From: Haikun Wang Date: Wed, 13 May 2015 10:12:15 +0000 (+0800) Subject: spi: spi-fsl-dspi: Bug fix incorrect CS de-assert X-Git-Tag: firefly_0821_release~176^2~1599^2~6^2 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=9deef024a12ebae4965c89837f662905ac88944b;p=firefly-linux-kernel-4.4.55.git spi: spi-fsl-dspi: Bug fix incorrect CS de-assert SPI chip select signal need to keep asserted between several spi_transfer in the same spi_message usually. But the driver will de-assert CS signal and the assert it between serval spi_transfer in the same spi_message under some condiations. This patch fix the bug. Here is an example: Assume you have two variables like the following, struct spi_transfer a; struct spi_transfer b; if you send a spi_message only includes 'a' first, and then you send a spi_message includes 'a' and 'b' but without resetting 'a'. Driver will de-assert CS and then assert CS between 'a' and 'b'. Signed-off-by: Haikun Wang Signed-off-by: Mark Brown --- diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c index 5fe54cda309f..8af20aa65abf 100644 --- a/drivers/spi/spi-fsl-dspi.c +++ b/drivers/spi/spi-fsl-dspi.c @@ -341,10 +341,10 @@ static int dspi_transfer_one_message(struct spi_master *master, dspi->cur_msg = message; dspi->cur_chip = spi_get_ctldata(spi); dspi->cs = spi->chip_select; + dspi->cs_change = 0; if (dspi->cur_transfer->transfer_list.next == &dspi->cur_msg->transfers) - transfer->cs_change = 1; - dspi->cs_change = transfer->cs_change; + dspi->cs_change = 1; dspi->void_write_data = dspi->cur_chip->void_write_data; dspi->dataflags = 0;