Input: edt-ft5x06 - add support for different max support points

Update the code so that the maximum supported points aren't hard coded but
can be changed.

Set the maximum support points based on the data passed along side the
compatible field.
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/edt-ft5x06.c

@@ -38,8 +38,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/input/mt.h>
 #include <linux/input/touchscreen.h>
-
-#define MAX_SUPPORT_POINTS		5
+#include <linux/of_device.h>
 
 #define WORK_REGISTER_THRESHOLD		0x00
 #define WORK_REGISTER_REPORT_RATE	0x08
@@ -105,6 +104,7 @@ struct edt_ft5x06_ts_data {
 	int gain;
 	int offset;
 	int report_rate;
+	int max_support_points;
 
 	char name[EDT_NAME_LEN];
 
@@ -112,6 +112,10 @@ struct edt_ft5x06_ts_data {
 	enum edt_ver version;
 };
 
+struct edt_i2c_chip_data {
+	int  max_support_points;
+};
+
 static int edt_ft5x06_ts_readwrite(struct i2c_client *client,
 				   u16 wr_len, u8 *wr_buf,
 				   u16 rd_len, u8 *rd_buf)
@@ -193,7 +197,7 @@ static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
 	}
 
 	memset(rdbuf, 0, sizeof(rdbuf));
-	datalen = tplen * MAX_SUPPORT_POINTS + offset + crclen;
+	datalen = tplen * tsdata->max_support_points + offset + crclen;
 
 	error = edt_ft5x06_ts_readwrite(tsdata->client,
 					sizeof(cmd), &cmd,
@@ -218,7 +222,7 @@ static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
 			goto out;
 	}
 
-	for (i = 0; i < MAX_SUPPORT_POINTS; i++) {
+	for (i = 0; i < tsdata->max_support_points; i++) {
 		u8 *buf = &rdbuf[i * tplen + offset];
 		bool down;
 
@@ -874,6 +878,7 @@ edt_ft5x06_ts_set_regs(struct edt_ft5x06_ts_data *tsdata)
 static int edt_ft5x06_ts_probe(struct i2c_client *client,
 					 const struct i2c_device_id *id)
 {
+	const struct edt_i2c_chip_data *chip_data;
 	struct edt_ft5x06_ts_data *tsdata;
 	struct input_dev *input;
 	unsigned long irq_flags;
@@ -888,6 +893,16 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
 		return -ENOMEM;
 	}
 
+	chip_data = of_device_get_match_data(&client->dev);
+	if (!chip_data)
+		chip_data = (const struct edt_i2c_chip_data *)id->driver_data;
+	if (!chip_data || !chip_data->max_support_points) {
+		dev_err(&client->dev, "invalid or missing chip data\n");
+		return -EINVAL;
+	}
+
+	tsdata->max_support_points = chip_data->max_support_points;
+
 	tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev,
 						     "reset", GPIOD_OUT_HIGH);
 	if (IS_ERR(tsdata->reset_gpio)) {
@@ -953,7 +968,8 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
 
 	touchscreen_parse_properties(input, true);
 
-	error = input_mt_init_slots(input, MAX_SUPPORT_POINTS, INPUT_MT_DIRECT);
+	error = input_mt_init_slots(input, tsdata->max_support_points,
+				INPUT_MT_DIRECT);
 	if (error) {
 		dev_err(&client->dev, "Unable to init MT slots.\n");
 		return error;
@@ -1032,17 +1048,21 @@ static int __maybe_unused edt_ft5x06_ts_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(edt_ft5x06_ts_pm_ops,
 			 edt_ft5x06_ts_suspend, edt_ft5x06_ts_resume);
 
+static const struct edt_i2c_chip_data edt_ft5x06_data = {
+	.max_support_points = 5,
+};
+
 static const struct i2c_device_id edt_ft5x06_ts_id[] = {
-	{ "edt-ft5x06", 0, },
+	{ .name = "edt-ft5x06", .driver_data = (long)&edt_ft5x06_data },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(i2c, edt_ft5x06_ts_id);
 
 #ifdef CONFIG_OF
 static const struct of_device_id edt_ft5x06_of_match[] = {
-	{ .compatible = "edt,edt-ft5206", },
-	{ .compatible = "edt,edt-ft5306", },
-	{ .compatible = "edt,edt-ft5406", },
+	{ .compatible = "edt,edt-ft5206", .data = &edt_ft5x06_data },
+	{ .compatible = "edt,edt-ft5306", .data = &edt_ft5x06_data },
+	{ .compatible = "edt,edt-ft5406", .data = &edt_ft5x06_data },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, edt_ft5x06_of_match);