Re: [PATCH V2 6/6] regulator: max77620: add regulator driver for max77620/max20024

[Laxman Dewangan <ldewangan@nvidia.com>]

On Wednesday 13 January 2016 06:58 AM, Krzysztof Kozlowski wrote:
> On 12.01.2016 18:17, Laxman Dewangan wrote:
> +
> +	ret = of_regulator_match(&pdev->dev, np, max77620_regulator_matches,
> +			ARRAY_SIZE(max77620_regulator_matches));
> Why not using 'regulators_node' and getting rid of this and some code
> below? If you need to parse custom regulator properties use 'of_parse_cb'.
>

Yaah, this is something new and I think Mark also wanted to do this 
cleanup on his comment. I did not understand it previously. Looks cool now.

However, I have requirement to configure PMIC with some inital setting 
based on init_data (parsed) before regulator registration happened. Once 
I move to this new mecahinsm, the inti_data parsing and regulator init 
happen in the same function. So I need to have one callback from 
regulator_register to driver.
Something below. This will do the pre configuration before 
regulator_register happena dn machine constraint sets.

I can not use the init_data->regulator_init() as I need to have the init 
data passed to the driver.

Created sample patch below.

ldewangan@ldewanganubuntu-System-Product-Name:~/upstream/linux-next/linux-next/drivers/regulator$ 
git diff core.c ../../include/linux/regulator/driver.h
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 3308c6b..aa2ca20 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -3899,6 +3899,17 @@ regulator_register(const struct regulator_desc 
*regulator_desc,
                 rdev->dev.of_node = of_node_get(config->of_node);
         }

+       if (init_data && regulator_desc->pre_register_init) {
+               ret = regulator_desc->pre_register_init(regulator_desc,
+                                       config, init_data);
+               if (ret < 0) {
+                       dev_err(dev, "Pre register failed: %d\n", ret);
+                       kfree(rdev);
+                       kfree(config);
+                       return ERR_PTR(ret);
+               }
+       }
+
         mutex_lock(&regulator_list_mutex);

         mutex_init(&rdev->mutex);
diff --git a/include/linux/regulator/driver.h 
b/include/linux/regulator/driver.h
index 16ac9e1..fd1d989 100644
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -280,6 +280,9 @@ struct regulator_desc {
         int (*of_parse_cb)(struct device_node *,
                             const struct regulator_desc *,
                             struct regulator_config *);
+       int (*pre_register_init)(const struct regulator_desc *,
+                       struct regulator_config *,
+                       struct regulator_init_data *);
         int id;
         bool continuous_voltage_range;
         unsigned n_voltages;