Input: goodix_berlin - add support for Berlin-A series

The current implementation of the goodix_berlin driver lacks support for
revisions A and B of the Berlin IC. This change adds support for the
gt9897 IC, which is a Berlin-A revision part.

The differences between revision D and A are rather minor, a handful of
address changes and a slightly larger read buffer. They were taken from
the driver published by Goodix, which does a few more things that don't
appear to be necessary for the touchscreen to work properly.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Tested-by: Luca Weiss <luca.weiss@fairphone.com>
Signed-off-by: Jens Reidel <adrian@mainlining.org>
Link: https://lore.kernel.org/r/20250309062315.35720-3-adrian@mainlining.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Author: Gelbpunkt

drivers/input/touchscreen/goodix_berlin.h

@@ -12,12 +12,26 @@
 
 #include <linux/pm.h>
 
+#define GOODIX_BERLIN_FW_VERSION_INFO_ADDR_A	0x1000C
+#define GOODIX_BERLIN_FW_VERSION_INFO_ADDR_D	0x10014
+
+#define GOODIX_BERLIN_IC_INFO_ADDR_A		0x10068
+#define GOODIX_BERLIN_IC_INFO_ADDR_D		0x10070
+
+struct goodix_berlin_ic_data {
+	int fw_version_info_addr;
+	int ic_info_addr;
+	ssize_t read_dummy_len;
+	ssize_t read_prefix_len;
+};
+
 struct device;
 struct input_id;
 struct regmap;
 
 int goodix_berlin_probe(struct device *dev, int irq, const struct input_id *id,
-			struct regmap *regmap);
+			struct regmap *regmap,
+			const struct goodix_berlin_ic_data *ic_data);
 
 extern const struct dev_pm_ops goodix_berlin_pm_ops;
 extern const struct attribute_group *goodix_berlin_groups[];

drivers/input/touchscreen/goodix_berlin_core.c

@@ -12,22 +12,23 @@
  * to the previous generations.
  *
  * Currently the driver only handles Multitouch events with already
- * programmed firmware and "config" for "Revision D" Berlin IC.
+ * programmed firmware and "config" for "Revision A/D" Berlin IC.
  *
  * Support is missing for:
  * - ESD Management
  * - Firmware update/flashing
  * - "Config" update/flashing
  * - Stylus Events
  * - Gesture Events
- * - Support for older revisions (A & B)
+ * - Support for revision B
  */
 
 #include <linux/bitfield.h>
 #include <linux/gpio/consumer.h>
 #include <linux/input.h>
 #include <linux/input/mt.h>
 #include <linux/input/touchscreen.h>
+#include <linux/property.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <linux/sizes.h>
@@ -53,10 +54,8 @@
 
 #define GOODIX_BERLIN_DEV_CONFIRM_VAL		0xAA
 #define GOODIX_BERLIN_BOOTOPTION_ADDR		0x10000
-#define GOODIX_BERLIN_FW_VERSION_INFO_ADDR	0x10014
 
 #define GOODIX_BERLIN_IC_INFO_MAX_LEN		SZ_1K
-#define GOODIX_BERLIN_IC_INFO_ADDR		0x10070
 
 #define GOODIX_BERLIN_CHECKSUM_SIZE		sizeof(u16)
 
@@ -175,6 +174,8 @@ struct goodix_berlin_core {
 	/* Runtime parameters extracted from IC_INFO buffer  */
 	u32 touch_data_addr;
 
+	const struct goodix_berlin_ic_data *ic_data;
+
 	struct goodix_berlin_event event;
 };
 
@@ -299,7 +300,7 @@ static int goodix_berlin_read_version(struct goodix_berlin_core *cd)
 {
 	int error;
 
-	error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_FW_VERSION_INFO_ADDR,
+	error = regmap_raw_read(cd->regmap, cd->ic_data->fw_version_info_addr,
 				&cd->fw_version, sizeof(cd->fw_version));
 	if (error) {
 		dev_err(cd->dev, "error reading fw version, %d\n", error);
@@ -367,7 +368,7 @@ static int goodix_berlin_get_ic_info(struct goodix_berlin_core *cd)
 	if (!afe_data)
 		return -ENOMEM;
 
-	error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_IC_INFO_ADDR,
+	error = regmap_raw_read(cd->regmap, cd->ic_data->ic_info_addr,
 				&length_raw, sizeof(length_raw));
 	if (error) {
 		dev_err(cd->dev, "failed get ic info length, %d\n", error);
@@ -380,8 +381,8 @@ static int goodix_berlin_get_ic_info(struct goodix_berlin_core *cd)
 		return -EINVAL;
 	}
 
-	error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_IC_INFO_ADDR,
-				afe_data, length);
+	error = regmap_raw_read(cd->regmap, cd->ic_data->ic_info_addr, afe_data,
+				length);
 	if (error) {
 		dev_err(cd->dev, "failed get ic info data, %d\n", error);
 		return error;
@@ -716,7 +717,8 @@ const struct attribute_group *goodix_berlin_groups[] = {
 EXPORT_SYMBOL_GPL(goodix_berlin_groups);
 
 int goodix_berlin_probe(struct device *dev, int irq, const struct input_id *id,
-			struct regmap *regmap)
+			struct regmap *regmap,
+			const struct goodix_berlin_ic_data *ic_data)
 {
 	struct goodix_berlin_core *cd;
 	int error;
@@ -733,6 +735,7 @@ int goodix_berlin_probe(struct device *dev, int irq, const struct input_id *id,
 	cd->dev = dev;
 	cd->regmap = regmap;
 	cd->irq = irq;
+	cd->ic_data = ic_data;
 
 	cd->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
 	if (IS_ERR(cd->reset_gpio))

drivers/input/touchscreen/goodix_berlin_i2c.c

@@ -31,6 +31,8 @@ static const struct input_id goodix_berlin_i2c_input_id = {
 
 static int goodix_berlin_i2c_probe(struct i2c_client *client)
 {
+	const struct goodix_berlin_ic_data *ic_data =
+		i2c_get_match_data(client);
 	struct regmap *regmap;
 	int error;
 
@@ -39,22 +41,28 @@ static int goodix_berlin_i2c_probe(struct i2c_client *client)
 		return PTR_ERR(regmap);
 
 	error = goodix_berlin_probe(&client->dev, client->irq,
-				    &goodix_berlin_i2c_input_id, regmap);
+				    &goodix_berlin_i2c_input_id, regmap,
+				    ic_data);
 	if (error)
 		return error;
 
 	return 0;
 }
 
+static const struct goodix_berlin_ic_data gt9916_data = {
+	.fw_version_info_addr = GOODIX_BERLIN_FW_VERSION_INFO_ADDR_D,
+	.ic_info_addr = GOODIX_BERLIN_IC_INFO_ADDR_D,
+};
+
 static const struct i2c_device_id goodix_berlin_i2c_id[] = {
-	{ "gt9916" },
+	{ .name = "gt9916", .driver_data = (long)&gt9916_data },
 	{ }
 };
 
 MODULE_DEVICE_TABLE(i2c, goodix_berlin_i2c_id);
 
 static const struct of_device_id goodix_berlin_i2c_of_match[] = {
-	{ .compatible = "goodix,gt9916", },
+	{ .compatible = "goodix,gt9916", .data = &gt9916_data },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, goodix_berlin_i2c_of_match);

drivers/input/touchscreen/goodix_berlin_spi.c

@@ -18,10 +18,14 @@
 
 #define GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN	1
 #define GOODIX_BERLIN_REGISTER_WIDTH		4
-#define GOODIX_BERLIN_SPI_READ_DUMMY_LEN	3
-#define GOODIX_BERLIN_SPI_READ_PREFIX_LEN	(GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN + \
+#define GOODIX_BERLIN_SPI_READ_DUMMY_LEN_A	4
+#define GOODIX_BERLIN_SPI_READ_DUMMY_LEN_D	3
+#define GOODIX_BERLIN_SPI_READ_PREFIX_LEN_A	(GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN + \
 						 GOODIX_BERLIN_REGISTER_WIDTH + \
-						 GOODIX_BERLIN_SPI_READ_DUMMY_LEN)
+						 GOODIX_BERLIN_SPI_READ_DUMMY_LEN_A)
+#define GOODIX_BERLIN_SPI_READ_PREFIX_LEN_D	(GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN + \
+						 GOODIX_BERLIN_REGISTER_WIDTH + \
+						 GOODIX_BERLIN_SPI_READ_DUMMY_LEN_D)
 #define GOODIX_BERLIN_SPI_WRITE_PREFIX_LEN	(GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN + \
 						 GOODIX_BERLIN_REGISTER_WIDTH)
 
@@ -33,6 +37,7 @@ static int goodix_berlin_spi_read(void *context, const void *reg_buf,
 				  size_t val_size)
 {
 	struct spi_device *spi = context;
+	const struct goodix_berlin_ic_data *ic_data = spi_get_device_match_data(spi);
 	struct spi_transfer xfers;
 	struct spi_message spi_msg;
 	const u32 *reg = reg_buf; /* reg is stored as native u32 at start of buffer */
@@ -42,23 +47,22 @@ static int goodix_berlin_spi_read(void *context, const void *reg_buf,
 		return -EINVAL;
 
 	u8 *buf __free(kfree) =
-		kzalloc(GOODIX_BERLIN_SPI_READ_PREFIX_LEN + val_size,
-			GFP_KERNEL);
+		kzalloc(ic_data->read_prefix_len + val_size, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
 	spi_message_init(&spi_msg);
 	memset(&xfers, 0, sizeof(xfers));
 
-	/* buffer format: 0xF1 + addr(4bytes) + dummy(3bytes) + data */
+	/* buffer format: 0xF1 + addr(4bytes) + dummy(3/4bytes) + data */
 	buf[0] = GOODIX_BERLIN_SPI_READ_FLAG;
 	put_unaligned_be32(*reg, buf + GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN);
 	memset(buf + GOODIX_BERLIN_SPI_TRANS_PREFIX_LEN + GOODIX_BERLIN_REGISTER_WIDTH,
-	       0xff, GOODIX_BERLIN_SPI_READ_DUMMY_LEN);
+	       0xff, ic_data->read_dummy_len);
 
 	xfers.tx_buf = buf;
 	xfers.rx_buf = buf;
-	xfers.len = GOODIX_BERLIN_SPI_READ_PREFIX_LEN + val_size;
+	xfers.len = ic_data->read_prefix_len + val_size;
 	xfers.cs_change = 0;
 	spi_message_add_tail(&xfers, &spi_msg);
 
@@ -68,7 +72,7 @@ static int goodix_berlin_spi_read(void *context, const void *reg_buf,
 		return error;
 	}
 
-	memcpy(val_buf, buf + GOODIX_BERLIN_SPI_READ_PREFIX_LEN, val_size);
+	memcpy(val_buf, buf + ic_data->read_prefix_len, val_size);
 	return error;
 }
 
@@ -123,6 +127,7 @@ static const struct input_id goodix_berlin_spi_input_id = {
 
 static int goodix_berlin_spi_probe(struct spi_device *spi)
 {
+	const struct goodix_berlin_ic_data *ic_data = spi_get_device_match_data(spi);
 	struct regmap_config regmap_config;
 	struct regmap *regmap;
 	size_t max_size;
@@ -137,29 +142,46 @@ static int goodix_berlin_spi_probe(struct spi_device *spi)
 	max_size = spi_max_transfer_size(spi);
 
 	regmap_config = goodix_berlin_spi_regmap_conf;
-	regmap_config.max_raw_read = max_size - GOODIX_BERLIN_SPI_READ_PREFIX_LEN;
+	regmap_config.max_raw_read = max_size - ic_data->read_prefix_len;
 	regmap_config.max_raw_write = max_size - GOODIX_BERLIN_SPI_WRITE_PREFIX_LEN;
 
 	regmap = devm_regmap_init(&spi->dev, NULL, spi, &regmap_config);
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 
 	error = goodix_berlin_probe(&spi->dev, spi->irq,
-				    &goodix_berlin_spi_input_id, regmap);
+				    &goodix_berlin_spi_input_id, regmap,
+				    ic_data);
 	if (error)
 		return error;
 
 	return 0;
 }
 
+static const struct goodix_berlin_ic_data gt9897_data = {
+	.fw_version_info_addr = GOODIX_BERLIN_FW_VERSION_INFO_ADDR_A,
+	.ic_info_addr = GOODIX_BERLIN_IC_INFO_ADDR_A,
+	.read_dummy_len = GOODIX_BERLIN_SPI_READ_DUMMY_LEN_A,
+	.read_prefix_len = GOODIX_BERLIN_SPI_READ_PREFIX_LEN_A,
+};
+
+static const struct goodix_berlin_ic_data gt9916_data = {
+	.fw_version_info_addr = GOODIX_BERLIN_FW_VERSION_INFO_ADDR_D,
+	.ic_info_addr = GOODIX_BERLIN_IC_INFO_ADDR_D,
+	.read_dummy_len = GOODIX_BERLIN_SPI_READ_DUMMY_LEN_D,
+	.read_prefix_len = GOODIX_BERLIN_SPI_READ_PREFIX_LEN_D,
+};
+
 static const struct spi_device_id goodix_berlin_spi_ids[] = {
-	{ "gt9916" },
+	{ .name = "gt9897", .driver_data = (long)&gt9897_data },
+	{ .name = "gt9916", .driver_data = (long)&gt9916_data },
 	{ },
 };
 MODULE_DEVICE_TABLE(spi, goodix_berlin_spi_ids);
 
 static const struct of_device_id goodix_berlin_spi_of_match[] = {
-	{ .compatible = "goodix,gt9916", },
+	{ .compatible = "goodix,gt9897", .data = &gt9897_data },
+	{ .compatible = "goodix,gt9916", .data = &gt9916_data },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, goodix_berlin_spi_of_match);