HI Dmitry: ... module_i2c_driver(elan_driver); static int __init elan_init(void) { return elan_create_lid_handler(); } static void __exit elan_exit(void) { if (elan_mode_wq) elan_destroy_lid_handler(); } module_init(elan_init); module_exit(elan_exit); ... If I change to elan_create_lid_handler() at module_init, complie error as follow. <pre><b>./include/linux/module.h:130:49:</b> <font color="#C01C28"><b>error: </b></font>redefinition of '<b>__inittest</b>' 130 | static inline initcall_t __maybe_unused <font color="#C01C28"><b>__inittest</b></font>(void) \ | <font color="#C01C28"><b>^~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1666:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_init</b>' 1666 | <font color="#2AA1B3"><b>module_init</b></font>(elan_init); | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/module.h:130:49:</b> <font color="#2AA1B3"><b>note: </b></font>previous definition of '<b>__inittest</b>' with type '<b>int (*(void))(void)</b>' 130 | static inline initcall_t __maybe_unused <font color="#2AA1B3"><b>__inittest</b></font>(void) \ | <font color="#2AA1B3"><b>^~~~~~~~~~</b></font> <b>./include/linux/device/driver.h:266:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_init</b>' 266 | <font color="#2AA1B3"><b>module_init</b></font>(__driver##_init); \ | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/i2c.h:956:9:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_driver</b>' 956 | <font color="#2AA1B3"><b>module_driver</b></font>(__i2c_driver, i2c_add_driver, \ | <font color="#2AA1B3"><b>^~~~~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1653:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_i2c_driver</b>' 1653 | <font color="#2AA1B3"><b>module_i2c_driver</b></font>(elan_driver); | <font color="#2AA1B3"><b>^~~~~~~~~~~~~~~~~</b></font> <b>./include/linux/module.h:132:13:</b> <font color="#C01C28"><b>error: </b></font>redefinition of '<b>init_module</b>' 132 | int <font color="#C01C28"><b>init_module</b></font>(void) __copy(initfn) \ | <font color="#C01C28"><b>^~~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1666:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_init</b>' 1666 | <font color="#2AA1B3"><b>module_init</b></font>(elan_init); | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/module.h:132:13:</b> <font color="#2AA1B3"><b>note: </b></font>previous definition of '<b>init_module</b>' with type '<b>int(void)</b>' 132 | int <font color="#2AA1B3"><b>init_module</b></font>(void) __copy(initfn) \ | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/device/driver.h:266:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_init</b>' 266 | <font color="#2AA1B3"><b>module_init</b></font>(__driver##_init); \ | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/i2c.h:956:9:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_driver</b>' 956 | <font color="#2AA1B3"><b>module_driver</b></font>(__i2c_driver, i2c_add_driver, \ | <font color="#2AA1B3"><b>^~~~~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1653:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_i2c_driver</b>' 1653 | <font color="#2AA1B3"><b>module_i2c_driver</b></font>(elan_driver); | <font color="#2AA1B3"><b>^~~~~~~~~~~~~~~~~</b></font> <b>./include/linux/module.h:138:49:</b> <font color="#C01C28"><b>error: </b></font>redefinition of '<b>__exittest</b>' 138 | static inline exitcall_t __maybe_unused <font color="#C01C28"><b>__exittest</b></font>(void) \ | <font color="#C01C28"><b>^~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1667:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_exit</b>' 1667 | <font color="#2AA1B3"><b>module_exit</b></font>(elan_exit); | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/module.h:138:49:</b> <font color="#2AA1B3"><b>note: </b></font>previous definition of '<b>__exittest</b>' with type '<b>void (*(void))(void)</b>' 138 | static inline exitcall_t __maybe_unused <font color="#2AA1B3"><b>__exittest</b></font>(void) \ | <font color="#2AA1B3"><b>^~~~~~~~~~</b></font> <b>./include/linux/device/driver.h:271:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_exit</b>' 271 | <font color="#2AA1B3"><b>module_exit</b></font>(__driver##_exit); | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/i2c.h:956:9:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_driver</b>' 956 | <font color="#2AA1B3"><b>module_driver</b></font>(__i2c_driver, i2c_add_driver, \ | <font color="#2AA1B3"><b>^~~~~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1653:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_i2c_driver</b>' 1653 | <font color="#2AA1B3"><b>module_i2c_driver</b></font>(elan_driver); | <font color="#2AA1B3"><b>^~~~~~~~~~~~~~~~~</b></font> <b>./include/linux/module.h:140:14:</b> <font color="#C01C28"><b>error: </b></font>redefinition of '<b>cleanup_module</b>' 140 | void <font color="#C01C28"><b>cleanup_module</b></font>(void) __copy(exitfn) \ | <font color="#C01C28"><b>^~~~~~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1667:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_exit</b>' 1667 | <font color="#2AA1B3"><b>module_exit</b></font>(elan_exit); | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/module.h:140:14:</b> <font color="#2AA1B3"><b>note: </b></font>previous definition of '<b>cleanup_module</b>' with type '<b>void(void)</b>' 140 | void <font color="#2AA1B3"><b>cleanup_module</b></font>(void) __copy(exitfn) \ | <font color="#2AA1B3"><b>^~~~~~~~~~~~~~</b></font> <b>./include/linux/device/driver.h:271:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_exit</b>' 271 | <font color="#2AA1B3"><b>module_exit</b></font>(__driver##_exit); | <font color="#2AA1B3"><b>^~~~~~~~~~~</b></font> <b>./include/linux/i2c.h:956:9:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_driver</b>' 956 | <font color="#2AA1B3"><b>module_driver</b></font>(__i2c_driver, i2c_add_driver, \ | <font color="#2AA1B3"><b>^~~~~~~~~~~~~</b></font> <b>drivers/input/mouse/elan_i2c_core.c:1653:1:</b> <font color="#2AA1B3"><b>note: </b></font>in expansion of macro '<b>module_i2c_driver</b>' 1653 | <font color="#2AA1B3"><b>module_i2c_driver</b></font>(elan_driver); | <font color="#2AA1B3"><b>^~~~~~~~~~~~~~~~~</b></font> </pre> THANJS JINGLE -----Original Message----- From: Jingle.Wu [mailto:jingle.wu@xxxxxxxxxx] Sent: Wednesday, July 5, 2023 2:09 PM To: 'Dmitry Torokhov' <dmitry.torokhov@xxxxxxxxx> Cc: 'linux-kernel@xxxxxxxxxxxxxxx' <linux-kernel@xxxxxxxxxxxxxxx>; 'linux-input@xxxxxxxxxxxxxxx' <linux-input@xxxxxxxxxxxxxxx>; 'phoenix@xxxxxxxxxx' <phoenix@xxxxxxxxxx>; 'josh.chen@xxxxxxxxxx' <josh.chen@xxxxxxxxxx>; 'dave.wang@xxxxxxxxxx' <dave.wang@xxxxxxxxxx> Subject: RE: [PATCH] Input: elan_i2c - Implement inhibit/uninhibit functions. HI Dmitry: 1. > +static void elan_input_lid_event(struct input_handle *handle, > +unsigned int type, > + unsigned int code, int value) { > + struct elan_tp_data *data, *n; > + > + if (type == EV_SW && code == SW_LID) { > + list_for_each_entry_safe(data, n, &elan_devices_with_lid_handler, > +list) { Why do you need the "_safe()" variant here? -> Because I took the above link as reference. https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/3 578852/7/drivers/hid/hid-multitouch.c#394 2. > + data->lid_switch = true; > + INIT_LIST_HEAD(&data->list); > + INIT_WORK(&data->lid_work, lid_work_handler); > + list_add_tail(&data->list, &elan_devices_with_lid_handler); It looks like you call elan_create_lid_handler() from elan_probe() which means it can be called several times (we should not assume there is only one controller), I do not see it being destroyed in remove() either, so it will break if you bind/unbind the driver. I also not sure why you need the list of you have a handler per device. -> If the elan_create_lid_handler() function not be put into probe(), -> the lid handler would be invalid in elan private data("struct elan_tp_data *data"). Or do you have any suggestions for it? Thanks. 3. > + error = elan_create_lid_handler(data); > + if (error) > + dev_err(dev, "failed to create lid handler: %d\n", error); Do we need this on _ALL_ devices with ELan controllers, or just certain ones? If we need this on all devices how did it work before? -> Yes, we need this on all device. In Chromeos kernel v5.4 before, the elan_inhibit()/uninhibit function was built and worked successfully in elan_i2c_driver. https://chromium.googlesource.com/chromiumos/third_party/kernel/+/refs/heads /chromeos-5.4/drivers/input/mouse/elan_i2c_core.c#353 Thanks JINGLE -----Original Message----- From: Dmitry Torokhov [mailto:dmitry.torokhov@xxxxxxxxx] Sent: Friday, June 30, 2023 6:57 AM To: jingle.wu <jingle.wu@xxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-input@xxxxxxxxxxxxxxx; phoenix@xxxxxxxxxx; josh.chen@xxxxxxxxxx; dave.wang@xxxxxxxxxx Subject: Re: [PATCH] Input: elan_i2c - Implement inhibit/uninhibit functions. Hi Jingle, On Wed, May 31, 2023 at 05:03:40PM +0800, jingle.wu wrote: > Add inhibit/uninhibit functions. You need to provide justification for this change, i.e. explain why you need this/what is currently not working or working sub-optimally. > > Signed-off-by: Jingle.wu <jingle.wu@xxxxxxxxxx> > --- > drivers/input/mouse/elan_i2c_core.c | 207 > ++++++++++++++++++++++++++++ > 1 file changed, 207 insertions(+) > > diff --git a/drivers/input/mouse/elan_i2c_core.c > b/drivers/input/mouse/elan_i2c_core.c > index 5f0d75a45c80..4ea57f4c7bd4 100644 > --- a/drivers/input/mouse/elan_i2c_core.c > +++ b/drivers/input/mouse/elan_i2c_core.c > @@ -56,6 +56,7 @@ struct elan_tp_data { > struct input_dev *input; > struct input_dev *tp_input; /* trackpoint input node */ > struct regulator *vcc; > + struct list_head list; /* for list of devices needing input handler */ > > const struct elan_transport_ops *ops; > > @@ -63,6 +64,11 @@ struct elan_tp_data { > struct completion fw_completion; > bool in_fw_update; > > + struct work_struct lid_work; > + bool lid_switch; > + int lid_value; > + bool in_inhibit; > + > struct mutex sysfs_mutex; > > unsigned int max_x; > @@ -96,6 +102,9 @@ struct elan_tp_data { > u32 quirks; /* Various quirks */ > }; > > +static struct workqueue_struct *elan_mode_wq; static > +LIST_HEAD(elan_devices_with_lid_handler); > + > static u32 elan_i2c_lookup_quirks(u16 ic_type, u16 product_id) { > static const struct { > @@ -329,6 +338,74 @@ static int elan_initialize(struct elan_tp_data *data, bool skip_reset) > return error; > } > > +static int elan_reactivate(struct elan_tp_data *data) { > + struct device *dev = &data->client->dev; > + int error; > + > + error = elan_set_power(data, true); > + if (error) > + dev_err(dev, "failed to restore power: %d\n", error); > + > + error = data->ops->sleep_control(data->client, false); > + if (error) { > + dev_err(dev, > + "failed to wake device up: %d\n", error); > + return error; > + } > + > + return error; > +} > + > +static int elan_inhibit(struct input_dev *input_dev) I would rather you did not call it inhibit/uninhibit because this is not what it does. Please split the logic for recalibration from logic of powering on and off the device. I also hope in the future firmware revisions the distinction will be more clear (i.e. have a separate method/command to recalibrate baseline on demand). > +{ > + struct elan_tp_data *data = input_get_drvdata(input_dev); > + struct i2c_client *client = data->client; > + int error; > + > + dev_dbg(&client->dev, "inhibiting\n"); > + /* > + * We are taking the mutex to make sure sysfs operations are > + * complete before we attempt to bring the device into low[er] > + * power mode. > + */ > + error = mutex_lock_interruptible(&data->sysfs_mutex); > + if (error) > + return error; > + > + disable_irq(client->irq); > + > + error = elan_set_power(data, false); > + if (error) > + enable_irq(client->irq); > + > + data->in_inhibit = true; > + mutex_unlock(&data->sysfs_mutex); > + > + return error; > +} > + > +static int elan_uninhibit(struct input_dev *input_dev) { > + struct elan_tp_data *data = input_get_drvdata(input_dev); > + struct i2c_client *client = data->client; > + int error; > + > + dev_dbg(&client->dev, "uninhibiting\n"); > + error = mutex_lock_interruptible(&data->sysfs_mutex); > + if (error) > + return error; > + > + error = elan_reactivate(data); > + if (error == 0) > + enable_irq(client->irq); > + > + data->in_inhibit = false; > + mutex_unlock(&data->sysfs_mutex); > + > + return error; > +} > + > static int elan_query_device_info(struct elan_tp_data *data) { > int error; > @@ -1187,6 +1264,124 @@ static void elan_disable_regulator(void *_data) > regulator_disable(data->vcc); > } > > +static void lid_work_handler(struct work_struct *work) { > + struct elan_tp_data *data = container_of(work, struct elan_tp_data, > + lid_work); > + > + if (data->lid_value) > + elan_inhibit(data->input); > + else > + elan_uninhibit(data->input); > + > +} > + > +static void elan_input_lid_event(struct input_handle *handle, unsigned int type, > + unsigned int code, int value) { > + struct elan_tp_data *data, *n; > + > + if (type == EV_SW && code == SW_LID) { > + list_for_each_entry_safe(data, n, &elan_devices_with_lid_handler, > +list) { Why do you need the "_safe()" variant here? > + data->lid_value = value; > + queue_work(elan_mode_wq, &data->lid_work); > + } > + } > + > +} > + > +struct elan_input_lid { > + struct input_handle handle; > +}; > + > +static int elan_input_lid_connect(struct input_handler *handler, > + struct input_dev *dev, > + const struct input_device_id *id) { > + struct elan_input_lid *lid; > + char *name; > + int error; > + > + lid = kzalloc(sizeof(*lid), GFP_KERNEL); > + if (!lid) > + return -ENOMEM; > + name = kasprintf(GFP_KERNEL, "elan-i2c-lid-%s", dev_name(&dev->dev)); > + if (!name) { > + error = -ENOMEM; > + goto err_free_lid; > + } > + lid->handle.dev = dev; > + lid->handle.handler = handler; > + lid->handle.name = name; > + lid->handle.private = lid; > + error = input_register_handle(&lid->handle); > + if (error) > + goto err_free_name; > + error = input_open_device(&lid->handle); > + if (error) > + goto err_unregister_handle; > + return 0; > +err_unregister_handle: > + input_unregister_handle(&lid->handle); > +err_free_name: > + kfree(name); > +err_free_lid: > + kfree(lid); > + return error; > +} > + > +static void elan_input_lid_disconnect(struct input_handle *handle) { > + struct elan_input_lid *lid = handle->private; > + > + input_close_device(handle); > + input_unregister_handle(handle); > + kfree(handle->name); > + kfree(lid); > +} > + > +static const struct input_device_id elan_input_lid_ids[] = { > + { > + .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_SWBIT, > + .evbit = { BIT_MASK(EV_SW) }, > + .swbit = { [BIT_WORD(SW_LID)] = BIT_MASK(SW_LID) }, > + }, > + { }, > +}; > + > +static struct input_handler elan_input_lid_handler = { > + .event = elan_input_lid_event, > + .connect = elan_input_lid_connect, > + .disconnect = elan_input_lid_disconnect, > + .name = "elan-i2c-lid", > + .id_table = elan_input_lid_ids, > +}; > + > +static int elan_create_lid_handler(struct elan_tp_data *data) { > + int error = 0; > + > + elan_mode_wq = create_singlethread_workqueue("elan-i2c-lid"); > + if (elan_mode_wq == NULL) > + return -ENOMEM; > + error = input_register_handler(&elan_input_lid_handler); > + if (error) > + goto remove_wq; > + > + data->lid_switch = true; > + INIT_LIST_HEAD(&data->list); > + INIT_WORK(&data->lid_work, lid_work_handler); > + list_add_tail(&data->list, &elan_devices_with_lid_handler); It looks like you call elan_create_lid_handler() from elan_probe() which means it can be called several times (we should not assume there is only one controller), I do not see it being destroyed in remove() either, so it will break if you bind/unbind the driver. I also not sure why you need the list of you have a handler per device. > + > + return 0; > + > +remove_wq: > + data->lid_switch = false; > + destroy_workqueue(elan_mode_wq); > + elan_mode_wq = NULL; > + return error; > +} > + > static int elan_probe(struct i2c_client *client) { > const struct elan_transport_ops *transport_ops; @@ -1325,6 +1520,10 > @@ static int elan_probe(struct i2c_client *client) > } > } > > + error = elan_create_lid_handler(data); > + if (error) > + dev_err(dev, "failed to create lid handler: %d\n", error); Do we need this on _ALL_ devices with ELan controllers, or just certain ones? If we need this on all devices how did it work before? > + > return 0; > } > > @@ -1334,6 +1533,10 @@ static int elan_suspend(struct device *dev) > struct elan_tp_data *data = i2c_get_clientdata(client); > int ret; > > + /* Wait for switch on completion */ > + if (data->lid_switch) > + flush_workqueue(elan_mode_wq); > + > /* > * We are taking the mutex to make sure sysfs operations are > * complete before we attempt to bring the device into low[er] @@ > -1371,6 +1574,10 @@ static int elan_resume(struct device *dev) > struct elan_tp_data *data = i2c_get_clientdata(client); > int error; > > + /* Wait for switch on completion */ > + if (data->lid_switch) > + flush_workqueue(elan_mode_wq); > + > if (!device_may_wakeup(dev)) { > error = regulator_enable(data->vcc); > if (error) { > -- > 2.34.1 > Thanks. -- Dmitry