Re: [PATCH v4 1/3] Input: atmel_mxt_ts: Add support for optional regulators

Dmitry Torokhov
2018-12-09T04:26:12Z

On Fri, Dec 07, 2018 at 03:28:55PM +0100, Paweł Chmiel wrote:
> This patch adds optional regulators, which can be used to power
> up touchscreen. After enabling regulators, we need to wait 150msec.
> This value is taken from official driver.
>
> It was tested on Samsung Galaxy i9000 (based on Samsung S5PV210 SOC).
>
> Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
> ---
> Changes from v3:
> - Fix checkpatch issues
> - Drop sentence punctuation from subject of one of patches
>
> Changes from v2:
> - Move code enabling regulators into separate method,
> to make code more readable.
>
> Changes from v1:
> - Enable regulators only if reset_gpio is present.
> - Switch from devm_regulator_get_optional to devm_regulator_get
> ---
> drivers/input/touchscreen/atmel_mxt_ts.c | 65 +++++++++++++++++++++---
> 1 file changed, 59 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> index d3aacd534e9c..1dc8ad0da5af 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -27,6 +27,7 @@
> #include <linux/interrupt.h>
> #include <linux/of.h>
> #include <linux/property.h>
> +#include <linux/regulator/consumer.h>
> #include <linux/slab.h>
> #include <linux/gpio/consumer.h>
> #include <asm/unaligned.h>
> @@ -194,10 +195,10 @@ enum t100_type {
>
> /* Delay times */
> #define MXT_BACKUP_TIME 50 /* msec */
> -#define MXT_RESET_GPIO_TIME 20 /* msec */
> #define MXT_RESET_INVALID_CHG 100 /* msec */
> #define MXT_RESET_TIME 200 /* msec */
> #define MXT_RESET_TIMEOUT 3000 /* msec */
> +#define MXT_REGULATOR_DELAY 150 /* msec */
> #define MXT_CRC_TIMEOUT 1000 /* msec */
> #define MXT_FW_RESET_TIME 3000 /* msec */
> #define MXT_FW_CHG_TIMEOUT 300 /* msec */
> @@ -323,6 +324,8 @@ struct mxt_data {
> struct t7_config t7_cfg;
> struct mxt_dbg dbg;
> struct gpio_desc *reset_gpio;
> + struct regulator *vdd_reg;
> + struct regulator *avdd_reg;
>
> /* Cached parameters from object table */
> u16 T5_address;
> @@ -3038,6 +3041,38 @@ static const struct dmi_system_id chromebook_T9_suspend_dmi[] = {
> { }
> };
>
> +static int mxt_regulator_enable(struct mxt_data *data)
> +{
> + int error;
> +
> + if (data->reset_gpio) {
> + error = regulator_enable(data->vdd_reg);
> + if (error) {
> + dev_err(&data->client->dev,
> + "Failed to enable vdd regulator: %d\n", error);
> + return error;
> + }
> +
> + error = regulator_enable(data->avdd_reg);
> + if (error) {
> + dev_err(&data->client->dev,
> + "Failed to enable avdd regulator: %d\n", error);

This leaves vdd regulator enabled.

Thanks.

--
Dmitry