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

From: Laxman Dewangan
Date: Wed Jan 13 2016 - 06:50:29 EST

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);
+ }
+ }

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;