[PATCH v2 35/49] input: atmel_mxt_ts: Add Missing Delay for reset handling of Atmel touch panel controller in detachable displays.

[PATCH v2 35/49] input: atmel_mxt_ts: Add Missing Delay for reset handling of Atmel touch panel controller in detachable displays.

[Jiada Wang]

From: keerthikumarp <Keerthikumar.Padmanabha@in.bosch.com>

In case of attached display, the touchpanel reset is controlled
via imx gpio's from  atmel driver and the delay between
touchpanel reset and the time at which the chip becomes capable to
communicate with the host processor, has be taken care.

However in case of detachable displays, the touchpanel reset is
controlled via a deserializer gpio which is triggered just before
the atmel driver is probed.The delay between touchpanel reset and
the time at which the chip becomes capable to communicate (as
specified in datasheet) was not being accounted for. This patch
introduces that delay.

Signed-off-by: keerthikumarp <Keerthikumar.Padmanabha@in.bosch.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 35f41bfa70d5..192cf47ff5f4 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -4110,6 +4110,10 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
 		msleep(MXT_RESET_GPIO_TIME);
 		gpiod_set_value(data->reset_gpio, 1);
 		msleep(MXT_RESET_INVALID_CHG);
+	} else {
+		dev_dbg(&client->dev,
+			"atmel reset pin not found in device tree");
+		msleep(MXT_RESET_TIME);
 	}
 
 	error = mxt_initialize(data);
-- 
2.19.2

[PATCH v2 35/49] input: atmel_mxt_ts: Add Missing Delay for reset handling of Atmel touch panel controller in detachable displays.

[Jiada Wang]

From: keerthikumarp <Keerthikumar.Padmanabha@in.bosch.com>

In case of attached display, the touchpanel reset is controlled
via imx gpio's from  atmel driver and the delay between
touchpanel reset and the time at which the chip becomes capable to
communicate with the host processor, has be taken care.

However in case of detachable displays, the touchpanel reset is
controlled via a deserializer gpio which is triggered just before
the atmel driver is probed.The delay between touchpanel reset and
the time at which the chip becomes capable to communicate (as
specified in datasheet) was not being accounted for. This patch
introduces that delay.

Signed-off-by: keerthikumarp <Keerthikumar.Padmanabha@in.bosch.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 35f41bfa70d5..192cf47ff5f4 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -4110,6 +4110,10 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
 		msleep(MXT_RESET_GPIO_TIME);
 		gpiod_set_value(data->reset_gpio, 1);
 		msleep(MXT_RESET_INVALID_CHG);
+	} else {
+		dev_dbg(&client->dev,
+			"atmel reset pin not found in device tree");
+		msleep(MXT_RESET_TIME);
 	}
 
 	error = mxt_initialize(data);
-- 
2.19.2

[PATCH v2 36/49] Input: atmel_mxt_ts: Add support for run self-test routine.

[Jiada Wang]

From: Nikhil Ravindran <Nikhil.Ravindran@in.bosch.com>

The self test object T25 runs self test routines in device to find faults
Sysfs entry add to start self test routine and read back the test results
for atmel touchcontrollers.The feature will be used for A-IVI and CAF projects.

Signed-off-by: Nikhil Ravindran <Nikhil.Ravindran@in.bosch.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 111 +++++++++++++++++++++++
 1 file changed, 111 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 192cf47ff5f4..aa33962ed1dc 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -336,6 +336,9 @@ struct mxt_data {
 	u8 t100_aux_ampl;
 	u8 t100_aux_area;
 	u8 t100_aux_vect;
+	u16 T25_address;
+	u8  T25_reportid;
+	u8  t25_msg[6];
 	bool debug_enabled;
 	bool debug_v2_enabled;
 	u8 *debug_msg_data;
@@ -413,6 +416,8 @@ struct mxt_data {
 
 	/* Indicates whether device is updating configuration */
 	bool updating_config;
+
+	bool t25_status;
 };
 
 struct mxt_vb2_buffer {
@@ -1356,6 +1361,24 @@ static void mxt_proc_t93_messages(struct mxt_data *data, u8 *msg)
 	dev_info(dev, "T93 report double tap %d\n", status);
 }
 
+static void mxt_proc_t25_messages(struct mxt_data *data, u8 *msg)
+{
+	struct device *dev = &data->client->dev;
+
+	/* Output debug if status has changed */
+	dev_dbg(dev, "T25 Status 0x%x Info: %x %x %x %x %x\n",
+		msg[1],
+		msg[2],
+		msg[3],
+		msg[4],
+		msg[5],
+		msg[6]);
+
+	/* Save current status */
+	memcpy(&data->t25_msg[0], &msg[1], sizeof(data->t25_msg));
+	data->t25_status = false;
+}
+
 static int mxt_proc_message(struct mxt_data *data, u8 *message)
 {
 	u8 report_id = message[0];
@@ -1386,6 +1409,8 @@ static int mxt_proc_message(struct mxt_data *data, u8 *message)
 	} else if (report_id == data->T19_reportid) {
 		mxt_input_button(data, message);
 		data->update_input = true;
+	} else if (report_id == data->T25_reportid) {
+		mxt_proc_t25_messages(data, message);
 	} else if (report_id >= data->T15_reportid_min
 		   && report_id <= data->T15_reportid_max) {
 		mxt_proc_t15_messages(data, message);
@@ -1610,6 +1635,84 @@ static int mxt_t6_command(struct mxt_data *data, u16 cmd_offset,
 	return 0;
 }
 
+static int mxt_t25_command(struct mxt_data *data, u8 cmd, bool wait)
+{
+	u16 reg;
+	int timeout_counter = 0;
+	int ret;
+	u8  val[2];
+
+	reg = data->T25_address;
+	val[0] = 0x3;
+	val[1] = cmd;
+
+	data->t25_status = true;
+	ret = __mxt_write_reg(data->client, reg, sizeof(val), val);
+	if (ret) {
+		data->t25_status = false;
+		return ret;
+	}
+
+	if (!wait)
+		return 0;
+
+	do {
+		msleep(MXT_WAKEUP_TIME);
+		ret = __mxt_read_reg(data->client, reg + 1, 1, &val[1]);
+		if (ret)
+			return ret;
+	} while ((val[1] != 0) && (timeout_counter++ <= 100));
+
+	if (timeout_counter > 100) {
+		dev_err(&data->client->dev, "Command failed!\n");
+		data->t25_status = false;
+		return -EIO;
+	}
+	return 0;
+}
+
+/* Firmware Version is returned as Major.Minor.Build */
+static ssize_t mxt_t25_selftest_show(struct device *dev, struct
+				     device_attribute *attr, char *buf)
+{
+	struct mxt_data *data = dev_get_drvdata(dev);
+	ssize_t offset = 0;
+
+	if (data->t25_status)
+		return -EAGAIN;
+
+	if (data->t25_msg[0] == 0xFE)
+		offset += scnprintf(buf, PAGE_SIZE, "PASS\n");
+	else
+		offset += scnprintf(buf, PAGE_SIZE, "FAILED\n");
+
+	offset += scnprintf(buf + offset, PAGE_SIZE, "%x %x %x %x %x %x\n",
+		 data->t25_msg[0],
+		 data->t25_msg[1],
+		 data->t25_msg[2],
+		 data->t25_msg[3],
+		 data->t25_msg[4],
+		 data->t25_msg[5]);
+	return offset;
+}
+
+static ssize_t mxt_t25_selftest_store(struct device *dev, struct
+				      device_attribute *attr, const char *buf,
+				      size_t count)
+{
+	struct mxt_data *data = dev_get_drvdata(dev);
+	u32 cmd;
+
+	if (sscanf(buf, "%x", &cmd) == 1) {
+		if (mxt_t25_command(data, (u8)cmd, 1) == 0)
+			return count;
+
+		dev_dbg(dev, "mxt_t25_cmd_store write cmd %x error\n", cmd);
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static int mxt_acquire_irq(struct mxt_data *data)
 {
 	int error;
@@ -2088,6 +2191,8 @@ static void mxt_free_object_table(struct mxt_data *data)
 	data->T15_reportid_max = 0;
 	data->T18_address = 0;
 	data->T19_reportid = 0;
+	data->T25_address = 0;
+	data->T25_reportid = 0;
 	data->T42_reportid_min = 0;
 	data->T42_reportid_max = 0;
 	data->T44_address = 0;
@@ -2175,6 +2280,10 @@ static int mxt_parse_object_table(struct mxt_data *data,
 		case MXT_SPT_COMMSCONFIG_T18:
 			data->T18_address = object->start_address;
 			break;
+		case MXT_SPT_SELFTEST_T25:
+			data->T25_address = object->start_address;
+			data->T25_reportid = min_id;
+			break;
 		case MXT_PROCI_TOUCHSUPPRESSION_T42:
 			data->T42_reportid_min = min_id;
 			data->T42_reportid_max = max_id;
@@ -3761,6 +3870,7 @@ static DEVICE_ATTR(debug_enable, S_IWUSR | S_IRUSR, mxt_debug_enable_show,
 static DEVICE_ATTR(debug_v2_enable, S_IWUSR | S_IRUSR, NULL,
 		   mxt_debug_v2_enable_store);
 static DEVICE_ATTR(debug_notify, S_IRUGO, mxt_debug_notify_show, NULL);
+static DEVICE_ATTR(t25, 0600, mxt_t25_selftest_show, mxt_t25_selftest_store);
 
 static struct attribute *mxt_attrs[] = {
 	&dev_attr_fw_version.attr,
@@ -3771,6 +3881,7 @@ static struct attribute *mxt_attrs[] = {
 	&dev_attr_debug_enable.attr,
 	&dev_attr_debug_v2_enable.attr,
 	&dev_attr_debug_notify.attr,
+	&dev_attr_t25.attr,
 	NULL
 };
 
-- 
2.19.2

[PATCH v2 36/49] Input: atmel_mxt_ts: Add support for run self-test routine.

[Jiada Wang]

From: Nikhil Ravindran <Nikhil.Ravindran@in.bosch.com>

The self test object T25 runs self test routines in device to find faults
Sysfs entry add to start self test routine and read back the test results
for atmel touchcontrollers.The feature will be used for A-IVI and CAF projects.

Signed-off-by: Nikhil Ravindran <Nikhil.Ravindran@in.bosch.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 111 +++++++++++++++++++++++
 1 file changed, 111 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 192cf47ff5f4..aa33962ed1dc 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -336,6 +336,9 @@ struct mxt_data {
 	u8 t100_aux_ampl;
 	u8 t100_aux_area;
 	u8 t100_aux_vect;
+	u16 T25_address;
+	u8  T25_reportid;
+	u8  t25_msg[6];
 	bool debug_enabled;
 	bool debug_v2_enabled;
 	u8 *debug_msg_data;
@@ -413,6 +416,8 @@ struct mxt_data {
 
 	/* Indicates whether device is updating configuration */
 	bool updating_config;
+
+	bool t25_status;
 };
 
 struct mxt_vb2_buffer {
@@ -1356,6 +1361,24 @@ static void mxt_proc_t93_messages(struct mxt_data *data, u8 *msg)
 	dev_info(dev, "T93 report double tap %d\n", status);
 }
 
+static void mxt_proc_t25_messages(struct mxt_data *data, u8 *msg)
+{
+	struct device *dev = &data->client->dev;
+
+	/* Output debug if status has changed */
+	dev_dbg(dev, "T25 Status 0x%x Info: %x %x %x %x %x\n",
+		msg[1],
+		msg[2],
+		msg[3],
+		msg[4],
+		msg[5],
+		msg[6]);
+
+	/* Save current status */
+	memcpy(&data->t25_msg[0], &msg[1], sizeof(data->t25_msg));
+	data->t25_status = false;
+}
+
 static int mxt_proc_message(struct mxt_data *data, u8 *message)
 {
 	u8 report_id = message[0];
@@ -1386,6 +1409,8 @@ static int mxt_proc_message(struct mxt_data *data, u8 *message)
 	} else if (report_id == data->T19_reportid) {
 		mxt_input_button(data, message);
 		data->update_input = true;
+	} else if (report_id == data->T25_reportid) {
+		mxt_proc_t25_messages(data, message);
 	} else if (report_id >= data->T15_reportid_min
 		   && report_id <= data->T15_reportid_max) {
 		mxt_proc_t15_messages(data, message);
@@ -1610,6 +1635,84 @@ static int mxt_t6_command(struct mxt_data *data, u16 cmd_offset,
 	return 0;
 }
 
+static int mxt_t25_command(struct mxt_data *data, u8 cmd, bool wait)
+{
+	u16 reg;
+	int timeout_counter = 0;
+	int ret;
+	u8  val[2];
+
+	reg = data->T25_address;
+	val[0] = 0x3;
+	val[1] = cmd;
+
+	data->t25_status = true;
+	ret = __mxt_write_reg(data->client, reg, sizeof(val), val);
+	if (ret) {
+		data->t25_status = false;
+		return ret;
+	}
+
+	if (!wait)
+		return 0;
+
+	do {
+		msleep(MXT_WAKEUP_TIME);
+		ret = __mxt_read_reg(data->client, reg + 1, 1, &val[1]);
+		if (ret)
+			return ret;
+	} while ((val[1] != 0) && (timeout_counter++ <= 100));
+
+	if (timeout_counter > 100) {
+		dev_err(&data->client->dev, "Command failed!\n");
+		data->t25_status = false;
+		return -EIO;
+	}
+	return 0;
+}
+
+/* Firmware Version is returned as Major.Minor.Build */
+static ssize_t mxt_t25_selftest_show(struct device *dev, struct
+				     device_attribute *attr, char *buf)
+{
+	struct mxt_data *data = dev_get_drvdata(dev);
+	ssize_t offset = 0;
+
+	if (data->t25_status)
+		return -EAGAIN;
+
+	if (data->t25_msg[0] == 0xFE)
+		offset += scnprintf(buf, PAGE_SIZE, "PASS\n");
+	else
+		offset += scnprintf(buf, PAGE_SIZE, "FAILED\n");
+
+	offset += scnprintf(buf + offset, PAGE_SIZE, "%x %x %x %x %x %x\n",
+		 data->t25_msg[0],
+		 data->t25_msg[1],
+		 data->t25_msg[2],
+		 data->t25_msg[3],
+		 data->t25_msg[4],
+		 data->t25_msg[5]);
+	return offset;
+}
+
+static ssize_t mxt_t25_selftest_store(struct device *dev, struct
+				      device_attribute *attr, const char *buf,
+				      size_t count)
+{
+	struct mxt_data *data = dev_get_drvdata(dev);
+	u32 cmd;
+
+	if (sscanf(buf, "%x", &cmd) == 1) {
+		if (mxt_t25_command(data, (u8)cmd, 1) == 0)
+			return count;
+
+		dev_dbg(dev, "mxt_t25_cmd_store write cmd %x error\n", cmd);
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static int mxt_acquire_irq(struct mxt_data *data)
 {
 	int error;
@@ -2088,6 +2191,8 @@ static void mxt_free_object_table(struct mxt_data *data)
 	data->T15_reportid_max = 0;
 	data->T18_address = 0;
 	data->T19_reportid = 0;
+	data->T25_address = 0;
+	data->T25_reportid = 0;
 	data->T42_reportid_min = 0;
 	data->T42_reportid_max = 0;
 	data->T44_address = 0;
@@ -2175,6 +2280,10 @@ static int mxt_parse_object_table(struct mxt_data *data,
 		case MXT_SPT_COMMSCONFIG_T18:
 			data->T18_address = object->start_address;
 			break;
+		case MXT_SPT_SELFTEST_T25:
+			data->T25_address = object->start_address;
+			data->T25_reportid = min_id;
+			break;
 		case MXT_PROCI_TOUCHSUPPRESSION_T42:
 			data->T42_reportid_min = min_id;
 			data->T42_reportid_max = max_id;
@@ -3761,6 +3870,7 @@ static DEVICE_ATTR(debug_enable, S_IWUSR | S_IRUSR, mxt_debug_enable_show,
 static DEVICE_ATTR(debug_v2_enable, S_IWUSR | S_IRUSR, NULL,
 		   mxt_debug_v2_enable_store);
 static DEVICE_ATTR(debug_notify, S_IRUGO, mxt_debug_notify_show, NULL);
+static DEVICE_ATTR(t25, 0600, mxt_t25_selftest_show, mxt_t25_selftest_store);
 
 static struct attribute *mxt_attrs[] = {
 	&dev_attr_fw_version.attr,
@@ -3771,6 +3881,7 @@ static struct attribute *mxt_attrs[] = {
 	&dev_attr_debug_enable.attr,
 	&dev_attr_debug_v2_enable.attr,
 	&dev_attr_debug_notify.attr,
+	&dev_attr_t25.attr,
 	NULL
 };
 
-- 
2.19.2

[PATCH v2 37/49] Input: atmel_mxt_ts: Limit the max bytes transferred in an i2c transaction

[Jiada Wang]

From: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com>

In mxt_process_messages_until_invalid() function, driver tries to read
all possible reportid in a single i2c transaction. Number of bytes read
is limited by the max_reportid parameter.
If the max_reportid is a very large value, then a large chunk of bytes
will be requested from the controller in a single i2c transaction.
This transaction can fail due to timeout. This is visible when the
Atmel controller is connected to the SOC via a i2c mux hardware.

mxt_process_messages_t44() reads the T44 message which contains the
pending T5 message count. If the number of pending T5 messages returned
by T44 message is too high then there is a risk of i2c transaction
timeout while reading T5 messages in mxt_process_messages_t44().

New property 'atmel,mtu' is created. This property limits the maximum
number of bytes that can read/transferred in an i2c transcation

Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 .../bindings/input/atmel,maxtouch.txt         |  3 +
 drivers/input/touchscreen/atmel_mxt_ts.c      | 65 +++++++++++++++----
 2 files changed, 54 insertions(+), 14 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
index d7db16920083..62c93d94bc5d 100644
--- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
+++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
@@ -42,6 +42,8 @@ Optional properties for main touchpad device:
 
 - atmel,input_name: Override name of input device from the default.
 
+- atmel,mtu: Maximum number of bytes that can read/transferred in an i2c transaction
+
 Example:
 
 	touch@4b {
@@ -49,4 +51,5 @@ Example:
 		reg = <0x4b>;
 		interrupt-parent = <&gpio>;
 		interrupts = <TEGRA_GPIO(W, 3) IRQ_TYPE_LEVEL_LOW>;
+		atmel,mtu = <200>
 	};
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index aa33962ed1dc..169107413823 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -417,6 +417,7 @@ struct mxt_data {
 	/* Indicates whether device is updating configuration */
 	bool updating_config;
 
+	unsigned int mtu;
 	bool t25_status;
 };
 
@@ -1462,11 +1463,32 @@ static int mxt_read_and_process_messages(struct mxt_data *data, u8 count)
 	return num_valid;
 }
 
+static u8 mxt_max_msg_read_count(struct mxt_data *data, u8 max_T5_msg_count)
+{
+	u8 T5_msg_count_limit = data->mtu / data->T5_msg_size;
+
+	if (!data->mtu)
+		return max_T5_msg_count;
+
+	if (data->mtu < data->T5_msg_size) {
+		WARN(1, "mtu set is lesser than the T5 message size\n");
+		/* Return count of 1, as fallback */
+		return 1;
+	}
+	/*
+	 * Return maximum number of T5 messages in single i2c transaction
+	 * based on "atmel,mtu" property.
+	 */
+	return min(T5_msg_count_limit, max_T5_msg_count);
+}
+
 static irqreturn_t mxt_process_messages_t44(struct mxt_data *data)
 {
 	struct device *dev = &data->client->dev;
 	int ret;
-	u8 count, num_left;
+	u8 T5_msg_count, total_pending;
+	u8 total_processed = 0;
+	u8 processed_valid = 0;
 
 	/* Read T44 and T5 together */
 	ret = __mxt_read_reg(data->client, data->T44_address,
@@ -1476,18 +1498,19 @@ static irqreturn_t mxt_process_messages_t44(struct mxt_data *data)
 		return IRQ_NONE;
 	}
 
-	count = data->msg_buf[0];
+	T5_msg_count = data->msg_buf[0];
 
 	/*
 	 * This condition may be caused by the CHG line being configured in
 	 * Mode 0. It results in unnecessary I2C operations but it is benign.
 	 */
-	if (count == 0)
+	if (!T5_msg_count)
 		return IRQ_NONE;
 
-	if (count > data->max_reportid) {
-		dev_warn(dev, "T44 count %d exceeded max report id\n", count);
-		count = data->max_reportid;
+	if (T5_msg_count > data->max_reportid) {
+		dev_warn(dev, "T44 count %d exceeded max report id\n",
+			 T5_msg_count);
+		T5_msg_count = data->max_reportid;
 	}
 
 	/* Process first message */
@@ -1497,16 +1520,25 @@ static irqreturn_t mxt_process_messages_t44(struct mxt_data *data)
 		return IRQ_NONE;
 	}
 
-	num_left = count - 1;
+	total_pending = T5_msg_count - 1;
+	if (!total_pending)
+		goto end;
 
 	/* Process remaining messages if necessary */
-	if (num_left) {
-		ret = mxt_read_and_process_messages(data, num_left);
+	T5_msg_count = mxt_max_msg_read_count(data, total_pending);
+
+	do {
+		if ((total_pending - total_processed) < T5_msg_count)
+			T5_msg_count = total_pending - total_processed;
+		ret = mxt_read_and_process_messages(data, T5_msg_count);
 		if (ret < 0)
 			goto end;
-		else if (ret != num_left)
-			dev_warn(dev, "Unexpected invalid message\n");
-	}
+		total_processed += T5_msg_count;
+		processed_valid += ret;
+	} while (total_processed < total_pending);
+
+	if (processed_valid != total_pending)
+		dev_warn(dev, "Unexpected invalid message\n");
 
 end:
 	if (data->update_input) {
@@ -1521,9 +1553,10 @@ static int mxt_process_messages_until_invalid(struct mxt_data *data)
 {
 	struct device *dev = &data->client->dev;
 	int count, read;
-	u8 tries = 2;
+	int tries;
 
-	count = data->max_reportid;
+	count = mxt_max_msg_read_count(data, data->max_reportid);
+	tries = (data->max_reportid / count) + 1;
 
 	/* Read messages until we force an invalid */
 	do {
@@ -4110,6 +4143,10 @@ static int mxt_parse_device_properties(struct mxt_data *data)
 	}
 
 	device_property_read_u32(dev, "atmel,suspend-mode", &data->suspend_mode);
+	device_property_read_u32(dev, "atmel,mtu", &data->mtu);
+	if (data->mtu)
+		dev_dbg(dev, "mtu is set as %d\n", data->mtu);
+
 	return 0;
 }
 
-- 
2.19.2

[PATCH v2 37/49] Input: atmel_mxt_ts: Limit the max bytes transferred in an i2c transaction

[Jiada Wang]

From: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com>

In mxt_process_messages_until_invalid() function, driver tries to read
all possible reportid in a single i2c transaction. Number of bytes read
is limited by the max_reportid parameter.
If the max_reportid is a very large value, then a large chunk of bytes
will be requested from the controller in a single i2c transaction.
This transaction can fail due to timeout. This is visible when the
Atmel controller is connected to the SOC via a i2c mux hardware.

mxt_process_messages_t44() reads the T44 message which contains the
pending T5 message count. If the number of pending T5 messages returned
by T44 message is too high then there is a risk of i2c transaction
timeout while reading T5 messages in mxt_process_messages_t44().

New property 'atmel,mtu' is created. This property limits the maximum
number of bytes that can read/transferred in an i2c transcation

Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 .../bindings/input/atmel,maxtouch.txt         |  3 +
 drivers/input/touchscreen/atmel_mxt_ts.c      | 65 +++++++++++++++----
 2 files changed, 54 insertions(+), 14 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
index d7db16920083..62c93d94bc5d 100644
--- a/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
+++ b/Documentation/devicetree/bindings/input/atmel,maxtouch.txt
@@ -42,6 +42,8 @@ Optional properties for main touchpad device:
 
 - atmel,input_name: Override name of input device from the default.
 
+- atmel,mtu: Maximum number of bytes that can read/transferred in an i2c transaction
+
 Example:
 
 	touch@4b {
@@ -49,4 +51,5 @@ Example:
 		reg = <0x4b>;
 		interrupt-parent = <&gpio>;
 		interrupts = <TEGRA_GPIO(W, 3) IRQ_TYPE_LEVEL_LOW>;
+		atmel,mtu = <200>
 	};
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index aa33962ed1dc..169107413823 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -417,6 +417,7 @@ struct mxt_data {
 	/* Indicates whether device is updating configuration */
 	bool updating_config;
 
+	unsigned int mtu;
 	bool t25_status;
 };
 
@@ -1462,11 +1463,32 @@ static int mxt_read_and_process_messages(struct mxt_data *data, u8 count)
 	return num_valid;
 }
 
+static u8 mxt_max_msg_read_count(struct mxt_data *data, u8 max_T5_msg_count)
+{
+	u8 T5_msg_count_limit = data->mtu / data->T5_msg_size;
+
+	if (!data->mtu)
+		return max_T5_msg_count;
+
+	if (data->mtu < data->T5_msg_size) {
+		WARN(1, "mtu set is lesser than the T5 message size\n");
+		/* Return count of 1, as fallback */
+		return 1;
+	}
+	/*
+	 * Return maximum number of T5 messages in single i2c transaction
+	 * based on "atmel,mtu" property.
+	 */
+	return min(T5_msg_count_limit, max_T5_msg_count);
+}
+
 static irqreturn_t mxt_process_messages_t44(struct mxt_data *data)
 {
 	struct device *dev = &data->client->dev;
 	int ret;
-	u8 count, num_left;
+	u8 T5_msg_count, total_pending;
+	u8 total_processed = 0;
+	u8 processed_valid = 0;
 
 	/* Read T44 and T5 together */
 	ret = __mxt_read_reg(data->client, data->T44_address,
@@ -1476,18 +1498,19 @@ static irqreturn_t mxt_process_messages_t44(struct mxt_data *data)
 		return IRQ_NONE;
 	}
 
-	count = data->msg_buf[0];
+	T5_msg_count = data->msg_buf[0];
 
 	/*
 	 * This condition may be caused by the CHG line being configured in
 	 * Mode 0. It results in unnecessary I2C operations but it is benign.
 	 */
-	if (count == 0)
+	if (!T5_msg_count)
 		return IRQ_NONE;
 
-	if (count > data->max_reportid) {
-		dev_warn(dev, "T44 count %d exceeded max report id\n", count);
-		count = data->max_reportid;
+	if (T5_msg_count > data->max_reportid) {
+		dev_warn(dev, "T44 count %d exceeded max report id\n",
+			 T5_msg_count);
+		T5_msg_count = data->max_reportid;
 	}
 
 	/* Process first message */
@@ -1497,16 +1520,25 @@ static irqreturn_t mxt_process_messages_t44(struct mxt_data *data)
 		return IRQ_NONE;
 	}
 
-	num_left = count - 1;
+	total_pending = T5_msg_count - 1;
+	if (!total_pending)
+		goto end;
 
 	/* Process remaining messages if necessary */
-	if (num_left) {
-		ret = mxt_read_and_process_messages(data, num_left);
+	T5_msg_count = mxt_max_msg_read_count(data, total_pending);
+
+	do {
+		if ((total_pending - total_processed) < T5_msg_count)
+			T5_msg_count = total_pending - total_processed;
+		ret = mxt_read_and_process_messages(data, T5_msg_count);
 		if (ret < 0)
 			goto end;
-		else if (ret != num_left)
-			dev_warn(dev, "Unexpected invalid message\n");
-	}
+		total_processed += T5_msg_count;
+		processed_valid += ret;
+	} while (total_processed < total_pending);
+
+	if (processed_valid != total_pending)
+		dev_warn(dev, "Unexpected invalid message\n");
 
 end:
 	if (data->update_input) {
@@ -1521,9 +1553,10 @@ static int mxt_process_messages_until_invalid(struct mxt_data *data)
 {
 	struct device *dev = &data->client->dev;
 	int count, read;
-	u8 tries = 2;
+	int tries;
 
-	count = data->max_reportid;
+	count = mxt_max_msg_read_count(data, data->max_reportid);
+	tries = (data->max_reportid / count) + 1;
 
 	/* Read messages until we force an invalid */
 	do {
@@ -4110,6 +4143,10 @@ static int mxt_parse_device_properties(struct mxt_data *data)
 	}
 
 	device_property_read_u32(dev, "atmel,suspend-mode", &data->suspend_mode);
+	device_property_read_u32(dev, "atmel,mtu", &data->mtu);
+	if (data->mtu)
+		dev_dbg(dev, "mtu is set as %d\n", data->mtu);
+
 	return 0;
 }
 
-- 
2.19.2

[PATCH v2 38/49] Input: atmel_mxt_ts: return error from mxt_process_messages_until_invalid()

[Jiada Wang]

From: Dean Jenkins <Dean_Jenkins@mentor.com>

mxt_process_messages_until_invalid() failed to propagate the error
code from mxt_read_and_process_messages() so return the error code.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Deepak Das <deepak_das@mentor.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 169107413823..e9a895473ed8 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -1561,6 +1561,8 @@ static int mxt_process_messages_until_invalid(struct mxt_data *data)
 	/* Read messages until we force an invalid */
 	do {
 		read = mxt_read_and_process_messages(data, count);
+		if (read < 0)
+			return read;
 		if (read < count)
 			return 0;
 	} while (--tries);
-- 
2.19.2

[PATCH v2 38/49] Input: atmel_mxt_ts: return error from mxt_process_messages_until_invalid()

[Jiada Wang]

From: Dean Jenkins <Dean_Jenkins@mentor.com>

mxt_process_messages_until_invalid() failed to propagate the error
code from mxt_read_and_process_messages() so return the error code.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Deepak Das <deepak_das@mentor.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 169107413823..e9a895473ed8 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -1561,6 +1561,8 @@ static int mxt_process_messages_until_invalid(struct mxt_data *data)
 	/* Read messages until we force an invalid */
 	do {
 		read = mxt_read_and_process_messages(data, count);
+		if (read < 0)
+			return read;
 		if (read < count)
 			return 0;
 	} while (--tries);
-- 
2.19.2

[PATCH v2 39/49] Input: Atmel: improve error handling in mxt_start()

[Jiada Wang]

From: Deepak Das <deepak_das@mentor.com>

mxt_start() does not return error in any of
the failure cases which will allow input_dev->open()
to return success even in case of any failure.

This commit modifies mxt_start() to return error
in failure cases.

Signed-off-by: Deepak Das <deepak_das@mentor.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 31 ++++++++++++------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index e9a895473ed8..dd70f3b9678f 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -3971,12 +3971,13 @@ static int mxt_start(struct mxt_data *data)
 
 	switch (data->suspend_mode) {
 	case MXT_SUSPEND_T9_CTRL:
-		mxt_soft_reset(data);
-
+		ret = mxt_soft_reset(data);
+		if (ret)
+			break;
 		/* Touch enable */
 		/* 0x83 = SCANEN | RPTEN | ENABLE */
-		mxt_write_object(data,
-				MXT_TOUCH_MULTI_T9, MXT_T9_CTRL, 0x83);
+		ret = mxt_write_object(data,
+				       MXT_TOUCH_MULTI_T9, MXT_T9_CTRL, 0x83);
 		break;
 
 	case MXT_SUSPEND_REGULATOR:
@@ -3990,27 +3991,26 @@ static int mxt_start(struct mxt_data *data)
 		 * Discard any touch messages still in message buffer
 		 * from before chip went to sleep
 		 */
-		mxt_process_messages_until_invalid(data);
+		ret = mxt_process_messages_until_invalid(data);
+		if (ret)
+			break;
 
 		ret = mxt_set_t7_power_cfg(data, MXT_POWER_CFG_RUN);
 		if (ret)
-			return ret;
+			break;
 
 		/* Recalibrate since chip has been in deep sleep */
 		ret = mxt_t6_command(data, MXT_COMMAND_CALIBRATE, 1, false);
 		if (ret)
-			return ret;
+			break;
 
 		ret = mxt_acquire_irq(data);
-		if (ret)
-			return ret;
-
-		break;
 	}
 
-	data->suspended = false;
+	if (!ret)
+		data->suspended = false;
 
-	return 0;
+	return ret;
 }
 
 static int mxt_stop(struct mxt_data *data)
@@ -4331,6 +4331,7 @@ static int __maybe_unused mxt_resume(struct device *dev)
 	struct i2c_client *client = to_i2c_client(dev);
 	struct mxt_data *data = i2c_get_clientdata(client);
 	struct input_dev *input_dev = data->input_dev;
+	int ret = 0;
 
 	if (!input_dev)
 		return 0;
@@ -4338,11 +4339,11 @@ static int __maybe_unused mxt_resume(struct device *dev)
 	mutex_lock(&input_dev->mutex);
 
 	if (input_dev->users)
-		mxt_start(data);
+		ret = mxt_start(data);
 
 	mutex_unlock(&input_dev->mutex);
 
-	return 0;
+	return ret;
 }
 
 static SIMPLE_DEV_PM_OPS(mxt_pm_ops, mxt_suspend, mxt_resume);
-- 
2.19.2

[PATCH v2 39/49] Input: Atmel: improve error handling in mxt_start()

[Jiada Wang]

From: Deepak Das <deepak_das@mentor.com>

mxt_start() does not return error in any of
the failure cases which will allow input_dev->open()
to return success even in case of any failure.

This commit modifies mxt_start() to return error
in failure cases.

Signed-off-by: Deepak Das <deepak_das@mentor.com>
Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 31 ++++++++++++------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index e9a895473ed8..dd70f3b9678f 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -3971,12 +3971,13 @@ static int mxt_start(struct mxt_data *data)
 
 	switch (data->suspend_mode) {
 	case MXT_SUSPEND_T9_CTRL:
-		mxt_soft_reset(data);
-
+		ret = mxt_soft_reset(data);
+		if (ret)
+			break;
 		/* Touch enable */
 		/* 0x83 = SCANEN | RPTEN | ENABLE */
-		mxt_write_object(data,
-				MXT_TOUCH_MULTI_T9, MXT_T9_CTRL, 0x83);
+		ret = mxt_write_object(data,
+				       MXT_TOUCH_MULTI_T9, MXT_T9_CTRL, 0x83);
 		break;
 
 	case MXT_SUSPEND_REGULATOR:
@@ -3990,27 +3991,26 @@ static int mxt_start(struct mxt_data *data)
 		 * Discard any touch messages still in message buffer
 		 * from before chip went to sleep
 		 */
-		mxt_process_messages_until_invalid(data);
+		ret = mxt_process_messages_until_invalid(data);
+		if (ret)
+			break;
 
 		ret = mxt_set_t7_power_cfg(data, MXT_POWER_CFG_RUN);
 		if (ret)
-			return ret;
+			break;
 
 		/* Recalibrate since chip has been in deep sleep */
 		ret = mxt_t6_command(data, MXT_COMMAND_CALIBRATE, 1, false);
 		if (ret)
-			return ret;
+			break;
 
 		ret = mxt_acquire_irq(data);
-		if (ret)
-			return ret;
-
-		break;
 	}
 
-	data->suspended = false;
+	if (!ret)
+		data->suspended = false;
 
-	return 0;
+	return ret;
 }
 
 static int mxt_stop(struct mxt_data *data)
@@ -4331,6 +4331,7 @@ static int __maybe_unused mxt_resume(struct device *dev)
 	struct i2c_client *client = to_i2c_client(dev);
 	struct mxt_data *data = i2c_get_clientdata(client);
 	struct input_dev *input_dev = data->input_dev;
+	int ret = 0;
 
 	if (!input_dev)
 		return 0;
@@ -4338,11 +4339,11 @@ static int __maybe_unused mxt_resume(struct device *dev)
 	mutex_lock(&input_dev->mutex);
 
 	if (input_dev->users)
-		mxt_start(data);
+		ret = mxt_start(data);
 
 	mutex_unlock(&input_dev->mutex);
 
-	return 0;
+	return ret;
 }
 
 static SIMPLE_DEV_PM_OPS(mxt_pm_ops, mxt_suspend, mxt_resume);
-- 
2.19.2