[PATCH] atmel_lcdfb: fix pixclok divider calculation

From: Nicolas Ferre
Date: Tue May 06 2008 - 12:34:50 EST


Fix divider calculation and allow CLKVAL = 0 (divisor 2)

It was not possible to get the clock value 0 (divisor 2) because the test "<=0" force the BYPASS bit to be activated instead.

Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
---
Thanks a lot to Jan, Per, Roel and Haavard for sending me
similar patches.

drivers/video/atmel_lcdfb.c | 7 +++----
1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -441,13 +441,12 @@ static int atmel_lcdfb_set_par(struct fb_info *info)

value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));

- value = (value / 2) - 1;
- dev_dbg(info->device, " * programming CLKVAL = 0x%08lx\n", value);
-
- if (value <= 0) {
+ if (value < 2) {
dev_notice(info->device, "Bypassing pixel clock divider\n");
lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
} else {
+ value = (value / 2) - 1;
+ dev_dbg(info->device, " * programming CLKVAL = 0x%08lx\n", value);
lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, value << ATMEL_LCDC_CLKVAL_OFFSET);
info->var.pixclock = KHZ2PICOS(clk_value_khz / (2 * (value + 1)));
dev_dbg(info->device, " updated pixclk: %lu KHz\n",

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