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Subject[RFC PATCH 2/4] spi: spi-fsl-spi: relax message sanity checking a little
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The comment says that we should not allow changes (to
bits_per_word/speed_hz) while CS is active, and indeed the code below
does fsl_spi_setup_transfer() when the ->cs_change of the previous
spi_transfer was set (and for the very first transfer).

So the sanity checking is a bit too strict - we can change it to
follow the same logic as is used by the actual transfer loop.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
---
drivers/spi/spi-fsl-spi.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index 6d114daa178a..481b075689b5 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -370,13 +370,15 @@ static int fsl_spi_do_one_msg(struct spi_master *master,
int status;

/* Don't allow changes if CS is active */
- first = list_first_entry(&m->transfers, struct spi_transfer,
- transfer_list);
+ cs_change = 1;
list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (cs_change)
+ first = t;
+ cs_change = t->cs_change;
if ((first->bits_per_word != t->bits_per_word) ||
(first->speed_hz != t->speed_hz)) {
dev_err(&spi->dev,
- "bits_per_word/speed_hz should be same for the same SPI transfer\n");
+ "bits_per_word/speed_hz cannot change while CS is active\n");
return -EINVAL;
}
}
--
2.20.1
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