From: Wolfgang Grandegger Date: Mon, 12 Dec 2011 15:09:28 +0000 (+0100) Subject: can: flexcan: fix irq flooding by clearing all interrupt sources X-Git-Tag: v3.3-rc4~34^2~48 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6e9d554fa6e481a848358c215f129432262123c0;p=platform%2Fupstream%2Fkernel-adaptation-pc.git can: flexcan: fix irq flooding by clearing all interrupt sources As pointed out by Reuben Dowle and Lothar Waßmann, the TWRN_INT, RWRN_INT, BOFF_INT interrupt sources need to be cleared as well to avoid interrupt flooding, at least for the Flexcan on i.MX28 SOCs. Furthermore, the interrupts are only cleared, if really one of those interrupt sources are pending (which is not the case for rx and tx done). Cc: Reuben Dowle Cc: Lothar Waßmann Signed-off-by: Wolfgang Grandegger Signed-off-by: Marc Kleine-Budde --- diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 7fd8089..96d2357 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -118,6 +118,9 @@ (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT) #define FLEXCAN_ESR_ERR_ALL \ (FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE) +#define FLEXCAN_ESR_ALL_INT \ + (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \ + FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT) /* FLEXCAN interrupt flag register (IFLAG) bits */ #define FLEXCAN_TX_BUF_ID 8 @@ -577,7 +580,9 @@ static irqreturn_t flexcan_irq(int irq, void *dev_id) reg_iflag1 = flexcan_read(®s->iflag1); reg_esr = flexcan_read(®s->esr); - flexcan_write(FLEXCAN_ESR_ERR_INT, ®s->esr); /* ACK err IRQ */ + /* ACK all bus error and state change IRQ sources */ + if (reg_esr & FLEXCAN_ESR_ALL_INT) + flexcan_write(reg_esr & FLEXCAN_ESR_ALL_INT, ®s->esr); /* * schedule NAPI in case of: