linux-kernel - LP8860 driver writes EEPROM on every probe

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Message-Id: <20251023150253.971072-1-dowens@ptxag.com>
Date: Thu, 23 Oct 2025 10:02:53 -0500
From: David Owens <daowens01@...il.com>
To: afd@...com
Cc: lee@...nel.org,
	linux-kernel@...r.kernel.org,
	linux-leds@...r.kernel.org,
	pavel@...nel.org
Subject: LP8860 driver writes EEPROM on every probe

I have a display device that uses the LP8860 as the backlight controller.
Recently, I switched from direct i2c writes to control brighness to using the
leds-lp8860 driver and noticed that factory provisioning was lost/over-written.
Is it correct to write to EEPROM every time lp8860 probes?  I've read that the
device can survive ~1000 EEPROM writes but I don't see that limit specifically
called out in TI's End Of Line programming guide
(https://www.ti.com/lit/an/snva797/snva797.pdf).  Even so, Writing to EEPROM
during every power cycle doesn't seem right.  I know this driver has been
around for quite a while so I hope I'm just missing something.

Any insight would be appreciated.

Thanks,
Dave