linux-kernel - [PATCH] atmel_lcdfb: New alternate pixel clock formula

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <1257334314-636-1-git-send-email-nicolas.ferre@atmel.com>
Date:	Wed,  4 Nov 2009 12:31:54 +0100
From:	Nicolas Ferre <nicolas.ferre@...el.com>
To:	linux-arm-kernel@...ts.infradead.org, akpm@...ux-foundation.org,
	linux-fbdev-devel@...ts.sourceforge.net
Cc:	avictor.za@...il.com, linux-kernel@...r.kernel.org,
	Nicolas Ferre <nicolas.ferre@...el.com>
Subject: [PATCH] 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.

Signed-off-by: Nicolas Ferre <nicolas.ferre@...el.com>
---
Newer 9g45 SOC will not have good pixel clock calculation without 
this fix.
Can we schedule this fix for .32-final ? 

It depends on the newly merged macros in this patch:
"at91: at91sam9g45 family: identify several chip versions"
d8951adeba05719b9efd7ce875a3294ffdbb37ea

 drivers/video/atmel_lcdfb.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 2830ffd..d5e8010 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));
 	}
-- 
1.5.6.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/