spi/fsl-espi: make the clock computation easier to read

The -1 +1 thingy should probably do what DIV_ROUND_UP does. The 4 is 2
the  "platform_clock => sysclock" and 2 from the computation part. The 64
is the same 4 times 16.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Sebastian Andrzej Siewior 2012-03-15 18:42:31 +01:00 committed by Grant Likely
parent bb9c5687e8
commit 35faa55cff

View file

@ -180,7 +180,7 @@ static int fsl_espi_setup_transfer(struct spi_device *spi,
if ((mpc8xxx_spi->spibrg / hz) > 64) {
cs->hw_mode |= CSMODE_DIV16;
pm = (mpc8xxx_spi->spibrg - 1) / (hz * 64) + 1;
pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 16 * 4);
WARN_ONCE(pm > 16, "%s: Requested speed is too low: %d Hz. "
"Will use %d Hz instead.\n", dev_name(&spi->dev),
@ -188,7 +188,7 @@ static int fsl_espi_setup_transfer(struct spi_device *spi,
if (pm > 16)
pm = 16;
} else {
pm = (mpc8xxx_spi->spibrg - 1) / (hz * 4) + 1;
pm = DIV_ROUND_UP(mpc8xxx_spi->spibrg, hz * 4);
}
if (pm)
pm--;