spi: bcm-qspi: set transfer parameter only if they change

Check if the transfer parameters have changed from previous settings
before applying new parameters.

Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com>
Link: https://lore.kernel.org/r/20211124193353.32311-3-kdasu.kdev@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index 38e6e2c..c9a769b 100644 (file)
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -598,12 +598,24 @@ static void bcm_qspi_chip_select(struct bcm_qspi *qspi, int cs)
        qspi->curr_cs = cs;
 }
 
+static bool bcmspi_parms_did_change(const struct bcm_qspi_parms * const cur,
+                                   const struct bcm_qspi_parms * const prev)
+{
+       return (cur->speed_hz != prev->speed_hz) ||
+               (cur->mode != prev->mode) ||
+               (cur->bits_per_word != prev->bits_per_word);
+}
+
+
 /* MSPI helpers */
 static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi,
                                  const struct bcm_qspi_parms *xp)
 {
        u32 spcr, spbr = 0;
 
+       if (!bcmspi_parms_did_change(xp, &qspi->last_parms))
+               return;
+
        if (!qspi->mspi_maj_rev)
                /* legacy controller */
                spcr = MSPI_MASTER_BIT;