From: Sonic Zhang Date: Thu, 23 Jun 2011 21:07:54 +0000 (-0400) Subject: i2c-bfin-twi: abort transfer is MEM bit is reset unexpectedly X-Git-Tag: firefly_0821_release~3680^2~5099^2~1 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4a65163e3b2190445c1d94daa21d09c5af604d97;p=firefly-linux-kernel-4.4.55.git i2c-bfin-twi: abort transfer is MEM bit is reset unexpectedly Sometimes, the first I2C transmit interrupt is not serviced in time (like when higher priority interrupts take too long). Since the RESTART bit is not set before the next I2C clock, when the TWI handler is finally called, the I2C session is aborted (MEM bit is reset) and both SMITSERV and MCOMP int status bits are set. So when this happens, abort the transfer. Reported-by: Isabelle Leonardi Signed-off-by: Sonic Zhang Signed-off-by: Mike Frysinger Signed-off-by: Ben Dooks --- diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c index 52b545a795f2..cbc98aea5b09 100644 --- a/drivers/i2c/busses/i2c-bfin-twi.c +++ b/drivers/i2c/busses/i2c-bfin-twi.c @@ -193,7 +193,13 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface, return; } if (twi_int_status & MCOMP) { - if (iface->cur_mode == TWI_I2C_MODE_COMBINED) { + if ((read_MASTER_CTL(iface) & MEN) == 0 && + (iface->cur_mode == TWI_I2C_MODE_REPEAT || + iface->cur_mode == TWI_I2C_MODE_COMBINED)) { + iface->result = -1; + write_INT_MASK(iface, 0); + write_MASTER_CTL(iface, 0); + } else if (iface->cur_mode == TWI_I2C_MODE_COMBINED) { if (iface->readNum == 0) { /* set the read number to 1 and ask for manual * stop in block combine mode