From: Abhishek Sahu absahu@codeaurora.org
commit 7239872fb3400b21a8f5547257f9f86455867bd6 upstream.
The QUP BSLP BAM generates the following error sometimes if the current I2C DMA transfer fails and the flush operation has been scheduled
“bam-dma-engine 7884000.dma: Cannot free busy channel”
If any I2C error comes during BAM DMA transfer, then the QUP I2C interrupt will be generated and the flush operation will be carried out to make I2C consume all scheduled DMA transfer. Currently, the same completion structure is being used for BAM transfer which has already completed without reinit. It will make flush operation wait_for_completion_timeout completed immediately and will proceed for freeing the DMA resources where the descriptors are still in process.
Signed-off-by: Abhishek Sahu absahu@codeaurora.org Acked-by: Sricharan R sricharan@codeaurora.org Reviewed-by: Austin Christ austinwc@codeaurora.org Reviewed-by: Andy Gross andy.gross@linaro.org Signed-off-by: Wolfram Sang wsa@the-dreams.de Signed-off-by: Amit Pundir amit.pundir@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/i2c/busses/i2c-qup.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -844,6 +844,8 @@ static int qup_i2c_bam_do_xfer(struct qu }
if (ret || qup->bus_err || qup->qup_err) { + reinit_completion(&qup->xfer); + if (qup_i2c_change_state(qup, QUP_RUN_STATE)) { dev_err(qup->dev, "change to run state timed out"); goto desc_err;