[PATCH] docs: organize subsystems

[Costa Shulyupin]

as requested.

Add classes:
* Core subsystems
* Storage interfaces
* Networking interfaces
* Peripherals interfaces
* Embedded interfaces
* Other subsystems

Signed-off-by: Costa Shulyupin <costa.shul@xxxxxxxxxx>
---
 Documentation/subsystem-apis.rst | 87 +++++++++++++++++++++++---------
 1 file changed, 64 insertions(+), 23 deletions(-)

diff --git a/Documentation/subsystem-apis.rst b/Documentation/subsystem-apis.rst
index 55c90d5383ef..20655f6092c2 100644
--- a/Documentation/subsystem-apis.rst
+++ b/Documentation/subsystem-apis.rst
@@ -10,6 +10,22 @@ is taken directly from the kernel source, with supplemental material added
 as needed (or at least as we managed to add it — probably *not* all that is
 needed).
 
+Core subsystems
+---------------
+
+.. toctree::
+   :maxdepth: 1
+
+   core-api/index
+   driver-api/index
+   scheduler/index
+   timers/index
+   locking/index
+   cpu-freq/index
+   mm/index
+   power/index
+
+
 Human interfaces
 ----------------
 
@@ -22,46 +38,71 @@ Human interfaces
    gpu/index
    fb/index
 
-**Fixme**: much more organizational work is needed here.
+
+Storage interfaces
+------------------
 
 .. toctree::
    :maxdepth: 1
 
-   driver-api/index
-   core-api/index
-   locking/index
-   accounting/index
+   filesystems/index
    block/index
    cdrom/index
-   cpu-freq/index
-   fpga/index
-   i2c/index
-   iio/index
+   scsi/index
+   target/index
+
+
+Networking interfaces
+---------------------
+
+.. toctree::
+   :maxdepth: 1
+
    isdn/index
    infiniband/index
-   leds/index
    netlabel/index
    networking/index
-   pcmcia/index
-   power/index
-   target/index
-   timers/index
+   mhi/index
+
+
+Peripherals interfaces
+----------------------
+
+.. toctree::
+   :maxdepth: 1
+
+   usb/index
+   PCI/index
+   hwmon/index
+   leds/index
+
+
+Embedded interfaces
+-------------------
+
+.. toctree::
+   :maxdepth: 1
+
+   fpga/index
+   i2c/index
+   iio/index
    spi/index
    w1/index
+   peci/index
+
+Other subsystems
+----------------
+
+.. toctree::
+   :maxdepth: 1
+
+   accounting/index
+   pcmcia/index
    watchdog/index
    virt/index
-   hwmon/index
    accel/index
    security/index
    crypto/index
-   filesystems/index
-   mm/index
    bpf/index
-   usb/index
-   PCI/index
-   scsi/index
    misc-devices/index
-   scheduler/index
-   mhi/index
-   peci/index
    wmi/index
-- 
2.40.1