Hi! > > From e65b0ddbf559aa3ca8a7998404e7e67e64b705e9 Mon Sep 17 00:00:00 2001 > > From: JafarAkhondali <jafar.akhoondali@xxxxxxxxx> > > Date: Fri, 14 May 2021 08:26:47 +0430 > > Subject: [PATCH] platform/x86: acer-wmi: Add support for Acer Helios > > 300 rgb keyboard backlight > > > > The Acer helios 300 provides gaming functions WMI that is available in > > Windows, however this was not implemented in Linux. The process of finding > > the related method was done by decompiling PredatorSense(official Acer > > gaming functions software for Predator series) and decompiling WQ > > buffers. This patch provides a gaming interface which will then expose a > > character device named "acer-gkbbl". This character device accepts 16 > > bytes long config, which is specific for the backlight method. The > > meaning of each bytes ordered by bit position is as follows: > > > > Bit 0 -> Backlight modes: > > 1: Breath > > 2: Neon > > 3: Wave > > 4: Shifting > > 5: Zoom > > Bit 1 -> Animation Speed: from 1 to 9 ( 1 is slowest, 9 is fastest) > > Bit 2 -> Brightness from 0 to 100 ( 0 is no backlight, 100 is brightest) > > Bit 3 -> Unknown. Wave effect uses 8, other modes must use 0 > > Bit 4 -> Animation Direction: > > 1: Right-to-Left > > 2: Left-to-Right > > Bit 5 -> Red Color Selection > > Bit 6 -> Green Color Selection > > Bit 7 -> Blue Color Selection > > Bit 8 -> Currently unknown, or not used in known model > > Bit 9 -> Currently unknown, or not used in known model > > Bit 10 -> Currently unknown, or not used in known model > > Bit 11 -> Currently unknown, or not used in known model > > Bit 12 -> Currently unknown, or not used in known model > > Bit 13 -> Currently unknown, or not used in known model > > Bit 14 -> Currently unknown, or not used in known model > > Bit 15 -> Currently unknown, or not used in known model > > > > Filling this config is out of scope for the kernel module, and this module > > only acts as an interface. > > > > Currently, I'm not sure with the method for communicating with user-space, > > but since leds.h subsystem wouldn't fit for complex actions such as this > > complex config, I couldn't find any better method than char dev. > > Thank you for your patch, given that there is no existing kernel > interface which is a good match for the features exported by this > keyboard I'm fine with just having a raw interface where userspace > writes GAMING_KBBL_CONFIG_LEN bytes as you suggest. Keyboard backlight goes through LED interface (so please cc the mailing list) and no, passing raw bytes to hardware is not an acceptable interface. > But lets not use a classdev + chardev for this please, you can > just add a binary write-only sysfs-atrribute under the wmi-dev for > this with a name like (for example) gaming_kbd_backlight_config > and then userspace can write to that without needing a class + char > dev just for this single write. NAK. We have existing interfaces for this. Best regards, Pavel
