Re: Sending one byte transfers using SPI bus with linux-2.6.32

["Kevyn-Alexandre Paré" <kapare-7qmld2CjetYf4mhTGKTGE9BPR1lH4CV8@public.gmane.org>]

A simple git diff should have save us some time ;)

git diff v2.6.32 v2.6.36 -- spidev_test.c
warning: refname 'v2.6.32' is ambiguous.
diff --git a/Documentation/spi/spidev_test.c
b/Documentation/spi/spidev_test.c
index 10abd37..16feda9 100644
--- a/Documentation/spi/spidev_test.c
+++ b/Documentation/spi/spidev_test.c
@@ -58,7 +58,7 @@ static void transfer(int fd)
        };
 
        ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
-       if (ret == 1)
+       if (ret < 1)
                pabort("can't send spi message");
 
        for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {

-- kap

On Sun, 2011-03-06 at 21:45 +0400, Elvis Dowson wrote:
> Hi,
>         The problem was in the spidev_test.c program itself, in linux-2.6.32.
> 
> After applying the following patch taken from linux-2.6.34, 1 byte transfers work.
> 
> http://git.kernel.org/?p=linux/kernel/git/longterm/linux-2.6.34.y.git;a=blobdiff;f=Documentation/spi/spidev_test.c;h=16feda9014692a87a4996bf51d759ab9e7500ee5;hp=10abd3773e49122aab0dfad27f7cb2c91b8d5d08;hb=95b1ed2ac7ffe3205afc6f5a20320fbdb984da92;hpb=dda04c7bcf58cb02ac796beb1cf483aa5277f2af
> 
> Elvis Dowson



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