Hi Luke, Thank you for your patch. For the next version please don't forget to Cc: platform-driver-x86@xxxxxxxxxxxxxxx On 8/28/23 01:23, Luke D. Jones wrote: > Add support for the WMI methods used to turn off and adjust the > brightness of the secondary "screenpad" device found on some high-end > ASUS laptops like the GX650P series and others. > > These methods are utilised in a new backlight device named asus_screenpad. You have quite a bit of useful extra info in your cover-letter, for the next version please add a copy of that info to your commit message. > > Signed-off-by: Luke D. Jones <luke@xxxxxxxxxx> > --- > drivers/platform/x86/asus-wmi.c | 131 +++++++++++++++++++++ > drivers/platform/x86/asus-wmi.h | 1 + > include/linux/platform_data/x86/asus-wmi.h | 4 + > 3 files changed, 136 insertions(+) > > diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c > index 13547e55ae82..2801c691133a 100644 > --- a/drivers/platform/x86/asus-wmi.c > +++ b/drivers/platform/x86/asus-wmi.c > @@ -25,6 +25,7 @@ > #include <linux/input/sparse-keymap.h> > #include <linux/kernel.h> > #include <linux/leds.h> > +#include <linux/minmax.h> > #include <linux/module.h> > #include <linux/pci.h> > #include <linux/pci_hotplug.h> > @@ -127,6 +128,9 @@ module_param(fnlock_default, bool, 0444); > #define NVIDIA_TEMP_MIN 75 > #define NVIDIA_TEMP_MAX 87 > > +#define ASUS_SCREENPAD_BRIGHT_MIN 20 Hmm, in the coverletter you talk about 15 as min value and 60 as default value when the value read back from the hw at probe() time is < min. I'm fine with using 20 instead of 15, but the whole "The compromise was to set the brightness to 60 which is a usable brightness if the module init brightness was under 15." thing from your cover letter seems to be missing. > +#define ASUS_SCREENPAD_BRIGHT_MAX 255 > + > static const char * const ashs_ids[] = { "ATK4001", "ATK4002", NULL }; > > static int throttle_thermal_policy_write(struct asus_wmi *); > @@ -212,6 +216,7 @@ struct asus_wmi { > > struct input_dev *inputdev; > struct backlight_device *backlight_device; > + struct backlight_device *screenpad_backlight_device; > struct platform_device *platform_device; > > struct led_classdev wlan_led; > @@ -3776,6 +3781,123 @@ static int is_display_toggle(int code) > return 0; > } > > +/* Screenpad backlight *******************************************************/ > + > +static int read_screenpad_backlight_power(struct asus_wmi *asus) > +{ > + int ret; > + > + ret = asus_wmi_get_devstate_simple(asus, ASUS_WMI_DEVID_SCREENPAD_POWER); > + if (ret < 0) > + return ret; > + /* 1 == powered */ > + return ret ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN; > +} > + > +static int read_screenpad_brightness(struct backlight_device *bd) > +{ > + struct asus_wmi *asus = bl_get_data(bd); > + u32 retval; > + int err; > + > + err = read_screenpad_backlight_power(asus); > + if (err < 0) > + return err; > + /* The device brightness can only be read if powered, so return stored */ > + if (err == FB_BLANK_POWERDOWN) > + return asus->driver->screenpad_brightness; You are missing a " - ASUS_SCREENPAD_BRIGHT_MIN" here (you do add it when storing values to asus->driver->screenpad_brightness in update_screenpad_bl_status()). > + > + err = asus_wmi_get_devstate(asus, ASUS_WMI_DEVID_SCREENPAD_LIGHT, &retval); > + if (err < 0) > + return err; > + > + return (retval & ASUS_WMI_DSTS_BRIGHTNESS_MASK) - ASUS_SCREENPAD_BRIGHT_MIN; > +} > + > +static int update_screenpad_bl_status(struct backlight_device *bd) > +{ > + struct asus_wmi *asus = bl_get_data(bd); > + int power, err = 0; > + u32 ctrl_param; > + > + power = read_screenpad_backlight_power(asus); > + if (power < 0) > + return power; > + > + if (bd->props.power != power) { > + if (power != FB_BLANK_UNBLANK) { > + /* Only brightness > 0 can power it back on */ > + ctrl_param = max(ASUS_SCREENPAD_BRIGHT_MIN, asus->driver->screenpad_brightness); Not sure you need the max() here, I don't think you ever store a value below ASUS_SCREENPAD_BRIGHT_MIN in driver->screenpad_brightness ? > + err = asus_wmi_set_devstate(ASUS_WMI_DEVID_SCREENPAD_LIGHT, > + ctrl_param, NULL); > + } else { > + err = asus_wmi_set_devstate(ASUS_WMI_DEVID_SCREENPAD_POWER, 0, NULL); > + } > + } else if (power == FB_BLANK_UNBLANK) { > + /* Only set brightness if powered on or we get invalid/unsync state */ > + ctrl_param = bd->props.brightness + ASUS_SCREENPAD_BRIGHT_MIN; > + err = asus_wmi_set_devstate(ASUS_WMI_DEVID_SCREENPAD_LIGHT, ctrl_param, NULL); > + } > + Not sure if you should update screenpad_brightness here on errors ? Maybe add a "if (err == 0)" as condition ? > + /* Ensure brightness is stored to turn back on with */ > + asus->driver->screenpad_brightness = bd->props.brightness + ASUS_SCREENPAD_BRIGHT_MIN; So screenpad_brightness is never below ASUS_SCREENPAD_BRIGHT_MIN here. > + > + return err; > +} > + > +static const struct backlight_ops asus_screenpad_bl_ops = { > + .get_brightness = read_screenpad_brightness, > + .update_status = update_screenpad_bl_status, > + .options = BL_CORE_SUSPENDRESUME, > +}; > + > +static int asus_screenpad_init(struct asus_wmi *asus) > +{ > + struct backlight_device *bd; > + struct backlight_properties props; > + int err, power; > + int brightness = 0; > + > + power = read_screenpad_backlight_power(asus); > + if (power < 0) > + return power; > + > + if (power != FB_BLANK_POWERDOWN) { > + err = asus_wmi_get_devstate(asus, ASUS_WMI_DEVID_SCREENPAD_LIGHT, &brightness); > + if (err < 0) > + return err; > + } > + /* default to an acceptable min brightness on boot if too low */ > + if (brightness < ASUS_SCREENPAD_BRIGHT_MIN) > + brightness = ASUS_SCREENPAD_BRIGHT_MIN; brightness = ASUS_SCREENPAD_BRIGHT_DEFAULT; Instead (new define for "60") ? > + > + memset(&props, 0, sizeof(struct backlight_properties)); > + props.type = BACKLIGHT_RAW; /* ensure this bd is last to be picked */ > + props.max_brightness = ASUS_SCREENPAD_BRIGHT_MAX - ASUS_SCREENPAD_BRIGHT_MIN; > + bd = backlight_device_register("asus_screenpad", > + &asus->platform_device->dev, asus, > + &asus_screenpad_bl_ops, &props); > + if (IS_ERR(bd)) { > + pr_err("Could not register backlight device\n"); > + return PTR_ERR(bd); > + } > + > + asus->screenpad_backlight_device = bd; > + asus->driver->screenpad_brightness = brightness; > + bd->props.brightness = brightness; And you've checked brightness against ASUS_SCREENPAD_BRIGHT_MIN above, so screenpad_brightness is never below ASUS_SCREENPAD_BRIGHT_MIN here either. Otherwise this looks good to me. Regards, Hans > + bd->props.power = power; > + backlight_update_status(bd); > + > + return 0; > +} > + > +static void asus_screenpad_exit(struct asus_wmi *asus) > +{ > + backlight_device_unregister(asus->screenpad_backlight_device); > + > + asus->screenpad_backlight_device = NULL; > +} > + > /* Fn-lock ********************************************************************/ > > static bool asus_wmi_has_fnlock_key(struct asus_wmi *asus) > @@ -4431,6 +4553,12 @@ static int asus_wmi_add(struct platform_device *pdev) > } else if (asus->driver->quirks->wmi_backlight_set_devstate) > err = asus_wmi_set_devstate(ASUS_WMI_DEVID_BACKLIGHT, 2, NULL); > > + if (asus_wmi_dev_is_present(asus, ASUS_WMI_DEVID_SCREENPAD_LIGHT)) { > + err = asus_screenpad_init(asus); > + if (err && err != -ENODEV) > + goto fail_screenpad; > + } > + > if (asus_wmi_has_fnlock_key(asus)) { > asus->fnlock_locked = fnlock_default; > asus_wmi_fnlock_update(asus); > @@ -4454,6 +4582,8 @@ static int asus_wmi_add(struct platform_device *pdev) > asus_wmi_backlight_exit(asus); > fail_backlight: > asus_wmi_rfkill_exit(asus); > +fail_screenpad: > + asus_screenpad_exit(asus); > fail_rfkill: > asus_wmi_led_exit(asus); > fail_leds: > @@ -4480,6 +4610,7 @@ static int asus_wmi_remove(struct platform_device *device) > asus = platform_get_drvdata(device); > wmi_remove_notify_handler(asus->driver->event_guid); > asus_wmi_backlight_exit(asus); > + asus_screenpad_exit(asus); > asus_wmi_input_exit(asus); > asus_wmi_led_exit(asus); > asus_wmi_rfkill_exit(asus); > diff --git a/drivers/platform/x86/asus-wmi.h b/drivers/platform/x86/asus-wmi.h > index a478ebfd34df..5fbdd0eafa02 100644 > --- a/drivers/platform/x86/asus-wmi.h > +++ b/drivers/platform/x86/asus-wmi.h > @@ -57,6 +57,7 @@ struct quirk_entry { > struct asus_wmi_driver { > int brightness; > int panel_power; > + int screenpad_brightness; > int wlan_ctrl_by_user; > > const char *name; > diff --git a/include/linux/platform_data/x86/asus-wmi.h b/include/linux/platform_data/x86/asus-wmi.h > index 16e99a1c37fc..63e630276499 100644 > --- a/include/linux/platform_data/x86/asus-wmi.h > +++ b/include/linux/platform_data/x86/asus-wmi.h > @@ -58,6 +58,10 @@ > #define ASUS_WMI_DEVID_KBD_BACKLIGHT 0x00050021 > #define ASUS_WMI_DEVID_LIGHT_SENSOR 0x00050022 /* ?? */ > #define ASUS_WMI_DEVID_LIGHTBAR 0x00050025 > +/* This can only be used to disable the screen, not re-enable */ > +#define ASUS_WMI_DEVID_SCREENPAD_POWER 0x00050031 > +/* Writing a brightness re-enables the screen if disabled */ > +#define ASUS_WMI_DEVID_SCREENPAD_LIGHT 0x00050032 > #define ASUS_WMI_DEVID_FAN_BOOST_MODE 0x00110018 > #define ASUS_WMI_DEVID_THROTTLE_THERMAL_POLICY 0x00120075 >