[PATCH] add clock debug information for imx51 babbage

[arnaud.patard@rtp-net.org (Arnaud Patard (Rtp))]

Yong Shen <yong.shen@linaro.org> writes:

> Hi there,
>
> This patch makes BSP development easier, since it displays the whole
> clock information in tree-like manner. The final goal is to make it a
> part of common clock framework, but so far this goal depends on other
> unfinished work.
>
> PS: Due to the firewall problem, I send out patch this way. Please
> give comments inline and use attached patch for testing.
>
>>From a856d68c53cf91b3fa30a7742057f7afdaf77482 Mon Sep 17 00:00:00 2001
> From: Yong Shen <yong.shen@linaro.org>
> Date: Wed, 1 Dec 2010 19:18:34 +0800
> Subject: [PATCH] add clock debug information for imx51 babbage

why "imx51 babbage" ? I guess it should be working for all imx51/53
boards

>
> Add code to expose a tree-like clock debug information in sysfs.
>
> Signed-off-by: Yong Shen <yong.shen@linaro.org>

[...]


> @@ -842,8 +871,10 @@ static struct clk emi_slow_clk = {
>  	.get_rate = clk_emi_slow_get_rate,
>  };
>
> +
>  #define DEFINE_CLOCK_CCGR(name, i, er, es, pfx, p, s)	\
>  	static struct clk name = {			\
> +		__INIT_CLK_DEBUG(name)			\

why not ".name = name," no matter of CONFIG_CLK_DEBUG value ?

>  		.id		= i,			\
>  		.enable_reg	= er,			\
>  		.enable_shift	= es,			\
> @@ -859,6 +890,7 @@ static struct clk emi_slow_clk = {
>
>  #define DEFINE_CLOCK_MAX(name, i, er, es, pfx, p, s)	\
>  	static struct clk name = {			\
> +		__INIT_CLK_DEBUG(name)			\
>  		.id		= i,			\
>  		.enable_reg	= er,			\
>  		.enable_shift	= es,			\
> @@ -937,6 +969,7 @@ CLK_GET_RATE(uart, 1, UART)

[...]

> +struct preinit_clk {
> +	struct list_head list;
> +	struct clk *clk;
> +};
> +static LIST_HEAD(preinit_clks);
> +static DEFINE_MUTEX(preinit_lock);
> +static int init_done;
> +
> +void clk_debug_register(struct clk *clk)
> +{
> +	int err;
> +	struct clk *pa;
> +
> +	if (init_done) {

is there a reason for not using debugfs_initialized() directly ?

> +		pa = clk_get_parent(clk);
> +
> +		if (pa && !IS_ERR(pa) && !pa->dentry)
> +			clk_debug_register(pa);
> +
> +		if (!clk->dentry) {
> +			err = clk_debug_register_one(clk);
> +			if (err)
> +				return;
> +		}
> +	} else {
> +		struct preinit_clk *p;
> +		mutex_lock(&preinit_lock);
> +		p = kmalloc(sizeof(*p), GFP_KERNEL);
> +		if (!p)
> +			goto unlock;
> +		p->clk = clk;
> +		list_add(&p->list, &preinit_clks);
> +unlock:
> +		mutex_unlock(&preinit_lock);
> +	}
> +}
> +EXPORT_SYMBOL_GPL(clk_debug_register);
> +
> +static int __init clk_debugfs_init(void)
> +{
> +	struct preinit_clk *pclk, *tmp;
> +
> +	if (debugfs_initialized())
> +		init_done = 1;
> +
> +	list_for_each_entry(pclk, &preinit_clks, list) {
> +		clk_debug_register(pclk->clk);
> +	}
> +
> +	list_for_each_entry_safe(pclk, tmp, &preinit_clks, list) {
> +		list_del(&pclk->list);
> +		kfree(pclk);
> +	}
> +	return 0;
> +}
> +late_initcall(clk_debugfs_init);
> +#endif
> diff --git a/arch/arm/plat-mxc/include/mach/clock.h
> b/arch/arm/plat-mxc/include/mach/clock.h
> index 753a598..fb0e0bd 100644
> --- a/arch/arm/plat-mxc/include/mach/clock.h
> +++ b/arch/arm/plat-mxc/include/mach/clock.h
> @@ -23,9 +23,14 @@
>  #ifndef __ASSEMBLY__
>  #include <linux/list.h>
>
> +#define CLK_NAME_LEN 32
>  struct module;
>
>  struct clk {
> +#ifdef CONFIG_CLK_DEBUG
> +	char name[CLK_NAME_LEN];
> +	struct dentry           *dentry;
> +#endif

Do we really need the #ifdef here ?

Arnaud