Input: goodix - support gt1151 touchpanel

Support was added based on Goodix GitHub repo [1]. There are two major
differences between gt1151 and currently supported devices (gt9x):
 * CONFIG_DATA register has 0x8050 address instead of 0x8047,
 * config data checksum has 16-bit width instead of 8-bit.

Also update goodix_i2c_test() function, so it reads ID register (which
has the same address for all devices) instead of CONFIG_DATA (because
its address is known only after reading ID of the device).

[1] https://github.com/goodix/gt1x_driver_genericSigned-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/goodix.txt

@@ -2,7 +2,8 @@ Device tree bindings for Goodix GT9xx series touchscreen controller
 
 Required properties:
 
- - compatible		: Should be "goodix,gt911"
+ - compatible		: Should be "goodix,gt1151"
+				 or "goodix,gt911"
 				 or "goodix,gt9110"
 				 or "goodix,gt912"
 				 or "goodix,gt927"

drivers/input/touchscreen/goodix.c

@@ -31,9 +31,18 @@
 #include <linux/of.h>
 #include <asm/unaligned.h>
 
+struct goodix_ts_data;
+
+struct goodix_chip_data {
+	u16 config_addr;
+	int config_len;
+	int (*check_config)(struct goodix_ts_data *, const struct firmware *);
+};
+
 struct goodix_ts_data {
 	struct i2c_client *client;
 	struct input_dev *input_dev;
+	const struct goodix_chip_data *chip;
 	int abs_x_max;
 	int abs_y_max;
 	bool swapped_x_y;
@@ -41,7 +50,6 @@ struct goodix_ts_data {
 	bool inverted_y;
 	unsigned int max_touch_num;
 	unsigned int int_trigger_type;
-	int cfg_len;
 	struct gpio_desc *gpiod_int;
 	struct gpio_desc *gpiod_rst;
 	u16 id;
@@ -69,7 +77,8 @@ struct goodix_ts_data {
 #define GOODIX_CMD_SCREEN_OFF		0x05
 
 #define GOODIX_READ_COOR_ADDR		0x814E
-#define GOODIX_REG_CONFIG_DATA		0x8047
+#define GOODIX_GT1X_REG_CONFIG_DATA	0x8050
+#define GOODIX_GT9X_REG_CONFIG_DATA	0x8047
 #define GOODIX_REG_ID			0x8140
 
 #define GOODIX_BUFFER_STATUS_READY	BIT(7)
@@ -79,6 +88,35 @@ struct goodix_ts_data {
 #define MAX_CONTACTS_LOC	5
 #define TRIGGER_LOC		6
 
+static int goodix_check_cfg_8(struct goodix_ts_data *ts,
+			const struct firmware *cfg);
+static int goodix_check_cfg_16(struct goodix_ts_data *ts,
+			const struct firmware *cfg);
+
+static const struct goodix_chip_data gt1x_chip_data = {
+	.config_addr		= GOODIX_GT1X_REG_CONFIG_DATA,
+	.config_len		= GOODIX_CONFIG_MAX_LENGTH,
+	.check_config		= goodix_check_cfg_16,
+};
+
+static const struct goodix_chip_data gt911_chip_data = {
+	.config_addr		= GOODIX_GT9X_REG_CONFIG_DATA,
+	.config_len		= GOODIX_CONFIG_911_LENGTH,
+	.check_config		= goodix_check_cfg_8,
+};
+
+static const struct goodix_chip_data gt967_chip_data = {
+	.config_addr		= GOODIX_GT9X_REG_CONFIG_DATA,
+	.config_len		= GOODIX_CONFIG_967_LENGTH,
+	.check_config		= goodix_check_cfg_8,
+};
+
+static const struct goodix_chip_data gt9x_chip_data = {
+	.config_addr		= GOODIX_GT9X_REG_CONFIG_DATA,
+	.config_len		= GOODIX_CONFIG_MAX_LENGTH,
+	.check_config		= goodix_check_cfg_8,
+};
+
 static const unsigned long goodix_irq_flags[] = {
 	IRQ_TYPE_EDGE_RISING,
 	IRQ_TYPE_EDGE_FALLING,
@@ -177,22 +215,25 @@ static int goodix_i2c_write_u8(struct i2c_client *client, u16 reg, u8 value)
 	return goodix_i2c_write(client, reg, &value, sizeof(value));
 }
 
-static int goodix_get_cfg_len(u16 id)
+static const struct goodix_chip_data *goodix_get_chip_data(u16 id)
 {
 	switch (id) {
+	case 1151:
+		return &gt1x_chip_data;
+
 	case 911:
 	case 9271:
 	case 9110:
 	case 927:
 	case 928:
-		return GOODIX_CONFIG_911_LENGTH;
+		return &gt911_chip_data;
 
 	case 912:
 	case 967:
-		return GOODIX_CONFIG_967_LENGTH;
+		return &gt967_chip_data;
 
 	default:
-		return GOODIX_CONFIG_MAX_LENGTH;
+		return &gt9x_chip_data;
 	}
 }
 
@@ -332,25 +373,12 @@ static int goodix_request_irq(struct goodix_ts_data *ts)
 					 ts->irq_flags, ts->client->name, ts);
 }
 
-/**
- * goodix_check_cfg - Checks if config fw is valid
- *
- * @ts: goodix_ts_data pointer
- * @cfg: firmware config data
- */
-static int goodix_check_cfg(struct goodix_ts_data *ts,
-			    const struct firmware *cfg)
+static int goodix_check_cfg_8(struct goodix_ts_data *ts,
+			const struct firmware *cfg)
 {
-	int i, raw_cfg_len;
+	int i, raw_cfg_len = cfg->size - 2;
 	u8 check_sum = 0;
 
-	if (cfg->size > GOODIX_CONFIG_MAX_LENGTH) {
-		dev_err(&ts->client->dev,
-			"The length of the config fw is not correct");
-		return -EINVAL;
-	}
-
-	raw_cfg_len = cfg->size - 2;
 	for (i = 0; i < raw_cfg_len; i++)
 		check_sum += cfg->data[i];
 	check_sum = (~check_sum) + 1;
@@ -369,6 +397,48 @@ static int goodix_check_cfg(struct goodix_ts_data *ts,
 	return 0;
 }
 
+static int goodix_check_cfg_16(struct goodix_ts_data *ts,
+			const struct firmware *cfg)
+{
+	int i, raw_cfg_len = cfg->size - 3;
+	u16 check_sum = 0;
+
+	for (i = 0; i < raw_cfg_len; i += 2)
+		check_sum += get_unaligned_be16(&cfg->data[i]);
+	check_sum = (~check_sum) + 1;
+	if (check_sum != get_unaligned_be16(&cfg->data[raw_cfg_len])) {
+		dev_err(&ts->client->dev,
+			"The checksum of the config fw is not correct");
+		return -EINVAL;
+	}
+
+	if (cfg->data[raw_cfg_len + 2] != 1) {
+		dev_err(&ts->client->dev,
+			"Config fw must have Config_Fresh register set");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * goodix_check_cfg - Checks if config fw is valid
+ *
+ * @ts: goodix_ts_data pointer
+ * @cfg: firmware config data
+ */
+static int goodix_check_cfg(struct goodix_ts_data *ts,
+			    const struct firmware *cfg)
+{
+	if (cfg->size > GOODIX_CONFIG_MAX_LENGTH) {
+		dev_err(&ts->client->dev,
+			"The length of the config fw is not correct");
+		return -EINVAL;
+	}
+
+	return ts->chip->check_config(ts, cfg);
+}
+
 /**
  * goodix_send_cfg - Write fw config to device
  *
@@ -384,7 +454,7 @@ static int goodix_send_cfg(struct goodix_ts_data *ts,
 	if (error)
 		return error;
 
-	error = goodix_i2c_write(ts->client, GOODIX_REG_CONFIG_DATA, cfg->data,
+	error = goodix_i2c_write(ts->client, ts->chip->config_addr, cfg->data,
 				 cfg->size);
 	if (error) {
 		dev_err(&ts->client->dev, "Failed to write config data: %d",
@@ -511,8 +581,8 @@ static void goodix_read_config(struct goodix_ts_data *ts)
 	u8 config[GOODIX_CONFIG_MAX_LENGTH];
 	int error;
 
-	error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA,
-				config, ts->cfg_len);
+	error = goodix_i2c_read(ts->client, ts->chip->config_addr,
+				config, ts->chip->config_len);
 	if (error) {
 		dev_warn(&ts->client->dev,
 			 "Error reading config (%d), using defaults\n",
@@ -592,7 +662,7 @@ static int goodix_i2c_test(struct i2c_client *client)
 	u8 test;
 
 	while (retry++ < 2) {
-		error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
+		error = goodix_i2c_read(client, GOODIX_REG_ID,
 					&test, 1);
 		if (!error)
 			return 0;
@@ -762,7 +832,7 @@ static int goodix_ts_probe(struct i2c_client *client,
 		return error;
 	}
 
-	ts->cfg_len = goodix_get_cfg_len(ts->id);
+	ts->chip = goodix_get_chip_data(ts->id);
 
 	if (ts->gpiod_int && ts->gpiod_rst) {
 		/* update device config */
@@ -891,6 +961,7 @@ MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
 
 #ifdef CONFIG_OF
 static const struct of_device_id goodix_of_match[] = {
+	{ .compatible = "goodix,gt1151" },
 	{ .compatible = "goodix,gt911" },
 	{ .compatible = "goodix,gt9110" },
 	{ .compatible = "goodix,gt912" },