lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

SPI controller drivers: check for unsupported modes

Browse Source 
Minor SPI controller driver updates: make the setup() methods reject
spi->mode bits they don't support, by masking aginst the inverse of bits
they *do* support.  This insures against misbehavior later when new mode
bits get added.

Most controllers can't support SPI_LSB_FIRST; more handle SPI_CS_HIGH.
Support for all four SPI clock/transfer modes is routine.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Brownell
2007-07-17 04:04:02 -07:00
committed by Linus Torvalds
parent ff294cba8a
commit dccd573bb0
10 changed files with 66 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/spi/spi_bitbang.c
View File

@@ -187,12 +187,10 @@ int spi_bitbang_setup(struct spi_device *spi)
bitbang = spi_master_get_devdata(spi->master);
/* REVISIT: some systems will want to support devices using lsb-first
* bit encodings on the wire. In pure software that would be trivial,
* just bitbang_txrx_le_cphaX() routines shifting the other way, and
* some hardware controllers also have this support.
/* Bitbangers can support SPI_CS_HIGH, SPI_3WIRE, and so on;
* add those to master->flags, and provide the other support.
*/
if ((spi->mode & SPI_LSB_FIRST) != 0)
if ((spi->mode & ~(SPI_CPOL|SPI_CPHA|bitbang->flags)) != 0)
return -EINVAL;
if (!cs) {