[PATCH v3 3/3] platform/x86: thinkpad_acpi: Add support for lap sensor

[Mark Pearson <markpearson@lenovo.com>]

Use input device event support for notifying userspace of lap mode sensor
state changes.

Reviewed-by: Nitin Joshi <njoshi1@lenovo.com>
Signed-off-by: Mark Pearson <markpearson@lenovo.com>
---
Changes in V2:
 - Update commit message to be correct

Changes in V3:
 - Update lap sensor code with same fixes applied to palm sensor code.
 - Correct error handling in init so returns an error if one
   encountered.

 drivers/platform/x86/thinkpad_acpi.c | 61 ++++++++++++++++++++++++----
 1 file changed, 52 insertions(+), 9 deletions(-)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 3cb07c12a705..fe438a5e1dbe 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -9928,6 +9928,22 @@ static struct ibm_struct dytc_driver_data = {
 
 struct input_dev *tpacpi_sw_dev;
 bool has_palmsensor;
+bool has_lapsensor;
+
+static int lapsensor_get(bool *present, bool *state)
+{
+	acpi_handle dytc_handle;
+	int output;
+
+	*present = false;
+	if (ACPI_FAILURE(acpi_get_handle(hkey_handle, "DYTC", &dytc_handle)))
+		return -ENODEV;
+	if (!acpi_evalf(dytc_handle, &output, NULL, "dd", DYTC_CMD_GET))
+		return -EIO;
+	*present = true; /*If we get his far, we have lapmode support*/
+	*state = output & BIT(DYTC_GET_LAPMODE_BIT) ? true : false;
+	return 0;
+}
 
 static int palmsensor_get(bool *present, bool *state)
 {
@@ -9958,21 +9974,40 @@ static void palmsensor_refresh(void)
 	}
 }
 
+static void lapsensor_refresh(void)
+{
+	bool state;
+	int err;
+
+	if (has_lapsensor) {
+		err = lapsensor_get(&has_lapsensor, &state);
+		if (err)
+			return;
+		input_report_switch(tpacpi_sw_dev, SW_LAP_PROXIMITY, state);
+		input_sync(tpacpi_sw_dev);
+	}
+}
+
 static int tpacpi_proxsensor_init(struct ibm_init_struct *iibm)
 {
-	int palm_err, err;
-	bool palm_state;
+	int palm_err, lap_err, err;
+	bool palm_state, lap_state;
 
 	palm_err = palmsensor_get(&has_palmsensor, &palm_state);
-	/* If support isn't available (ENODEV) then quit, but don't return an error */
-	if (palm_err == -ENODEV)
+	lap_err = lapsensor_get(&has_lapsensor, &lap_state);
+	/*
+	 * If support isn't available (ENODEV) for both devices then quit, but
+	 * don't return an error.
+	 */
+	if ((palm_err == -ENODEV) && (lap_err == -ENODEV))
 		return 1;
-
 	/* Otherwise, if there was an error return it */
 	if (palm_err && (palm_err != ENODEV))
 		return palm_err;
+	if (lap_err && (lap_err != ENODEV))
+		return lap_err;
 
-	if (has_palmsensor) {
+	if (has_palmsensor || has_lapsensor) {
 		tpacpi_sw_dev = input_allocate_device();
 		if (!tpacpi_sw_dev)
 			return -ENOMEM;
@@ -9984,8 +10019,14 @@ static int tpacpi_proxsensor_init(struct ibm_init_struct *iibm)
 		tpacpi_sw_dev->id.version = TPACPI_HKEY_INPUT_VERSION;
 		tpacpi_sw_dev->dev.parent = &tpacpi_pdev->dev;
 
-		input_set_capability(tpacpi_sw_dev, EV_SW, SW_PALMREST_PROXIMITY);
-		input_report_switch(tpacpi_sw_dev, SW_PALMREST_PROXIMITY, palm_state);
+		if (has_palmsensor) {
+			input_set_capability(tpacpi_sw_dev, EV_SW, SW_PALMREST_PROXIMITY);
+			input_report_switch(tpacpi_sw_dev, SW_PALMREST_PROXIMITY, palm_state);
+		}
+		if (has_lapsensor) {
+			input_set_capability(tpacpi_sw_dev, EV_SW, SW_LAP_PROXIMITY);
+			input_report_switch(tpacpi_sw_dev, SW_LAP_PROXIMITY, lap_state);
+		}
 		err = input_register_device(tpacpi_sw_dev);
 		if (err) {
 			input_free_device(tpacpi_sw_dev);
@@ -10053,8 +10094,10 @@ static void tpacpi_driver_event(const unsigned int hkey_event)
 		mutex_unlock(&kbdlight_mutex);
 	}
 
-	if (hkey_event == TP_HKEY_EV_THM_CSM_COMPLETED)
+	if (hkey_event == TP_HKEY_EV_THM_CSM_COMPLETED) {
 		dytc_lapmode_refresh();
+		lapsensor_refresh();
+	}
 
 }
 
-- 
2.28.0