lkml.org 
[lkml]   [2012]   [Dec]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH RFC] spidev.c: add sysfs attributes for SPI configuration
Date
On Sat, 24 Nov 2012 18:20:08 +0100, Federico Vaga <federico.vaga@gmail.com> wrote:
> This patch introduce the use of the sysfs attribute for the spidev
> configuration. This avoid the user to have a specific program which does
> ioctl() on spidev. The user can easily does cat (to read) and echo (to
> write) on the sysfs file and configure SPI.
>
> The patch exports the following attributes: bits-per-word, lsb-first,
> mode and speed-hz.
>
> Example:
> # cat /sys/bus/spi/devices/spi1.0/speed-hz
> 500000
> # echo 450000 > /sys/bus/spi/devices/spi1.0/speed-hz
> # dmesg | tail -n 4
> spidev spi1.0: DEactivate 60, mr 000f0011
> spidev spi1.0: setup: 449447 Hz bpw 8 mode 0x0 -> csr0 0000dd02
> spidev spi1.0: setup mode 0, 8 bits/w, 450000 Hz max --> 0
> spidev spi1.0: 450000 Hz (max)
>
> Signed-off-by: Federico Vaga <federico.vaga@gmail.com>

Not a good idea. sysfs is not a good place for operational interfaces.
Please use the spi character devices for direct manipulation of the SPI
configuration.

g.


\
 
 \ /
  Last update: 2012-12-19 17:01    [W:0.056 / U:0.520 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site