Re: [RFC][PATCH] spi: Setup the master controller driver before setting the chipselect

From: Ivan T. Ivanov
Date: Wed Oct 14 2015 - 05:47:14 EST


Adding Andy.


> On Oct 13, 2015, at 12:01 AM, Franklin S Cooper Jr <fcooper@xxxxxx> wrote:
>
> Some devices depend on the master controller driver setup function being
> called before calling any chipselect functions.
>
> Insure that this is done otherwise uninitialized structures may be
> accessed causing a kernel panic.
>
> Signed-off-by: Franklin S Cooper Jr <fcooper@xxxxxx>
> ---
> drivers/spi/spi.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
> index 38006cc..9374d82 100644
> --- a/drivers/spi/spi.c
> +++ b/drivers/spi/spi.c
> @@ -2053,11 +2053,11 @@ int spi_setup(struct spi_device *spi)
> if (!spi->max_speed_hz)
> spi->max_speed_hz = spi->master->max_speed_hz;
>
> - spi_set_cs(spi, false);
> -
> if (spi->master->setup)
> status = spi->master->setup(spi);
>
> + spi_set_cs(spi, false);
> +
> dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n",
> (int) (spi->mode & (SPI_CPOL | SPI_CPHA)),
> (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "",
> --
> 2.6.1
>
> --
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