Hi, On 9/13/21 2:59 PM, Pali Rohár wrote: > On Monday 13 September 2021 14:48:46 Hans de Goede wrote: >> Hi, >> >> On 9/13/21 2:44 PM, Pali Rohár wrote: >>> On Monday 13 September 2021 14:40:28 Hans de Goede wrote: >>>> Hi, >>>> >>>> Overall this patch looks good, I have 2 remarks: >>>> >>>> 1. Your commit message needs some work, the first line (Subject) should >>>> briefly describe the change with a subsystem prefix, so something like this: >>>> >>>> platform/x86: dell-wmi: Add SW_TABLET_MODE support for Dell Inspiron 2in1 >>>> >>>> And then an empty line followed by a "body" with a bit more detailed description. >>>> >>>> And last but not least you need to add a Signed-off-by line like this: >>>> >>>> Singed-off-by: Troy Rollo <linux2021@xxxxxxxxxxxxxxx> >>>> >>>> Which indicates that you authored the patch and are submitting it under >>>> the standard kernel license, see: >>>> https://elinux.org/Developer_Certificate_Of_Origin >>>> >>>> 2. Also have 1 remark about the code, see below. >>>> >>>> >>>> On 9/9/21 5:35 AM, Troy Rollo wrote: >>>>> --- >>>>> drivers/platform/x86/dell/dell-wmi-base.c | 36 ++++++++++++++++------- >>>>> 1 file changed, 26 insertions(+), 10 deletions(-) >>>>> >>>>> diff --git a/drivers/platform/x86/dell/dell-wmi-base.c b/drivers/platform/x86/dell/dell-wmi-base.c >>>>> index 089c125e18f7..474ca05055ab 100644 >>>>> --- a/drivers/platform/x86/dell/dell-wmi-base.c >>>>> +++ b/drivers/platform/x86/dell/dell-wmi-base.c >>>>> @@ -309,6 +309,9 @@ static const struct key_entry dell_wmi_keymap_type_0010[] = { >>>>> * Keymap for WMI events of type 0x0011 >>>>> */ >>>>> static const struct key_entry dell_wmi_keymap_type_0011[] = { >>>>> + /* Reflex keyboard switch on 2n1 devices */ >>>>> + { KE_VSW, 0xe070, { .sw = { SW_TABLET_MODE } } }, >>>>> + >>>> >>>> By adding this here, any device loading the dell-wmi driver will now advertise >>>> that it supports SW_TABLET_MODE reporting, even when it does not. This will >>>> cause e.g. GNOME40 to disable accelerometer based rotation since when >>>> SW_TABLET_MODE=0 is being reported then GNOME40 assumes it is running on a >>>> 2in1 in laptop mode and thus disable auto-rotation (and also the on-screen-kbd). >>>> >>>> So advertising a non functional (always reporting 0) SW_TABLET_MODE switch >>>> is harmful and this change will do this. >>> >>> Good catch. This code needs some rework as based on above gnome >>> behavior, this change breaks support for all existing older Dell >>> laptops. >>> >>> It it problem only with SW_TABLET_MODE? Or with any KE_VSW? >> >> It is a problem for any KE_SW / KE_VSW since unlike keys/buttons which >> are always unpressed by default and don't cause userspace to do anything >> until a press is reported, switches have a meaning in both their >> 0 and 1 state, so merely reporting the presence of a switch can cause >> userspace to change behavior. >> >> Note I'm not aware of any SW other then SW_TABLET_MODE actually causing >> issues, but in theory this is an issue with any SW because of the reason >> which I just gave. > > Well, this argument makes sense for any switch. > > But all other defined keys in this driver are "standard" keys which may > or may not be present on de-facto standard keyboard: capslock, > brightness keys, volume keys, wifi key, eject key, ... > Probably generic AT keyboard driver may also report more standard keys > than it has. > > So I'm not sure if it makes sense to rewrite wmi driver to dynamically > allocate presence of also every key based on first press. > > If some userspace software depends on capabilities of "standard" keys > and reacts differently then I guess it is broken... > > But for switches this dynamic behavior as you described is needed. Right, I fully agree. Regards, Hans >>>> Since you already have special handling for the tablet-mode WMI events, >>>> it would be better to use a separate input-device which just reports >>>> SW_TABLET_MODE and which gets dynamically created upon receiving the >>>> first 0x0011 0xe070 event. See the >>>> drivers/platform/x86/intel/vbtn.c >>>> drivers/platform/x86/intel/hid.c >>>> >>>> Drivers for an example of 2 drivers already doing this. >>>> >>>> Regards, >>>> >>>> Hans >>>> >>>> >>>> >>>>> /* Battery unplugged */ >>>>> { KE_IGNORE, 0xfff0, { KEY_RESERVED } }, >>>>> >>>>> @@ -344,17 +347,19 @@ static const struct key_entry dell_wmi_keymap_type_0012[] = { >>>>> { KE_IGNORE, 0xe035, { KEY_RESERVED } }, >>>>> }; >>>>> >>>>> -static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code) >>>>> +static int dell_wmi_process_key(struct wmi_device *wdev, int type, int code, u16 *buffer, int remaining) >>>>> { >>>>> struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev); >>>>> const struct key_entry *key; >>>>> + int used = 0; >>>>> + int value = 1; >>>>> >>>>> key = sparse_keymap_entry_from_scancode(priv->input_dev, >>>>> (type << 16) | code); >>>>> if (!key) { >>>>> pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n", >>>>> type, code); >>>>> - return; >>>>> + return 0; >>>>> } >>>>> >>>>> pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code); >>>>> @@ -363,16 +368,22 @@ static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code) >>>>> if ((key->keycode == KEY_BRIGHTNESSUP || >>>>> key->keycode == KEY_BRIGHTNESSDOWN) && >>>>> acpi_video_handles_brightness_key_presses()) >>>>> - return; >>>>> + return 0; >>>>> >>>>> if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request) >>>>> - return; >>>>> + return 0; >>>>> >>>>> - if (key->keycode == KEY_KBDILLUMTOGGLE) >>>>> + if (key->keycode == KEY_KBDILLUMTOGGLE) { >>>>> dell_laptop_call_notifier( >>>>> DELL_LAPTOP_KBD_BACKLIGHT_BRIGHTNESS_CHANGED, NULL); >>>>> + } else if (type == 0x0011 && code == 0xe070 && remaining > 0) { >>>>> + value = !buffer[0]; >>>>> + used = 1; >>>>> + } >>>>> + >>>>> + sparse_keymap_report_entry(priv->input_dev, key, value, true); >>>>> >>>>> - sparse_keymap_report_entry(priv->input_dev, key, 1, true); >>>>> + return used; >>>>> } >>>>> >>>>> static void dell_wmi_notify(struct wmi_device *wdev, >>>>> @@ -430,21 +441,26 @@ static void dell_wmi_notify(struct wmi_device *wdev, >>>>> case 0x0000: /* One key pressed or event occurred */ >>>>> if (len > 2) >>>>> dell_wmi_process_key(wdev, buffer_entry[1], >>>>> - buffer_entry[2]); >>>>> + buffer_entry[2], >>>>> + buffer_entry + 3, >>>>> + len - 3); >>>>> /* Extended data is currently ignored */ >>>>> break; >>>>> case 0x0010: /* Sequence of keys pressed */ >>>>> case 0x0011: /* Sequence of events occurred */ >>>>> for (i = 2; i < len; ++i) >>>>> - dell_wmi_process_key(wdev, buffer_entry[1], >>>>> - buffer_entry[i]); >>>>> + i += dell_wmi_process_key(wdev, buffer_entry[1], >>>>> + buffer_entry[i], >>>>> + buffer_entry + i, >>>>> + len - i - 1); >>>>> break; >>>>> case 0x0012: >>>>> if ((len > 4) && dell_privacy_process_event(buffer_entry[1], buffer_entry[3], >>>>> buffer_entry[4])) >>>>> /* dell_privacy_process_event has handled the event */; >>>>> else if (len > 2) >>>>> - dell_wmi_process_key(wdev, buffer_entry[1], buffer_entry[2]); >>>>> + dell_wmi_process_key(wdev, buffer_entry[1], buffer_entry[2], >>>>> + buffer_entry + 3, len - 3); >>>>> break; >>>>> default: /* Unknown event */ >>>>> pr_info("Unknown WMI event type 0x%x\n", >>>>> >>>> >>> >> >
