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
