From 8acc8296f94349e7a933dd97e8f5d0ec16d4b4db Mon Sep 17 00:00:00 2001 From: Robert Baldyga Date: Thu, 19 Sep 2013 11:50:23 +0200 Subject: [PATCH] usb: gadget: s3c-hsotg: fix interrupt configuration in dedicated-fifo mode In dedicated-fifo mode TxFIFOEmpty interrupt should be asserted when TxFIFO for this endpoint is completly empty, so NPTxFEmpLvl and PTxFEmpLvl bits are set in GAHBCFG register. In DIEPMSK register INTknTXFEmpMsk is set, becouse it's needed to indicate FIFO Empty state. Signed-off-by: Robert Baldyga Signed-off-by: Kyungmin Park Signed-off-by: Felipe Balbi --- drivers/usb/gadget/s3c-hsotg.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c index 70615585b48d..a9cae1ff0449 100644 --- a/drivers/usb/gadget/s3c-hsotg.c +++ b/drivers/usb/gadget/s3c-hsotg.c @@ -2304,15 +2304,19 @@ static void s3c_hsotg_core_init(struct s3c_hsotg *hsotg) GAHBCFG_HBstLen_Incr4, hsotg->regs + GAHBCFG); else - writel(GAHBCFG_GlblIntrEn, hsotg->regs + GAHBCFG); + writel(((hsotg->dedicated_fifos) ? (GAHBCFG_NPTxFEmpLvl | + GAHBCFG_PTxFEmpLvl) : 0) | + GAHBCFG_GlblIntrEn, + hsotg->regs + GAHBCFG); /* - * Enabling INTknTXFEmpMsk here seems to be a big mistake, we end - * up being flooded with interrupts if the host is polling the - * endpoint to try and read data. + * If INTknTXFEmpMsk is enabled, it's important to disable ep interrupts + * when we have no data to transfer. Otherwise we get being flooded by + * interrupts. */ - writel(((hsotg->dedicated_fifos) ? DIEPMSK_TxFIFOEmpty : 0) | + writel(((hsotg->dedicated_fifos) ? DIEPMSK_TxFIFOEmpty | + DIEPMSK_INTknTXFEmpMsk : 0) | DIEPMSK_EPDisbldMsk | DIEPMSK_XferComplMsk | DIEPMSK_TimeOUTMsk | DIEPMSK_AHBErrMsk | DIEPMSK_INTknEPMisMsk, -- 2.30.2