Kindle -- KOReader: a document reader for PDF, DJVU, EPUB, FB2, HTML, ... (GPLv3)

[pazos]

The backlight of an lcd device and the leds around an eink device are the same from the PoV of the OS.

For instance, on my linux laptop "brightnessctl" returns

Device 'intel_backlight' of class 'backlight':
	Current brightness: 100 (53%)
	Max brightness: 187

and I can set the desired brightness from 0 (off) to the max brightness specified above.

In the same vein, on a eink device with frontlight leds I can set the brightness from the minimum to the maximum.

In both cases which determines the minimum and the maximum are device drivers. In this case I can retrieve the info that's exported in sysfs with "udevadm info --attribute-walk --path=/sys/class/backlight/intel_backlight"

the result, as you can see, returns the same:

...
looking at device '/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight':
    KERNEL=="intel_backlight"
    SUBSYSTEM=="backlight"
    DRIVER==""
    ATTR{actual_brightness}=="100"
    ATTR{bl_power}=="0"
    ATTR{brightness}=="100"
    ATTR{max_brightness}=="187"
    ATTR{power/control}=="auto"
    ATTR{power/runtime_active_time}=="0"
    ATTR{power/runtime_status}=="unsupported"
    ATTR{power/runtime_suspended_time}=="0"
    ATTR{scale}=="unknown"
    ATTR{type}=="raw"
...

So, to sum up:

Kernel drivers provide our (and stock) source of truth.

It could be possible to tweak specific kernel drivers to provide more granularity in case the minimum/maximum exposed by the driver don't match the (safe) minimum/maximum the hardware is capable. The same happens with the steps between n and n+/-1 brightness.

Nobody sensible enough is going to play with this on a embedded device like the Kindle.

[kos25k]

Originally Posted by mergen3107

On most isb controller data is not active if there is no power, so the only battery-friendly option is to have ssh.

I think your option is the best.But i think i have to block system to update so to not lose jailbreak.Is there any proper way to do this?

[mergen3107]

look for renameotabin extension here. Another option is to fill up the disk space until less than 200 mb is left (e. g., with manga ).

One very dramatic way, which I can’t test since I don’t own a Kindle anymore, but I think will work, is to mess with ca-certificates to remove the Amazon-only certificates.

[kos25k]

Guys can someone help me?Which is the ideal format to read pdf's?I noticed that when format is pdf,some settings that regard view are missing,so i can't adjust the pdf to fill ok to the screen.Maybe epub or mobi?(i want as much as possible document settings)

[mgrimace]

Hello, looking for advice -
Setup: I have a KO2, jailbroken with Koreader. I have both Calibre and Calibre-web self-hosted.

Question: What’s the ‘best’ way to browse/send/manage books from my library to my Kindle, and organize them once they’re there.
- By ‘best’ I mean browsing my content, ideally with covers, and copying them wirelessly from my library to the device. Calibre-web OPDS, calibre server, calibre koreader plugin… there’s options.
- And in terms of downloading, how do folks organize the files/folders on the device. For example, I can see the in-built Kindle authors/titles on my main Koreader screen, which appear as ‘empty’ because they’re awz3/kfx…do folks put the books there? A single Koreader folder? Etc.

Thank you in advance for your setups, advice. It’s my first time using Koreader and I don’t have a good sense of the workflow on a kindle.