Re: [PATCH V3 2/3] ARM: clk-gate2: Add API imx_clk_gate2_exclusive for clk_gate2

From: Shawn Guo
Date: Sat Aug 09 2014 - 09:33:48 EST


On Fri, Aug 08, 2014 at 03:02:48PM +0800, Shengjiu Wang wrote:
> As some clocks are mutually exlcusive, they can't be enabled simultaneously,
> So add this new API for registering exclusive clock, the enable function will
> check if there is exclusive clock and it is not enabled, then this clock can
> be enabled, otherwise, it will return error.
>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxxxxxxxx>
> ---
> arch/arm/mach-imx/clk-gate2.c | 18 +++++++++++++++++-
> arch/arm/mach-imx/clk.h | 2 ++
> 2 files changed, 19 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/mach-imx/clk-gate2.c b/arch/arm/mach-imx/clk-gate2.c
> index 84acdfd..df64c4d 100644
> --- a/arch/arm/mach-imx/clk-gate2.c
> +++ b/arch/arm/mach-imx/clk-gate2.c
> @@ -8,7 +8,7 @@
> *
> * Gated clock implementation
> */
> -
> +#include <linux/clk-private.h>

I do not see why this header is needed.

Shawn

> #include <linux/clk-provider.h>
> #include <linux/module.h>
> #include <linux/slab.h>
> @@ -34,6 +34,7 @@ struct clk_gate2 {
> u8 flags;
> spinlock_t *lock;
> unsigned int *share_count;
> + struct clk *clk_exclusive;
> };
>
> #define to_clk_gate2(_hw) container_of(_hw, struct clk_gate2, hw)
> @@ -46,6 +47,11 @@ static int clk_gate2_enable(struct clk_hw *hw)
>
> spin_lock_irqsave(gate->lock, flags);
>
> + if (gate->clk_exclusive && __clk_is_enabled(gate->clk_exclusive)) {
> + spin_unlock_irqrestore(gate->lock, flags);
> + return -EBUSY;
> + }
> +
> if (gate->share_count && (*gate->share_count)++ > 0)
> goto out;
>
> @@ -147,3 +153,13 @@ struct clk *clk_register_gate2(struct device *dev, const char *name,
>
> return clk;
> }
> +
> +int imx_clk_gate2_exclusive(struct clk *clk1, struct clk *clk2)
> +{
> + struct clk_gate2 *gate1 = to_clk_gate2(clk1->hw);
> + struct clk_gate2 *gate2 = to_clk_gate2(clk2->hw);
> +
> + gate1->clk_exclusive = clk2;
> + gate2->clk_exclusive = clk1;
> + return 0;
> +}
> diff --git a/arch/arm/mach-imx/clk.h b/arch/arm/mach-imx/clk.h
> index d5ba76f..2b07376 100644
> --- a/arch/arm/mach-imx/clk.h
> +++ b/arch/arm/mach-imx/clk.h
> @@ -36,6 +36,8 @@ struct clk *clk_register_gate2(struct device *dev, const char *name,
> struct clk * imx_obtain_fixed_clock(
> const char *name, unsigned long rate);
>
> +int imx_clk_gate2_exclusive(struct clk *clk1, struct clk *clk2);
> +
> static inline struct clk *imx_clk_gate2(const char *name, const char *parent,
> void __iomem *reg, u8 shift)
> {
> --
> 1.7.9.5
>
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