lkml.org 
[lkml]   [2016]   [Feb]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2 2/4] regulator: lp872x: Add enable GPIO pin support
From
Date
Hi Paul,

Thanks for the patch. Please see my comments below.

On 2/6/2016 3:42 AM, Paul Kocialkowski wrote:
> LP872x regulators are made active via the EN pin, which might be hooked to a
> GPIO. This adds support for driving the GPIO high when the driver is in use.
>
> Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
> ---
> .../devicetree/bindings/regulator/lp872x.txt | 1 +
> drivers/regulator/lp872x.c | 34 ++++++++++++++++++++++
> include/linux/regulator/lp872x.h | 5 ++++
> 3 files changed, 40 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/regulator/lp872x.txt b/Documentation/devicetree/bindings/regulator/lp872x.txt
> index 7818318..ca58a68 100644
> --- a/Documentation/devicetree/bindings/regulator/lp872x.txt
> +++ b/Documentation/devicetree/bindings/regulator/lp872x.txt
> @@ -28,6 +28,7 @@ Optional properties:
> - ti,dvs-gpio: GPIO specifier for external DVS pin control of LP872x devices.
> - ti,dvs-vsel: DVS selector. 0 = SEL_V1, 1 = SEL_V2.
> - ti,dvs-state: initial DVS pin state. 0 = DVS_LOW, 1 = DVS_HIGH.
> + - enable-gpios: GPIO specifier for EN pin control of LP872x devices.
>
> Sub nodes for regulator_init_data
> LP8720 has maximum 6 nodes. (child name: ldo1 ~ 5 and buck)
> diff --git a/drivers/regulator/lp872x.c b/drivers/regulator/lp872x.c
> index 21c49d8..3899211 100644
> --- a/drivers/regulator/lp872x.c
> +++ b/drivers/regulator/lp872x.c
> @@ -15,6 +15,7 @@
> #include <linux/regmap.h>
> #include <linux/err.h>
> #include <linux/gpio.h>
> +#include <linux/delay.h>
> #include <linux/regulator/lp872x.h>
> #include <linux/regulator/driver.h>
> #include <linux/platform_device.h>
> @@ -757,6 +758,33 @@ set_default_dvs_mode:
> default_dvs_mode[lp->chipid]);
> }
>
> +static int lp872x_hw_enable(struct lp872x *lp)
> +{
> + int ret, gpio;
> +
> + if (!lp->pdata)
> + return -EINVAL;
> +
> + gpio = lp->pdata->enable_gpio;
> + if (!gpio_is_valid(gpio))
> + return 0;

It seems gpio is always 0 when it starts from DT. 'enable_gpio' is
updated in lp872x_config() but lp872x_hw_enable() is called first.

> +
> + /* Always set enable GPIO high. */
> + ret = devm_gpio_request_one(lp->dev, gpio, GPIOF_OUT_INIT_HIGH, "LP872X EN");
> + if (ret) {
> + dev_err(lp->dev, "gpio request err: %d\n", ret);
> + return ret;
> + }
> +
> + /* Each chip has a different enable delay. */
> + if (lp->chipid == LP8720)
> + usleep_range(LP8720_ENABLE_DELAY, 1.5 * LP8720_ENABLE_DELAY);
> + else
> + usleep_range(LP8725_ENABLE_DELAY, 1.5 * LP8725_ENABLE_DELAY);
> +
> + return 0;
> +}
> +
> static int lp872x_config(struct lp872x *lp)
> {
> struct lp872x_platform_data *pdata = lp->pdata;
> @@ -875,6 +903,8 @@ static struct lp872x_platform_data
> of_property_read_u8(np, "ti,dvs-state", &dvs_state);
> pdata->dvs->init_state = dvs_state ? DVS_HIGH : DVS_LOW;
>
> + pdata->enable_gpio = of_get_named_gpio(np, "enable-gpios", 0);

Please move this code to lp872x_populate_pdata_from_dt().
lp872x_hw_enable() is called prior to lp872x_config(), so enable_gpio
should be set on parsing the DT properties.

> +
> if (of_get_child_count(np) == 0)
> goto out;
>
> @@ -948,6 +978,10 @@ static int lp872x_probe(struct i2c_client *cl, const struct i2c_device_id *id)
> lp->chipid = id->driver_data;
> i2c_set_clientdata(cl, lp);
>
> + ret = lp872x_hw_enable(lp);
> + if (ret)
> + return ret;
> +
> ret = lp872x_config(lp);
> if (ret)
> return ret;
> diff --git a/include/linux/regulator/lp872x.h b/include/linux/regulator/lp872x.h
> index 132e05c..6029279 100644
> --- a/include/linux/regulator/lp872x.h
> +++ b/include/linux/regulator/lp872x.h
> @@ -18,6 +18,9 @@
>
> #define LP872X_MAX_REGULATORS 9
>
> +#define LP8720_ENABLE_DELAY 200
> +#define LP8725_ENABLE_DELAY 30000
> +
> enum lp872x_regulator_id {
> LP8720_ID_BASE,
> LP8720_ID_LDO1 = LP8720_ID_BASE,
> @@ -79,12 +82,14 @@ struct lp872x_regulator_data {
> * @update_config : if LP872X_GENERAL_CFG register is updated, set true
> * @regulator_data : platform regulator id and init data
> * @dvs : dvs data for buck voltage control
> + * @enable_gpio : gpio pin number for enable control
> */
> struct lp872x_platform_data {
> u8 general_config;
> bool update_config;
> struct lp872x_regulator_data regulator_data[LP872X_MAX_REGULATORS];
> struct lp872x_dvs *dvs;
> + int enable_gpio;
> };
>
> #endif
>

Best regards,
Milo

\
 
 \ /
  Last update: 2016-02-12 01:41    [W:0.256 / U:0.040 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site