spi/atmel: let transfers through if not changing bits_per_word

bits_per_word option in spi_transfer are allowed if it does not change
the csr register.

This is necessary for the driver in
drivers/staging/iio/adis16260_core.c, as it uses this option.

Signed-off-by: Matthias Brugger <mensch0815@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Matthias Brugger 2010-10-13 17:51:02 +02:00 коммит произвёл Grant Likely
Родитель 8e41b527ff
Коммит b9d228f9e8
1 изменённых файлов: 13 добавлений и 1 удалений

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@ -654,6 +654,8 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg)
struct spi_transfer *xfer;
unsigned long flags;
struct device *controller = spi->master->dev.parent;
u8 bits;
struct atmel_spi_device *asd;
as = spi_master_get_devdata(spi->master);
@ -672,8 +674,18 @@ static int atmel_spi_transfer(struct spi_device *spi, struct spi_message *msg)
return -EINVAL;
}
if (xfer->bits_per_word) {
asd = spi->controller_state;
bits = (asd->csr >> 4) & 0xf;
if (bits != xfer->bits_per_word - 8) {
dev_dbg(&spi->dev, "you can't yet change "
"bit_per_word in transfers\n");
return -ENOPROTOOPT;
}
}
/* FIXME implement these protocol options!! */
if (xfer->bits_per_word || xfer->speed_hz) {
if (xfer->speed_hz) {
dev_dbg(&spi->dev, "no protocol options yet\n");
return -ENOPROTOOPT;
}