From 2806e6ad77c71dd2538cb698aad476e8cf3af004 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Tue, 9 Jan 2018 14:58:58 +0100 Subject: [PATCH] i2c: send STOP after successful bus recovery If we managed to get a client release SDA again, send a STOP afterwards to make sure we have a consistent state on the bus again. Tested-by: Phil Reid Signed-off-by: Wolfram Sang Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core-base.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 54cef80990a1..23f353630db3 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -199,6 +199,18 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap) if (bri->get_sda && !bri->get_sda(adap)) ret = -EBUSY; + /* If all went well, send STOP for a sane bus state. */ + if (ret == 0 && bri->set_sda) { + bri->set_scl(adap, 0); + ndelay(RECOVERY_NDELAY / 2); + bri->set_sda(adap, 0); + ndelay(RECOVERY_NDELAY / 2); + bri->set_scl(adap, 1); + ndelay(RECOVERY_NDELAY / 2); + bri->set_sda(adap, 1); + ndelay(RECOVERY_NDELAY / 2); + } + if (bri->unprepare_recovery) bri->unprepare_recovery(adap);