I am testing different RTC modules on RPi 4 running on Bullseye.
On testing DS3231, I add the module to /boot/config.txt
dtoverlay=i2c-rtc,ds3231
I can read the clock from it wihtout a problem. But when checking on the kernel log, why is it shown as ds1307?
[ 9.280219] vc4-drm gpu: bound fe206000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.280653] vc4-drm gpu: bound fe207000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.281041] vc4-drm gpu: bound fe20a000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.281404] vc4-drm gpu: bound fe216000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 9.281787] vc4-drm gpu: bound fec12000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 10.398647] rtc-ds1307 1-0068: registered as rtc0
[ 10.401252] rtc-ds1307 1-0068: setting system clock to 2022-05-10T07:21:12 UTC (1652167272)
The same happens when testing MCP7940 with the following configuration:
''' dtoverlay=i2c-rtc,mcp7940x
'''
Like when testing ds3231, the kernel log shows ds1307 instead of mcp7940x. But RTC is not feeding time and not registered at boot time. When accessing the RTC time, it returns an error:
''' hwclock: ioctl(RTC_RD_TIME) to /dev/rtc0 to read the time failed: Invalid argument' '''
Has anyone encountered the same problem?