Input: cyapa - fix for losing events during device power transitions

When changing the scan rate as part of runtime-resume process we may lose
some of the events, because:

1) for gen3 trackpads, the driver must msleep() some time to ensure that
the device is ready to accept next command;

2) for gen5 and later trackpads, the queue dumping function will simply
ignore the events when waiting for the set power mode command response.

The solution is to keep polling and report those valid events when the set
power mode command is in progress.

Signed-off-by: Dudley Du <dudl@cypress.com>
Tested-by: Jeremiah Mahler <jmmahler@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 79 insertions, 29 deletions

diff --git a/drivers/input/mouse/cyapa_gen3.c b/drivers/input/mouse/cyapa_gen3.c
index 1a9d12ae7538..f9600753eca5 100644
--- a/drivers/input/mouse/cyapa_gen3.c
+++ b/drivers/input/mouse/cyapa_gen3.c
@@ -269,6 +269,7 @@ static const struct cyapa_cmd_len cyapa_smbus_cmds[] = {
 	{ CYAPA_SMBUS_MIN_BASELINE, 1 },	/* CYAPA_CMD_MIN_BASELINE */
 };
 
+static int cyapa_gen3_try_poll_handler(struct cyapa *cyapa);
 
 /*
  * cyapa_smbus_read_block - perform smbus block read command
@@ -950,12 +951,14 @@ static u16 cyapa_get_wait_time_for_pwr_cmd(u8 pwr_mode)
  * Device power mode can only be set when device is in operational mode.
  */
 static int cyapa_gen3_set_power_mode(struct cyapa *cyapa, u8 power_mode,
-		u16 always_unused, bool is_suspend_unused)
+		u16 always_unused, enum cyapa_pm_stage pm_stage)
 {
-	int ret;
+	struct input_dev *input = cyapa->input;
 	u8 power;
 	int tries;
-	u16 sleep_time;
+	int sleep_time;
+	int interval;
+	int ret;
 
 	if (cyapa->state != CYAPA_STATE_OP)
 		return 0;
@@ -977,7 +980,7 @@ static int cyapa_gen3_set_power_mode(struct cyapa *cyapa, u8 power_mode,
 	if ((ret & PWR_MODE_MASK) == power_mode)
 		return 0;
 
-	sleep_time = cyapa_get_wait_time_for_pwr_cmd(ret & PWR_MODE_MASK);
+	sleep_time = (int)cyapa_get_wait_time_for_pwr_cmd(ret & PWR_MODE_MASK);
 	power = ret;
 	power &= ~PWR_MODE_MASK;
 	power |= power_mode & PWR_MODE_MASK;
@@ -995,7 +998,23 @@ static int cyapa_gen3_set_power_mode(struct cyapa *cyapa, u8 power_mode,
 	 * doing so before issuing the next command may result in errors
 	 * depending on the command's content.
 	 */
-	msleep(sleep_time);
+	if (cyapa->operational && input && input->users &&
+	    (pm_stage == CYAPA_PM_RUNTIME_SUSPEND ||
+	     pm_stage == CYAPA_PM_RUNTIME_RESUME)) {
+		/* Try to polling in 120Hz, read may fail, just ignore it. */
+		interval = 1000 / 120;
+		while (sleep_time > 0) {
+			if (sleep_time > interval)
+				msleep(interval);
+			else
+				msleep(sleep_time);
+			sleep_time -= interval;
+			cyapa_gen3_try_poll_handler(cyapa);
+		}
+	} else {
+		msleep(sleep_time);
+	}
+
 	return ret;
 }
 
@@ -1112,7 +1131,7 @@ static int cyapa_gen3_do_operational_check(struct cyapa *cyapa)
 		 * may cause problems, so we set the power mode first here.
 		 */
 		error = cyapa_gen3_set_power_mode(cyapa,
-				PWR_MODE_FULL_ACTIVE, 0, false);
+				PWR_MODE_FULL_ACTIVE, 0, CYAPA_PM_ACTIVE);
 		if (error)
 			dev_err(dev, "%s: set full power mode failed: %d\n",
 				__func__, error);
@@ -1168,32 +1187,16 @@ static bool cyapa_gen3_irq_cmd_handler(struct cyapa *cyapa)
 	return false;
 }
 
-static int cyapa_gen3_irq_handler(struct cyapa *cyapa)
+static int cyapa_gen3_event_process(struct cyapa *cyapa,
+				    struct cyapa_reg_data *data)
 {
 	struct input_dev *input = cyapa->input;
-	struct device *dev = &cyapa->client->dev;
-	struct cyapa_reg_data data;
 	int num_fingers;
-	int ret;
 	int i;
 
-	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
-	if (ret != sizeof(data)) {
-		dev_err(dev, "failed to read report data, (%d)\n", ret);
-		return -EINVAL;
-	}
-
-	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
-	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
-	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
-		dev_err(dev, "invalid device state bytes, %02x %02x\n",
-			data.device_status, data.finger_btn);
-		return -EINVAL;
-	}
-
-	num_fingers = (data.finger_btn >> 4) & 0x0f;
+	num_fingers = (data->finger_btn >> 4) & 0x0f;
 	for (i = 0; i < num_fingers; i++) {
-		const struct cyapa_touch *touch = &data.touches[i];
+		const struct cyapa_touch *touch = &data->touches[i];
 		/* Note: touch->id range is 1 to 15; slots are 0 to 14. */
 		int slot = touch->id - 1;
 
@@ -1210,18 +1213,65 @@ static int cyapa_gen3_irq_handler(struct cyapa *cyapa)
 
 	if (cyapa->btn_capability & CAPABILITY_LEFT_BTN_MASK)
 		input_report_key(input, BTN_LEFT,
-				 !!(data.finger_btn & OP_DATA_LEFT_BTN));
+				 !!(data->finger_btn & OP_DATA_LEFT_BTN));
 	if (cyapa->btn_capability & CAPABILITY_MIDDLE_BTN_MASK)
 		input_report_key(input, BTN_MIDDLE,
-				 !!(data.finger_btn & OP_DATA_MIDDLE_BTN));
+				 !!(data->finger_btn & OP_DATA_MIDDLE_BTN));
 	if (cyapa->btn_capability & CAPABILITY_RIGHT_BTN_MASK)
 		input_report_key(input, BTN_RIGHT,
-				 !!(data.finger_btn & OP_DATA_RIGHT_BTN));
+				 !!(data->finger_btn & OP_DATA_RIGHT_BTN));
 	input_sync(input);
 
 	return 0;
 }
 
+static int cyapa_gen3_irq_handler(struct cyapa *cyapa)
+{
+	struct device *dev = &cyapa->client->dev;
+	struct cyapa_reg_data data;
+	int ret;
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
+	if (ret != sizeof(data)) {
+		dev_err(dev, "failed to read report data, (%d)\n", ret);
+		return -EINVAL;
+	}
+
+	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
+	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
+	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID) {
+		dev_err(dev, "invalid device state bytes: %02x %02x\n",
+			data.device_status, data.finger_btn);
+		return -EINVAL;
+	}
+
+	return cyapa_gen3_event_process(cyapa, &data);
+}
+
+/*
+ * This function will be called in the cyapa_gen3_set_power_mode function,
+ * and it's known that it may failed in some situation after the set power
+ * mode command was sent. So this function is aimed to avoid the knwon
+ * and unwanted output I2C and data parse error messages.
+ */
+static int cyapa_gen3_try_poll_handler(struct cyapa *cyapa)
+{
+	struct cyapa_reg_data data;
+	int ret;
+
+	ret = cyapa_read_block(cyapa, CYAPA_CMD_GROUP_DATA, (u8 *)&data);
+	if (ret != sizeof(data))
+		return -EINVAL;
+
+	if ((data.device_status & OP_STATUS_SRC) != OP_STATUS_SRC ||
+	    (data.device_status & OP_STATUS_DEV) != CYAPA_DEV_NORMAL ||
+	    (data.finger_btn & OP_DATA_VALID) != OP_DATA_VALID)
+		return -EINVAL;
+
+	return cyapa_gen3_event_process(cyapa, &data);
+
+}
+
 static int cyapa_gen3_initialize(struct cyapa *cyapa) { return 0; }
 static int cyapa_gen3_bl_initiate(struct cyapa *cyapa,
 		const struct firmware *fw) { return 0; }