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authorIngo Molnar <mingo@elte.hu>2009-08-24 12:25:44 +0200
committerIngo Molnar <mingo@elte.hu>2009-08-24 12:25:54 +0200
commit5f9ece02401116b29eb04396b99ea092acb75dd8 (patch)
treee10386e2dc63c275646b4eb0bed857da7bf86c6a /drivers/spi/spi_s3c24xx.c
parent9f51e24ee8b5a1595b6a5ac0c2be278a16488e75 (diff)
parent422bef879e84104fee6dc68ded0e371dbeb5f88e (diff)
downloadolio-linux-3.10-5f9ece02401116b29eb04396b99ea092acb75dd8.tar.xz
olio-linux-3.10-5f9ece02401116b29eb04396b99ea092acb75dd8.zip
Merge commit 'v2.6.31-rc7' into x86/cleanups
Merge reason: we were on -rc1 before - go up to -rc7 Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/spi/spi_s3c24xx.c')
-rw-r--r--drivers/spi/spi_s3c24xx.c23
1 files changed, 13 insertions, 10 deletions
diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c
index e0d44af4745..3f3119d760d 100644
--- a/drivers/spi/spi_s3c24xx.c
+++ b/drivers/spi/spi_s3c24xx.c
@@ -111,29 +111,32 @@ static int s3c24xx_spi_setupxfer(struct spi_device *spi,
unsigned int bpw;
unsigned int hz;
unsigned int div;
+ unsigned long clk;
bpw = t ? t->bits_per_word : spi->bits_per_word;
hz = t ? t->speed_hz : spi->max_speed_hz;
+ if (!bpw)
+ bpw = 8;
+
+ if (!hz)
+ hz = spi->max_speed_hz;
+
if (bpw != 8) {
dev_err(&spi->dev, "invalid bits-per-word (%d)\n", bpw);
return -EINVAL;
}
- div = clk_get_rate(hw->clk) / hz;
-
- /* is clk = pclk / (2 * (pre+1)), or is it
- * clk = (pclk * 2) / ( pre + 1) */
-
- div /= 2;
-
- if (div > 0)
- div -= 1;
+ clk = clk_get_rate(hw->clk);
+ div = DIV_ROUND_UP(clk, hz * 2) - 1;
if (div > 255)
div = 255;
- dev_dbg(&spi->dev, "setting pre-scaler to %d (hz %d)\n", div, hz);
+ dev_dbg(&spi->dev, "setting pre-scaler to %d (wanted %d, got %ld)\n",
+ div, hz, clk / (2 * (div + 1)));
+
+
writeb(div, hw->regs + S3C2410_SPPRE);
spin_lock(&hw->bitbang.lock);