diff mbox series

[v7,3/3] Input: add driver for the Hycon HY46XX touchpanel series

Message ID 20210413144446.2277817-4-giulio.benetti@benettiengineering.com (mailing list archive)
State Accepted
Commit aa2f62cf211a0985c14fd78a17d55296769698d6
Headers show
Series Input: add Hycon HY46XX Touchscreen controller | expand

Commit Message

Giulio Benetti April 13, 2021, 2:44 p.m. UTC
This patch adds support for Hycon HY46XX.

Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
---
V1->V2:
* removed proximity-sensor-switch property according to previous patch
As suggested by Dmitry Torokhov
* moved i2c communaction to regmap use
* added macro to avoid magic number
* removed cmd variable that could uninitiliazed since we're using regmap now
* removed useless byte masking
* removed useless struct hycon_hy46xx_i2c_chip_data
* used IRQF_ONESHOT only for isr
V2->V3:
As suggested by Jonathan Neuschäfer:
* fixed Kconfig description
* fixed DT properties by preprending "hycon,"
* changed MODULE_AUTHOR() e-mail according to SoB and authorship
V4->V5:
As suggested by Rob Herring according to dt-bindings:
* drop hycon- prefix from compatible
* change hycon,power-noise-enable property name to hycon,noise-filter-enable
  and change power_noise_enable variable name to noise_filter_enable
V5->V6:
* changed report-speed property name into report-speed-hz according to
Rob Herring's suggestion
---
 MAINTAINERS                              |   1 +
 drivers/input/touchscreen/Kconfig        |  11 +
 drivers/input/touchscreen/Makefile       |   1 +
 drivers/input/touchscreen/hycon-hy46xx.c | 591 +++++++++++++++++++++++
 4 files changed, 604 insertions(+)
 create mode 100644 drivers/input/touchscreen/hycon-hy46xx.c

Comments

Dmitry Torokhov April 14, 2021, 5:44 a.m. UTC | #1
Hi Giulio,

On Tue, Apr 13, 2021 at 04:44:46PM +0200, Giulio Benetti wrote:
> +
> +	input_mt_report_pointer_emulation(tsdata->input, true);

For touchscreens it does not make much sense to report BTN_DOUBLETAP,
BTN_TRIPLETAP, etc, events (they are really for touchpads), so I changed
this to

	input_mt_report_pointer_emulation(tsdata->input, false);

to only report ABS_X, ABS_Y, and BTN_TOUCH, and applied.

Thanks.
Peter Hutterer April 14, 2021, 6:46 a.m. UTC | #2
On Tue, Apr 13, 2021 at 10:44:07PM -0700, Dmitry Torokhov wrote:
> Hi Giulio,
> 
> On Tue, Apr 13, 2021 at 04:44:46PM +0200, Giulio Benetti wrote:
> > +
> > +	input_mt_report_pointer_emulation(tsdata->input, true);
> 
> For touchscreens it does not make much sense to report BTN_DOUBLETAP,
> BTN_TRIPLETAP, etc, events (they are really for touchpads), so I changed
> this to
> 
> 	input_mt_report_pointer_emulation(tsdata->input, false);
> 
> to only report ABS_X, ABS_Y, and BTN_TOUCH, and applied.

Can you expand on this please, just to make sure I'm not misinterpreting
those codes? Those bits are just for how many fingers are down (but without
position), dropping those bits means you restrict the device to a pure
single-touch screen. Or am I missing something here?

then again, MT support has been in the kernel for long enough that by now
everything should understand it, so there's a certain "meh" factor.

Cheers,
   Peter
Giulio Benetti April 14, 2021, 11:22 a.m. UTC | #3
Hi Peter, Dmitry,

On 4/14/21 8:46 AM, Peter Hutterer wrote:
> On Tue, Apr 13, 2021 at 10:44:07PM -0700, Dmitry Torokhov wrote:
>> Hi Giulio,
>>
>> On Tue, Apr 13, 2021 at 04:44:46PM +0200, Giulio Benetti wrote:
>>> +
>>> +	input_mt_report_pointer_emulation(tsdata->input, true);
>>
>> For touchscreens it does not make much sense to report BTN_DOUBLETAP,
>> BTN_TRIPLETAP, etc, events (they are really for touchpads), so I changed
>> this to
>>
>> 	input_mt_report_pointer_emulation(tsdata->input, false);
>>
>> to only report ABS_X, ABS_Y, and BTN_TOUCH, and applied.
> 
> Can you expand on this please, just to make sure I'm not misinterpreting
> those codes? Those bits are just for how many fingers are down (but without
> position), dropping those bits means you restrict the device to a pure
> single-touch screen. Or am I missing something here?

I've re-tested the driver after setting 
input_mt_report_pointer_emulation() use_count to false. It works 
correctly with all touch points expected. That use_count refers to 
finger count of Touchpad[1]. Also you can see that even with 
use_count=false this for loop[2] is entered by counting all the 
mt->slots and then input_event() reports all of them.

I hope I've understood correctly :-)

[1]: 
https://elixir.bootlin.com/linux/v5.12-rc7/source/drivers/input/input-mt.c#L190
[2]: 
https://elixir.bootlin.com/linux/v5.12-rc7/source/drivers/input/input-mt.c#L208

> then again, MT support has been in the kernel for long enough that by now
> everything should understand it, so there's a certain "meh" factor.
> 
> Cheers,
>     Peter
> 

Best regards
Giulio Benetti April 14, 2021, 11:24 a.m. UTC | #4
On 4/14/21 7:44 AM, Dmitry Torokhov wrote:
> Hi Giulio,
> 
> On Tue, Apr 13, 2021 at 04:44:46PM +0200, Giulio Benetti wrote:
>> +
>> +	input_mt_report_pointer_emulation(tsdata->input, true);
> 
> For touchscreens it does not make much sense to report BTN_DOUBLETAP,
> BTN_TRIPLETAP, etc, events (they are really for touchpads), so I changed
> this to
> 
> 	input_mt_report_pointer_emulation(tsdata->input, false);
> 
> to only report ABS_X, ABS_Y, and BTN_TOUCH, and applied.
> 
> Thanks.
> 

Thank you, I've re-tested and it works correctly, I've answered to Peter 
Hutterer with what I've understood about that. Please correct me if I'm 
wrong.

Thanks a lot for reviewing
Best regards
Dmitry Torokhov April 14, 2021, 5:26 p.m. UTC | #5
Hi Giulio, Peter,

On Wed, Apr 14, 2021 at 01:22:55PM +0200, Giulio Benetti wrote:
> Hi Peter, Dmitry,
> 
> On 4/14/21 8:46 AM, Peter Hutterer wrote:
> > On Tue, Apr 13, 2021 at 10:44:07PM -0700, Dmitry Torokhov wrote:
> > > Hi Giulio,
> > > 
> > > On Tue, Apr 13, 2021 at 04:44:46PM +0200, Giulio Benetti wrote:
> > > > +
> > > > +	input_mt_report_pointer_emulation(tsdata->input, true);
> > > 
> > > For touchscreens it does not make much sense to report BTN_DOUBLETAP,
> > > BTN_TRIPLETAP, etc, events (they are really for touchpads), so I changed
> > > this to
> > > 
> > > 	input_mt_report_pointer_emulation(tsdata->input, false);
> > > 
> > > to only report ABS_X, ABS_Y, and BTN_TOUCH, and applied.
> > 
> > Can you expand on this please, just to make sure I'm not misinterpreting
> > those codes? Those bits are just for how many fingers are down (but without
> > position), dropping those bits means you restrict the device to a pure
> > single-touch screen. Or am I missing something here?

They are indeed represent number of fingers on the surface. I think I
over-simplified this a bit by saying these events are only for
touchpads, as there is allowance for BTN_TOOL_*TAP in
Documentation/input/multi-touch-protocol.rst for MT devices that may
report more contacts than what they can distinctly track, and it is
not restricted to touchpads (but I believe in reality only used by a
couple of "semi-MT" touchpad drivers).

What I meant to say that for ST fallback of MT-capable devices we
typically provide BTN_TOOL_*TAP for devices declared as INPUT_MT_POINTER
(which is touchpads) and for INPUT_MT_DIRECT and others we only provide
ABS_X, ABS_Y, ABS_PRESSURE and BTN_TOUCH (see input_mt_sync_frame()),
and I think this driver should follow the suit.

> 
> I've re-tested the driver after setting input_mt_report_pointer_emulation()
> use_count to false. It works correctly with all touch points expected. That
> use_count refers to finger count of Touchpad[1]. Also you can see that even
> with use_count=false this for loop[2] is entered by counting all the
> mt->slots and then input_event() reports all of them.

That is not quite true. The loop in question locates the oldest contact
still on the surface and MT->ST mapping uses it as the "primary" point
for ST events. It is reported in addition to sending all contacts via MT
protocol as ABS_MT_SLOT, ABS_MT_POSITION_X, ABS_MT_POSITION_Y, ...

> 
> I hope I've understood correctly :-)
> 
> [1]: https://elixir.bootlin.com/linux/v5.12-rc7/source/drivers/input/input-mt.c#L190
> [2]: https://elixir.bootlin.com/linux/v5.12-rc7/source/drivers/input/input-mt.c#L208
> 
> > then again, MT support has been in the kernel for long enough that by now
> > everything should understand it, so there's a certain "meh" factor.

Yeah, there is that too.

Thanks.
Peter Hutterer April 15, 2021, 6:16 a.m. UTC | #6
On Wed, Apr 14, 2021 at 10:26:13AM -0700, Dmitry Torokhov wrote:
> Hi Giulio, Peter,
> 
> On Wed, Apr 14, 2021 at 01:22:55PM +0200, Giulio Benetti wrote:
> > Hi Peter, Dmitry,
> > 
> > On 4/14/21 8:46 AM, Peter Hutterer wrote:
> > > On Tue, Apr 13, 2021 at 10:44:07PM -0700, Dmitry Torokhov wrote:
> > > > Hi Giulio,
> > > > 
> > > > On Tue, Apr 13, 2021 at 04:44:46PM +0200, Giulio Benetti wrote:
> > > > > +
> > > > > +	input_mt_report_pointer_emulation(tsdata->input, true);
> > > > 
> > > > For touchscreens it does not make much sense to report BTN_DOUBLETAP,
> > > > BTN_TRIPLETAP, etc, events (they are really for touchpads), so I changed
> > > > this to
> > > > 
> > > > 	input_mt_report_pointer_emulation(tsdata->input, false);
> > > > 
> > > > to only report ABS_X, ABS_Y, and BTN_TOUCH, and applied.
> > > 
> > > Can you expand on this please, just to make sure I'm not misinterpreting
> > > those codes? Those bits are just for how many fingers are down (but without
> > > position), dropping those bits means you restrict the device to a pure
> > > single-touch screen. Or am I missing something here?
> 
> They are indeed represent number of fingers on the surface. I think I
> over-simplified this a bit by saying these events are only for
> touchpads, as there is allowance for BTN_TOOL_*TAP in
> Documentation/input/multi-touch-protocol.rst for MT devices that may
> report more contacts than what they can distinctly track, and it is
> not restricted to touchpads (but I believe in reality only used by a
> couple of "semi-MT" touchpad drivers).

fwiw, almost all touchpads on ps2 use that functionality - they can track 2
touchpoints but *detect* up to 5. There's significant insanity in libinput
to deal with that because it is so common :)

semi-mt is orthogonal to that, it's the an inability to track two
touchpoints correctly (only get top-left and bottom-right, but it's
guesswork which finger is in which corner).

> What I meant to say that for ST fallback of MT-capable devices we
> typically provide BTN_TOOL_*TAP for devices declared as INPUT_MT_POINTER
> (which is touchpads) and for INPUT_MT_DIRECT and others we only provide
> ABS_X, ABS_Y, ABS_PRESSURE and BTN_TOUCH (see input_mt_sync_frame()),
> and I think this driver should follow the suit.

ah, right. that makes sense, thanks for the clarification.

Cheers,
   Peter
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 18a50942c019..588ca21cfc09 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8255,6 +8255,7 @@  M:	Giulio Benetti <giulio.benetti@benettiengineering.com>
 L:	linux-input@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/input/touchscreen/hycon,hy46xx.yaml
+F:	drivers/input/touchscreen/hy46xx.c
 
 HYGON PROCESSOR SUPPORT
 M:	Pu Wen <puwen@hygon.cn>
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 529614d364fe..fe1468b74530 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -1335,4 +1335,15 @@  config TOUCHSCREEN_ZINITIX
 	  To compile this driver as a module, choose M here: the
 	  module will be called zinitix.
 
+config TOUCHSCREEN_HYCON_HY46XX
+	tristate "Hycon hy46xx touchscreen support"
+	depends on I2C
+	help
+	  Say Y here if you have a touchscreen using Hycon hy46xx
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called hycon-hy46xx.
+
 endif
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 6233541e9173..8b68cf3a3e6d 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -112,3 +112,4 @@  obj-$(CONFIG_TOUCHSCREEN_ROHM_BU21023)	+= rohm_bu21023.o
 obj-$(CONFIG_TOUCHSCREEN_RASPBERRYPI_FW)	+= raspberrypi-ts.o
 obj-$(CONFIG_TOUCHSCREEN_IQS5XX)	+= iqs5xx.o
 obj-$(CONFIG_TOUCHSCREEN_ZINITIX)	+= zinitix.o
+obj-$(CONFIG_TOUCHSCREEN_HYCON_HY46XX)	+= hycon-hy46xx.o
diff --git a/drivers/input/touchscreen/hycon-hy46xx.c b/drivers/input/touchscreen/hycon-hy46xx.c
new file mode 100644
index 000000000000..4afc88dd0293
--- /dev/null
+++ b/drivers/input/touchscreen/hycon-hy46xx.c
@@ -0,0 +1,591 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021
+ * Author(s): Giulio Benetti <giulio.benetti@benettiengineering.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/irq.h>
+#include <linux/regulator/consumer.h>
+#include <linux/regmap.h>
+
+#include <asm/unaligned.h>
+
+#define HY46XX_CHKSUM_CODE		0x1
+#define HY46XX_FINGER_NUM		0x2
+#define HY46XX_CHKSUM_LEN		0x7
+#define HY46XX_THRESHOLD		0x80
+#define HY46XX_GLOVE_EN			0x84
+#define HY46XX_REPORT_SPEED		0x88
+#define HY46XX_PWR_NOISE_EN		0x89
+#define HY46XX_FILTER_DATA		0x8A
+#define HY46XX_GAIN			0x92
+#define HY46XX_EDGE_OFFSET		0x93
+#define HY46XX_RX_NR_USED		0x94
+#define HY46XX_TX_NR_USED		0x95
+#define HY46XX_PWR_MODE			0xA5
+#define HY46XX_FW_VERSION		0xA6
+#define HY46XX_LIB_VERSION		0xA7
+#define HY46XX_TP_INFO			0xA8
+#define HY46XX_TP_CHIP_ID		0xA9
+#define HY46XX_BOOT_VER			0xB0
+
+#define HY46XX_TPLEN			0x6
+#define HY46XX_REPORT_PKT_LEN		0x44
+
+#define HY46XX_MAX_SUPPORTED_POINTS	11
+
+#define TOUCH_EVENT_DOWN		0x00
+#define TOUCH_EVENT_UP			0x01
+#define TOUCH_EVENT_CONTACT		0x02
+#define TOUCH_EVENT_RESERVED		0x03
+
+struct hycon_hy46xx_data {
+	struct i2c_client *client;
+	struct input_dev *input;
+	struct touchscreen_properties prop;
+	struct regulator *vcc;
+
+	struct gpio_desc *reset_gpio;
+
+	struct mutex mutex;
+	struct regmap *regmap;
+
+	int threshold;
+	bool glove_enable;
+	int report_speed;
+	bool noise_filter_enable;
+	int filter_data;
+	int gain;
+	int edge_offset;
+	int rx_number_used;
+	int tx_number_used;
+	int power_mode;
+	int fw_version;
+	int lib_version;
+	int tp_information;
+	int tp_chip_id;
+	int bootloader_version;
+};
+
+static const struct regmap_config hycon_hy46xx_i2c_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+};
+
+static bool hycon_hy46xx_check_checksum(struct hycon_hy46xx_data *tsdata, u8 *buf)
+{
+	u8 chksum = 0;
+	int i;
+
+	for (i = 2; i < buf[HY46XX_CHKSUM_LEN]; i++)
+		chksum += buf[i];
+
+	if (chksum == buf[HY46XX_CHKSUM_CODE])
+		return true;
+
+	dev_err_ratelimited(&tsdata->client->dev,
+			    "checksum error: 0x%02x expected, got 0x%02x\n",
+			    chksum, buf[HY46XX_CHKSUM_CODE]);
+
+	return false;
+}
+
+static irqreturn_t hycon_hy46xx_isr(int irq, void *dev_id)
+{
+	struct hycon_hy46xx_data *tsdata = dev_id;
+	struct device *dev = &tsdata->client->dev;
+	u8 rdbuf[HY46XX_REPORT_PKT_LEN];
+	int i, x, y, id;
+	int error;
+
+	memset(rdbuf, 0, sizeof(rdbuf));
+
+	error = regmap_bulk_read(tsdata->regmap, 0, rdbuf, sizeof(rdbuf));
+	if (error) {
+		dev_err_ratelimited(dev, "Unable to fetch data, error: %d\n",
+				    error);
+		goto out;
+	}
+
+	if (!hycon_hy46xx_check_checksum(tsdata, rdbuf))
+		goto out;
+
+	for (i = 0; i < HY46XX_MAX_SUPPORTED_POINTS; i++) {
+		u8 *buf = &rdbuf[3 + (HY46XX_TPLEN * i)];
+		int type = buf[0] >> 6;
+
+		if (type == TOUCH_EVENT_RESERVED)
+			continue;
+
+		x = get_unaligned_be16(buf) & 0x0fff;
+		y = get_unaligned_be16(buf + 2) & 0x0fff;
+
+		id = buf[2] >> 4;
+
+		input_mt_slot(tsdata->input, id);
+		if (input_mt_report_slot_state(tsdata->input, MT_TOOL_FINGER,
+					       type != TOUCH_EVENT_UP))
+			touchscreen_report_pos(tsdata->input, &tsdata->prop,
+					       x, y, true);
+	}
+
+	input_mt_report_pointer_emulation(tsdata->input, true);
+	input_sync(tsdata->input);
+
+out:
+	return IRQ_HANDLED;
+}
+
+struct hycon_hy46xx_attribute {
+	struct device_attribute dattr;
+	size_t field_offset;
+	u8 address;
+	u8 limit_low;
+	u8 limit_high;
+};
+
+#define HYCON_ATTR_U8(_field, _mode, _address, _limit_low, _limit_high)	\
+	struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = {		\
+		.dattr = __ATTR(_field, _mode,				\
+				hycon_hy46xx_setting_show,			\
+				hycon_hy46xx_setting_store),			\
+		.field_offset = offsetof(struct hycon_hy46xx_data, _field),	\
+		.address = _address,					\
+		.limit_low = _limit_low,				\
+		.limit_high = _limit_high,				\
+	}
+
+#define HYCON_ATTR_BOOL(_field, _mode, _address)			\
+	struct hycon_hy46xx_attribute hycon_hy46xx_attr_##_field = {		\
+		.dattr = __ATTR(_field, _mode,				\
+				hycon_hy46xx_setting_show,			\
+				hycon_hy46xx_setting_store),			\
+		.field_offset = offsetof(struct hycon_hy46xx_data, _field),	\
+		.address = _address,					\
+		.limit_low = false,					\
+		.limit_high = true,					\
+	}
+
+static ssize_t hycon_hy46xx_setting_show(struct device *dev,
+				   struct device_attribute *dattr, char *buf)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client);
+	struct hycon_hy46xx_attribute *attr =
+			container_of(dattr, struct hycon_hy46xx_attribute, dattr);
+	u8 *field = (u8 *)tsdata + attr->field_offset;
+	size_t count = 0;
+	int error = 0;
+	int val;
+
+	mutex_lock(&tsdata->mutex);
+
+	error = regmap_read(tsdata->regmap, attr->address, &val);
+	if (error < 0) {
+		dev_err(&tsdata->client->dev,
+			"Failed to fetch attribute %s, error %d\n",
+			dattr->attr.name, error);
+		goto out;
+	}
+
+	if (val != *field) {
+		dev_warn(&tsdata->client->dev,
+			 "%s: read (%d) and stored value (%d) differ\n",
+			 dattr->attr.name, val, *field);
+		*field = val;
+	}
+
+	count = scnprintf(buf, PAGE_SIZE, "%d\n", val);
+
+out:
+	mutex_unlock(&tsdata->mutex);
+	return error ?: count;
+}
+
+static ssize_t hycon_hy46xx_setting_store(struct device *dev,
+					struct device_attribute *dattr,
+					const char *buf, size_t count)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct hycon_hy46xx_data *tsdata = i2c_get_clientdata(client);
+	struct hycon_hy46xx_attribute *attr =
+			container_of(dattr, struct hycon_hy46xx_attribute, dattr);
+	u8 *field = (u8 *)tsdata + attr->field_offset;
+	unsigned int val;
+	int error;
+
+	mutex_lock(&tsdata->mutex);
+
+	error = kstrtouint(buf, 0, &val);
+	if (error)
+		goto out;
+
+	if (val < attr->limit_low || val > attr->limit_high) {
+		error = -ERANGE;
+		goto out;
+	}
+
+	error = regmap_write(tsdata->regmap, attr->address, val);
+	if (error < 0) {
+		dev_err(&tsdata->client->dev,
+			"Failed to update attribute %s, error: %d\n",
+			dattr->attr.name, error);
+		goto out;
+	}
+	*field = val;
+
+out:
+	mutex_unlock(&tsdata->mutex);
+	return error ?: count;
+}
+
+static HYCON_ATTR_U8(threshold, 0644, HY46XX_THRESHOLD, 0, 255);
+static HYCON_ATTR_BOOL(glove_enable, 0644, HY46XX_GLOVE_EN);
+static HYCON_ATTR_U8(report_speed, 0644, HY46XX_REPORT_SPEED, 0, 255);
+static HYCON_ATTR_BOOL(noise_filter_enable, 0644, HY46XX_PWR_NOISE_EN);
+static HYCON_ATTR_U8(filter_data, 0644, HY46XX_FILTER_DATA, 0, 5);
+static HYCON_ATTR_U8(gain, 0644, HY46XX_GAIN, 0, 5);
+static HYCON_ATTR_U8(edge_offset, 0644, HY46XX_EDGE_OFFSET, 0, 5);
+static HYCON_ATTR_U8(fw_version, 0444, HY46XX_FW_VERSION, 0, 255);
+static HYCON_ATTR_U8(lib_version, 0444, HY46XX_LIB_VERSION, 0, 255);
+static HYCON_ATTR_U8(tp_information, 0444, HY46XX_TP_INFO, 0, 255);
+static HYCON_ATTR_U8(tp_chip_id, 0444, HY46XX_TP_CHIP_ID, 0, 255);
+static HYCON_ATTR_U8(bootloader_version, 0444, HY46XX_BOOT_VER, 0, 255);
+
+static struct attribute *hycon_hy46xx_attrs[] = {
+	&hycon_hy46xx_attr_threshold.dattr.attr,
+	&hycon_hy46xx_attr_glove_enable.dattr.attr,
+	&hycon_hy46xx_attr_report_speed.dattr.attr,
+	&hycon_hy46xx_attr_noise_filter_enable.dattr.attr,
+	&hycon_hy46xx_attr_filter_data.dattr.attr,
+	&hycon_hy46xx_attr_gain.dattr.attr,
+	&hycon_hy46xx_attr_edge_offset.dattr.attr,
+	&hycon_hy46xx_attr_fw_version.dattr.attr,
+	&hycon_hy46xx_attr_lib_version.dattr.attr,
+	&hycon_hy46xx_attr_tp_information.dattr.attr,
+	&hycon_hy46xx_attr_tp_chip_id.dattr.attr,
+	&hycon_hy46xx_attr_bootloader_version.dattr.attr,
+	NULL
+};
+
+static const struct attribute_group hycon_hy46xx_attr_group = {
+	.attrs = hycon_hy46xx_attrs,
+};
+
+static void hycon_hy46xx_get_defaults(struct device *dev, struct hycon_hy46xx_data *tsdata)
+{
+	bool val_bool;
+	int error;
+	u32 val;
+
+	error = device_property_read_u32(dev, "hycon,threshold", &val);
+	if (!error) {
+		error = regmap_write(tsdata->regmap, HY46XX_THRESHOLD, val);
+		if (error < 0)
+			goto out;
+
+		tsdata->threshold = val;
+	}
+
+	val_bool = device_property_read_bool(dev, "hycon,glove-enable");
+	error = regmap_write(tsdata->regmap, HY46XX_GLOVE_EN, val_bool);
+	if (error < 0)
+		goto out;
+	tsdata->glove_enable = val_bool;
+
+	error = device_property_read_u32(dev, "hycon,report-speed-hz", &val);
+	if (!error) {
+		error = regmap_write(tsdata->regmap, HY46XX_REPORT_SPEED, val);
+		if (error < 0)
+			goto out;
+
+		tsdata->report_speed = val;
+	}
+
+	val_bool = device_property_read_bool(dev, "hycon,noise-filter-enable");
+	error = regmap_write(tsdata->regmap, HY46XX_PWR_NOISE_EN, val_bool);
+	if (error < 0)
+		goto out;
+	tsdata->noise_filter_enable = val_bool;
+
+	error = device_property_read_u32(dev, "hycon,filter-data", &val);
+	if (!error) {
+		error = regmap_write(tsdata->regmap, HY46XX_FILTER_DATA, val);
+		if (error < 0)
+			goto out;
+
+		tsdata->filter_data = val;
+	}
+
+	error = device_property_read_u32(dev, "hycon,gain", &val);
+	if (!error) {
+		error = regmap_write(tsdata->regmap, HY46XX_GAIN, val);
+		if (error < 0)
+			goto out;
+
+		tsdata->gain = val;
+	}
+
+	error = device_property_read_u32(dev, "hycon,edge-offset", &val);
+	if (!error) {
+		error = regmap_write(tsdata->regmap, HY46XX_EDGE_OFFSET, val);
+		if (error < 0)
+			goto out;
+
+		tsdata->edge_offset = val;
+	}
+
+	return;
+out:
+	dev_err(&tsdata->client->dev, "Failed to set default settings");
+}
+
+static void hycon_hy46xx_get_parameters(struct hycon_hy46xx_data *tsdata)
+{
+	int error;
+	u32 val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_THRESHOLD, &val);
+	if (error < 0)
+		goto out;
+	tsdata->threshold = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_GLOVE_EN, &val);
+	if (error < 0)
+		goto out;
+	tsdata->glove_enable = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_REPORT_SPEED, &val);
+	if (error < 0)
+		goto out;
+	tsdata->report_speed = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_PWR_NOISE_EN, &val);
+	if (error < 0)
+		goto out;
+	tsdata->noise_filter_enable = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_FILTER_DATA, &val);
+	if (error < 0)
+		goto out;
+	tsdata->filter_data = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_GAIN, &val);
+	if (error < 0)
+		goto out;
+	tsdata->gain = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_EDGE_OFFSET, &val);
+	if (error < 0)
+		goto out;
+	tsdata->edge_offset = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_RX_NR_USED, &val);
+	if (error < 0)
+		goto out;
+	tsdata->rx_number_used = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_TX_NR_USED, &val);
+	if (error < 0)
+		goto out;
+	tsdata->tx_number_used = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_PWR_MODE, &val);
+	if (error < 0)
+		goto out;
+	tsdata->power_mode = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_FW_VERSION, &val);
+	if (error < 0)
+		goto out;
+	tsdata->fw_version = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_LIB_VERSION, &val);
+	if (error < 0)
+		goto out;
+	tsdata->lib_version = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_TP_INFO, &val);
+	if (error < 0)
+		goto out;
+	tsdata->tp_information = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_TP_CHIP_ID, &val);
+	if (error < 0)
+		goto out;
+	tsdata->tp_chip_id = val;
+
+	error = regmap_read(tsdata->regmap, HY46XX_BOOT_VER, &val);
+	if (error < 0)
+		goto out;
+	tsdata->bootloader_version = val;
+
+	return;
+out:
+	dev_err(&tsdata->client->dev, "Failed to read default settings");
+}
+
+static void hycon_hy46xx_disable_regulator(void *arg)
+{
+	struct hycon_hy46xx_data *data = arg;
+
+	regulator_disable(data->vcc);
+}
+
+static int hycon_hy46xx_probe(struct i2c_client *client,
+					 const struct i2c_device_id *id)
+{
+	struct hycon_hy46xx_data *tsdata;
+	struct input_dev *input;
+	int error;
+
+	dev_dbg(&client->dev, "probing for HYCON HY46XX I2C\n");
+
+	tsdata = devm_kzalloc(&client->dev, sizeof(*tsdata), GFP_KERNEL);
+	if (!tsdata)
+		return -ENOMEM;
+
+	tsdata->vcc = devm_regulator_get(&client->dev, "vcc");
+	if (IS_ERR(tsdata->vcc)) {
+		error = PTR_ERR(tsdata->vcc);
+		if (error != -EPROBE_DEFER)
+			dev_err(&client->dev,
+				"failed to request regulator: %d\n", error);
+		return error;
+	}
+
+	error = regulator_enable(tsdata->vcc);
+	if (error < 0) {
+		dev_err(&client->dev, "failed to enable vcc: %d\n", error);
+		return error;
+	}
+
+	error = devm_add_action_or_reset(&client->dev,
+					 hycon_hy46xx_disable_regulator,
+					 tsdata);
+	if (error)
+		return error;
+
+	tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev,
+						     "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(tsdata->reset_gpio)) {
+		error = PTR_ERR(tsdata->reset_gpio);
+		dev_err(&client->dev,
+			"Failed to request GPIO reset pin, error %d\n", error);
+		return error;
+	}
+
+	if (tsdata->reset_gpio) {
+		usleep_range(5000, 6000);
+		gpiod_set_value_cansleep(tsdata->reset_gpio, 1);
+		usleep_range(5000, 6000);
+		gpiod_set_value_cansleep(tsdata->reset_gpio, 0);
+		msleep(1000);
+	}
+
+	input = devm_input_allocate_device(&client->dev);
+	if (!input) {
+		dev_err(&client->dev, "failed to allocate input device.\n");
+		return -ENOMEM;
+	}
+
+	mutex_init(&tsdata->mutex);
+	tsdata->client = client;
+	tsdata->input = input;
+
+	tsdata->regmap = devm_regmap_init_i2c(client,
+					      &hycon_hy46xx_i2c_regmap_config);
+	if (IS_ERR(tsdata->regmap)) {
+		dev_err(&client->dev, "regmap allocation failed\n");
+		return PTR_ERR(tsdata->regmap);
+	}
+
+	hycon_hy46xx_get_defaults(&client->dev, tsdata);
+	hycon_hy46xx_get_parameters(tsdata);
+
+	input->name = "Hycon Capacitive Touch";
+	input->id.bustype = BUS_I2C;
+	input->dev.parent = &client->dev;
+
+	input_set_abs_params(input, ABS_MT_POSITION_X, 0, -1, 0, 0);
+	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, -1, 0, 0);
+
+	touchscreen_parse_properties(input, true, &tsdata->prop);
+
+	error = input_mt_init_slots(input, HY46XX_MAX_SUPPORTED_POINTS,
+				INPUT_MT_DIRECT);
+	if (error) {
+		dev_err(&client->dev, "Unable to init MT slots.\n");
+		return error;
+	}
+
+	i2c_set_clientdata(client, tsdata);
+
+	error = devm_request_threaded_irq(&client->dev, client->irq,
+					  NULL, hycon_hy46xx_isr, IRQF_ONESHOT,
+					  client->name, tsdata);
+	if (error) {
+		dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
+		return error;
+	}
+
+	error = devm_device_add_group(&client->dev, &hycon_hy46xx_attr_group);
+	if (error)
+		return error;
+
+	error = input_register_device(input);
+	if (error)
+		return error;
+
+	dev_dbg(&client->dev,
+		"HYCON HY46XX initialized: IRQ %d, Reset pin %d.\n",
+		client->irq,
+		tsdata->reset_gpio ? desc_to_gpio(tsdata->reset_gpio) : -1);
+
+	return 0;
+}
+
+static const struct i2c_device_id hycon_hy46xx_id[] = {
+	{ .name = "hy4613" },
+	{ .name = "hy4614" },
+	{ .name = "hy4621" },
+	{ .name = "hy4623" },
+	{ .name = "hy4633" },
+	{ .name = "hy4635" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, hycon_hy46xx_id);
+
+static const struct of_device_id hycon_hy46xx_of_match[] = {
+	{ .compatible = "hycon,hy4613" },
+	{ .compatible = "hycon,hy4614" },
+	{ .compatible = "hycon,hy4621" },
+	{ .compatible = "hycon,hy4623" },
+	{ .compatible = "hycon,hy4633" },
+	{ .compatible = "hycon,hy4635" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, hycon_hy46xx_of_match);
+
+static struct i2c_driver hycon_hy46xx_driver = {
+	.driver = {
+		.name = "hycon_hy46xx",
+		.of_match_table = hycon_hy46xx_of_match,
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+	.id_table = hycon_hy46xx_id,
+	.probe    = hycon_hy46xx_probe,
+};
+
+module_i2c_driver(hycon_hy46xx_driver);
+
+MODULE_AUTHOR("Giulio Benetti <giulio.benetti@benettiengineering.com>");
+MODULE_DESCRIPTION("HYCON HY46XX I2C Touchscreen Driver");
+MODULE_LICENSE("GPL v2");