[PATCH v2 09/49] Input: atmel_mxt_ts - implement T15 Key Array support

[Jiada Wang <jiada_wang@mentor.com>]

From: Nick Dyer <nick.dyer@itdev.co.uk>

There is a key array object in many maXTouch chips which allows some X/Y
lines to be used as a key array. This patch maps them to a series of keys
which may be configured in a platform data array.

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Acked-by: Benson Leung <bleung@chromium.org>
Acked-by: Yufeng Shen <miletus@chromium.org>
(cherry picked from ndyer/linux/for-upstream commit 15bb074b5abf3a101f7b79544213f1c110ea4cab)
[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@mentor.com>
[jiada: Fix compilation warning]
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 85 ++++++++++++++++++++++++
 1 file changed, 85 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 68c8237f7932..1d738c488bdd 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -314,6 +314,9 @@ struct mxt_data {
 	struct mxt_dbg dbg;
 	struct gpio_desc *reset_gpio;
 	bool use_retrigen_workaround;
+	unsigned long t15_keystatus;
+	int t15_num_keys;
+	const unsigned int *t15_keymap;
 
 	/* Cached parameters from object table */
 	u16 T5_address;
@@ -324,6 +327,8 @@ struct mxt_data {
 	u16 T71_address;
 	u8 T9_reportid_min;
 	u8 T9_reportid_max;
+	u8 T15_reportid_min;
+	u8 T15_reportid_max;
 	u16 T18_address;
 	u8 T19_reportid;
 	u8 T42_reportid_min;
@@ -987,6 +992,38 @@ static void mxt_proc_t100_message(struct mxt_data *data, u8 *message)
 	data->update_input = true;
 }
 
+static void mxt_proc_t15_messages(struct mxt_data *data, u8 *msg)
+{
+	struct input_dev *input_dev = data->input_dev;
+	struct device *dev = &data->client->dev;
+	int key;
+	bool curr_state, new_state;
+	bool sync = false;
+	unsigned long keystates = le32_to_cpu((__force __le32)msg[2]);
+
+	for (key = 0; key < data->t15_num_keys; key++) {
+		curr_state = test_bit(key, &data->t15_keystatus);
+		new_state = test_bit(key, &keystates);
+
+		if (!curr_state && new_state) {
+			dev_dbg(dev, "T15 key press: %u\n", key);
+			__set_bit(key, &data->t15_keystatus);
+			input_event(input_dev, EV_KEY,
+				    data->t15_keymap[key], 1);
+			sync = true;
+		} else if (curr_state && !new_state) {
+			dev_dbg(dev, "T15 key release: %u\n", key);
+			__clear_bit(key, &data->t15_keystatus);
+			input_event(input_dev, EV_KEY,
+				    data->t15_keymap[key], 0);
+			sync = true;
+		}
+	}
+
+	if (sync)
+		input_sync(input_dev);
+}
+
 static void mxt_proc_t42_messages(struct mxt_data *data, u8 *msg)
 {
 	struct device *dev = &data->client->dev;
@@ -1045,6 +1082,9 @@ 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->T15_reportid_min
+		   && report_id <= data->T15_reportid_max) {
+		mxt_proc_t15_messages(data, message);
 	} else {
 		mxt_dump_message(data, message);
 	}
@@ -1706,6 +1746,8 @@ static void mxt_free_object_table(struct mxt_data *data)
 	data->T71_address = 0;
 	data->T9_reportid_min = 0;
 	data->T9_reportid_max = 0;
+	data->T15_reportid_min = 0;
+	data->T15_reportid_max = 0;
 	data->T18_address = 0;
 	data->T19_reportid = 0;
 	data->T42_reportid_min = 0;
@@ -1784,6 +1826,10 @@ static int mxt_parse_object_table(struct mxt_data *data,
 						object->num_report_ids - 1;
 			data->num_touchids = object->num_report_ids;
 			break;
+		case MXT_TOUCH_KEYARRAY_T15:
+			data->T15_reportid_min = min_id;
+			data->T15_reportid_max = max_id;
+			break;
 		case MXT_SPT_COMMSCONFIG_T18:
 			data->T18_address = object->start_address;
 			break;
@@ -2077,6 +2123,7 @@ static int mxt_initialize_input_device(struct mxt_data *data)
 	int error;
 	unsigned int num_mt_slots;
 	unsigned int mt_flags = 0;
+	int i;
 
 	switch (data->multitouch) {
 	case MXT_TOUCH_MULTI_T9:
@@ -2190,6 +2237,15 @@ static int mxt_initialize_input_device(struct mxt_data *data)
 				     0, 255, 0, 0);
 	}
 
+	/* For T15 Key Array */
+	if (data->T15_reportid_min) {
+		data->t15_keystatus = 0;
+
+		for (i = 0; i < data->t15_num_keys; i++)
+			input_set_capability(input_dev, EV_KEY,
+					data->t15_keymap[i]);
+	}
+
 	input_set_drvdata(input_dev, data);
 
 	error = input_register_device(input_dev);
@@ -3148,8 +3204,10 @@ static void mxt_input_close(struct input_dev *dev)
 static int mxt_parse_device_properties(struct mxt_data *data)
 {
 	static const char keymap_property[] = "linux,gpio-keymap";
+	static const char buttons_property[] = "atmel,key-buttons";
 	struct device *dev = &data->client->dev;
 	u32 *keymap;
+	u32 *buttonmap;
 	int n_keys;
 	int error;
 
@@ -3180,6 +3238,33 @@ static int mxt_parse_device_properties(struct mxt_data *data)
 		data->t19_num_keys = n_keys;
 	}
 
+	if (device_property_present(dev, buttons_property)) {
+		n_keys = device_property_read_u32_array(dev, buttons_property,
+							NULL, 0);
+		if (n_keys <= 0) {
+			error = n_keys < 0 ? n_keys : -EINVAL;
+			dev_err(dev, "invalid/malformed '%s' property: %d\n",
+				buttons_property, error);
+			return error;
+		}
+
+		buttonmap = devm_kmalloc_array(dev, n_keys, sizeof(*buttonmap),
+					       GFP_KERNEL);
+		if (!buttonmap)
+			return -ENOMEM;
+
+		error = device_property_read_u32_array(dev, buttons_property,
+						       buttonmap, n_keys);
+		if (error) {
+			dev_err(dev, "failed to parse '%s' property: %d\n",
+				buttons_property, error);
+			return error;
+		}
+
+		data->t15_keymap = buttonmap;
+		data->t15_num_keys = n_keys;
+	}
+
 	return 0;
 }
 
-- 
2.19.2