[PATCH v2 00/11] add mcf54415 DAC driver

[Angelo Dureghello]

This patchset adds a minimalistic DAC driver for the NXP mcf54415/6/7/8
ibuiltin DACs.

Currently the driver enables the raw write only. Feature as dma, sync, or
format are not supoprted for this version.

Additional options suppoerted by the DAC module will be added to the driver
later on, as needed.

The same patchset prepares the m68k/coldfire architecture to support
the driver.

Below soem basic tests done on stmark2 mcf54415-based board, voltage check
on DAC0 and DAC1:

~ # cd /sys/bus/iio/devices/iio:device0/
/sys/bus/iio/devices/iio:device0 # ls
name               out_voltage_scale  uevent
out_voltage_raw    subsystem
/sys/bus/iio/devices/iio:device0 # cat name
mcf54415
/sys/bus/iio/devices/iio:device0 # echo 4095 > out_voltage_raw 
/sys/bus/iio/devices/iio:device0 # echo 2048 > out_voltage_raw 
/sys/bus/iio/devices/iio:device0 # echo 4096 > out_voltage_raw 
sh: write error: Invalid argument
/sys/bus/iio/devices/iio:device0 # cat out_voltage_raw 
2048
/sys/bus/iio/devices/iio:device0 # 

Same behavior for /sys/bus/iio/devices/iio:device1.

Generated a sine wave by shell script, sine shape is good.

Note: this patchset depends on mew mcf_read/mcf_write implementation:
Link: https://lore.kernel.org/linux-m68k/209d0653-6386-4b64-9e15-e358f84453ab@app.fastmail.com/T/#t

---
Changes in v2:
- keeping changelog in each single patch, where any
- Link to v1: https://patch.msgid.link/20260504-wip-stmark2-dac-v1-0-874c36a4910d@baylibre.com

---
Angelo Dureghello (11):
      m68k: mcf5441x: fix clocks numbering
      m68k: mcf5441x: add clock for DAC channel 1
      m68k: mcf5441x: setup DAC clock name as per driver name
      m68k: defconfig: update stmark2 defconfig
      m68k: add DAC modules base addresses
      m68k: mcf5441x: add CCM registers
      m68k: mcf5441x: add CCR MISCCR2 bitfields
      m68k: stmark2: add mcf5441x DAC platform devices
      m68k: stmark2: use ioport.h macros for resources
      m68k: stmark2: enable DACs outputs
      iio: dac: add mcf54415 DAC

 arch/m68k/coldfire/m5441x.c         |  21 ++--
 arch/m68k/coldfire/stmark2.c        |  51 ++++++---
 arch/m68k/configs/stmark2_defconfig |   2 +
 arch/m68k/include/asm/m5441xsim.h   |  42 ++++++++
 drivers/iio/dac/Kconfig             |  10 ++
 drivers/iio/dac/Makefile            |   1 +
 drivers/iio/dac/mcf54415_dac.c      | 203 ++++++++++++++++++++++++++++++++++++
 7 files changed, 306 insertions(+), 24 deletions(-)
---
base-commit: 25c66a1b49f3c5463ee8266a3fd5256cbc794610
change-id: 20260430-wip-stmark2-dac-7060f49dd94f

Best regards,
--  
Angelo Dureghello <adureghello at baylibre.com>