Re: [PATCH v2 2/2] Input: drv260x: Fix suspend and resume sequencing

Raise it before communicating on resume, observe the startup delay,
and rerun device initialization. Restore the same state if regulator
shutdown aborts suspend.

Assisted-by: Codex:gpt-5.6-sol sparse
Signed-off-by: Maurizio Casciano <redacted>
---
 drivers/input/misc/drv260x.c | 42 ++++++++++++++++++++++++++++--------
 1 file changed, 33 insertions(+), 9 deletions(-)

diff --git a/drivers/input/misc/drv260x.c b/drivers/input/misc/drv260x.c
index f26a9052edd2..c64a86bc9bfd 100644
--- a/drivers/input/misc/drv260x.c
+++ b/drivers/input/misc/drv260x.c

@@ -181,6 +181,7 @@
  * @work: Work item used to off load the enable/disable of the vibration
  * @enable_gpio: Pointer to the gpio used for enable/disabling
  * @regulator: Pointer to the regulator for the IC
+ * @suspended: Whether force-feedback work must remain quiesced
  * @magnitude: Magnitude of the vibration event
  * @mode: The operating mode of the IC (LRA_NO_CAL, ERM or LRA)
  * @library: The vibration library to be used

@@ -194,6 +195,7 @@ struct drv260x_data {
 	struct work_struct work;
 	struct gpio_desc *enable_gpio;
 	struct regulator *regulator;
+	bool suspended;
 	u8 magnitude;
 	u32 mode;
 	u32 library;

@@ -215,6 +217,13 @@ static int drv260x_calculate_voltage(unsigned int voltage)
 	return (voltage * 255 / 5600);
 }
 
+static void drv260x_set_suspended(struct drv260x_data *haptics,
+				  bool suspended)
+{
+	scoped_guard(spinlock_irqsave, &haptics->input_dev->event_lock)
+		haptics->suspended = suspended;
+}
+
 static void drv260x_worker(struct work_struct *work)
 {
 	struct drv260x_data *haptics = container_of(work, struct drv260x_data, work);

@@ -243,6 +252,9 @@ static int drv260x_haptics_play(struct input_dev *input, void *data,
 {
 	struct drv260x_data *haptics = input_get_drvdata(input);
 
+	if (haptics->suspended)
+		return 0;
+
 	/* Scale u16 magnitude into u8 register value */
 	if (effect->u.rumble.strong_magnitude > 0)
 		haptics->magnitude = effect->u.rumble.strong_magnitude >> 8;

@@ -583,17 +595,21 @@ static int drv260x_probe(struct i2c_client *client)
 static int drv260x_suspend(struct device *dev)
 {
 	struct drv260x_data *haptics = dev_get_drvdata(dev);
-	int error;
+	int error, restore_error;
 
 	guard(mutex)(&haptics->input_dev->mutex);
 
 	if (input_device_enabled(haptics->input_dev)) {
+		drv260x_set_suspended(haptics, true);
+		cancel_work_sync(&haptics->work);
+
 		error = regmap_update_bits(haptics->regmap,
 					   DRV260X_MODE,
 					   DRV260X_STANDBY_MASK,
 					   DRV260X_STANDBY);
 		if (error) {
 			dev_err(dev, "Failed to set standby mode\n");
+			drv260x_set_suspended(haptics, false);
 			return error;
 		}
 

@@ -602,9 +618,15 @@ static int drv260x_suspend(struct device *dev)
 		error = regulator_disable(haptics->regulator);
 		if (error) {
 			dev_err(dev, "Failed to disable regulator\n");
-			regmap_update_bits(haptics->regmap,
-					   DRV260X_MODE,
-					   DRV260X_STANDBY_MASK, 0);
+
+			gpiod_set_value(haptics->enable_gpio, 1);
+			usleep_range(250, 500);
+			restore_error = drv260x_init(haptics);
+			if (restore_error)
+				dev_err(dev, "Failed to restore configuration: %d\n",
+					restore_error);
+
+			drv260x_set_suspended(haptics, false);