Commit 53604dbe authored Sep 13, 2008 by Peter Korsgaard Committed by Linus Torvalds Sep 13, 2008

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: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent d7a3e495

drivers/spi/spi_mpc83xx.c

+5 −8

Original line number	Diff line number	Diff line
		@@ -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);

		if ((mpc83xx_spi->spibrg / hz) > 64) {
		pm = mpc83xx_spi->spibrg / (hz * 64);
		if (pm > 16) {
		cs->hw_mode \|= SPMODE_DIV16;
		pm /= 16;
		pm = mpc83xx_spi->spibrg / (hz * 64);
		if (pm > 16) {
		dev_err(&spi->dev, "Requested speed is too "
		"low: %d Hz. Will use %d Hz instead.\n",
		hz, mpc83xx_spi->spibrg / 1024);
		pm = 16;
		}
		}
		} else
		pm = mpc83xx_spi->spibrg / (hz * 4);
		if (pm)