On Thu, 27 Oct 2022 19:43:29 +0000 Barnab=C3=A1s P=C5=91cze <pobrn@xxxxxxxxxxxxxx> wrote: > Hi > > > 2022. okt=C3=B3ber 26., szerda 21:01 keltez=C3=A9ssel, Eray Or=C3=A7unus = > =C3=ADrta: > > > IdeaPads dropped support for VPCCMD_W_CAMERA somewhere between 2014-2016, > > none of the IdeaPads produced after that I tested supports it. Fortunatel= > y > > I found a way to check it; if the DSDT has camera device(s) defined, it > > shouldn't have working VPCCMD_W_CAMERA, thus camera_power shouldn't be > > exposed to sysfs. To accomplish this, walk the ACPI namespace in > > ideapad_check_features and check the devices starting with "CAM". > > Tested on 520-15IKB and Legion Y520, which successfully didn't expose > > the camera_power attribute. > >=20 > > Link: https://www.spinics.net/lists/platform-driver-x86/msg26147.html > > Signed-off-by: Eray Or=C3=A7unus <erayorcunus@xxxxxxxxx> > > --- > > drivers/platform/x86/ideapad-laptop.c | 53 ++++++++++++++++++++++++++- > > 1 file changed, 52 insertions(+), 1 deletion(-) > >=20 > > diff --git a/drivers/platform/x86/ideapad-laptop.c b/drivers/platform/x86= > /ideapad-laptop.c > > index f3d4f2beda07..65eea2e65bbe 100644 > > --- a/drivers/platform/x86/ideapad-laptop.c > > +++ b/drivers/platform/x86/ideapad-laptop.c > > @@ -149,6 +149,7 @@ struct ideapad_private { > > =09=09bool fn_lock : 1; > > =09=09bool hw_rfkill_switch : 1; > > =09=09bool kbd_bl : 1; > > +=09=09bool cam_ctrl_via_ec : 1; > > =09=09bool touchpad_ctrl_via_ec : 1; > > =09=09bool usb_charging : 1; > > =09} features; > > @@ -163,6 +164,26 @@ static bool no_bt_rfkill; > > module_param(no_bt_rfkill, bool, 0444); > > MODULE_PARM_DESC(no_bt_rfkill, "No rfkill for bluetooth."); > >=20 > > +static char *cam_device_prefix =3D "CAM"; > > + > > +static acpi_status acpi_find_device_callback(acpi_handle handle, u32 lev= > el, > > +=09=09=09=09=09 void *context, void **return_value) > > +{ > > +=09char buffer[8]; > > +=09struct acpi_buffer ret_buf; > > + > > +=09ret_buf.length =3D sizeof(buffer); > > +=09ret_buf.pointer =3D buffer; > > + > > +=09if (ACPI_SUCCESS(acpi_get_name(handle, ACPI_SINGLE_NAME, &ret_buf))) > > +=09=09if (strncmp(ret_buf.pointer, context, strlen(context)) =3D=3D 0) { > > Please use `strstarts()` here. Is there any reason why you decided not to > simply "inline" the "CAM" string here (or even in the function call)? I may use this function to find other devices in future (thus the name `acpi_find_device_callback`) and I've found a code in the kernel which use static global initialization like that, so I decided to go for it in here. But now I will create the "CAM" string inline, and I will also use `strstarts()` (I didn't know such a function existed), thank you. > > > > +=09=09=09*return_value =3D handle; > > +=09=09=09return AE_CTRL_TERMINATE; > > +=09=09} > > + > > +=09return AE_OK; > > +} > > + > > /* > > * ACPI Helpers > > */ > > @@ -675,7 +696,7 @@ static umode_t ideapad_is_visible(struct kobject *kob= > j, > > =09bool supported =3D true; > >=20 > > =09if (attr =3D=3D &dev_attr_camera_power.attr) > > -=09=09supported =3D test_bit(CFG_CAP_CAM_BIT, &priv->cfg); > > +=09=09supported =3D priv->features.cam_ctrl_via_ec; > > =09else if (attr =3D=3D &dev_attr_conservation_mode.attr) > > =09=09supported =3D priv->features.conservation_mode; > > =09else if (attr =3D=3D &dev_attr_fan_mode.attr) > > @@ -1523,10 +1544,40 @@ static const struct dmi_system_id hw_rfkill_list[= > ] =3D { > > static void ideapad_check_features(struct ideapad_private *priv) > > { > > =09acpi_handle handle =3D priv->adev->handle; > > +=09acpi_handle pci_handle; > > +=09acpi_handle temp_handle =3D NULL; > > =09unsigned long val; > > +=09acpi_status status; > > It is a small thing, but I believe it is best to define these variables > in the block of that `if` since they are not used outside of it. Ok, will do in next revision, thank you. -eray
