On Thu, Feb 09, 2012 at 10:21:45PM +0100, Uwe Kleine-König wrote: > The chip select line was configured as output with the initial value > being active explicitly. It was later deasserted during > spi_bitbang_setup() without any clock activity in between. So it makes > no sense to activate the device at all and the chip select line can > better start non-active. > > Signed-off-by: Uwe Kleine-König <[email protected]> > --- > Hello, > > I'm not sure if an active chip select line without any clock activity can > confuse a device. If so, this patch might qualify as fix. But with my > limited knowledge about spi it's also possible that I just miss why the > active chip select is important. For the devices I have it doesn't seem > to make a difference. ping
> > Best regards > Uwe > > drivers/spi/spi-gpio.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c > index 0094c64..0b56cfc 100644 > --- a/drivers/spi/spi-gpio.c > +++ b/drivers/spi/spi-gpio.c > @@ -235,7 +235,8 @@ static int spi_gpio_setup(struct spi_device *spi) > status = gpio_request(cs, dev_name(&spi->dev)); > if (status) > return status; > - status = gpio_direction_output(cs, spi->mode & > SPI_CS_HIGH); > + status = gpio_direction_output(cs, > + !(spi->mode & SPI_CS_HIGH)); > } > } > if (!status) > -- > 1.7.9 > > -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ spi-devel-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/spi-devel-general
