[WIP] Allow Host Access any Marlin attached SD

Marlin/Configuration_adv.h

@@ -1662,6 +1662,15 @@
  */
 //#define NO_SD_HOST_DRIVE   // Disable SD Card access over USB (for security).
 
+/**
+ * By default the framework is responsible for the shared media I/O.
+ * Enable this if you need Marlin to take care of the shared media I/O.
+ * Useful if shared media isn't working properly on some boards.
+ */
+#if ENABLED(SDSUPPORT) && DISABLED(NO_SD_HOST_DRIVE)
+  //#define DISKIO_HOST_DRIVE
+#endif
+
 /**
  * Additional options for Graphical Displays
  *

Marlin/src/HAL/LPC1768/diskio.cpp

@@ -0,0 +1,130 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifdef TARGET_LPC1768
+
+#include "../../inc/MarlinConfig.h"
+
+#if BOTH(SDSUPPORT, DISKIO_HOST_DRIVE)
+
+// Overwrite DiskIO functions from LPC framework to use Marlin Sd2Card API.
+#include <chanfs/diskio.h>
+#include "../../sd/cardreader.h"
+
+DRESULT disk_read (
+  BYTE drv,     // Physical drive number (0)
+  BYTE *buff,   // Pointer to the data buffer to store read data
+  DWORD sector, // Start sector number (LBA)
+  UINT count    // Number of sectors to read (1..128)
+) {
+  auto sd2card = card.getSd2Card();
+  if (count == 1) {
+    sd2card.readBlock(sector, buff);
+    return RES_OK;
+  }
+
+  sd2card.readStart(sector);
+  while (count--) {
+    sd2card.readData(buff);
+    buff += 512;
+  }
+  sd2card.readStop();
+  return RES_OK;
+}
+
+DSTATUS disk_status(BYTE drv) {    // Physical drive number (0)
+  return 0;
+}
+
+DSTATUS disk_initialize(BYTE drv) {    // Physical drive number (0)
+  // If already mounted, it's already initialized!
+  if (!card.isMounted()) {
+    auto sd2card = card.getSd2Card();
+    if (!sd2card.init(SPI_SPEED, SDSS)
+      #if defined(LCD_SDSS) && (LCD_SDSS != SDSS)
+        && !sd2card.init(SPI_SPEED, LCD_SDSS)
+      #endif
+    ) {
+      return RES_ERROR;
+    }
+  }
+
+  return RES_OK;
+}
+
+#if _DISKIO_WRITE
+
+  DRESULT disk_write(
+    BYTE drv,         // Physical drive number (0)
+    const BYTE *buff, // Ponter to the data to write
+    DWORD sector,     // Start sector number (LBA)
+    UINT count        // Number of sectors to write (1..128)
+  ) {
+    auto sd2card = card.getSd2Card();
+    if (count == 1) {
+      sd2card.writeBlock(sector, buff);
+      return RES_OK;
+    }
+
+    sd2card.writeStart(sector, count);
+    while (count--) {
+      sd2card.writeData(buff);
+      buff += 512;
+    }
+    sd2card.writeStop();
+    return RES_OK;
+  }
+
+#endif // _DISKIO_WRITE
+
+#if _DISKIO_IOCTL
+
+  DRESULT disk_ioctl(
+    BYTE drv,   // Physical drive number (0)
+    BYTE cmd,   // Control command code
+    void *buff  // Pointer to the conrtol data
+  ) {
+    DWORD *dp, st, ed;
+
+    auto sd2card = card.getSd2Card();
+    switch (cmd) {
+      case CTRL_SYNC:         // Wait for end of internal write process of the drive
+      break;
+      case GET_SECTOR_COUNT:  // Get drive capacity in unit of sector (DWORD)
+        *(int32_t*)buff = sd2card.cardSize();
+      break;
+      case GET_BLOCK_SIZE:    // Get erase block size in unit of sector (DWORD)
+      break;
+      case CTRL_TRIM:         // Erase a block of sectors (used when _USE_TRIM in ffconf.h is 1)
+        dp = (DWORD*)buff; st = dp[0]; ed = dp[1];        // Load sector block
+        sd2card.erase(st, ed);
+      break;
+    }
+
+    return RES_OK;
+  }
+
+#endif // _DISKIO_IOCTL
+
+#endif // SDSUPPORT && DISKIO_HOST_DRIVE
+
+#endif // TARGET_LPC1768

Marlin/src/inc/SanityCheck.h

@@ -786,6 +786,25 @@ static_assert(Y_MAX_LENGTH >= Y_BED_SIZE, "Movement bounds (Y_MIN_POS, Y_MAX_POS
   #endif
 #endif
 
+#ifndef TARGET_LPC1768
+  #if ANY( \
+      ENDSTOPPULLDOWNS, \
+      ENDSTOPPULLDOWN_XMIN, ENDSTOPPULLDOWN_XMAX, \
+      ENDSTOPPULLDOWN_YMIN, ENDSTOPPULLDOWN_YMAX, \
+      ENDSTOPPULLDOWN_ZMIN, ENDSTOPPULLDOWN_ZMAX, \
+      ENDSTOPPULLDOWN_IMIN, ENDSTOPPULLDOWN_IMAX, \
+      ENDSTOPPULLDOWN_JMIN, ENDSTOPPULLDOWN_JMAX, \
+      ENDSTOPPULLDOWN_KMIN, ENDSTOPPULLDOWN_KMAX, \
+      ENDSTOPPULLDOWN_UMIN, ENDSTOPPULLDOWN_UMAX, \
+      ENDSTOPPULLDOWN_VMIN, ENDSTOPPULLDOWN_VMAX, \
+      ENDSTOPPULLDOWN_WMIN, ENDSTOPPULLDOWN_WMAX \
+    )
+    #error "PULLDOWN pin mode is not available on the selected board."
+  #elif BOTH(SDSUPPORT, DISKIO_HOST_DRIVE)
+    #error "DISKIO_HOST_DRIVE is not available on the selected board."
+  #endif
+#endif
+
 #if BOTH(ENDSTOPPULLUPS, ENDSTOPPULLDOWNS)
   #error "Enable only one of ENDSTOPPULLUPS or ENDSTOPPULLDOWNS."
 #elif BOTH(FIL_RUNOUT_PULLUP, FIL_RUNOUT_PULLDOWN)