Subject: [PATCH 4/5] ARM: imx: clk-gate2: Use post decrement for share_count

From: [email-masked] (Shawn Guo)
Date: Tue, 1 Jul 2014 19:52:53 +0800

On Tue, Jul 01, 2014 at 02:55:28AM -0300, Fabio Estevam wrote:
> From: Fabio Estevam <[email-masked]>
> 
> SSI clocks use the share_count mechanism since SSI and SPDIF share the same
> clock gate bits.
> 
> When using the share_count for the SSI clock we notice that it gets disabled
> due to the usage of pre-decrement operation in the clk_gate2_disable() function.
> 
> Use the post-decrement operation so that the correct share_count is used and the
> SSI clock does not get disable when an audio file needs to be played. 
> 
> Signed-off-by: Fabio Estevam <[email-masked]>
> ---
>  arch/arm/mach-imx/clk-gate2.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-imx/clk-gate2.c b/arch/arm/mach-imx/clk-gate2.c
> index 4ba587d..463083c 100644
> --- a/arch/arm/mach-imx/clk-gate2.c
> +++ b/arch/arm/mach-imx/clk-gate2.c
> @@ -67,7 +67,7 @@ static void clk_gate2_disable(struct clk_hw *hw)
>  
>  	spin_lock_irqsave(gate->lock, flags);
>  
> -	if (gate->share_count && --(*gate->share_count) > 0)
> +	if (gate->share_count && (*gate->share_count)-- > 0)

The change makes no sense.  Let's say that clk_gate2_disable() gets
called with share_count being 1.  In this case, we should access
register to gate the clock, right?

Shawn

>  		goto out;
>  	reg = readl(gate->reg);
> -- 
> 1.8.3.2