Dear Dmitry,
On Tue, Sep 26, 2017 at 11:08:45PM -0700, Dmitry Torokhov wrote:
> Hi Ahmet,
>
> On Mon, Sep 25, 2017 at 04:39:20PM +0200, Ahmet Inan wrote:
> > The 3000 series have a new protocol which allows to report up to 5 points
> > in a single 66 byte frame. One must always read in 66 byte frames.
> > To support up to 10 points, two consecutive frames need to be read:
> > The first frame says how many points until sync.
> > The second frame must say zero points or both frames must be discarded.
> >
> > To be able to work with the higher 400KHz I2C bus rate, one must
> > successfully send a special package prior _each_ read or the controller
> > will refuse to cooperate.
> >
> > This is a minimal implementation based on egalax_i2c.c (which can be found
> > on the internet) and egalax_ts.c but without the vendor interface and no
> > power management support.
> >
> > Signed-off-by: Ahmet Inan <inan@xxxxxxxxx>
> > ---
> > .../bindings/input/touchscreen/exc3000.txt | 29 ++++
> > drivers/input/touchscreen/Kconfig | 10 ++
> > drivers/input/touchscreen/Makefile | 1 +
> > drivers/input/touchscreen/exc3000.c | 153 +++++++++++++++++++++
> > 4 files changed, 193 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/input/touchscreen/exc3000.txt
> > create mode 100644 drivers/input/touchscreen/exc3000.c
> >
> > diff --git a/Documentation/devicetree/bindings/input/touchscreen/exc3000.txt b/Documentation/devicetree/bindings/input/touchscreen/exc3000.txt
> > new file mode 100644
> > index 000000000000..3c824a084581
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/input/touchscreen/exc3000.txt
> > @@ -0,0 +1,29 @@
> > +* EETI EXC3000 Multiple Touch Controller
> > +
> > +Required properties:
> > +- compatible: must be "eeti,exc3000"
> > +- reg: i2c slave address
> > +- interrupt-parent: the phandle for the interrupt controller
> > +- interrupts: touch controller interrupt
> > +- irq-gpios: the gpio pin to be used as irq pin
>
> I do not believe this property is needed as you do not use gpiod API in
> the driver.
While playing with the controller it was convenient to easily access the
gpio that way for wakeup purposes .. removed.
> Please also copy device tree mailing list and Rob Herring for feedback
> on the binding.
done.
> > +- touchscreen-size-x: See touchscreen.txt
> > +- touchscreen-size-y: See touchscreen.txt
> > +
> > +Optional properties:
> > +- touchscreen-inverted-x: See touchscreen.txt
> > +- touchscreen-inverted-y: See touchscreen.txt
> > +- touchscreen-swapped-x-y: See touchscreen.txt
> > +
> > +Example:
> > +
> > + exc3000@2a {
> > + compatible = "eeti,exc3000";
> > + reg = <0x2a>;
> > + interrupt-parent = <&gpio1>;
> > + interrupts = <9 8>; // active low level-sensitive
> > + irq-gpios = <&gpio1 9 0>;
> > + touchscreen-size-x = <4096>;
> > + touchscreen-size-y = <4096>;
> > + touchscreen-inverted-x;
> > + touchscreen-swapped-x-y;
> > + };
> > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
> > index 0bf78ff1ae88..9ea2d9287b38 100644
> > --- a/drivers/input/touchscreen/Kconfig
> > +++ b/drivers/input/touchscreen/Kconfig
> > @@ -314,6 +314,16 @@ config TOUCHSCREEN_EGALAX_SERIAL
> > To compile this driver as a module, choose M here: the
> > module will be called egalax_ts_serial.
> >
> > +config TOUCHSCREEN_EXC3000
> > + tristate "EETI EXC3000 multi-touch panel support"
> > + depends on I2C
> > + help
> > + Say Y here to enable support for I2C connected EETI
> > + EXC3000 multi-touch panels.
> > +
> > + To compile this driver as a module, choose M here: the
> > + module will be called exc3000.
> > +
> > config TOUCHSCREEN_FUJITSU
> > tristate "Fujitsu serial touchscreen"
> > select SERIO
> > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
> > index f720bc30ada9..48118379fee7 100644
> > --- a/drivers/input/touchscreen/Makefile
> > +++ b/drivers/input/touchscreen/Makefile
> > @@ -38,6 +38,7 @@ obj-$(CONFIG_TOUCHSCREEN_ELAN) += elants_i2c.o
> > obj-$(CONFIG_TOUCHSCREEN_ELO) += elo.o
> > obj-$(CONFIG_TOUCHSCREEN_EGALAX) += egalax_ts.o
> > obj-$(CONFIG_TOUCHSCREEN_EGALAX_SERIAL) += egalax_ts_serial.o
> > +obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o
> > obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o
> > obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix.o
> > obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o
> > diff --git a/drivers/input/touchscreen/exc3000.c b/drivers/input/touchscreen/exc3000.c
> > new file mode 100644
> > index 000000000000..022b3c6f227d
> > --- /dev/null
> > +++ b/drivers/input/touchscreen/exc3000.c
> > @@ -0,0 +1,153 @@
> > +/*
> > + * Driver for I2C connected EETI EXC3000 multiple touch controller
> > + *
> > + * Copyright (C) 2017 Ahmet Inan <inan@xxxxxxxxx>
> > + *
> > + * minimal implementation based on egalax_ts.c and egalax_i2c.c
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/i2c.h>
> > +#include <linux/input.h>
> > +#include <linux/irq.h>
> > +#include <linux/input/mt.h>
> > +#include <linux/input/touchscreen.h>
> > +#include <asm/unaligned.h>
> > +
> > +#define EXC3000_NUM_SLOTS 10
> > +#define EXC3000_SLOTS_PER_FRAME 5
> > +#define EXC3000_LEN_FRAME 66
> > +#define EXC3000_LEN_POINT 10
> > +#define EXC3000_MT_EVENT 6
> > +
> > +struct exc3000_data {
> > + struct i2c_client *client;
> > + struct input_dev *input;
> > + struct touchscreen_properties prop;
> > + u8 buf[2 * EXC3000_LEN_FRAME];
> > +};
> > +
> > +static void exc3000_process(struct input_dev *input,
> > + struct touchscreen_properties *prop, u8 *buf, int num)
> > +{
> > + for (; num--; buf += EXC3000_LEN_POINT) {
> > + if (buf[0] & 1) {
> > + input_mt_slot(input, buf[1]);
> > + input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
> > + touchscreen_report_pos(input, prop,
> > + get_unaligned_le16(buf + 2),
> > + get_unaligned_le16(buf + 4), true);
> > + }
> > + }
> > +}
> > +
> > +static int exc3000_read(struct i2c_client *client, u8 *buf)
> > +{
> > + return i2c_master_send(client, "'", 2) != 2 ||
> > + i2c_master_recv(client, buf,
> > + EXC3000_LEN_FRAME) != EXC3000_LEN_FRAME ||
>
> Please align this line with the opening paren of i2c_master_recv().
done.
> Can this be a single read/write transaction with 2 messages via
> i2c_tranfer()?
I tried, but this does not work:
return i2c_transfer(adapter, msgs, 2) != 2 ||
where this does work:
return i2c_transfer(adapter, msgs, 1) != 1 ||
i2c_transfer(adapter, msgs + 1, 1) != 1 ||
so its not really worth the preliminary work needed to do it the
i2c_transfer() way.
>
> > + get_unaligned_le16(buf) != EXC3000_LEN_FRAME ||
> > + buf[2] != EXC3000_MT_EVENT;
> > +}
> > +
> > +static irqreturn_t exc3000_interrupt(int irq, void *dev_id)
> > +{
> > + struct exc3000_data *data = dev_id;
> > + struct i2c_client *client = data->client;
> > + struct input_dev *input = data->input;
> > + struct touchscreen_properties *prop = &data->prop;
> > + u8 *buf = data->buf;
> > +
> > + if (exc3000_read(client, buf) || !buf[3] || buf[3] > EXC3000_NUM_SLOTS)
> > + return IRQ_HANDLED;
> > + if (buf[3] <= EXC3000_SLOTS_PER_FRAME) {
> > + exc3000_process(input, prop, buf + 4, buf[3]);
> > + } else {
> > + if (exc3000_read(client, buf + EXC3000_LEN_FRAME) ||
> > + buf[EXC3000_LEN_FRAME + 3])
> > + return IRQ_HANDLED;
> > + exc3000_process(input, prop, buf + 4, EXC3000_SLOTS_PER_FRAME);
> > + exc3000_process(input, prop, buf + EXC3000_LEN_FRAME + 4,
> > + buf[3] - EXC3000_SLOTS_PER_FRAME);
> > + }
> > + input_mt_sync_frame(input);
> > + input_sync(input);
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static int exc3000_probe(struct i2c_client *client,
> > + const struct i2c_device_id *id)
> > +{
> > + struct exc3000_data *data;
> > + struct input_dev *input;
> > + int error;
> > +
> > + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
> > + if (!data)
> > + return -ENOMEM;
> > +
> > + input = devm_input_allocate_device(&client->dev);
> > + if (!input)
> > + return -ENOMEM;
> > +
> > + input->name = "EETI EXC3000 Touch Screen";
> > + input->id.bustype = BUS_I2C;
> > +
> > + input_set_abs_params(input, ABS_MT_POSITION_X, 0, 4095, 0, 0);
> > + input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
> > + touchscreen_parse_properties(input, true, &data->prop);
> > +
> > + error = input_mt_init_slots(input, EXC3000_NUM_SLOTS,
> > + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
> > + if (error)
> > + return error;
> > +
> > + error = input_register_device(input);
> > + if (error)
> > + return error;
> > +
> > + data->input = input;
> > + data->client = client;
> > + i2c_set_clientdata(client, data);
> > +
> > + error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
> > + exc3000_interrupt, IRQF_ONESHOT, client->name, data);
> > + if (error)
> > + return error;
> > +
> > + return 0;
> > +}
> > +
> > +static const struct i2c_device_id exc3000_id[] = {
> > + { "exc3000", 0 },
> > + { }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(i2c, exc3000_id);
> > +
> > +#ifdef CONFIG_OF
> > +static const struct of_device_id exc3000_of_match[] = {
> > + { .compatible = "eeti,exc3000" },
> > + { }
> > +};
> > +#endif
> > +
> > +static struct i2c_driver exc3000_driver = {
> > + .driver = {
> > + .name = "exc3000",
> > + .of_match_table = of_match_ptr(exc3000_of_match),
> > + },
> > + .id_table = exc3000_id,
> > + .probe = exc3000_probe,
> > +};
> > +
> > +module_i2c_driver(exc3000_driver);
> > +
> > +MODULE_AUTHOR("Ahmet Inan <inan@xxxxxxxxx>");
> > +MODULE_DESCRIPTION("I2C connected EETI EXC3000 multiple touch controller driver");
> > +MODULE_LICENSE("GPL");
> > --
> > 2.11.0
> >
>
> Thanks.
>
> --
> Dmitry
Best Regards,
Ahmet
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