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charset=UTF-8 Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - vern.gendns.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lechnology.com X-Get-Message-Sender-Via: vern.gendns.com: authenticated_id: davidmain+lechnology.com/only user confirmed/virtual account not confirmed X-Authenticated-Sender: vern.gendns.com: davidmain@lechnology.com X-Source: X-Source-Args: X-Source-Dir: On 7/3/24 9:05 AM, Christian Eggers wrote: > Based on the existing ST7586 driver. But the ST7539 ... > - is monochrome only > - has 8 VERTICAL pixels per byte > - doesn't support any MIPI DCS commands > - has (a few) 16 bit commands > - doesn't support setting a clipping rect when writing to the RAM > - doesn't support rotation (only mirroring of X and/or Y axis) > > Questions/TODO: To start with, I would suggest reading [1]. This patch is really hard to read because it isn't properly formatted. If you don't change the patch, you can resend it as [RFC PATCH RESEND] using `git send-email`, or if you do change the patch before re-sending, e.g. because you fixed checkpatch style issues, just call it v2. [1]: https://www.kernel.org/doc/html/latest/process/submitting-patches.html > - should drivers for such old displays be mainlined? If it is actually going to be used and you are willing to maintain it, then yes. > - shall I use mipi_dbi_ although the display doesn't implement MIPI DCS > (and has some 16 bit commands)? > - can the conversion to 8 vertical pixels/byte (taken from > solomon/ssd130x.c) be avoided / simplified / made more efficient? > - how to implement setting of the display contrast (required by my > application)? I see that ssd130x_update_bl() is using brightness to control contrast. Don't know if it that is the best way though. > - add device tree binding > > Signed-off-by: Christian Eggers > ---