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Subject[PATCH] spi: bcm2835aux: use 64-bit arithmetic instead of 32-bit
Add suffix ULL to constant 9 in order to give the compiler complete
information about the proper arithmetic to use. Notice that this
constant is used in a context that expects an expression of type
unsigned long long (64 bits, unsigned).

The expression tfr->len * 9 * 1000000 is currently being evaluated
using 32-bit arithmetic.

Addresses-Coverity-ID: 1339619
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
drivers/spi/spi-bcm2835aux.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c
index 7428091..a768c23 100644
--- a/drivers/spi/spi-bcm2835aux.c
+++ b/drivers/spi/spi-bcm2835aux.c
@@ -363,7 +363,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master,
* chunk getting transferred - in our case the chunk size
* is 3 bytes, so we approximate this by 9 bits/byte
*/
- xfer_time_us = tfr->len * 9 * 1000000;
+ xfer_time_us = tfr->len * 9ULL * 1000000;
do_div(xfer_time_us, spi_used_hz);

/* run in polling mode for short transfers */
--
2.7.4
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