Re: [PATCH] clock: max77686: Add driver for Maxim 77686 32KHz crystal oscillator

[jonghwa3.lee@samsung.com]

Hi, Arnd.
Sorry for that reply is late. I had some personal reasons so i couldn't
check e-mail all last week. I just read your comments today.

On 2012년 06월 02일 01:13, Arnd Bergmann wrote:

> On Friday 01 June 2012, Jonghwa Lee wrote:
>> +
>> +#ifdef COMMON_CONFIG_CLK
> 
> Two comments on this one:
> 
> 1. It should be CONFIG_COMMON_CLK, not COMMON_CONFIG_CLK, I suppose. The symbol
> you are testing for is never defined so your code does not even get built.
> I suppose you did not test the version you are sending ...
> 
> 2. There is no use in enclosing an entire file in #ifdef. Instead, make the Kconfig
> symbol depend on COMMON_CLK.
> 


I did build test only without #ifdef statement before upload. And i
wrote this line right before send the code. I made mistake at that time.
Anyway, I'll change this condition as you commented.

>> +#define to_max77686_clk(__name)		container_of(hw,		\
>> +					struct max77686_clk, __name)
> 
> This use of container_of() is very unusual and confusing, because the argument
> into your macro is the member of the struct, not the variable that you are basing
> from. You should not need the macro at all, so please try to remove it.
> 


Yes, i agree that this macro makes some confuse.

>> +struct max77686_clk {
>> +	struct max77686_dev *iodev;
>> +	struct clk_hw clk32khz_ap_hw;
>> +	struct clk_hw clk32khz_cp_hw;
>> +	struct clk_hw clk32khz_pmic_hw;
>> +};
>> +
>> +static struct clk *clk32khz_ap;
>> +static struct clk *clk32khz_cp;
>> +static struct clk *clk32khz_pmic;
>> +static char *max77686_clk[] = {
>> +	"32khap",
>> +	"32khcp",
>> +	"p32kh",
>> +};
> 
> With these static definitions, you can only have a single max77686 device in the
> system. Better remove these symbols.


Okay, I'll apply it.

> 
>> +static struct max77686_clk *get_max77686_clk(struct clk_hw *hw)
>> +{
>> +	struct clk *clk = hw->clk;
>> +	if (clk == clk32khz_ap)
>> +		return to_max77686_clk(clk32khz_ap_hw);
>> +	else if (clk == clk32khz_cp)
>> +		return to_max77686_clk(clk32khz_cp_hw);
>> +	else if (clk == clk32khz_pmic)
>> +		return to_max77686_clk(clk32khz_pmic_hw);
>> +	else
>> +		return NULL;
>> +}
> 
> I can only assume that you meant this to be
> 
> struct max77686_clk {
> 	struct max77686_dev *iodev;
> 	u32 mask;
> 	struct clk_hw hw;
> };
> static struct max77686_clk *get_max77686_clk(struct clk_hw *hw)
> {
> 	return container_of(hw, struct max77686_clk, hw)->iodev;
> }
> 
> You probably misunderstood the person who was suggesting you use
> container_of(). Note that this function is so simple that you
> probably don't even need it: just open-code the container_of.
>


I think to_max77686_clk macro makes you uncomfortable, I'll modify them
with considering your comments. And your get_max77668_clk() return wrong
type pointer since it has to return struct max77696_clk pointer.

 

Thanks.