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+NOTE:
+=====
+
+While the driver probes the hardware and reports itself as a
+V4L2 driver, there are still some issues preventing it to
+stream (at least it doesn't with the standard V4L2 applications.
+Didn't test yet with some custom-made app for this driver).
+Solving the related bugs and issues preventing it to work is
+needed (items 6 and 7 from the list below).
+
+TODO
+====
+
+1. The atomisp doesn't rely at the usual i2c stuff to discover the
+   sensors. Instead, it calls a function from atomisp_gmin_platform.c.
+   There are some hacks added there for it to wait for sensors to be
+   probed (with a timeout of 2 seconds or so).
+   This should be converted to the usual way, using V4L2 async subdev
+   framework to wait for cameras to be probed;
+
+2. Use ACPI _DSM table - DONE!
+
+3. Switch the driver to use pm_runtime stuff. Right now, it probes the
+   existing PMIC code and sensors call it directly.
+
+4. There's a problem at the sensor drivers: when trying to set a video
+   format, the atomisp main driver calls the sensor drivers with the
+   sensor turned off. This causes them to fail.
+
+   The only exception is the atomisp-ov2880, which has a hack inside it
+   to turn it on when VIDIOC_S_FMT is called.
+
+   The right fix seems to power on the sensor when a video device is
+   opened (or at the first VIDIOC_ ioctl - except for VIDIOC_QUERYCAP),
+   powering it down at close() syscall.
+
+   Such kind of control would need to be done inside the atomisp driver,
+   not at the sensors code.
+
+5. There are several issues related to memory management, causing
+   crashes. The atomisp splits the memory management on three separate
+   regions:
+
+	- dynamic pool;
+	- reserved pool;
+	- generic pool
+
+   The code implementing it is at:
+
+	drivers/staging/media/atomisp/pci/hmm/
+
+   It also has a separate code for managing DMA buffers at:
+
+	drivers/staging/media/atomisp/pci/mmu/
+
+   The code there is really dirty, ugly and probably wrong. I fixed
+   one bug there already, but the best would be to just trash it and use
+   something else. Maybe the code from the newer intel driver could
+   serve as a model:
+
+	drivers/staging/media/ipu3/ipu3-mmu.c
+
+   But converting it to use something like that is painful and may
+   cause some breakages.
+
+6. There is some issues at the frame receive logic, causing the
+   DQBUF ioctls to fail.
+
+7. A single AtomISP driver needs to be implemented to support both
+   Baytrail (BYT) and Cherrytail (CHT) platforms at the same time.
+   The current driver is a mechanical and hand combined merge of the
+   two using several runtime macros, plus some ifdef ISP2401 to select the
+   CHT version. Yet, there are some ISP-specific headers that change the
+   driver's behavior during compile time.
+
+8. The file structure needs to get tidied up to resemble a normal Linux
+   driver.
+
+9. Lots of the midlayer glue. unused code and abstraction needs removing.
+
+10. The AtomISP driver includes some special IOCTLS (ATOMISP_IOC_XXXX_XXXX)
+    and controls that require some cleanup. Some of those code may have
+    been removed during the cleanups. They could be needed in order to
+    properly support 3A algorithms
+
+    Such IOCTL interface needs more documentation. The better would
+    be to use something close to the interface used by the IPU3 IMGU driver.
+
+11. The ISP code has some dependencies of the exact FW version.
+    The version defined in pci/sh_css_firmware.c:
+
+    BYT (isp2400): "irci_stable_candrpv_0415_20150521_0458"
+
+    CHT (isp2401): "irci_ecr - master_20150911_0724"
+
+    Those versions don't seem to be available anymore. On the tests we've
+    done so far, this version also seems to work for CHT:
+
+		"irci_stable_candrpv_0415_20150521_0458"
+
+    Which can be obtainable from Yocto Atom ISP respository.
+
+    but this was not thoroughly tested.
+
+    At some point we may need to round up a few driver versions and see if
+    there are any specific things that can be done to fold in support for
+    multiple firmware versions.
+
+12. Switch to standard V4L2 sub-device API for sensor and lens. In
+    particular, the user space API needs to support V4L2 controls as
+    defined in the V4L2 spec and references to atomisp must be removed from
+    these drivers.
+
+13. Use LED flash API for flash LED drivers such as LM3554 (which already
+    has a LED class driver).
+
+14. Switch from videobuf1 to videobuf2. Videobuf1 is being removed!
+
+15. Correct Coding Style. Please refrain sending coding style patches
+    for this driver until the other work is done, as there will be a lot
+    of code churn until this driver becomes functional again.
+
+Limitations
+===========
+
+1. To test the patches, you also need the ISP firmware
+
+   for BYT: /lib/firmware/shisp_2400b0_v21.bin
+   for CHT: /lib/firmware/shisp_2401a0_v21.bin
+
+   The firmware files will usually be found in /etc/firmware on an Android
+   device but can also be extracted from the upgrade kit if you've managed
+   to lose them somehow.
+
+2. Without a 3A library the capture behaviour is not very good. To take a good
+   picture, you need tune ISP parameters by IOCTL functions or use a 3A library
+   such as libxcam.
+
+3. The driver is intended to drive the PCI exposed versions of the device.
+   It will not detect those devices enumerated via ACPI as a field of the
+   i915 GPU driver.
+
+   There are some patches adding i915 GPU support floating at the Yocto's
+   Aero repository (so far, untested upstream).
+
+4. The driver supports only v2 of the IPU/Camera. It will not work with the
+   versions of the hardware in other SoCs.