HID: i2c-hid: elan: Add ili2901 timing

ILI2901 requires reset to pull down time greater than 10ms,
so the configuration post_power_delay_ms is 10, and the chipset
initial time is required to be greater than 100ms,
so the post_gpio_reset_on_delay_ms is set to 100.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Zhengqiao Xia <xiazhengqiao@huaqin.corp-partner.google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

HID: i2c-hid: elan: Add ili9882t timing

The ili9882t is a TDDI IC (Touch with Display Driver). The
datasheet specifies there should be 60ms between touch SDA
sleep and panel RESX. Doug's series[1] allows panels and
touchscreens to power on/off together, so we can add the 65 ms
delay in i2c_hid_core_suspend before panel_unprepare.

Because ili9882t touchscrgeen is a panel follower, and
needs to use vccio-supply instead of vcc33-supply, so set
it NULL to ili9882t_chip_data, then not use vcc33 regulator.

[1]: https://lore.kernel.org/all/20230727171750.633410-1-dianders@chromium.org

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Cong Yang <yangcong5@huaqin.corp-partner.google.com>
Acked-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/20230802071947.1683318-3-yangcong5@huaqin.corp-partner.google.com
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>

HID: i2c-hid: Switch i2c drivers back to use .probe()

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then
03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert
back to (the new) .probe() to be able to eventually drop .probe_new() from
struct i2c_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

HID: i2c: use simple i2c probe

All these drivers have an i2c probe function which doesn't use the
"struct i2c_device_id *id" parameter, so they can trivially be
converted to the "probe_new" style of probe with a single argument.

This is part of an ongoing transition to single-argument i2c probe
functions. Old-style probe functions involve a call to i2c_match_id:
in drivers/i2c/i2c-core-base.c,

/*
* When there are no more users of probe(),
* rename probe_new to probe.
*/
if (driver->probe_new)
status = driver->probe_new(client);
else if (driver->probe)
status = driver->probe(client,
i2c_match_id(driver->id_table, client));
else
status = -EINVAL;

Drivers which don't need the second parameter can be declared using
probe_new instead, avoiding the call to i2c_match_id. Drivers which do
can still be converted to probe_new-style, calling i2c_match_id
themselves (as is done currently for of_match_id).

This change was done using the following Coccinelle script, and fixed
up for whitespace changes:

@ rule1 @
identifier fn;
identifier client, id;
@@

- static int fn(struct i2c_client *client, const struct i2c_device_id *id)
+ static int fn(struct i2c_client *client)
{
...when != id
}

@ rule2 depends on rule1 @
identifier rule1.fn;
identifier driver;
@@

struct i2c_driver driver = {
- .probe
+ .probe_new
=
(
fn
|
- &fn
+ fn
)
,
};

Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

HID: i2c-hid: elan: Add support for Elan eKTH6915 i2c-hid touchscreens

Like many i2c-hid touchscreen controllers, the Elan eKTH6915 has a
reset GPIO hooked up to it. According to the datasheet, the way we're
supposed to turn the touchscreen on is:

1. Turn on the 3.3V supply.
2. Turn on the IO supply. It's OK if this is hardwired to the 3.3V
supply, but if it's not then it must be turned on _after_ the 3.3V
supply.
3. Wait >= 1 ms.
4. Deassert the reset GPIO (reset GPIO is active low, so there would
be a leakage path if this was deasserted _before_ the IO supply).
5. Wait 300 ms.

Much of the above can be handled by the generic i2c-hid-of driver, but
the "reset" GPIO is not supported by that driver. Thus we'll do the
same as we did for Goodix and add a new tiny driver that uses the
i2c-hid core.

NOTE: support for this new touchscreen could theorically fit into the
Goodix driver. I've made it a separate driver because the Elan driver
supports _two_ regulators and it's unclear exactly how that would fit
in with commit 18eeef46d359 ("HID: i2c-hid: goodix: Tie the reset line
to true state of the regulator").

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>