */ + int timeout = 0; + u32 rev; + + rev = readl(&uhh->rev); + + /* Soft RESET */ + writel(OMAP_UHH_SYSCONFIG_SOFTRESET, &uhh->sysc); + + switch (rev) { + case OMAP_USBHS_REV1: + /* Wait for soft RESET to complete */ + while (!(readl(&uhh->syss) & 0x1)) { + if (timeout > 100) { + printf("%s: RESET timeout\n", __func__); + return -1; + } + udelay(10); + timeout++; + } + + /* Set No-Idle, No-Standby */ + writel(OMAP_UHH_SYSCONFIG_VAL, &uhh->sysc); + break; + + default: /* Rev. 2 onwards */ + + udelay(2); /* Need to wait before accessing SYSCONFIG back */ + + /* Wait for soft RESET to complete */ + while ((readl(&uhh->sysc) & 0x1)) { + if (timeout > 100) { + printf("%s: RESET timeout\n", __func__); + return -1; + } + udelay(10); + timeout++; + } + + writel(OMAP_UHH_SYSCONFIG_VAL, &uhh->sysc); + break; + } + return 0; } |