spi: dw: fix multiple slaves with different baudrates
Add current master clock to dws struct and compare it against the
requestedtransfer speed. Update clock divider only if necessary.
Signed-off-by: Matthias Seidel <kernel@mseidel.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
index c09bb74..c85e4b3 100644
--- a/drivers/spi/spi-dw.c
+++ b/drivers/spi/spi-dw.c
@@ -283,7 +283,6 @@
struct chip_data *chip = spi_get_ctldata(spi);
u8 imask = 0;
u16 txlevel = 0;
- u16 clk_div;
u32 cr0;
int ret;
@@ -298,13 +297,13 @@
spi_enable_chip(dws, 0);
/* Handle per transfer options for bpw and speed */
- if (transfer->speed_hz != chip->speed_hz) {
- /* clk_div doesn't support odd number */
- clk_div = (dws->max_freq / transfer->speed_hz + 1) & 0xfffe;
-
- chip->speed_hz = transfer->speed_hz;
- chip->clk_div = clk_div;
-
+ if (transfer->speed_hz != dws->current_freq) {
+ if (transfer->speed_hz != chip->speed_hz) {
+ /* clk_div doesn't support odd number */
+ chip->clk_div = (dws->max_freq / transfer->speed_hz + 1) & 0xfffe;
+ chip->speed_hz = transfer->speed_hz;
+ }
+ dws->current_freq = transfer->speed_hz;
spi_set_clk(dws, chip->clk_div);
}
if (transfer->bits_per_word == 8) {