Re: [RFC PATCH 06/11] DT: regulator: Helper routine to extract fixed_voltage_config

Grant Likely
2011-09-15T22:19:16Z

On Thu, Sep 15, 2011 at 04:52:02PM +0530, Rajendra Nayak wrote:
> The helper routine defined here (of_get_fixed_voltage_config) can
> be used to extract information about fixed regulators (which are not
> software controlable) from device tree.
>
> Add documenation about additional bindings for fixed
> regulators that can be passed through DT.
>
> Signed-off-by: Rajendra Nayak <rnayak@ti.com>
> ---
> .../devicetree/bindings/regulator/regulator.txt | 19 ++++++++++++
> drivers/of/of_regulator.c | 31 ++++++++++++++++++++
> include/linux/of_regulator.h | 7 ++++
> 3 files changed, 57 insertions(+), 0 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/regulator/regulator.txt b/Documentation/devicetree/bindings/regulator/regulator.txt
> index 001e5ce..f8c51d8 100644
> --- a/Documentation/devicetree/bindings/regulator/regulator.txt
> +++ b/Documentation/devicetree/bindings/regulator/regulator.txt
> @@ -2,6 +2,8 @@ Voltage/Current Regulators
>
> Required properties:
> - compatible: Must be "regulator";
> +or
> +- compatible: Must be "regulator-fixed"; /* For Fixed volatge regulator */

regulator-fixed should actually just be another driver binding that
uses the regulator binding.

>
> Optional properties:
> - supply-regulator: Name of the parent regulator
> @@ -24,6 +26,13 @@ Optional properties:
> - always-on: boolean, regulator should never be disabled
> - boot-on: bootloader/firmware enabled regulator
> - apply-uV: apply uV constraint if min == max
> +# For fixed voltage regulators
> +- supply-name: Name of the regulator supply
> +- microvolts: Output voltage of regulator
> +- gpio: gpio to use for enable control
> +- startup-delay: startup time in microseconds
> +- enable-high: Polarity of enable GPIO, 1 = Active High, 0 = Active low
> +- enabled-at-boot: 1 = yes, 0 = no
>
> Example:
>
> @@ -35,3 +44,13 @@ Example:
> change-voltage;
> always-on;
> };
> +
> + abc-fixedregulator {
> + compatible = "regulator-fixed";
> + supply-name = "fixed-supply";
> + microvolts = <1800000>;
> + gpio = <43>;
> + startup-delay = <70000>;
> + enable-high;
> + enabled-at-boot;
> + };
> diff --git a/drivers/of/of_regulator.c b/drivers/of/of_regulator.c
> index f01d275..4d7a49d 100644
> --- a/drivers/of/of_regulator.c
> +++ b/drivers/of/of_regulator.c
> @@ -13,6 +13,7 @@
> #include <linux/slab.h>
> #include <linux/of.h>
> #include <linux/regulator/machine.h>
> +#include <linux/regulator/fixed.h>
>
> static void of_get_regulation_constraints(struct device_node *np,
> struct regulator_init_data **init_data)
> @@ -83,3 +84,33 @@ struct regulator_init_data *of_get_regulator_init_data(struct device_node *np)
> return init_data;
> }
> EXPORT_SYMBOL(of_get_regulator_init_data);
> +
> +/**
> + * of_get_fixed_voltage_config - extract fixed_voltage_config structure info
> + * @np: Pointer to fixed-regulator device tree node
> + *
> + * Populates fixed_voltage_config structure by extracting data from device
> + * tree node, returns a pointer to the populated structure of NULL if memory
> + * alloc fails.
> + */
> +struct fixed_voltage_config *of_get_fixed_voltage_config(struct device_node *np)
> +{
> + struct fixed_voltage_config *config;
> +
> + config = kzalloc(sizeof(struct fixed_voltage_config), GFP_KERNEL);
> + if (!config)
> + return NULL;
> +
> + config->supply_name = (char *)of_get_property(np, "supply-name", NULL);
> + of_property_read_u32(np, "microvolts", &config->microvolts);
> + of_property_read_u32(np, "gpio", &config->gpio);
> + of_property_read_u32(np, "startup-delay", &config->startup_delay);
> + if (of_find_property(np, "enable-high", NULL))
> + config->enable_high = true;
> + if (of_find_property(np, "enabled-at-boot", NULL))
> + config->enabled_at_boot = true;
> + config->init_data = of_get_regulator_init_data(np);
> +
> + return config;
> +}
> +EXPORT_SYMBOL(of_get_fixed_voltage_config);
> diff --git a/include/linux/of_regulator.h b/include/linux/of_regulator.h
> index 5eb048c..39860c5 100644
> --- a/include/linux/of_regulator.h
> +++ b/include/linux/of_regulator.h
> @@ -11,12 +11,19 @@
> #if defined(CONFIG_OF_REGULATOR)
> extern struct regulator_init_data
> *of_get_regulator_init_data(struct device_node *np);
> +extern struct fixed_voltage_config
> + *of_get_fixed_voltage_config(struct device_node *np);
> #else
> static inline struct regulator_init_data
> *of_get_regulator_init_data(struct device_node *np)
> {
> return NULL;
> }
> +static inline struct fixed_voltage_config
> + *of_get_fixed_voltage_config(struct device_node *np)
> +{
> + return NULL;
> +}
> #endif /* CONFIG_OF_REGULATOR */
>
> #endif /* __LINUX_OF_REG_H */
> --
> 1.7.1
>