Re: [PATCH] clk: Fix CLK_SET_RATE_GATE flag validation inclk_set_rate().

[Richard Zhao]

On Tue, May 15, 2012 at 01:43:42PM -0700, Saravana Kannan wrote:
> The clk_set_rate() code shouldn't check the clock's enable count when
> validating CLK_SET_RATE_GATE flag since the enable count could change after
> the validation. Similar to clk_set_parent(), it should instead check the
> prepare count. The prepare count should go to zero only when the end user
> expects the clock to not be enabled in the future. Since the code already
> grabs the prepare count before validation, it's not possible for prepare
> count to change after validation and by association not possible for a well
> behaving end user to enable the clock while the set rate is in progress.
> 
> Signed-off-by: Saravana Kannan <skannan@xxxxxxxxxxxxxx>
Reviewed-by: Richard Zhao <richard.zhao@xxxxxxxxxxxxx>
> ---
> Please let me know if you don't want me to directly email or CC you in my
> clock related patches. I don't want to spam anyone. Also, let me know if
> you want me add you to my standard list of people to cc in my clock
> patches.
> 
>  drivers/clk/clk.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 09b9112..f5b9d3c 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -903,7 +903,7 @@ int clk_set_rate(struct clk *clk, unsigned long rate)
>  	if (rate == clk->rate)
>  		goto out;
>  
> -	if ((clk->flags & CLK_SET_RATE_GATE) && __clk_is_enabled(clk)) {
> +	if ((clk->flags & CLK_SET_RATE_GATE) && clk->prepare_count) {
>  		ret = -EBUSY;
>  		goto out;
>  	}
> -- 
> 1.7.8.3
> 
> Sent by an employee of the Qualcomm Innovation Center, Inc.
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.
> 
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> 

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