atmel_lcdfb: new alternate pixel clock formula

at91sam9g45 non ES lots have an alternate pixel clock calculation formula.
Introduce this one with condition on the cpu_is_xxxxx() macros.

Newer 9g45 SOC will not have good pixel clock calculation without this
fix.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 2830ffd72976..d5e801076d33 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -484,6 +484,7 @@ static int atmel_lcdfb_set_par(struct fb_info *info)
         unsigned long value;
         unsigned long clk_value_khz;
         unsigned long bits_per_line;
+        unsigned long pix_factor = 2;
 
         might_sleep();
 
@@ -516,20 +517,24 @@ static int atmel_lcdfb_set_par(struct fb_info *info)
         /* Now, the LCDC core... */
 
         /* Set pixel clock */
+        if (cpu_is_at91sam9g45() && !cpu_is_at91sam9g45es())
+                pix_factor = 1;
+
         clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;
 
         value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));
 
-        if (value < 2) {
+        if (value < pix_factor) {
                 dev_notice(info->device, "Bypassing pixel clock divider\n");
                 lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);
         } else {
-                value = (value / 2) - 1;
+                value = (value / pix_factor) - 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)));
+                info->var.pixclock =
+                        KHZ2PICOS(clk_value_khz / (pix_factor * (value + 1)));
                 dev_dbg(info->device, "  updated pixclk:     %lu KHz\n",
                                         PICOS2KHZ(info->var.pixclock));
         }