@@ -38,6 +38,9 @@
#define WORK_REGISTER_NUM_X 0x33
#define WORK_REGISTER_NUM_Y 0x34
+#define PMOD_REGISTER_ACTIVE 0x00
+#define PMOD_REGISTER_HIBERNATE 0x03
+
#define M09_REGISTER_THRESHOLD 0x80
#define M09_REGISTER_GAIN 0x92
#define M09_REGISTER_OFFSET 0x93
@@ -53,6 +56,7 @@
#define WORK_REGISTER_OPMODE 0x3c
#define FACTORY_REGISTER_OPMODE 0x01
+#define PMOD_REGISTER_OPMODE 0xa5
#define TOUCH_EVENT_DOWN 0x00
#define TOUCH_EVENT_UP 0x01
@@ -65,6 +69,12 @@
#define EDT_RAW_DATA_RETRIES 100
#define EDT_RAW_DATA_DELAY 1000 /* usec */
+enum edt_pmode {
+ EDT_PMODE_NOT_SUPPORTED,
+ EDT_PMODE_HIBERNATE,
+ EDT_PMODE_POWEROFF,
+};
+
enum edt_ver {
EDT_M06,
EDT_M09,
@@ -103,6 +113,7 @@ struct edt_ft5x06_ts_data {
struct mutex mutex;
bool factory_mode;
+ enum edt_pmode suspend_mode;
int threshold;
int gain;
int offset;
@@ -1125,6 +1136,19 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
return error;
}
+ /*
+ * Check which sleep modes we can support. Power-off requieres the
+ * reset-pin to ensure correct power-down/power-up behaviour. Start with
+ * the EDT_PMODE_POWEROFF test since this is the deepest possible sleep
+ * mode.
+ */
+ if (tsdata->reset_gpio)
+ tsdata->suspend_mode = EDT_PMODE_POWEROFF;
+ else if (tsdata->wake_gpio)
+ tsdata->suspend_mode = EDT_PMODE_HIBERNATE;
+ else
+ tsdata->suspend_mode = EDT_PMODE_NOT_SUPPORTED;
+
if (tsdata->wake_gpio) {
usleep_range(5000, 6000);
gpiod_set_value_cansleep(tsdata->wake_gpio, 1);
@@ -1238,6 +1262,104 @@ static int edt_ft5x06_ts_remove(struct i2c_client *client)
return 0;
}
+static int __maybe_unused edt_ft5x06_ts_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
+ struct gpio_desc *reset_gpio = tsdata->reset_gpio;
+ int ret;
+
+ if (device_may_wakeup(dev))
+ return 0;
+
+ if (tsdata->suspend_mode == EDT_PMODE_NOT_SUPPORTED)
+ return 0;
+
+ /* Enter hibernate mode. */
+ ret = edt_ft5x06_register_write(tsdata, PMOD_REGISTER_OPMODE,
+ PMOD_REGISTER_HIBERNATE);
+ if (ret)
+ dev_warn(dev, "Failed to set hibernate mode\n");
+
+ if (tsdata->suspend_mode == EDT_PMODE_HIBERNATE)
+ return 0;
+
+ /*
+ * Power-off according the datasheet. Cut the power may leaf the irq
+ * line in an undefined state depending on the host pull resistor
+ * settings. Disable the irq to avoid adjusting each host till the
+ * device is back in a full functional state.
+ */
+ disable_irq(tsdata->client->irq);
+
+ gpiod_set_value_cansleep(reset_gpio, 1);
+ usleep_range(1000, 2000);
+
+ ret = regulator_disable(tsdata->vcc);
+ if (ret)
+ dev_warn(dev, "Failed to disable vcc\n");
+
+ return 0;
+}
+
+static int __maybe_unused edt_ft5x06_ts_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
+ int ret = 0;
+
+ if (device_may_wakeup(dev))
+ return 0;
+
+ if (tsdata->suspend_mode == EDT_PMODE_NOT_SUPPORTED)
+ return 0;
+
+ if (tsdata->suspend_mode == EDT_PMODE_POWEROFF) {
+ struct gpio_desc *reset_gpio = tsdata->reset_gpio;
+
+ /*
+ * We can't check if the regulator is a dummy or a real
+ * regulator. So we need to specify the 5ms reset time (T_rst)
+ * here instead of the 100us T_rtp time. We also need to wait
+ * 300ms in case it was a real supply and the power was cutted
+ * of. Toggle the reset pin is also a way to exit the hibernate
+ * mode.
+ */
+ gpiod_set_value_cansleep(reset_gpio, 1);
+ usleep_range(5000, 6000);
+
+ ret = regulator_enable(tsdata->vcc);
+ if (ret) {
+ dev_err(dev, "Failed to enable vcc\n");
+ return ret;
+ }
+
+ usleep_range(1000, 2000);
+ gpiod_set_value_cansleep(reset_gpio, 0);
+ msleep(300);
+
+ edt_ft5x06_restore_reg_parameters(tsdata);
+ enable_irq(tsdata->client->irq);
+
+#ifdef CONFIG_DEBUG_FS
+ if (tsdata->factory_mode)
+ ret = edt_ft5x06_factory_mode(tsdata);
+#endif
+ } else {
+ struct gpio_desc *wake_gpio = tsdata->wake_gpio;
+
+ gpiod_set_value_cansleep(wake_gpio, 0);
+ usleep_range(5000, 6000);
+ gpiod_set_value_cansleep(wake_gpio, 1);
+ }
+
+
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(edt_ft5x06_ts_pm_ops,
+ edt_ft5x06_ts_suspend, edt_ft5x06_ts_resume);
+
static const struct edt_i2c_chip_data edt_ft5x06_data = {
.max_support_points = 5,
};
@@ -1276,6 +1398,7 @@ static struct i2c_driver edt_ft5x06_ts_driver = {
.driver = {
.name = "edt_ft5x06",
.of_match_table = edt_ft5x06_of_match,
+ .pm = &edt_ft5x06_ts_pm_ops,
},
.id_table = edt_ft5x06_ts_id,
.probe = edt_ft5x06_ts_probe,
It is possible to bring the device into a deep sleep state. To exit this state the reset or wakeup pin must be toggeled as documented in [1]. Because of the poor documentation I used the several downstream kernels [2] and other applications notes [3] to indentify the related registers. Furthermore I added the support to disable the device completely which is obviously the most effective power-saving mechanism. This mechanism needs the reset pin to ensure the power-up/down sequence. We can't apply any of these power-saving mechanism if both pins are missing (not connected) or if it is a wakeup device. [1] https://www.newhavendisplay.com/appnotes/datasheets/touchpanel/FT5x26.pdf https://www.newhavendisplay.com/appnotes/datasheets/touchpanel/FT5x06.pdf [2] https://github.com/linux-sunxi/linux-sunxi/blob/sunxi-3.4/drivers/input/touchscreen/ft5x_ts.c https://github.com/Pablito2020/focaltech-touch-driver/blob/master/ft5336_driver.c [3] https://www.newhavendisplay.com/appnotes/datasheets/touchpanel/FT5x16_registers.pdf Signed-off-by: Marco Felsch <m.felsch@pengutronix.de> --- v4: - improve suspend modi handling - restore configuration if poweroff suspend mode was selected - check return values during resume - add comments about the delays - adapt commit message v3: - drop enable/disable_irq_wake() v2: - adapt commit message - don't return errors during suspend/resume - replace dev_err() by dev_warn() - add support to disable the regulator too drivers/input/touchscreen/edt-ft5x06.c | 123 +++++++++++++++++++++++++ 1 file changed, 123 insertions(+)