Input: zforce - add regulator handling
It's possible that the controller has an individually switchable power supply.
Therefore add support to control a supplying regulator.
As this is not always the case, the regulator is requested as optional.
Signed-off-by: Heiko Stuebner <heiko.stuebner@bq.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/touchscreen/zforce_ts.c b/drivers/input/touchscreen/zforce_ts.c
index feea85b..8ba48f5 100644
--- a/drivers/input/touchscreen/zforce_ts.c
+++ b/drivers/input/touchscreen/zforce_ts.c
@@ -29,6 +29,8 @@
#include <linux/sysfs.h>
#include <linux/input/mt.h>
#include <linux/platform_data/zforce_ts.h>
+#include <linux/regulator/consumer.h>
+#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
@@ -117,6 +119,8 @@
const struct zforce_ts_platdata *pdata;
char phys[32];
+ struct regulator *reg_vdd;
+
bool suspending;
bool suspended;
bool boot_complete;
@@ -690,6 +694,11 @@
struct zforce_ts *ts = data;
gpio_set_value(ts->pdata->gpio_rst, 0);
+
+ udelay(10);
+
+ if (!IS_ERR(ts->reg_vdd))
+ regulator_disable(ts->reg_vdd);
}
static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
@@ -765,10 +774,32 @@
return ret;
}
+ ts->reg_vdd = devm_regulator_get_optional(&client->dev, "vdd");
+ if (IS_ERR(ts->reg_vdd)) {
+ ret = PTR_ERR(ts->reg_vdd);
+ if (ret == -EPROBE_DEFER)
+ return ret;
+ } else {
+ ret = regulator_enable(ts->reg_vdd);
+ if (ret)
+ return ret;
+
+ /*
+ * according to datasheet add 100us grace time after regular
+ * regulator enable delay.
+ */
+ udelay(100);
+ }
+
ret = devm_add_action(&client->dev, zforce_reset, ts);
if (ret) {
dev_err(&client->dev, "failed to register reset action, %d\n",
ret);
+
+ /* hereafter the regulator will be disabled by the action */
+ if (!IS_ERR(ts->reg_vdd))
+ regulator_disable(ts->reg_vdd);
+
return ret;
}