| spi_setup(9) - phpMan
SPI_SETUP(9) Serial Peripheral Interface (S SPI_SETUP(9)
NAME
spi_setup - setup SPI mode and clock rate
SYNOPSIS
int spi_setup(struct spi_device * spi);
ARGUMENTS
spi
the device whose settings are being modified
CONTEXT
can sleep, and no requests are queued to the device
DESCRIPTION
SPI protocol drivers may need to update the transfer mode if the device doesn't work with
its default. They may likewise need to update clock rates or word sizes from initial
values. This function changes those settings, and must be called from a context that can
sleep. Except for SPI_CS_HIGH, which takes effect immediately, the changes take effect the
next time the device is selected and data is transferred to or from it. When this function
returns, the spi device is deselected.
Note that this call will fail if the protocol driver specifies an option that the
underlying controller or its driver does not support. For example, not all hardware
supports wire transfers using nine bit words, LSB-first wire encoding, or active-high
chipselects.
RETURN
zero on success, else a negative error code.
COPYRIGHT
Kernel Hackers Manual 4.8. January 2017 SPI_SETUP(9)
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