Commit 53604dbe authored by Peter Korsgaard's avatar Peter Korsgaard Committed by Linus Torvalds

spi_mpc83xx: fix clockrate calculation for low speed

Commit a61f5345 (spi_mpc83xx clockrate fixes) broke clockrate calculation
for low speeds.  SPMODE_DIV16 should be set if the divider is higher than
64, not only if the divider gets clipped to 1024.

Furthermore, the clipping check was off by a factor 16 as well.
Signed-off-by: default avatarPeter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d7a3e495
...@@ -267,17 +267,14 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) ...@@ -267,17 +267,14 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
cs->hw_mode |= SPMODE_LEN(bits_per_word); cs->hw_mode |= SPMODE_LEN(bits_per_word);
if ((mpc83xx_spi->spibrg / hz) > 64) { if ((mpc83xx_spi->spibrg / hz) > 64) {
pm = mpc83xx_spi->spibrg / (hz * 64);
if (pm > 16) {
cs->hw_mode |= SPMODE_DIV16; cs->hw_mode |= SPMODE_DIV16;
pm /= 16; pm = mpc83xx_spi->spibrg / (hz * 64);
if (pm > 16) { if (pm > 16) {
dev_err(&spi->dev, "Requested speed is too " dev_err(&spi->dev, "Requested speed is too "
"low: %d Hz. Will use %d Hz instead.\n", "low: %d Hz. Will use %d Hz instead.\n",
hz, mpc83xx_spi->spibrg / 1024); hz, mpc83xx_spi->spibrg / 1024);
pm = 16; pm = 16;
} }
}
} else } else
pm = mpc83xx_spi->spibrg / (hz * 4); pm = mpc83xx_spi->spibrg / (hz * 4);
if (pm) if (pm)
......
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