diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/musb/musb_dsps.c | 89 | ||||
| -rw-r--r-- | drivers/usb/musb/musb_regs.h | 7 |
2 files changed, 90 insertions, 6 deletions
diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c index 53a4351aef9..f119a62140e 100644 --- a/drivers/usb/musb/musb_dsps.c +++ b/drivers/usb/musb/musb_dsps.c @@ -144,6 +144,7 @@ struct dsps_glue { const struct dsps_musb_wrapper *wrp; /* wrapper register offsets */ struct timer_list timer; /* otg_workaround timer */ unsigned long last_timer; /* last timer data for each instance */ + bool sw_babble_enabled; struct dsps_context context; struct debugfs_regset32 regset; @@ -477,6 +478,19 @@ static int dsps_musb_init(struct musb *musb) val &= ~(1 << wrp->otg_disable); dsps_writel(musb->ctrl_base, wrp->phy_utmi, val); + /* + * Check whether the dsps version has babble control enabled. + * In latest silicon revision the babble control logic is enabled. + * If MUSB_BABBLE_CTL returns 0x4 then we have the babble control + * logic enabled. + */ + val = dsps_readb(musb->mregs, MUSB_BABBLE_CTL); + if (val == MUSB_BABBLE_RCV_DISABLE) { + glue->sw_babble_enabled = true; + val |= MUSB_BABBLE_SW_SESSION_CTRL; + dsps_writeb(musb->mregs, MUSB_BABBLE_CTL, val); + } + ret = dsps_musb_dbg_init(musb, glue); if (ret) return ret; @@ -544,19 +558,82 @@ static int dsps_musb_set_mode(struct musb *musb, u8 mode) return 0; } +static bool sw_babble_control(struct musb *musb) +{ + u8 babble_ctl; + bool session_restart = false; + + babble_ctl = dsps_readb(musb->mregs, MUSB_BABBLE_CTL); + dev_dbg(musb->controller, "babble: MUSB_BABBLE_CTL value %x\n", + babble_ctl); + /* + * check line monitor flag to check whether babble is + * due to noise + */ + dev_dbg(musb->controller, "STUCK_J is %s\n", + babble_ctl & MUSB_BABBLE_STUCK_J ? "set" : "reset"); + + if (babble_ctl & MUSB_BABBLE_STUCK_J) { + int timeout = 10; + + /* + * babble is due to noise, then set transmit idle (d7 bit) + * to resume normal operation + */ + babble_ctl = dsps_readb(musb->mregs, MUSB_BABBLE_CTL); + babble_ctl |= MUSB_BABBLE_FORCE_TXIDLE; + dsps_writeb(musb->mregs, MUSB_BABBLE_CTL, babble_ctl); + + /* wait till line monitor flag cleared */ + dev_dbg(musb->controller, "Set TXIDLE, wait J to clear\n"); + do { + babble_ctl = dsps_readb(musb->mregs, MUSB_BABBLE_CTL); + udelay(1); + } while ((babble_ctl & MUSB_BABBLE_STUCK_J) && timeout--); + + /* check whether stuck_at_j bit cleared */ + if (babble_ctl & MUSB_BABBLE_STUCK_J) { + /* + * real babble condition has occurred + * restart the controller to start the + * session again + */ + dev_dbg(musb->controller, "J not cleared, misc (%x)\n", + babble_ctl); + session_restart = true; + } + } else { + session_restart = true; + } + + return session_restart; +} + static int dsps_musb_reset(struct musb *musb) { struct device *dev = musb->controller; struct dsps_glue *glue = dev_get_drvdata(dev->parent); const struct dsps_musb_wrapper *wrp = glue->wrp; + int session_restart = 0; - dsps_writel(musb->ctrl_base, wrp->control, (1 << wrp->reset)); - usleep_range(100, 200); - usb_phy_shutdown(musb->xceiv); - usleep_range(100, 200); - usb_phy_init(musb->xceiv); + if (glue->sw_babble_enabled) + session_restart = sw_babble_control(musb); + /* + * In case of new silicon version babble condition can be recovered + * without resetting the MUSB. But for older silicon versions, MUSB + * reset is needed + */ + if (session_restart || !glue->sw_babble_enabled) { + dev_info(musb->controller, "Restarting MUSB to recover from Babble\n"); + dsps_writel(musb->ctrl_base, wrp->control, (1 << wrp->reset)); + usleep_range(100, 200); + usb_phy_shutdown(musb->xceiv); + usleep_range(100, 200); + usb_phy_init(musb->xceiv); + session_restart = 1; + } - return 0; + return !session_restart; } static struct musb_platform_ops dsps_ops = { diff --git a/drivers/usb/musb/musb_regs.h b/drivers/usb/musb/musb_regs.h index 03f2655af29..b9bcda5e394 100644 --- a/drivers/usb/musb/musb_regs.h +++ b/drivers/usb/musb/musb_regs.h @@ -72,6 +72,12 @@ #define MUSB_DEVCTL_HR 0x02 #define MUSB_DEVCTL_SESSION 0x01 +/* BABBLE_CTL */ +#define MUSB_BABBLE_FORCE_TXIDLE 0x80 +#define MUSB_BABBLE_SW_SESSION_CTRL 0x40 +#define MUSB_BABBLE_STUCK_J 0x20 +#define MUSB_BABBLE_RCV_DISABLE 0x04 + /* MUSB ULPI VBUSCONTROL */ #define MUSB_ULPI_USE_EXTVBUS 0x01 #define MUSB_ULPI_USE_EXTVBUSIND 0x02 @@ -246,6 +252,7 @@ */ #define MUSB_DEVCTL 0x60 /* 8 bit */ +#define MUSB_BABBLE_CTL 0x61 /* 8 bit */ /* These are always controlled through the INDEX register */ #define MUSB_TXFIFOSZ 0x62 /* 8-bit (see masks) */ |