diff options
Diffstat (limited to 'include/linux/spi/spi_bitbang.h')
| -rw-r--r-- | include/linux/spi/spi_bitbang.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h index bf8de281b4e..eed4254bd50 100644 --- a/include/linux/spi/spi_bitbang.h +++ b/include/linux/spi/spi_bitbang.h @@ -83,6 +83,13 @@ extern int spi_bitbang_stop(struct spi_bitbang *spi); * int getmiso(struct spi_device *); * void spidelay(unsigned); * + * setsck()'s is_on parameter is a zero/nonzero boolean. + * + * setmosi()'s is_on parameter is a zero/nonzero boolean. + * + * getmiso() is required to return 0 or 1 only. Any other value is invalid + * and will result in improper operation. + * * A non-inlined routine would call bitbang_txrx_*() routines. The * main loop could easily compile down to a handful of instructions, * especially if the delay is a NOP (to run at peak speed). |