From 99c796df94afca5256860dd4760017f1dbb3480c Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 17 Aug 2010 22:13:22 +0100 Subject: [PATCH] VIDEO: amba clcd: don't disable an already disabled clock Fix the clock enable/disable tracking in the AMBA CLCD driver so that the driver doesn't try to disable an already disabled clock, thereby causing the clock (if shared) to become unbalanced. This resolves a problem with CLCD on LPC32xx ARM platforms. Reported-by: Kevin Wells Signed-off-by: Russell King --- drivers/video/amba-clcd.c | 10 ++++++++-- include/linux/amba/clcd.h | 1 + 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c index afe21e6eb544..1c2c68356ea7 100644 --- a/drivers/video/amba-clcd.c +++ b/drivers/video/amba-clcd.c @@ -80,7 +80,10 @@ static void clcdfb_disable(struct clcd_fb *fb) /* * Disable CLCD clock source. */ - clk_disable(fb->clk); + if (fb->clk_enabled) { + fb->clk_enabled = false; + clk_disable(fb->clk); + } } static void clcdfb_enable(struct clcd_fb *fb, u32 cntl) @@ -88,7 +91,10 @@ static void clcdfb_enable(struct clcd_fb *fb, u32 cntl) /* * Enable the CLCD clock source. */ - clk_enable(fb->clk); + if (!fb->clk_enabled) { + fb->clk_enabled = true; + clk_enable(fb->clk); + } /* * Bring up by first enabling.. diff --git a/include/linux/amba/clcd.h b/include/linux/amba/clcd.h index ca16c3801a1e..be33b3affc8a 100644 --- a/include/linux/amba/clcd.h +++ b/include/linux/amba/clcd.h @@ -150,6 +150,7 @@ struct clcd_fb { u16 off_cntl; u32 clcd_cntl; u32 cmap[16]; + bool clk_enabled; }; static inline void clcdfb_decode(struct clcd_fb *fb, struct clcd_regs *regs)