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2022-10-18HID: i2c: use simple i2c probeStephen Kitt1-3/+2
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>
2022-06-08HID: i2c-hid: elan: Add support for Elan eKTH6915 i2c-hid touchscreensDouglas Anderson1-0/+130
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>