Re: [PATCH v2 3/3] i2c: imx: Don't generate STOP condition if arbitration has been lost
From: Krzysztof Kozlowski <krzk@kernel.org>
Date: 2020-10-05 08:16:47
Also in:
linux-i2c, lkml, stable
On Fri, Oct 02, 2020 at 05:23:05PM +0200, Christian Eggers wrote:
If arbitration is lost, the master automatically changes to slave mode.
I2SR_IBB may or may not be reset by hardware. Raising a STOP condition
by resetting I2CR_MSTA has no effect and will not clear I2SR_IBB.
So calling i2c_imx_bus_busy() is not required and would busy-wait until
timeout.
Signed-off-by: Christian Eggers <ceggers@arri.de>
Cc: stable@vger.kernel.org # Requires trivial backporting, simple remove
# the 3rd argument from the calls to
# i2c_imx_bus_busy().
---
drivers/i2c/busses/i2c-imx.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)Tested (not extensively) on Vybrid VF500 (Toradex VF50): Tested-by: Krzysztof Kozlowski <krzk@kernel.org> The I2C on Vybrid VF500 still works fine (also bigger transfers). I did not test this actual condition (arbitration) but only a regular I2C driver (BQ27xxx fuel gauge). Obviously this only proves that regular operation is not broken... Best regards, Krzysztof _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel