[PATCH v2 13/49] Input: atmel_mxt_ts - release touch state during suspend

From: Jiada Wang
Date: Tue Aug 27 2019 - 02:28:00 EST


From: Nick Dyer <nick.dyer@xxxxxxxxxxx>

If fingers are down as the MXT chip goes into suspend it does not send a
lift message. In addition, it may not complete its final measurement cycle
immediately, which means touch messages may be received by the interrupt
handler after mxt_stop() has completed.

So:
- disable irq during suspend
- flush any messages created after suspend
- tell app layer that slots were released at suspend

Signed-off-by: Nick Dyer <nick.dyer@xxxxxxxxxxx>
Acked-by: Benson Leung <bleung@xxxxxxxxxxxx>
Acked-by: Yufeng Shen <miletus@xxxxxxxxxxxx>
(cherry picked from ndyer/linux/for-upstream commit 26794433086dbc7dea18d2f6a1c8d61ab25bcfda)
[gdavis: Resolve forward port conflicts due to applying upstream
commit 96a938aa214e ("Input: atmel_mxt_ts - remove platform
data support").]
Signed-off-by: George G. Davis <george_davis@xxxxxxxxxx>
[gdavis: Squash fix from Dirk Behme:
- Input: atmel_mxt_ts - remove superfluous data->suspended]
Signed-off-by: Dirk Behme <dirk.behme@xxxxxxxxxxxx>
---
Notes:
- Squash fix from Dirk Behme:
+ Input: atmel_mxt_ts - remove superfluous data->suspended

data->suspended is already set to false in mxt_load_fw(), so it's not
needed here.

Signed-off-by: Jiada Wang <jiada_wang@xxxxxxxxxx>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 52 ++++++++++++++++++++++--
1 file changed, 49 insertions(+), 3 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 26861252c088..4d28b30c4f76 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -372,6 +372,9 @@ struct mxt_data {
unsigned int t19_num_keys;

enum mxt_suspend_mode suspend_mode;
+
+ /* Indicates whether device is in suspend */
+ bool suspended;
};

struct mxt_vb2_buffer {
@@ -1151,10 +1154,10 @@ static int mxt_proc_message(struct mxt_data *data, u8 *message)
mxt_proc_t42_messages(data, message);
} else if (report_id == data->T48_reportid) {
mxt_proc_t48_messages(data, message);
- } else if (!data->input_dev) {
+ } else if (!data->input_dev || data->suspended) {
/*
- * Do not report events if input device
- * is not yet registered.
+ * Do not report events if input device is not
+ * yet registered or returning from suspend
*/
mxt_dump_message(data, message);
} else if (report_id >= data->T9_reportid_min &&
@@ -3135,6 +3138,11 @@ static int mxt_load_fw(struct device *dev, const char *fn)
if (ret)
goto release_firmware;

+ if (data->suspended) {
+ enable_irq(data->irq);
+ data->suspended = false;
+ }
+
if (!data->in_bootloader) {
/* Change to the bootloader mode */
data->in_bootloader = true;
@@ -3306,8 +3314,27 @@ static void mxt_sysfs_remove(struct mxt_data *data)
sysfs_remove_group(&client->dev.kobj, &mxt_attr_group);
}

+static void mxt_reset_slots(struct mxt_data *data)
+{
+ struct input_dev *input_dev = data->input_dev;
+ int id;
+
+ if (!input_dev)
+ return;
+
+ for (id = 0; id < data->num_touchids; id++) {
+ input_mt_slot(input_dev, id);
+ input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, 0);
+ }
+
+ mxt_input_sync(data);
+}
+
static void mxt_start(struct mxt_data *data)
{
+ if (!data->suspended || data->in_bootloader)
+ return;
+
switch (data->suspend_mode) {
case MXT_SUSPEND_T9_CTRL:
mxt_soft_reset(data);
@@ -3320,16 +3347,29 @@ static void mxt_start(struct mxt_data *data)

case MXT_SUSPEND_DEEP_SLEEP:
default:
+ /*
+ * Discard any touch messages still in message buffer
+ * from before chip went to sleep
+ */
+ mxt_process_messages_until_invalid(data);
+
mxt_set_t7_power_cfg(data, MXT_POWER_CFG_RUN);

/* Recalibrate since chip has been in deep sleep */
mxt_t6_command(data, MXT_COMMAND_CALIBRATE, 1, false);
+
+ mxt_acquire_irq(data);
break;
}
+
+ data->suspended = false;
}

static void mxt_stop(struct mxt_data *data)
{
+ if (data->suspended || data->in_bootloader)
+ return;
+
switch (data->suspend_mode) {
case MXT_SUSPEND_T9_CTRL:
/* Touch disable */
@@ -3339,9 +3379,15 @@ static void mxt_stop(struct mxt_data *data)

case MXT_SUSPEND_DEEP_SLEEP:
default:
+ disable_irq(data->irq);
+
mxt_set_t7_power_cfg(data, MXT_POWER_CFG_DEEPSLEEP);
+
+ mxt_reset_slots(data);
break;
}
+
+ data->suspended = true;
}

static int mxt_input_open(struct input_dev *dev)
--
2.19.2