From: Sonic Zhang Date: Wed, 13 Jun 2012 08:22:42 +0000 (+0800) Subject: i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves. X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a25733d6f6968240042ac94dc93c7ae3c9e8d68b;p=linux-beck.git i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves. Some fault i2c device may hold the sda/scl line and cause i2c driver wait in the BUS busy loop. The I2C framework already retry the transfer loop before timeout. Return -EAGAIN instead of pull BUSBUSY in the other loop. Signed-off-by: Sonic Zhang Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c index 4799c6886946..5fb5f3ee13a2 100644 --- a/drivers/i2c/busses/i2c-bfin-twi.c +++ b/drivers/i2c/busses/i2c-bfin-twi.c @@ -307,8 +307,8 @@ static int bfin_twi_do_master_xfer(struct i2c_adapter *adap, if (!(read_CONTROL(iface) & TWI_ENA)) return -ENXIO; - while (read_MASTER_STAT(iface) & BUSBUSY) - yield(); + if (read_MASTER_STAT(iface) & BUSBUSY) + return -EAGAIN; iface->pmsg = msgs; iface->msg_num = num; @@ -407,8 +407,8 @@ int bfin_twi_do_smbus_xfer(struct i2c_adapter *adap, u16 addr, if (!(read_CONTROL(iface) & TWI_ENA)) return -ENXIO; - while (read_MASTER_STAT(iface) & BUSBUSY) - yield(); + if (read_MASTER_STAT(iface) & BUSBUSY) + return -EAGAIN; iface->writeNum = 0; iface->readNum = 0;