Hi Mark,
On Thu, May 10, 2012 at 12:17 AM, Mark Brown
<broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> On Wed, May 09, 2012 at 09:54:55PM +0530, Yadwinder Singh wrote:
>
>> +/* Voltage maps in mV */
>> +static const struct voltage_map_desc ldo_voltage_map_desc = {
>> + .min = 800, .max = 3950, .step = 50, .n_bits = 6,
>> +}; /* LDO3 ~ 5, 9 ~ 14, 16 ~ 26 */
>
> Hrm, funnily enough I was just thinking about factoring this stuff out
> into the core after a conversation with Graeme Gregory the other week.
> Let's do that...
>
>> + [MAX77686_EN32KHZ_AP] = NULL,
>> + [MAX77686_EN32KHZ_CP] = NULL,
>
> Now that the generic clock API is in mainline these should be moved over
> to use it.
>
>> +static int max77686_get_voltage_unit(int rid)
>> +{
>> + int unit = 0;
>> +
>> + switch (rid) {
>> + case MAX77686_BUCK2...MAX77686_BUCK4:
>> + unit = 1; /* BUCK2,3,4 is uV */
>> + break;
>> + default:
>> + unit = 1000;
>
> Why not just list everything in uV?
>
>> +static int max77686_get_voltage(struct regulator_dev *rdev)
>> +{
>
> Implement get_voltage_sel().
>
>> +static inline int max77686_get_voltage_proper_val(const struct voltage_map_desc
>> + *desc, int min_vol,
>> + int max_vol)
>> +{
>> + int i = 0;
>> +
>> + if (desc == NULL)
>> + return -EINVAL;
>> +
>> + if (max_vol < desc->min || min_vol > desc->max)
>> + return -EINVAL;
>> +
>> + while (desc->min + desc->step * i < min_vol &&
>> + desc->min + desc->step * i < desc->max)
>> + i++;
>
> Why are you iterating here? Calculate! Though like I say let's factor
> this out anyway.
>
>> + if (rid == MAX77686_BUCK2 || rid == MAX77686_BUCK3 ||
>> + rid == MAX77686_BUCK4) {
>> + /* If the voltage is increasing */
>> + if (org < i)
>> + udelay(DIV_ROUND_UP(desc->step * (i - org),
>> + ramp[max77686->ramp_delay]));
>> + }
>
> Don't do this, implement set_voltage_time_sel().
>
>> + .enable = max77686_reg_enable,
>> + .disable = max77686_reg_disable,
>> + .set_suspend_enable = max77686_reg_enable,
>> + .set_suspend_disable = max77686_reg_disable,
>
> You've got the same ops for suspend and non-suspend cases here, this is
> clearly buggy.
>
>> +/* count the number of regulators to be supported in pmic */
>> + pdata->num_regulators = 0;
>
> Coding style.
>
>> + if (iodev->dev->of_node) {
>> + ret = max77686_pmic_dt_parse_pdata(iodev, pdata);
>> + if (ret)
>> + return ret;
>
> This ought to use of_regulator_match().
>
While using it I am seeing that though it reduces few lines of code in
our driver , it adds a huge array(of_regulator_match[])in which we
have to populate the strings(name) which we already have in
regulator_desc[ ], Isn't it overhead ?
>> + }
>> +
>> + if (!pdata) {
>> + dev_err(&pdev->dev, "platform data not found\n");
>> + return -ENODEV;
>> + }
>
> This should be totally fine.
>
>> + max77686 = kzalloc(sizeof(struct max77686_data), GFP_KERNEL);
>> + if (!max77686)
>> + return -ENOMEM;
>
> devm_kzalloc().
>
>> + if (pdata->ramp_delay) {
>> + max77686->ramp_delay = pdata->ramp_delay;
>> + max77686_update_reg(i2c, MAX77686_REG_BUCK2CTRL1,
>> + RAMP_VALUE, RAMP_MASK);
>
> This appears not to actually use the value passed in as platform_data.
>
>> +
>> + for (i = 0; i < pdata->num_regulators; i++) {
>> + const struct voltage_map_desc *desc;
>> + int id = pdata->regulators[i].id;
>> +
>> + desc = reg_voltage_map[id];
>> + if (desc)
>> + regulators[id].n_voltages =
>> + (desc->max - desc->min) / desc->step + 1;
>> +
>> + rdev[i] = regulator_register(®ulators[id], max77686->dev,
>> + pdata->regulators[i].initdata,
>> + max77686, NULL);
>
> No, you should unconditionally register all regulators the device
> physically has. This is useful for debug and simplifies the code.
>
If we have to use only 2 or 3 regulators on our board out off 36 or
lets take a case if our chip supports 50/100 regulators, I think i
will a overhead to register all unused regulators as well as
populating all the regulators in DT or platform data.
Regards,
Yadwinder.
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