net: wwan: t7xx: Add AP CLDMA

At this moment with the current status, t7xx is not functional due to
problems like this after connection, if there is no activity:
[ 57.370534] mtk_t7xx 0000:72:00.0: [PM] SAP suspend error: -110
[ 57.370581] mtk_t7xx 0000:72:00.0: can't suspend
(t7xx_pci_pm_runtime_suspend [mtk_t7xx] returned -110)
because after this, the traffic no longer works.

The complete series 'net: wwan: t7xx: fw flashing & coredump support'
was reverted because of issues with the pci implementation.
In order to have at least the modem working, it would be enough if just
the first commit of the series is re-applied:
d20ef656f994 net: wwan: t7xx: Add AP CLDMA
With that, the Application Processor would be controlled, correctly
suspended and the commented problems would be fixed (I am testing here
like this with no related issue).

This commit is independent of the others and not related to the
commented pci implementation for the new features: fw flashing and
coredump collection.

Use v2 patch version of d20ef656f994 as JinJian Song suggests
(https://patchwork.kernel.org/project/netdevbpf/patch/20230105154215.198828-1-m.chetan.kumar@linux.intel.com/).

Original text from the commit that would be re-applied:

d20ef656f994 net: wwan: t7xx: Add AP CLDMA
Author: Haijun Liu <haijun.liu@mediatek.com>
Date: Tue Aug 16 09:53:28 2022 +0530

The t7xx device contains two Cross Layer DMA (CLDMA) interfaces to
communicate with AP and Modem processors respectively. So far only
MD-CLDMA was being used, this patch enables AP-CLDMA.

Rename small Application Processor (sAP) to AP.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Co-developed-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Moises Veleta <moises.veleta@linux.intel.com>
Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230711062817.6108-1-jtornosm@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Revert "Merge branch 'wwan-t7xx-fw-flashing-and-coredump-support'"

This reverts commit 5417197dd516a8e115aa69f62a7b7554b0c3829c, reversing
changes made to 0630f64d25a0f0a8c6a9ce9fde8750b3b561e6f5.

Reverting to allow addressing review comments.

Link: https://lore.kernel.org/all/4c5dbea0-52a9-1c3d-7547-00ea54c90550@linux.intel.com/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: wwan: t7xx: Add AP CLDMA

The t7xx device contains two Cross Layer DMA (CLDMA) interfaces to
communicate with AP and Modem processors respectively. So far only
MD-CLDMA was being used, this patch enables AP-CLDMA.

Rename small Application Processor (sAP) to AP.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Co-developed-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Moises Veleta <moises.veleta@linux.intel.com>
Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Add control port

Control Port implements driver control messages such as modem-host
handshaking, controls port enumeration, and handles exception messages.

The handshaking process between the driver and the modem happens during
the init sequence. The process involves the exchange of a list of
supported runtime features to make sure that modem and host are ready
to provide proper feature lists including port enumeration. Further
features can be enabled and controlled in this handshaking process.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Signed-off-by: Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
Co-developed-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>