Re: [PATCH] regulator: Simplify MAX8997_REG_BUCK1DVS/MAX8997_REG_BUCK2DVS/MAX8997_REG_BUCK5DVS macros

[MyungJoo Ham <myungjoo.ham@samsung.com>]

Hello Axel,

On Mon, May 16, 2011 at 5:05 PM, Axel Lin <axel.lin@gmail.com> wrote:
> Hi MyungJoo,
>
> 2011/5/16 함명주 <myungjoo.ham@samsung.com>:
>> Hello,
>>
>>> Sender : Axel Lin<axel.lin@gmail.com>
>>> Date : 2011-05-16 15:52 (GMT+09:00)
>>> Title : [PATCH] regulator: Simplify MAX8997_REG_BUCK1DVS/MAX8997_REG_BUCK2DVS/MAX8997_REG_BUCK5DVS macros
>>>
>>> Looks like the original macro implementation assumes the caller pass the
>>> parameter starting from 1.
>>> Since now we have +1 operation from all the caller, it would be easier to
>>> assume the caller pass the parameter starting from 0.
>>> Then we can simplify the +1 operation from the caller and then -1 operation
>>> in the macro implementation.
>>>
>>> I think this change also improves readability.
>>>
>>> Signed-off-by: Axel Lin
>>
>> Well, I'd rather just change the for loop statement for your purpose, which I also agree.
>>
>> The reason I've used BUCKxDVS1 as the starting point is because of the register names; register names of BUCKxDVS starts from 1, not from 0.
>
> Ok. I got your point for the implementation.
>
>> Thus, in order to maintain the consistency between the code and the chip manual, I'd rather not change that part, but change like this:
>>
>> ---
>> diff --git a/drivers/regulator/max8997.c b/drivers/regulator/max8997.c
>> index b1c1444..aad85e4 100644
>> --- a/drivers/regulator/max8997.c
>> +++ b/drivers/regulator/max8997.c
>> @@ -1031,12 +1031,12 @@ static __devinit int max8997_pmic_probe(struct platform_device *pdev)
>>        }
>>
>>        /* For the safety, set max voltage before setting up */
>> -       for (i = 0; i < 8; i++) {
>> -               max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS(i + 1),
>> +       for (i = 1; i <= 8; i++) {
>> +               max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS(i),
>>                                max_buck1, 0x3f);
>> -               max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS(i + 1),
>> +               max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS(i),
>>                                max_buck2, 0x3f);
>> -               max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS(i + 1),
>> +               max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS(i),
>>                                max_buck5, 0x3f);
>>        }
>>
>> --
>> 1.7.4.1
>>
>> How about this one?
>>
> But it doesn't apply for below case because max8997->buck1_vol[i] is
> start from 0.
>
>
>        for (i = 0; i < 8; i++) {
>                max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS(i),
>                                max8997->buck1_vol[i],
>                                0x3f);
>
> Maybe consider to remove the macro may make things simpler.
> If you agree, I'll send a v2.

Yes, that looks just fine to me.

Thank you.


- MyungJoo

>
> diff --git a/drivers/regulator/max8997.c b/drivers/regulator/max8997.c
> index b1c1444..10d5a1d 100644
> --- a/drivers/regulator/max8997.c
> +++ b/drivers/regulator/max8997.c
> @@ -1032,11 +1032,11 @@ static __devinit int max8997_pmic_probe(struct
> platform_device *pdev)
>
>        /* For the safety, set max voltage before setting up */
>        for (i = 0; i < 8; i++) {
> -               max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS(i + 1),
> +               max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS1 + i,
>                                max_buck1, 0x3f);
> -               max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS(i + 1),
> +               max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS1 + i,
>                                max_buck2, 0x3f);
> -               max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS(i + 1),
> +               max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS1 + i,
>                                max_buck5, 0x3f);
>        }
>
> @@ -1113,13 +1113,13 @@ static __devinit int max8997_pmic_probe(struct
> platform_device *pdev)
>
>        /* Initialize all the DVS related BUCK registers */
>        for (i = 0; i < 8; i++) {
> -               max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS(i + 1),
> +               max8997_update_reg(i2c, MAX8997_REG_BUCK1DVS1 + i,
>                                max8997->buck1_vol[i],
>                                0x3f);
> -               max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS(i + 1),
> +               max8997_update_reg(i2c, MAX8997_REG_BUCK2DVS1 + i,
>                                max8997->buck2_vol[i],
>                                0x3f);
> -               max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS(i + 1),
> +               max8997_update_reg(i2c, MAX8997_REG_BUCK5DVS1 + i,
>                                max8997->buck5_vol[i],
>                                0x3f);
>        }
> diff --git a/include/linux/mfd/max8997-private.h
> b/include/linux/mfd/max8997-private.h
> index 69d1010..5ff2400 100644
> --- a/include/linux/mfd/max8997-private.h
> +++ b/include/linux/mfd/max8997-private.h
> @@ -311,10 +311,6 @@ enum max8997_irq {
>        MAX8997_IRQ_NR,
>  };
>
> -#define MAX8997_REG_BUCK1DVS(x)        (MAX8997_REG_BUCK1DVS1 + (x) - 1)
> -#define MAX8997_REG_BUCK2DVS(x)        (MAX8997_REG_BUCK2DVS1 + (x) - 1)
> -#define MAX8997_REG_BUCK5DVS(x)        (MAX8997_REG_BUCK5DVS1 + (x) - 1)
> -
>  #define MAX8997_NUM_GPIO       12
>  struct max8997_dev {
>        struct device *dev;
>
>
> Regards,
> Axel
>



-- 
MyungJoo Ham (함명주), Ph.D.
Mobile Software Platform Lab,
Digital Media and Communications (DMC) Business
Samsung Electronics
cell: 82-10-6714-2858