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path: root/drivers/input/touchscreen/atmel_mxt_ts.c
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Diffstat (limited to 'drivers/input/touchscreen/atmel_mxt_ts.c')
-rw-r--r--drivers/input/touchscreen/atmel_mxt_ts.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 383a848eb601..5ed23689047b 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -31,6 +31,7 @@
#include <media/v4l2-ioctl.h>
#include <media/videobuf2-v4l2.h>
#include <media/videobuf2-vmalloc.h>
+#include <dt-bindings/input/atmel-maxtouch.h>
/* Firmware files */
#define MXT_FW_NAME "maxtouch.fw"
@@ -199,6 +200,7 @@ enum t100_type {
#define MXT_CRC_TIMEOUT 1000 /* msec */
#define MXT_FW_RESET_TIME 3000 /* msec */
#define MXT_FW_CHG_TIMEOUT 300 /* msec */
+#define MXT_WAKEUP_TIME 25 /* msec */
/* Command to unlock bootloader */
#define MXT_UNLOCK_CMD_MSB 0xaa
@@ -312,6 +314,7 @@ struct mxt_data {
struct mxt_dbg dbg;
struct regulator_bulk_data regulators[2];
struct gpio_desc *reset_gpio;
+ struct gpio_desc *wake_gpio;
bool use_retrigen_workaround;
/* Cached parameters from object table */
@@ -342,6 +345,8 @@ struct mxt_data {
unsigned int t19_num_keys;
enum mxt_suspend_mode suspend_mode;
+
+ u32 wakeup_method;
};
struct mxt_vb2_buffer {
@@ -621,10 +626,42 @@ static int mxt_send_bootloader_cmd(struct mxt_data *data, bool unlock)
return mxt_bootloader_write(data, buf, sizeof(buf));
}
+static bool mxt_wakeup_toggle(struct i2c_client *client,
+ bool wake_up, bool in_i2c)
+{
+ struct mxt_data *data = i2c_get_clientdata(client);
+
+ switch (data->wakeup_method) {
+ case ATMEL_MXT_WAKEUP_I2C_SCL:
+ if (!in_i2c)
+ return false;
+ break;
+
+ case ATMEL_MXT_WAKEUP_GPIO:
+ if (in_i2c)
+ return false;
+
+ gpiod_set_value(data->wake_gpio, wake_up);
+ break;
+
+ default:
+ return false;
+ }
+
+ if (wake_up) {
+ dev_dbg(&client->dev, "waking up controller\n");
+
+ msleep(MXT_WAKEUP_TIME);
+ }
+
+ return true;
+}
+
static int __mxt_read_reg(struct i2c_client *client,
u16 reg, u16 len, void *val)
{
struct i2c_msg xfer[2];
+ bool retried = false;
u8 buf[2];
int ret;
@@ -643,9 +680,13 @@ static int __mxt_read_reg(struct i2c_client *client,
xfer[1].len = len;
xfer[1].buf = val;
+retry:
ret = i2c_transfer(client->adapter, xfer, 2);
if (ret == 2) {
ret = 0;
+ } else if (!retried && mxt_wakeup_toggle(client, true, true)) {
+ retried = true;
+ goto retry;
} else {
if (ret >= 0)
ret = -EIO;
@@ -659,6 +700,7 @@ static int __mxt_read_reg(struct i2c_client *client,
static int __mxt_write_reg(struct i2c_client *client, u16 reg, u16 len,
const void *val)
{
+ bool retried = false;
u8 *buf;
size_t count;
int ret;
@@ -672,9 +714,13 @@ static int __mxt_write_reg(struct i2c_client *client, u16 reg, u16 len,
buf[1] = (reg >> 8) & 0xff;
memcpy(&buf[2], val, len);
+retry:
ret = i2c_master_send(client, buf, count);
if (ret == count) {
ret = 0;
+ } else if (!retried && mxt_wakeup_toggle(client, true, true)) {
+ retried = true;
+ goto retry;
} else {
if (ret >= 0)
ret = -EIO;
@@ -2975,6 +3021,8 @@ static const struct attribute_group mxt_attr_group = {
static void mxt_start(struct mxt_data *data)
{
+ mxt_wakeup_toggle(data->client, true, false);
+
switch (data->suspend_mode) {
case MXT_SUSPEND_T9_CTRL:
mxt_soft_reset(data);
@@ -3009,6 +3057,8 @@ static void mxt_stop(struct mxt_data *data)
mxt_set_t7_power_cfg(data, MXT_POWER_CFG_DEEPSLEEP);
break;
}
+
+ mxt_wakeup_toggle(data->client, false, false);
}
static int mxt_input_open(struct input_dev *dev)
@@ -3155,6 +3205,15 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
return error;
}
+ /* Request the WAKE line as asserted so we go out of sleep */
+ data->wake_gpio = devm_gpiod_get_optional(&client->dev,
+ "wake", GPIOD_OUT_HIGH);
+ if (IS_ERR(data->wake_gpio)) {
+ error = PTR_ERR(data->wake_gpio);
+ dev_err(&client->dev, "Failed to get wake gpio: %d\n", error);
+ return error;
+ }
+
error = devm_request_threaded_irq(&client->dev, client->irq,
NULL, mxt_interrupt, IRQF_ONESHOT,
client->name, data);
@@ -3185,6 +3244,25 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
msleep(MXT_RESET_INVALID_CHG);
}
+ /*
+ * Controllers like mXT1386 have a dedicated WAKE line that could be
+ * connected to a GPIO or to I2C SCL pin, or permanently asserted low.
+ *
+ * This WAKE line is used for waking controller from a deep-sleep and
+ * it needs to be asserted low for 25 milliseconds before I2C transfers
+ * could be accepted by controller if it was in a deep-sleep mode.
+ * Controller will go into sleep automatically after 2 seconds of
+ * inactivity if WAKE line is deasserted and deep sleep is activated.
+ *
+ * If WAKE line is connected to I2C SCL pin, then the first I2C transfer
+ * will get an instant NAK and transfer needs to be retried after 25ms.
+ *
+ * If WAKE line is connected to a GPIO line, the line must be asserted
+ * 25ms before the host attempts to communicate with the controller.
+ */
+ device_property_read_u32(&client->dev, "atmel,wakeup-method",
+ &data->wakeup_method);
+
error = mxt_initialize(data);
if (error)
goto err_disable_regulators;