diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/usb/musb/ux500.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/drivers/usb/musb/ux500.c b/drivers/usb/musb/ux500.c index 13a392913769..0332fcd286f7 100644 --- a/drivers/usb/musb/ux500.c +++ b/drivers/usb/musb/ux500.c @@ -36,6 +36,68 @@ struct ux500_glue { }; #define glue_to_musb(g) platform_get_drvdata(g->musb) +static void ux500_musb_set_vbus(struct musb *musb, int is_on) +{ + u8 devctl; + unsigned long timeout = jiffies + msecs_to_jiffies(1000); + /* HDRC controls CPEN, but beware current surges during device + * connect. They can trigger transient overcurrent conditions + * that must be ignored. + */ + + devctl = musb_readb(musb->mregs, MUSB_DEVCTL); + + if (is_on) { + if (musb->xceiv->state == OTG_STATE_A_IDLE) { + /* start the session */ + devctl |= MUSB_DEVCTL_SESSION; + musb_writeb(musb->mregs, MUSB_DEVCTL, devctl); + /* + * Wait for the musb to set as A device to enable the + * VBUS + */ + while (musb_readb(musb->mregs, MUSB_DEVCTL) & 0x80) { + + if (time_after(jiffies, timeout)) { + dev_err(musb->controller, + "configured as A device timeout"); + break; + } + } + + } else { + musb->is_active = 1; + musb->xceiv->otg->default_a = 1; + musb->xceiv->state = OTG_STATE_A_WAIT_VRISE; + devctl |= MUSB_DEVCTL_SESSION; + MUSB_HST_MODE(musb); + } + } else { + musb->is_active = 0; + + /* NOTE: we're skipping A_WAIT_VFALL -> A_IDLE and jumping + * right to B_IDLE... + */ + musb->xceiv->otg->default_a = 0; + devctl &= ~MUSB_DEVCTL_SESSION; + MUSB_DEV_MODE(musb); + } + musb_writeb(musb->mregs, MUSB_DEVCTL, devctl); + + /* + * Devctl values will be updated after vbus goes below + * session_valid. The time taken depends on the capacitance + * on VBUS line. The max discharge time can be upto 1 sec + * as per the spec. Typically on our platform, it is 200ms + */ + if (!is_on) + mdelay(200); + + dev_dbg(musb->controller, "VBUS %s, devctl %02x\n", + usb_otg_state_string(musb->xceiv->state), + musb_readb(musb->mregs, MUSB_DEVCTL)); +} + static irqreturn_t ux500_musb_interrupt(int irq, void *__hci) { unsigned long flags; @@ -79,6 +141,8 @@ static int ux500_musb_exit(struct musb *musb) static const struct musb_platform_ops ux500_ops = { .init = ux500_musb_init, .exit = ux500_musb_exit, + + .set_vbus = ux500_musb_set_vbus, }; static int ux500_probe(struct platform_device *pdev) |