Hello Paweł, I would suggest dropping sentence punctuation in the patch subject line: Input: atmel_mxt_ts: Add support for optional regulators. More below... On Tue, Jul 31, 2018 at 05:18:09PM +0200, 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@xxxxxxxxx> > --- > 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 54fe190fd4bc..2cd7f6db6ba9 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 <linux/property.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 */ > @@ -310,6 +311,8 @@ 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; > @@ -3016,6 +3019,38 @@ 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); > + return error; > + } > + > + /* > + * According to maXTouch power sequencing specification, RESET line Please fix the following checkpatch issue: drivers/input/touchscreen/atmel_mxt_ts.c:3065: WARNING:LONG_LINE_COMMENT: line over 80 characters Thanks! -- Regards, George > + * must be kept low until some time after regulators come up to > + * voltage > + */ > + msleep(MXT_REGULATOR_DELAY); > + gpiod_set_value(data->reset_gpio, 1); > + msleep(MXT_RESET_INVALID_CHG); > + } > + > + return 0; > +} > + > static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id) > { > struct mxt_data *data; > @@ -3076,6 +3111,22 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id) > return error; > } > > + data->vdd_reg = devm_regulator_get(&client->dev, "vdd"); > + if (IS_ERR(data->vdd_reg)) { > + error = PTR_ERR(data->vdd_reg); > + dev_err(&client->dev, "Failed to get vdd regulator: %d\n", > + error); > + return error; > + } > + > + data->avdd_reg = devm_regulator_get(&client->dev, "avdd"); > + if (IS_ERR(data->avdd_reg)) { > + error = PTR_ERR(data->avdd_reg); > + dev_err(&client->dev, "Failed to get avdd regulator: %d\n", > + error); > + return error; > + } > + > error = devm_request_threaded_irq(&client->dev, client->irq, > NULL, mxt_interrupt, IRQF_ONESHOT, > client->name, data); > @@ -3086,11 +3137,9 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id) > > disable_irq(client->irq); > > - if (data->reset_gpio) { > - msleep(MXT_RESET_GPIO_TIME); > - gpiod_set_value(data->reset_gpio, 1); > - msleep(MXT_RESET_INVALID_CHG); > - } > + error = mxt_regulator_enable(data); > + if (error) > + return error; > > error = mxt_initialize(data); > if (error) > @@ -3116,6 +3165,10 @@ static int mxt_remove(struct i2c_client *client) > struct mxt_data *data = i2c_get_clientdata(client); > > disable_irq(data->irq); > + if (data->reset_gpio) { > + regulator_disable(data->avdd_reg); > + regulator_disable(data->vdd_reg); > + } > sysfs_remove_group(&client->dev.kobj, &mxt_attr_group); > mxt_free_input_device(data); > mxt_free_object_table(data); > -- > 2.7.4 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel