diff mbox series

[v12,2/4] Input: add core support for Goodix Berlin Touchscreen IC

Message ID 20231209-topic-goodix-berlin-upstream-initial-v12-2-eaffaeb53fb5@linaro.org (mailing list archive)
State Superseded
Headers show
Series Input: add initial support for Goodix Berlin touchscreen IC | expand

Commit Message

Neil Armstrong Dec. 9, 2023, 7:33 a.m. UTC
Add initial support for the new Goodix "Berlin" touchscreen ICs.

These touchscreen ICs support SPI, I2C and I3C interface, up to
10 finger touch, stylus and gestures events.

This initial driver is derived from the Goodix goodix_ts_berlin
available at [1] and [2] and only supports the GT9916 IC
present on the Qualcomm SM8550 MTP & QRD touch panel.

The current implementation only supports BerlinD, aka GT9916.

Support for advanced features like:
- Firmware & config update
- Stylus events
- Gestures events
- Previous revisions support (BerlinA or BerlinB)
is not included in current version.

The current support will work with currently flashed firmware
and config, and bail out if firmware or config aren't flashed yet.

[1] https://github.com/goodix/goodix_ts_berlin
[2] https://git.codelinaro.org/clo/la/platform/vendor/opensource/touch-drivers

Reviewed-by: Jeff LaBundy <jeff@labundy.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
---
 drivers/input/touchscreen/Kconfig              |   3 +
 drivers/input/touchscreen/Makefile             |   1 +
 drivers/input/touchscreen/goodix_berlin.h      | 159 +++++++
 drivers/input/touchscreen/goodix_berlin_core.c | 595 +++++++++++++++++++++++++
 4 files changed, 758 insertions(+)

Comments

Dmitry Torokhov Dec. 10, 2023, 6:53 a.m. UTC | #1
Hi Neil,

On Sat, Dec 09, 2023 at 08:33:40AM +0100, Neil Armstrong wrote:
> Add initial support for the new Goodix "Berlin" touchscreen ICs.
> 
> These touchscreen ICs support SPI, I2C and I3C interface, up to
> 10 finger touch, stylus and gestures events.
> 
> This initial driver is derived from the Goodix goodix_ts_berlin
> available at [1] and [2] and only supports the GT9916 IC
> present on the Qualcomm SM8550 MTP & QRD touch panel.
> 
> The current implementation only supports BerlinD, aka GT9916.
> 
> Support for advanced features like:
> - Firmware & config update
> - Stylus events
> - Gestures events
> - Previous revisions support (BerlinA or BerlinB)
> is not included in current version.
> 
> The current support will work with currently flashed firmware
> and config, and bail out if firmware or config aren't flashed yet.
> 
> [1] https://github.com/goodix/goodix_ts_berlin
> [2] https://git.codelinaro.org/clo/la/platform/vendor/opensource/touch-drivers
> 
> Reviewed-by: Jeff LaBundy <jeff@labundy.com>
> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>

Thank you for resending the patch. I think there is an issue in how you
read and parse the data in case of more than 2 fingers. It looks like in
that case you are overwriting the checksum form the first 2 and then not
reading the new checksum but use some garbage past the touch data. I
might be mistaken though...

I also believe you are leaking afe_data in case of success. We have the
newfangled __free(kfree) from cleanup.h that should help there.

Another request - we should not have anything in goodix_berlin.h that is
not used by the I2C and SPI sub-drivers, so the only thing it should
contain is goodix_berlin_probe() declaration and dev_pm_ops. All other
defines and definitions should go to goodix_berlin_core.h.

I made a few more cosmetic changes in the attached patch, please
consider applying it.

Thanks.
Neil Armstrong Dec. 11, 2023, 9:31 a.m. UTC | #2
Hi Dmitry,

On 10/12/2023 07:53, Dmitry Torokhov wrote:
> Hi Neil,
> 
> On Sat, Dec 09, 2023 at 08:33:40AM +0100, Neil Armstrong wrote:
>> Add initial support for the new Goodix "Berlin" touchscreen ICs.
>>
>> These touchscreen ICs support SPI, I2C and I3C interface, up to
>> 10 finger touch, stylus and gestures events.
>>
>> This initial driver is derived from the Goodix goodix_ts_berlin
>> available at [1] and [2] and only supports the GT9916 IC
>> present on the Qualcomm SM8550 MTP & QRD touch panel.
>>
>> The current implementation only supports BerlinD, aka GT9916.
>>
>> Support for advanced features like:
>> - Firmware & config update
>> - Stylus events
>> - Gestures events
>> - Previous revisions support (BerlinA or BerlinB)
>> is not included in current version.
>>
>> The current support will work with currently flashed firmware
>> and config, and bail out if firmware or config aren't flashed yet.
>>
>> [1] https://github.com/goodix/goodix_ts_berlin
>> [2] https://git.codelinaro.org/clo/la/platform/vendor/opensource/touch-drivers
>>
>> Reviewed-by: Jeff LaBundy <jeff@labundy.com>
>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
> 
> Thank you for resending the patch. I think there is an issue in how you
> read and parse the data in case of more than 2 fingers. It looks like in
> that case you are overwriting the checksum form the first 2 and then not
> reading the new checksum but use some garbage past the touch data. I
> might be mistaken though...

Sure, let me check again to be sure it's not the case

> 
> I also believe you are leaking afe_data in case of success. We have the
> newfangled __free(kfree) from cleanup.h that should help there.

Indeed, it was added in the meantime, so let's switch to it

> 
> Another request - we should not have anything in goodix_berlin.h that is
> not used by the I2C and SPI sub-drivers, so the only thing it should
> contain is goodix_berlin_probe() declaration and dev_pm_ops. All other
> defines and definitions should go to goodix_berlin_core.h.
> 
> I made a few more cosmetic changes in the attached patch, please
> consider applying it.

Sure, I'll apply it, thanks for the suggestions,

Neil

> 
> Thanks.
>
Neil Armstrong Dec. 12, 2023, 2:43 p.m. UTC | #3
Hi Dmitry,

On 10/12/2023 07:53, Dmitry Torokhov wrote:
> Hi Neil,
> 
> On Sat, Dec 09, 2023 at 08:33:40AM +0100, Neil Armstrong wrote:
>> Add initial support for the new Goodix "Berlin" touchscreen ICs.
>>
>> These touchscreen ICs support SPI, I2C and I3C interface, up to
>> 10 finger touch, stylus and gestures events.
>>
>> This initial driver is derived from the Goodix goodix_ts_berlin
>> available at [1] and [2] and only supports the GT9916 IC
>> present on the Qualcomm SM8550 MTP & QRD touch panel.
>>
>> The current implementation only supports BerlinD, aka GT9916.
>>
>> Support for advanced features like:
>> - Firmware & config update
>> - Stylus events
>> - Gestures events
>> - Previous revisions support (BerlinA or BerlinB)
>> is not included in current version.
>>
>> The current support will work with currently flashed firmware
>> and config, and bail out if firmware or config aren't flashed yet.
>>
>> [1] https://github.com/goodix/goodix_ts_berlin
>> [2] https://git.codelinaro.org/clo/la/platform/vendor/opensource/touch-drivers
>>
>> Reviewed-by: Jeff LaBundy <jeff@labundy.com>
>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
> 
> Thank you for resending the patch. I think there is an issue in how you
> read and parse the data in case of more than 2 fingers. It looks like in
> that case you are overwriting the checksum form the first 2 and then not
> reading the new checksum but use some garbage past the touch data. I
> might be mistaken though...

I carefully inspected the code again, and it's correct, otherwise I would have experimented
checksum errors, which isn't the case.

First read from goodix_berlin_irq() is GOODIX_BERLIN_IRQ_READ_LEN(2) length in memory:

[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN][GOODIX_BERLIN_COOR_DATA_CHECKSUM_SIZE][GOODIX_BERLIN_BYTES_PER_POINT * x]

the pre_buf_len goodix_berlin_touch_handler() get is GOODIX_BERLIN_IRQ_READ_LEN(2), the we complete the
read after the first read, but since the touch checksum is before the touch data, it works because
we complete the data.

I added some comments to clarify the memory layout and re-ordered the items
in the GOODIX_BERLIN_IRQ_READ_LEN() macro to show GOODIX_BERLIN_COOR_DATA_CHECKSUM
is before the GOODIX_BERLIN_BYTES_PER_POINT data.

> 
> I also believe you are leaking afe_data in case of success. We have the
> newfangled __free(kfree) from cleanup.h that should help there.

Indeed it was leaking.

> 
> Another request - we should not have anything in goodix_berlin.h that is
> not used by the I2C and SPI sub-drivers, so the only thing it should
> contain is goodix_berlin_probe() declaration and dev_pm_ops. All other
> defines and definitions should go to goodix_berlin_core.h.
> 
> I made a few more cosmetic changes in the attached patch, please
> consider applying it.
> 
> Thanks.

Thanks,
Neil
Neil Armstrong Dec. 12, 2023, 3:17 p.m. UTC | #4
On 12/12/2023 15:43, Neil Armstrong wrote:
> Hi Dmitry,
> 
> On 10/12/2023 07:53, Dmitry Torokhov wrote:
>> Hi Neil,
>>
>> On Sat, Dec 09, 2023 at 08:33:40AM +0100, Neil Armstrong wrote:
>>> Add initial support for the new Goodix "Berlin" touchscreen ICs.
>>>
>>> These touchscreen ICs support SPI, I2C and I3C interface, up to
>>> 10 finger touch, stylus and gestures events.
>>>
>>> This initial driver is derived from the Goodix goodix_ts_berlin
>>> available at [1] and [2] and only supports the GT9916 IC
>>> present on the Qualcomm SM8550 MTP & QRD touch panel.
>>>
>>> The current implementation only supports BerlinD, aka GT9916.
>>>
>>> Support for advanced features like:
>>> - Firmware & config update
>>> - Stylus events
>>> - Gestures events
>>> - Previous revisions support (BerlinA or BerlinB)
>>> is not included in current version.
>>>
>>> The current support will work with currently flashed firmware
>>> and config, and bail out if firmware or config aren't flashed yet.
>>>
>>> [1] https://github.com/goodix/goodix_ts_berlin
>>> [2] https://git.codelinaro.org/clo/la/platform/vendor/opensource/touch-drivers
>>>
>>> Reviewed-by: Jeff LaBundy <jeff@labundy.com>
>>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
>>
>> Thank you for resending the patch. I think there is an issue in how you
>> read and parse the data in case of more than 2 fingers. It looks like in
>> that case you are overwriting the checksum form the first 2 and then not
>> reading the new checksum but use some garbage past the touch data. I
>> might be mistaken though...
> 
> I carefully inspected the code again, and it's correct, otherwise I would have experimented
> checksum errors, which isn't the case.
> 
> First read from goodix_berlin_irq() is GOODIX_BERLIN_IRQ_READ_LEN(2) length in memory:
> 
> [GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN][GOODIX_BERLIN_COOR_DATA_CHECKSUM_SIZE][GOODIX_BERLIN_BYTES_PER_POINT * x]
> 
> the pre_buf_len goodix_berlin_touch_handler() get is GOODIX_BERLIN_IRQ_READ_LEN(2), the we complete the
> read after the first read, but since the touch checksum is before the touch data, it works because
> we complete the data.
> 
> I added some comments to clarify the memory layout and re-ordered the items
> in the GOODIX_BERLIN_IRQ_READ_LEN() macro to show GOODIX_BERLIN_COOR_DATA_CHECKSUM
> is before the GOODIX_BERLIN_BYTES_PER_POINT data.

Ok I was wrong, the checksun is at the end, but since we check the checksum _after_
reading the missing fingers, the checksum gets read correctly and is always valid.

The first checksum check is for the header, not the finger data, so it may be
confusing.

I've added a big comment explaining what's done and how the finger data is complete
and where is the finger data checksum is all cases.

Neil

> 
>>
>> I also believe you are leaking afe_data in case of success. We have the
>> newfangled __free(kfree) from cleanup.h that should help there.
> 
> Indeed it was leaking.
> 
>>
>> Another request - we should not have anything in goodix_berlin.h that is
>> not used by the I2C and SPI sub-drivers, so the only thing it should
>> contain is goodix_berlin_probe() declaration and dev_pm_ops. All other
>> defines and definitions should go to goodix_berlin_core.h.
>>
>> I made a few more cosmetic changes in the attached patch, please
>> consider applying it.
>>
>> Thanks.
> 
> Thanks,
> Neil
>
diff mbox series

Patch

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index e3e2324547b9..950da599ae1a 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -416,6 +416,9 @@  config TOUCHSCREEN_GOODIX
 	  To compile this driver as a module, choose M here: the
 	  module will be called goodix.
 
+config TOUCHSCREEN_GOODIX_BERLIN_CORE
+	tristate
+
 config TOUCHSCREEN_HIDEEP
 	tristate "HiDeep Touch IC"
 	depends on I2C
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 62bd24f3ac8e..2e2f3e70cd2c 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -47,6 +47,7 @@  obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL)	+= egalax_ts_serial.o
 obj-$(CONFIG_TOUCHSCREEN_EXC3000)	+= exc3000.o
 obj-$(CONFIG_TOUCHSCREEN_FUJITSU)	+= fujitsu_ts.o
 obj-$(CONFIG_TOUCHSCREEN_GOODIX)	+= goodix_ts.o
+obj-$(CONFIG_TOUCHSCREEN_GOODIX_BERLIN_CORE)	+= goodix_berlin_core.o
 obj-$(CONFIG_TOUCHSCREEN_HIDEEP)	+= hideep.o
 obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX)	+= hynitron_cstxxx.o
 obj-$(CONFIG_TOUCHSCREEN_ILI210X)	+= ili210x.o
diff --git a/drivers/input/touchscreen/goodix_berlin.h b/drivers/input/touchscreen/goodix_berlin.h
new file mode 100644
index 000000000000..235f44947a28
--- /dev/null
+++ b/drivers/input/touchscreen/goodix_berlin.h
@@ -0,0 +1,159 @@ 
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Goodix Touchscreen Driver
+ * Copyright (C) 2020 - 2021 Goodix, Inc.
+ * Copyright (C) 2023 Linaro Ltd.
+ *
+ * Based on goodix_berlin_berlin driver.
+ */
+
+#ifndef __GOODIX_BERLIN_H_
+#define __GOODIX_BERLIN_H_
+
+#include <linux/gpio/consumer.h>
+#include <linux/input.h>
+#include <linux/input/touchscreen.h>
+#include <linux/regulator/consumer.h>
+#include <linux/sizes.h>
+
+#define GOODIX_BERLIN_MAX_TOUCH			10
+
+#define GOODIX_BERLIN_NORMAL_RESET_DELAY_MS	100
+
+#define GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN	8
+#define GOODIX_BERLIN_STATUS_OFFSET		0
+#define GOODIX_BERLIN_REQUEST_TYPE_OFFSET	2
+
+#define GOODIX_BERLIN_BYTES_PER_POINT		8
+#define GOODIX_BERLIN_COOR_DATA_CHECKSUM_SIZE	2
+#define GOODIX_BERLIN_COOR_DATA_CHECKSUM_MASK	GENMASK(15, 0)
+
+/* Read n finger events */
+#define GOODIX_BERLIN_IRQ_READ_LEN(n)		(GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN + \
+						 (GOODIX_BERLIN_BYTES_PER_POINT * (n)) + \
+						 GOODIX_BERLIN_COOR_DATA_CHECKSUM_SIZE)
+
+#define GOODIX_BERLIN_TOUCH_EVENT		BIT(7)
+#define GOODIX_BERLIN_REQUEST_EVENT		BIT(6)
+#define GOODIX_BERLIN_TOUCH_COUNT_MASK		GENMASK(3, 0)
+
+#define GOODIX_BERLIN_REQUEST_CODE_RESET	3
+
+#define GOODIX_BERLIN_POINT_TYPE_MASK		GENMASK(3, 0)
+#define GOODIX_BERLIN_POINT_TYPE_STYLUS_HOVER	1
+#define GOODIX_BERLIN_POINT_TYPE_STYLUS		3
+
+#define GOODIX_BERLIN_TOUCH_ID_MASK		GENMASK(7, 4)
+
+#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
+
+struct goodix_berlin_fw_version {
+	u8 rom_pid[6];
+	u8 rom_vid[3];
+	u8 rom_vid_reserved;
+	u8 patch_pid[8];
+	u8 patch_vid[4];
+	u8 patch_vid_reserved;
+	u8 sensor_id;
+	u8 reserved[2];
+	__le16 checksum;
+} __packed;
+
+struct goodix_berlin_ic_info_version {
+	u8 info_customer_id;
+	u8 info_version_id;
+	u8 ic_die_id;
+	u8 ic_version_id;
+	__le32 config_id;
+	u8 config_version;
+	u8 frame_data_customer_id;
+	u8 frame_data_version_id;
+	u8 touch_data_customer_id;
+	u8 touch_data_version_id;
+	u8 reserved[3];
+} __packed;
+
+struct goodix_berlin_ic_info_feature {
+	__le16 freqhop_feature;
+	__le16 calibration_feature;
+	__le16 gesture_feature;
+	__le16 side_touch_feature;
+	__le16 stylus_feature;
+} __packed;
+
+struct goodix_berlin_ic_info_misc {
+	__le32 cmd_addr;
+	__le16 cmd_max_len;
+	__le32 cmd_reply_addr;
+	__le16 cmd_reply_len;
+	__le32 fw_state_addr;
+	__le16 fw_state_len;
+	__le32 fw_buffer_addr;
+	__le16 fw_buffer_max_len;
+	__le32 frame_data_addr;
+	__le16 frame_data_head_len;
+	__le16 fw_attr_len;
+	__le16 fw_log_len;
+	u8 pack_max_num;
+	u8 pack_compress_version;
+	__le16 stylus_struct_len;
+	__le16 mutual_struct_len;
+	__le16 self_struct_len;
+	__le16 noise_struct_len;
+	__le32 touch_data_addr;
+	__le16 touch_data_head_len;
+	__le16 point_struct_len;
+	__le16 reserved1;
+	__le16 reserved2;
+	__le32 mutual_rawdata_addr;
+	__le32 mutual_diffdata_addr;
+	__le32 mutual_refdata_addr;
+	__le32 self_rawdata_addr;
+	__le32 self_diffdata_addr;
+	__le32 self_refdata_addr;
+	__le32 iq_rawdata_addr;
+	__le32 iq_refdata_addr;
+	__le32 im_rawdata_addr;
+	__le16 im_readata_len;
+	__le32 noise_rawdata_addr;
+	__le16 noise_rawdata_len;
+	__le32 stylus_rawdata_addr;
+	__le16 stylus_rawdata_len;
+	__le32 noise_data_addr;
+	__le32 esd_addr;
+} __packed;
+
+struct goodix_berlin_touch_data {
+	u8 id;
+	u8 unused;
+	__le16 x;
+	__le16 y;
+	__le16 w;
+} __packed;
+
+struct goodix_berlin_core {
+	struct device *dev;
+	struct regmap *regmap;
+	struct regulator *avdd;
+	struct regulator *iovdd;
+	struct gpio_desc *reset_gpio;
+	struct touchscreen_properties props;
+	struct goodix_berlin_fw_version fw_version;
+	struct input_dev *input_dev;
+	int irq;
+
+	/* Runtime parameters extracted from IC_INFO buffer  */
+	u32 touch_data_addr;
+};
+
+int goodix_berlin_probe(struct device *dev, int irq, const struct input_id *id,
+			struct regmap *regmap);
+
+extern const struct dev_pm_ops goodix_berlin_pm_ops;
+
+#endif
diff --git a/drivers/input/touchscreen/goodix_berlin_core.c b/drivers/input/touchscreen/goodix_berlin_core.c
new file mode 100644
index 000000000000..c66e2f0c6529
--- /dev/null
+++ b/drivers/input/touchscreen/goodix_berlin_core.c
@@ -0,0 +1,595 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Goodix Touchscreen Driver
+ * Copyright (C) 2020 - 2021 Goodix, Inc.
+ * Copyright (C) 2023 Linaro Ltd.
+ *
+ * Based on goodix_ts_berlin driver.
+ */
+#include <asm/unaligned.h>
+#include <linux/bitfield.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/regmap.h>
+
+#include "goodix_berlin.h"
+
+/*
+ * Goodix "Berlin" Touchscreen IC driver
+ *
+ * This driver is distinct from goodix.c since hardware interface
+ * is different enough to require a new driver.
+ * None of the register address or data structure are close enough
+ * to the previous generations.
+ *
+ * Currently only handles Multitouch events with already
+ * programmed firmware and "config" for "Revision 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)
+ */
+
+static bool goodix_berlin_checksum_valid(const u8 *data, int size)
+{
+	u32 cal_checksum = 0;
+	u16 r_checksum;
+	u32 i;
+
+	if (size < GOODIX_BERLIN_COOR_DATA_CHECKSUM_SIZE)
+		return false;
+
+	for (i = 0; i < size - GOODIX_BERLIN_COOR_DATA_CHECKSUM_SIZE; i++)
+		cal_checksum += data[i];
+
+	r_checksum = get_unaligned_le16(&data[i]);
+
+	return FIELD_GET(GOODIX_BERLIN_COOR_DATA_CHECKSUM_MASK, cal_checksum) == r_checksum;
+}
+
+static bool goodix_berlin_is_dummy_data(struct goodix_berlin_core *cd,
+					const u8 *data, int size)
+{
+	int i;
+
+	/*
+	 * If the device is missing or doesn't respond the buffer
+	 * could be filled with bus default line state, 0x00 or 0xff,
+	 * so declare success the first time we encounter neither.
+	 */
+	for (i = 0; i < size; i++)
+		if (data[i] > 0 && data[i] < 0xff)
+			return false;
+
+	return true;
+}
+
+static int goodix_berlin_dev_confirm(struct goodix_berlin_core *cd)
+{
+	u8 tx_buf[8], rx_buf[8];
+	int retry = 3;
+	int error;
+
+	memset(tx_buf, GOODIX_BERLIN_DEV_CONFIRM_VAL, sizeof(tx_buf));
+	while (retry--) {
+		error = regmap_raw_write(cd->regmap, GOODIX_BERLIN_BOOTOPTION_ADDR, tx_buf,
+					 sizeof(tx_buf));
+		if (error)
+			return error;
+
+		error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_BOOTOPTION_ADDR, rx_buf,
+					sizeof(rx_buf));
+		if (error)
+			return error;
+
+		if (!memcmp(tx_buf, rx_buf, sizeof(tx_buf)))
+			return 0;
+
+		usleep_range(5000, 5100);
+	}
+
+	dev_err(cd->dev, "device confirm failed, rx_buf: %*ph\n", 8, rx_buf);
+
+	return -EINVAL;
+}
+
+static int goodix_berlin_power_on(struct goodix_berlin_core *cd, bool on)
+{
+	int error = 0;
+
+	if (on) {
+		error = regulator_enable(cd->iovdd);
+		if (error) {
+			dev_err(cd->dev, "Failed to enable iovdd: %d\n", error);
+			return error;
+		}
+
+		/* Vendor waits 3ms for IOVDD to settle */
+		usleep_range(3000, 3100);
+
+		error = regulator_enable(cd->avdd);
+		if (error) {
+			dev_err(cd->dev, "Failed to enable avdd: %d\n", error);
+			goto err_iovdd_disable;
+		}
+
+		/* Vendor waits 15ms for IOVDD to settle */
+		usleep_range(15000, 15100);
+
+		gpiod_set_value(cd->reset_gpio, 0);
+
+		/* Vendor waits 4ms for Firmware to initialize */
+		usleep_range(4000, 4100);
+
+		error = goodix_berlin_dev_confirm(cd);
+		if (error)
+			goto err_dev_reset;
+
+		/* Vendor waits 100ms for Firmware to fully boot */
+		msleep(GOODIX_BERLIN_NORMAL_RESET_DELAY_MS);
+
+		return 0;
+	}
+
+err_dev_reset:
+	gpiod_set_value(cd->reset_gpio, 1);
+
+	regulator_disable(cd->avdd);
+
+err_iovdd_disable:
+	regulator_disable(cd->iovdd);
+
+	return error;
+}
+
+static int goodix_berlin_read_version(struct goodix_berlin_core *cd)
+{
+	u8 buf[sizeof(struct goodix_berlin_fw_version)];
+	int error;
+
+	error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_FW_VERSION_INFO_ADDR, buf, sizeof(buf));
+	if (error) {
+		dev_err(cd->dev, "error reading fw version, %d\n", error);
+		return error;
+	}
+
+	if (!goodix_berlin_checksum_valid(buf, sizeof(buf))) {
+		dev_err(cd->dev, "invalid fw version: checksum error\n");
+		return -EINVAL;
+	}
+
+	memcpy(&cd->fw_version, buf, sizeof(cd->fw_version));
+
+	return 0;
+}
+
+/* Only extract necessary data for runtime */
+static int goodix_berlin_convert_ic_info(struct goodix_berlin_core *cd,
+					 const u8 *data, u16 length)
+{
+	struct goodix_berlin_ic_info_misc misc;
+	unsigned int offset = 0;
+	u8 param_num;
+
+	offset += sizeof(__le16); /* length */
+	offset += sizeof(struct goodix_berlin_ic_info_version);
+	offset += sizeof(struct goodix_berlin_ic_info_feature);
+
+	/* IC_INFO Parameters, variable width structure */
+	offset += 4 * sizeof(u8); /* drv_num, sen_num, button_num, force_num */
+
+	if (offset >= length)
+		goto invalid_offset;
+
+	param_num = data[offset++]; /* active_scan_rate_num */
+
+	offset += param_num * sizeof(__le16);
+
+	if (offset >= length)
+		goto invalid_offset;
+
+	param_num = data[offset++]; /* mutual_freq_num*/
+
+	offset += param_num * sizeof(__le16);
+
+	if (offset >= length)
+		goto invalid_offset;
+
+	param_num = data[offset++]; /* self_tx_freq_num */
+
+	offset += param_num * sizeof(__le16);
+
+	if (offset >= length)
+		goto invalid_offset;
+
+	param_num = data[offset++]; /* self_rx_freq_num */
+
+	offset += param_num * sizeof(__le16);
+
+	if (offset >= length)
+		goto invalid_offset;
+
+	param_num = data[offset++]; /* stylus_freq_num */
+
+	offset += param_num * sizeof(__le16);
+
+	if (offset + sizeof(misc) > length)
+		goto invalid_offset;
+
+	/* goodix_berlin_ic_info_misc */
+	memcpy(&misc, &data[offset], sizeof(misc));
+
+	cd->touch_data_addr = le32_to_cpu(misc.touch_data_addr);
+
+	return 0;
+
+invalid_offset:
+	dev_err(cd->dev, "ic_info length is invalid (offset %d length %d)\n",
+		offset, length);
+	return -EINVAL;
+}
+
+static int goodix_berlin_get_ic_info(struct goodix_berlin_core *cd)
+{
+	__le16 length_raw;
+	u8 *afe_data;
+	u16 length;
+	int error;
+
+	afe_data = kzalloc(GOODIX_BERLIN_IC_INFO_MAX_LEN, GFP_KERNEL);
+	if (!afe_data)
+		return -ENOMEM;
+
+	error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_IC_INFO_ADDR,
+				&length_raw, sizeof(length_raw));
+	if (error) {
+		dev_err(cd->dev, "failed get ic info length, %d\n", error);
+		goto free_afe_data;
+	}
+
+	length = le16_to_cpu(length_raw);
+	if (length >= GOODIX_BERLIN_IC_INFO_MAX_LEN) {
+		dev_err(cd->dev, "invalid ic info length %d\n", length);
+		error = -EINVAL;
+		goto free_afe_data;
+	}
+
+	error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_IC_INFO_ADDR,
+				afe_data, length);
+	if (error) {
+		dev_err(cd->dev, "failed get ic info data, %d\n", error);
+		goto free_afe_data;
+	}
+
+	/* check whether the data is valid (ex. bus default values) */
+	if (goodix_berlin_is_dummy_data(cd, afe_data, length)) {
+		dev_err(cd->dev, "fw info data invalid\n");
+		error = -EINVAL;
+		goto free_afe_data;
+	}
+
+	if (!goodix_berlin_checksum_valid(afe_data, length)) {
+		dev_err(cd->dev, "fw info checksum error\n");
+		error = -EINVAL;
+		goto free_afe_data;
+	}
+
+	error = goodix_berlin_convert_ic_info(cd, afe_data, length);
+	if (error)
+		goto free_afe_data;
+
+	/* check some key info */
+	if (!cd->touch_data_addr) {
+		dev_err(cd->dev, "touch_data_addr is null\n");
+		error = -EINVAL;
+		goto free_afe_data;
+	}
+
+	return 0;
+
+free_afe_data:
+	kfree(afe_data);
+
+	return error;
+}
+
+static void goodix_berlin_parse_finger(struct goodix_berlin_core *cd,
+				       const void *buf, int touch_num)
+{
+	const struct goodix_berlin_touch_data *touch_data = buf;
+	int i;
+
+	/* Report finger touches */
+	for (i = 0; i < touch_num; i++) {
+		unsigned int id;
+
+		id = FIELD_GET(GOODIX_BERLIN_TOUCH_ID_MASK, touch_data[i].id);
+
+		if (id >= GOODIX_BERLIN_MAX_TOUCH) {
+			dev_warn_ratelimited(cd->dev, "invalid finger id %d\n", id);
+			continue;
+		}
+
+		input_mt_slot(cd->input_dev, id);
+		input_mt_report_slot_state(cd->input_dev, MT_TOOL_FINGER, true);
+
+		touchscreen_report_pos(cd->input_dev, &cd->props,
+				       __le16_to_cpu(touch_data[i].x),
+				       __le16_to_cpu(touch_data[i].y),
+				       true);
+		input_report_abs(cd->input_dev, ABS_MT_TOUCH_MAJOR,
+				 __le16_to_cpu(touch_data[i].w));
+	}
+
+	input_mt_sync_frame(cd->input_dev);
+	input_sync(cd->input_dev);
+}
+
+static void goodix_berlin_touch_handler(struct goodix_berlin_core *cd,
+					const void *pre_buf, u32 pre_buf_len)
+{
+	u8 buffer[GOODIX_BERLIN_IRQ_READ_LEN(GOODIX_BERLIN_MAX_TOUCH)];
+	u8 point_type, touch_num;
+	int error;
+
+	/* copy pre-data to buffer */
+	memcpy(buffer, pre_buf, pre_buf_len);
+
+	touch_num = FIELD_GET(GOODIX_BERLIN_TOUCH_COUNT_MASK,
+			      buffer[GOODIX_BERLIN_REQUEST_TYPE_OFFSET]);
+
+	if (touch_num > GOODIX_BERLIN_MAX_TOUCH) {
+		dev_warn(cd->dev, "invalid touch num %d\n", touch_num);
+		return;
+	}
+
+	if (touch_num) {
+		/* read more data if more than 2 touch events */
+		if (unlikely(touch_num > 2)) {
+			error = regmap_raw_read(cd->regmap,
+						cd->touch_data_addr + pre_buf_len,
+						&buffer[pre_buf_len],
+						(touch_num - 2) * GOODIX_BERLIN_BYTES_PER_POINT);
+			if (error) {
+				dev_err_ratelimited(cd->dev, "failed to get touch data, %d\n",
+						    error);
+				return;
+			}
+		}
+
+		point_type = FIELD_GET(GOODIX_BERLIN_POINT_TYPE_MASK,
+				       buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN]);
+
+		if (point_type == GOODIX_BERLIN_POINT_TYPE_STYLUS ||
+		    point_type == GOODIX_BERLIN_POINT_TYPE_STYLUS_HOVER) {
+			dev_warn_once(cd->dev, "Stylus event type not handled\n");
+			return;
+		}
+
+		if (!goodix_berlin_checksum_valid(&buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN],
+						  touch_num * GOODIX_BERLIN_BYTES_PER_POINT + 2)) {
+			dev_err(cd->dev, "touch data checksum error, data: %*ph\n",
+				touch_num * GOODIX_BERLIN_BYTES_PER_POINT + 2,
+				&buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN]);
+			return;
+		}
+	}
+
+	goodix_berlin_parse_finger(cd, &buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN],
+				   touch_num);
+}
+
+static int goodix_berlin_request_handle_reset(struct goodix_berlin_core *cd)
+{
+	gpiod_set_value(cd->reset_gpio, 1);
+	usleep_range(2000, 2100);
+	gpiod_set_value(cd->reset_gpio, 0);
+
+	msleep(GOODIX_BERLIN_NORMAL_RESET_DELAY_MS);
+
+	return 0;
+}
+
+static irqreturn_t goodix_berlin_threadirq_func(int irq, void *data)
+{
+	struct goodix_berlin_core *cd = data;
+	u8 buf[GOODIX_BERLIN_IRQ_READ_LEN(2)];
+	u8 event_status;
+	int error;
+
+	/* First, read buffer with space for 2 touch events */
+	error = regmap_raw_read(cd->regmap, cd->touch_data_addr, buf,
+				GOODIX_BERLIN_IRQ_READ_LEN(2));
+	if (error) {
+		dev_err_ratelimited(cd->dev, "failed get event head data, %d\n", error);
+		return IRQ_HANDLED;
+	}
+
+	if (buf[GOODIX_BERLIN_STATUS_OFFSET] == 0)
+		return IRQ_HANDLED;
+
+	if (!goodix_berlin_checksum_valid(buf, GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN)) {
+		dev_warn_ratelimited(cd->dev, "touch head checksum err : %*ph\n",
+				     GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN, buf);
+		return IRQ_HANDLED;
+	}
+
+	event_status = buf[GOODIX_BERLIN_STATUS_OFFSET];
+
+	if (event_status & GOODIX_BERLIN_TOUCH_EVENT)
+		goodix_berlin_touch_handler(cd, buf, GOODIX_BERLIN_IRQ_READ_LEN(2));
+
+	if (event_status & GOODIX_BERLIN_REQUEST_EVENT) {
+		switch (buf[GOODIX_BERLIN_REQUEST_TYPE_OFFSET]) {
+		case GOODIX_BERLIN_REQUEST_CODE_RESET:
+			if (cd->reset_gpio)
+				goodix_berlin_request_handle_reset(cd);
+			break;
+
+		default:
+			dev_warn(cd->dev, "unsupported request code 0x%x\n",
+				 buf[GOODIX_BERLIN_REQUEST_TYPE_OFFSET]);
+		}
+	}
+
+	/* Clear up status field */
+	regmap_write(cd->regmap, cd->touch_data_addr, 0);
+
+	return IRQ_HANDLED;
+}
+
+static int goodix_berlin_input_dev_config(struct goodix_berlin_core *cd,
+					  const struct input_id *id)
+{
+	struct input_dev *input_dev;
+	int error;
+
+	input_dev = devm_input_allocate_device(cd->dev);
+	if (!input_dev)
+		return -ENOMEM;
+
+	cd->input_dev = input_dev;
+	input_set_drvdata(input_dev, cd);
+
+	input_dev->name = "Goodix Berlin Capacitive TouchScreen";
+	input_dev->phys = "input/ts";
+
+	input_dev->id = *id;
+
+	input_set_abs_params(cd->input_dev, ABS_MT_POSITION_X, 0, SZ_64K - 1, 0, 0);
+	input_set_abs_params(cd->input_dev, ABS_MT_POSITION_Y, 0, SZ_64K - 1, 0, 0);
+	input_set_abs_params(cd->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
+
+	touchscreen_parse_properties(cd->input_dev, true, &cd->props);
+
+	error = input_mt_init_slots(cd->input_dev, GOODIX_BERLIN_MAX_TOUCH,
+				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+	if (error)
+		return error;
+
+	error = input_register_device(cd->input_dev);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+static int goodix_berlin_pm_suspend(struct device *dev)
+{
+	struct goodix_berlin_core *cd = dev_get_drvdata(dev);
+
+	disable_irq(cd->irq);
+
+	return goodix_berlin_power_on(cd, false);
+}
+
+static int goodix_berlin_pm_resume(struct device *dev)
+{
+	struct goodix_berlin_core *cd = dev_get_drvdata(dev);
+	int error;
+
+	error = goodix_berlin_power_on(cd, true);
+	if (error)
+		return error;
+
+	enable_irq(cd->irq);
+
+	return 0;
+}
+
+EXPORT_GPL_SIMPLE_DEV_PM_OPS(goodix_berlin_pm_ops,
+			     goodix_berlin_pm_suspend,
+			     goodix_berlin_pm_resume);
+
+static void goodix_berlin_power_off(void *data)
+{
+	struct goodix_berlin_core *cd = data;
+
+	goodix_berlin_power_on(cd, false);
+}
+
+int goodix_berlin_probe(struct device *dev, int irq, const struct input_id *id,
+			struct regmap *regmap)
+{
+	struct goodix_berlin_core *cd;
+	int error;
+
+	if (irq <= 0) {
+		dev_err(dev, "Missing interrupt number\n");
+		return -EINVAL;
+	}
+
+	cd = devm_kzalloc(dev, sizeof(*cd), GFP_KERNEL);
+	if (!cd)
+		return -ENOMEM;
+
+	cd->dev = dev;
+	cd->regmap = regmap;
+	cd->irq = irq;
+
+	cd->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(cd->reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(cd->reset_gpio),
+				     "Failed to request reset gpio\n");
+
+	cd->avdd = devm_regulator_get(dev, "avdd");
+	if (IS_ERR(cd->avdd))
+		return dev_err_probe(dev, PTR_ERR(cd->avdd),
+				     "Failed to request avdd regulator\n");
+
+	cd->iovdd = devm_regulator_get(dev, "iovdd");
+	if (IS_ERR(cd->iovdd))
+		return dev_err_probe(dev, PTR_ERR(cd->iovdd),
+				     "Failed to request iovdd regulator\n");
+
+	error = goodix_berlin_power_on(cd, true);
+	if (error) {
+		dev_err(dev, "failed power on");
+		return error;
+	}
+
+	error = devm_add_action_or_reset(dev, goodix_berlin_power_off, cd);
+	if (error)
+		return error;
+
+	error = goodix_berlin_read_version(cd);
+	if (error) {
+		dev_err(dev, "failed to get version info");
+		return error;
+	}
+
+	error = goodix_berlin_get_ic_info(cd);
+	if (error) {
+		dev_err(dev, "invalid ic info, abort");
+		return error;
+	}
+
+	error = goodix_berlin_input_dev_config(cd, id);
+	if (error) {
+		dev_err(dev, "failed set input device");
+		return error;
+	}
+
+	error = devm_request_threaded_irq(dev, irq, NULL,
+					  goodix_berlin_threadirq_func,
+					  IRQF_ONESHOT, "goodix-berlin", cd);
+	if (error) {
+		dev_err(dev, "request threaded irq failed: %d\n", error);
+		return error;
+	}
+
+	dev_set_drvdata(dev, cd);
+
+	dev_dbg(dev, "Goodix Berlin %s Touchscreen Controller", cd->fw_version.patch_pid);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(goodix_berlin_probe);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Goodix Berlin Core Touchscreen driver");
+MODULE_AUTHOR("Neil Armstrong <neil.armstrong@linaro.org>");