Add usbsdmux support

Kconfig

@@ -135,8 +135,8 @@ config CONSOLE_VARIANT
     string "Console variant"
     default "qemu"
     help
-      Select a shared storage variant from 'docker', 'qemu', 'samsung'
-      and 'usbf'.
+      Select a shared storage variant from 'docker', 'qemu', 'samsung',
+      'usbsdmux' and 'usbf'.
 endmenu
 
 menu "Video Settings"

docs/config.rst

@@ -128,8 +128,8 @@ General settings
     selected with ``variant``.
 
   * ``variant``: string [required]
-      Select a shared storage variant from ``docker``, ``qemu``, ``samsung``
-      and ``usbf``.
+      Select a shared storage variant from ``docker``, ``qemu``, ``samsung``,
+      ``usbsdmux`` and ``usbf``.
 
 * ``usb``: section [optional]
     Specify how many USB ports may be controlled from this agent.
@@ -388,6 +388,21 @@ a SD card between the DUT and host. The following settings are supported:
   Identifier of the sdmux/sdwire device to use. Use ``sd-mux-ctrl`` to list
   available devices. When not specified, the first device is auto-detected.
 
+``usbsdmux`` driver settings
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The ``usbsdmux`` driver supports SD card switcher based on the Microchip
+USB2642 card reader chip. A tool with this name is available for several
+distributions and via pip. The following settings are supported:
+
+* ``device``: string [optional]
+  Block device for the shared storage as seen on the host (defaults to
+  ``/dev/sda``)
+
+* ``control-device``: string [optional]
+  Control device used for talking to the switcher on the host (defaults to
+  ``/dev/sg0``)
+
 ``usbf`` driver settings
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

meta-isar/recipes-core/images/mtda-image.bb

@@ -54,6 +54,7 @@ IMAGE_PREINSTALL += "                    \
     ssh                                  \
     sudo                                 \
     systemd-timesyncd                    \
+    usbsdmux                             \
     vim                                  \
     wireless-regdb                       \
     wireless-tools                       \

mtda.ini

@@ -159,6 +159,7 @@ variant=aviosys_8800
 #    - docker 
 #    - qemu
 #    - samsung
+#    - usbsdmux
 #    - usbf
 # ---------------------------------------------------------------------------
 # Note: this section is ignored when connecting to a remote agent

mtda/storage/qemu.py

@@ -33,7 +33,7 @@ def configure(self, conf):
         self.mtda.debug(3, "storage.qemu.configure()")
         self.lock.acquire()
 
-        result = None
+        result = True
         if 'file' in conf:
             self.file = os.path.realpath(conf['file'])
         d = os.path.dirname(self.file)

mtda/storage/usbsdmux.py

@@ -0,0 +1,114 @@
+# ---------------------------------------------------------------------------
+# Storage driver for usbsdmux on MTDA
+# ---------------------------------------------------------------------------
+#
+# This software is a part of MTDA.
+# Copyright (C) 2024 Siemens AG
+#
+# ---------------------------------------------------------------------------
+# SPDX-License-Identifier: MIT
+# ---------------------------------------------------------------------------
+
+# System imports
+import subprocess
+
+# Local imports
+import mtda.constants as CONSTS
+from mtda.storage.helpers.image import Image
+
+
+class UsbSdMuxStorageController(Image):
+
+    def __init__(self, mtda):
+        super().__init__(mtda)
+        self.file = "/dev/sda"
+        self.control_device = "/dev/sg0"
+
+    """ Configure this storage controller from the provided configuration"""
+    def configure(self, conf):
+        self.mtda.debug(3, "storage.usbsdmux.configure()")
+
+        result = True
+        if 'device' in conf:
+            self.file = conf['device']
+        if 'control-device' in conf:
+            self.control_device = conf['control-device']
+        self.mtda.debug(3, f"storage.usbsdmux.configure(): {str(result)}")
+        return result
+
+    """ Check presence of the sdmux"""
+    def probe(self):
+        self.mtda.debug(3, "storage.usbsdmux.probe()")
+
+        result = True
+        try:
+            subprocess.check_output([
+                "usbsdmux", self.control_device, "get"
+            ])
+        except subprocess.CalledProcessError:
+            result = False
+
+        self.mtda.debug(3, f"storage.usbsdmux.probe(): {str(result)}")
+        return result
+
+    """ Attach the SD card to the host"""
+    def to_host(self):
+        self.mtda.debug(3, "storage.usbsdmux.to_host()")
+
+        result = True
+        try:
+            subprocess.check_output([
+                "usbsdmux", self.control_device, "host"
+            ])
+        except subprocess.CalledProcessError:
+            result = False
+
+        self.mtda.debug(3, f"storage.usbsdmux.to_host(): {str(result)}")
+        return result
+
+    """ Attach the SD card to the target"""
+    def to_target(self):
+        self.mtda.debug(3, "storage.usbsdmux.to_target()")
+        self.lock.acquire()
+
+        result = self._close()
+        if result is True:
+            result = self._umount()
+        if result is True:
+            try:
+                subprocess.check_output([
+                    "usbsdmux", self.control_device, "dut"
+                ])
+            except subprocess.CalledProcessError:
+                result = False
+
+        self.mtda.debug(3, f"storage.usbsdmux.to_target(): {str(result)}")
+        self.lock.release()
+        return result
+
+    """ Determine where is the SD card attached"""
+    def _status(self):
+        self.mtda.debug(3, "storage.usbsdmux.status()")
+
+        try:
+            status = subprocess.check_output([
+                "usbsdmux", self.control_device, "get"
+            ]).decode("utf-8").splitlines()
+            result = CONSTS.STORAGE.UNKNOWN
+            for s in status:
+                if s == "host":
+                    result = CONSTS.STORAGE.ON_HOST
+                    break
+                elif s == "dut":
+                    result = CONSTS.STORAGE.ON_TARGET
+                    break
+        except subprocess.CalledProcessError:
+            self.mtda.debug(1, "storage.usbsdmux.status(): usbsdmux failed!")
+            result = CONSTS.STORAGE.UNKNOWN
+
+        self.mtda.debug(3, f"storage.usbsdmux.status(): {str(result)}")
+        return result
+
+
+def instantiate(mtda):
+    return UsbSdMuxStorageController(mtda)