ide-usb/Core/Src/usb.c

#include "tusb.h"
#include "ide_async.h"

// Invoked to determine max LUN
uint8_t tud_msc_get_maxlun_cb(void) {
	return 1;
}

// Invoked when received SCSI_CMD_INQUIRY
// Application fill vendor id, product id and revision with string up to 8, 16, 4 characters respectively
void tud_msc_inquiry_cb(uint8_t lun, uint8_t vendor_id[8], uint8_t product_id[16], uint8_t product_rev[4]) {
	const char vid[] = "Sweproj";
	const char pid[] = "IDEUSB adapter";
	const char rev[] = "1.0";

	memcpy(vendor_id  , vid, strlen(vid));
	memcpy(product_id , pid, strlen(pid));
	memcpy(product_rev, rev, strlen(rev));
}

// Invoked when received Test Unit Ready command.
// return true allowing host to read/write this LUN e.g SD card inserted
bool tud_msc_test_unit_ready_cb(uint8_t lun) {
	return true;
}

// Invoked when received SCSI_CMD_READ_CAPACITY_10 and SCSI_CMD_READ_FORMAT_CAPACITY to determine the disk size
// Application update block count and block size
void tud_msc_capacity_cb(uint8_t lun, uint32_t* block_count, uint16_t* block_size) {
	*block_count = ide_async_get_num_sectors();
	*block_size  = 512;
}

// Invoked when received Start Stop Unit command
// - Start = 0 : stopped power mode, if load_eject = 1 : unload disk storage
// - Start = 1 : active mode, if load_eject = 1 : load disk storage
bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, bool load_eject) {
	return true;
}

// Callback invoked when received READ10 command.
// Copy disk's data to buffer (up to bufsize) and return number of copied bytes.
int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void* buffer, uint32_t bufsize) {
	return ide_async_read(lba, offset, buffer, bufsize);
}

// Callback invoked when received WRITE10 command.
// Process data in buffer to disk's storage and return number of written bytes
int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t* buffer, uint32_t bufsize) {
	return ide_async_write(lba, offset, buffer, bufsize);
}

// Callback invoked when received an SCSI command not in built-in list below
// - READ_CAPACITY10, READ_FORMAT_CAPACITY, INQUIRY, MODE_SENSE6, REQUEST_SENSE
// - READ10 and WRITE10 has their own callbacks
int32_t tud_msc_scsi_cb (uint8_t lun, uint8_t const scsi_cmd[16], void* buffer, uint16_t bufsize) {
	// read10 & write10 has their own callback and MUST not be handled here

	void const* response = NULL;
	uint16_t resplen = 0;

	// most scsi handled is input
	bool in_xfer = true;

	switch (scsi_cmd[0]) {
	case SCSI_CMD_PREVENT_ALLOW_MEDIUM_REMOVAL:
		// Host is about to read/write etc ... better not to disconnect disk
		resplen = 0;
		break;

	case SCSI_CMD_START_STOP_UNIT:
		// Host try to eject/safe remove/poweroff us. We could safely disconnect with disk storage, or go into lower power
		/* scsi_start_stop_unit_t const * start_stop = (scsi_start_stop_unit_t const *) scsi_cmd;
		// Start bit = 0 : low power mode, if load_eject = 1 : unmount disk storage as well
		// Start bit = 1 : Ready mode, if load_eject = 1 : mount disk storage
		start_stop->start;
		start_stop->load_eject;
		*/
		resplen = 0;
		break;

	default:
		// Set Sense = Invalid Command Operation
		tud_msc_set_sense(lun, SCSI_SENSE_ILLEGAL_REQUEST, 0x20, 0x00);

		// negative means error -> tinyusb could stall and/or response with failed status
		resplen = -1;
		break;
	}

	// return resplen must not larger than bufsize
	if (resplen > bufsize) resplen = bufsize;

	if (response && (resplen > 0)) {
		if(in_xfer) {
			memcpy(buffer, response, resplen);
		} else {
			// SCSI output
		}
	}

	return resplen;
}