--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mmc.c	Tue May 08 22:51:38 2012 +0800
@@ -0,0 +1,612 @@
+/*-----------------------------------------------------------------------*/
+/* MMCv3/SDv1/SDv2 (in SPI mode) control module  (C)ChaN, 2010           */
+/*-----------------------------------------------------------------------*/
+/* Only rcvr_spi(), xmit_spi(), disk_timerproc() and some macros         */
+/* are platform dependent.                                               */
+/*-----------------------------------------------------------------------*/
+
+
+#include <avr/io.h>
+#include "diskio.h"
+
+
+/*--------------------------------------------------------------------------
+
+   Module Private Functions
+
+---------------------------------------------------------------------------*/
+
+/* Port Controls  (Platform dependent) */
+#define CS_LOW()	PORTB &= ~1			/* MMC CS = L */
+#define	CS_HIGH()	PORTB |= 1			/* MMC CS = H */
+#define SOCKWP		(PINB & 0x20)		/* Write protected. yes:true, no:false, default:false */
+#define SOCKINS		(!(PINB & 0x10))	/* Card detected.   yes:true, no:false, default:true */
+
+#define	FCLK_SLOW()	SPCR = 0x52		/* Set slow clock (100k-400k) */
+#define	FCLK_FAST()	SPCR = 0x50		/* Set fast clock (depends on the CSD) */
+
+
+/* Definitions for MMC/SDC command */
+#define CMD0	(0)			/* GO_IDLE_STATE */
+#define CMD1	(1)			/* SEND_OP_COND (MMC) */
+#define	ACMD41	(0x80+41)	/* SEND_OP_COND (SDC) */
+#define CMD8	(8)			/* SEND_IF_COND */
+#define CMD9	(9)			/* SEND_CSD */
+#define CMD10	(10)		/* SEND_CID */
+#define CMD12	(12)		/* STOP_TRANSMISSION */
+#define ACMD13	(0x80+13)	/* SD_STATUS (SDC) */
+#define CMD16	(16)		/* SET_BLOCKLEN */
+#define CMD17	(17)		/* READ_SINGLE_BLOCK */
+#define CMD18	(18)		/* READ_MULTIPLE_BLOCK */
+#define CMD23	(23)		/* SET_BLOCK_COUNT (MMC) */
+#define	ACMD23	(0x80+23)	/* SET_WR_BLK_ERASE_COUNT (SDC) */
+#define CMD24	(24)		/* WRITE_BLOCK */
+#define CMD25	(25)		/* WRITE_MULTIPLE_BLOCK */
+#define CMD55	(55)		/* APP_CMD */
+#define CMD58	(58)		/* READ_OCR */
+
+/* Card type flags (CardType) */
+#define CT_MMC		0x01		/* MMC ver 3 */
+#define CT_SD1		0x02		/* SD ver 1 */
+#define CT_SD2		0x04		/* SD ver 2 */
+#define CT_SDC		(CT_SD1|CT_SD2)	/* SD */
+#define CT_BLOCK	0x08		/* Block addressing */
+
+
+static volatile
+DSTATUS Stat = STA_NOINIT;	/* Disk status */
+
+static volatile
+BYTE Timer1, Timer2;	/* 100Hz decrement timer */
+
+static
+BYTE CardType;			/* Card type flags */
+
+
+/*-----------------------------------------------------------------------*/
+/* Transmit a byte to MMC via SPI  (Platform dependent)                  */
+/*-----------------------------------------------------------------------*/
+
+#define xmit_spi(dat) 	SPDR=(dat); loop_until_bit_is_set(SPSR,SPIF)
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Receive a byte from MMC via SPI  (Platform dependent)                 */
+/*-----------------------------------------------------------------------*/
+
+static
+BYTE rcvr_spi (void)
+{
+	SPDR = 0xFF;
+	loop_until_bit_is_set(SPSR, SPIF);
+	return SPDR;
+}
+
+/* Alternative macro to receive data fast */
+#define rcvr_spi_m(dst)	SPDR=0xFF; loop_until_bit_is_set(SPSR,SPIF); *(dst)=SPDR
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Wait for card ready                                                   */
+/*-----------------------------------------------------------------------*/
+
+static
+int wait_ready (void)	/* 1:OK, 0:Timeout */
+{
+	BYTE d;
+
+
+	Timer2 = 50;	/* Wait for ready in timeout of 500ms */
+	do
+		d = rcvr_spi();
+	while (d != 0xFF && Timer2);
+
+	return (d == 0xFF) ? 1 : 0;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Deselect the card and release SPI bus                                 */
+/*-----------------------------------------------------------------------*/
+
+static
+void deselect (void)
+{
+	CS_HIGH();
+	rcvr_spi();	/* Dummy clock (force DO hi-z for multiple slave SPI) */
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Select the card and wait for ready                                    */
+/*-----------------------------------------------------------------------*/
+
+static
+int select (void)	/* 1:Successful, 0:Timeout */
+{
+	CS_LOW();
+	rcvr_spi();	/* Dummy clock (force DO enabled) */
+
+	if (wait_ready()) return 1;	/* OK */
+	deselect();
+	return 0;	/* Timeout */
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Power Control  (Platform dependent)                                   */
+/*-----------------------------------------------------------------------*/
+/* When the target system does not support socket power control, there   */
+/* is nothing to do in these functions and chk_power always returns 1.   */
+
+static
+int power_status(void)		/* Socket power state: 0=off, 1=on */
+{
+    return 0;
+    // matt
+	//return (PORTE & 0x80) ? 0 : 1;
+}
+
+
+static
+void power_on (void)
+{
+    // matt
+#if 0
+	PORTE &= ~0x80;				/* Socket power on */
+	for (Timer1 = 2; Timer1; );	/* Wait for 20ms */
+	PORTB = 0b10110101;			/* Enable drivers */
+	DDRB  = 0b11000111;
+#endif
+
+	SPCR = 0x52;			/* Enable SPI function in mode 0 */
+	SPSR = 0x01;			/* SPI 2x mode */
+}
+
+
+static
+void power_off (void)
+{
+	SPCR = 0;				/* Disable SPI function */
+	DDRB  = 0b11000000;		/* Disable drivers */
+	PORTB = 0b10110000;
+
+    // matt
+#if 0
+	PORTE |=  0x80;			/* Socket power off */
+#endif
+	Stat |= STA_NOINIT;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Receive a data packet from MMC                                        */
+/*-----------------------------------------------------------------------*/
+
+static
+int rcvr_datablock (
+	BYTE *buff,			/* Data buffer to store received data */
+	UINT btr			/* Byte count (must be multiple of 4) */
+)
+{
+	BYTE token;
+
+
+	Timer1 = 20;
+	do {							/* Wait for data packet in timeout of 200ms */
+		token = rcvr_spi();
+	} while ((token == 0xFF) && Timer1);
+	if(token != 0xFE) return 0;		/* If not valid data token, retutn with error */
+
+	do {							/* Receive the data block into buffer */
+		rcvr_spi_m(buff++);
+		rcvr_spi_m(buff++);
+		rcvr_spi_m(buff++);
+		rcvr_spi_m(buff++);
+	} while (btr -= 4);
+	rcvr_spi();						/* Discard CRC */
+	rcvr_spi();
+
+	return 1;						/* Return with success */
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Send a data packet to MMC                                             */
+/*-----------------------------------------------------------------------*/
+
+static
+int xmit_datablock (
+	const BYTE *buff,	/* 512 byte data block to be transmitted */
+	BYTE token			/* Data/Stop token */
+)
+{
+	BYTE resp, wc;
+
+
+	if (!wait_ready()) return 0;
+
+	xmit_spi(token);					/* Xmit data token */
+	if (token != 0xFD) {	/* Is data token */
+		wc = 0;
+		do {							/* Xmit the 512 byte data block to MMC */
+			xmit_spi(*buff++);
+			xmit_spi(*buff++);
+		} while (--wc);
+		xmit_spi(0xFF);					/* CRC (Dummy) */
+		xmit_spi(0xFF);
+		resp = rcvr_spi();				/* Reveive data response */
+		if ((resp & 0x1F) != 0x05)		/* If not accepted, return with error */
+			return 0;
+	}
+
+	return 1;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Send a command packet to MMC                                          */
+/*-----------------------------------------------------------------------*/
+
+static
+BYTE send_cmd (		/* Returns R1 resp (bit7==1:Send failed) */
+	BYTE cmd,		/* Command index */
+	DWORD arg		/* Argument */
+)
+{
+	BYTE n, res;
+
+
+	if (cmd & 0x80) {	/* ACMD<n> is the command sequense of CMD55-CMD<n> */
+		cmd &= 0x7F;
+		res = send_cmd(CMD55, 0);
+		if (res > 1) return res;
+	}
+
+	/* Select the card and wait for ready */
+	deselect();
+	if (!select()) return 0xFF;
+
+	/* Send command packet */
+	xmit_spi(0x40 | cmd);				/* Start + Command index */
+	xmit_spi((BYTE)(arg >> 24));		/* Argument[31..24] */
+	xmit_spi((BYTE)(arg >> 16));		/* Argument[23..16] */
+	xmit_spi((BYTE)(arg >> 8));			/* Argument[15..8] */
+	xmit_spi((BYTE)arg);				/* Argument[7..0] */
+	n = 0x01;							/* Dummy CRC + Stop */
+	if (cmd == CMD0) n = 0x95;			/* Valid CRC for CMD0(0) */
+	if (cmd == CMD8) n = 0x87;			/* Valid CRC for CMD8(0x1AA) */
+	xmit_spi(n);
+
+	/* Receive command response */
+	if (cmd == CMD12) rcvr_spi();		/* Skip a stuff byte when stop reading */
+	n = 10;								/* Wait for a valid response in timeout of 10 attempts */
+	do
+		res = rcvr_spi();
+	while ((res & 0x80) && --n);
+
+	return res;			/* Return with the response value */
+}
+
+
+
+/*--------------------------------------------------------------------------
+
+   Public Functions
+
+---------------------------------------------------------------------------*/
+
+
+/*-----------------------------------------------------------------------*/
+/* Initialize Disk Drive                                                 */
+/*-----------------------------------------------------------------------*/
+
+DSTATUS disk_initialize (
+	BYTE drv		/* Physical drive nmuber (0) */
+)
+{
+	BYTE n, cmd, ty, ocr[4];
+
+
+	if (drv) return STA_NOINIT;			/* Supports only single drive */
+	if (Stat & STA_NODISK) return Stat;	/* No card in the socket */
+
+	power_on();							/* Force socket power on */
+	FCLK_SLOW();
+	for (n = 10; n; n--) rcvr_spi();	/* 80 dummy clocks */
+
+	ty = 0;
+	if (send_cmd(CMD0, 0) == 1) {			/* Enter Idle state */
+		Timer1 = 100;						/* Initialization timeout of 1000 msec */
+		if (send_cmd(CMD8, 0x1AA) == 1) {	/* SDv2? */
+			for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();		/* Get trailing return value of R7 resp */
+			if (ocr[2] == 0x01 && ocr[3] == 0xAA) {				/* The card can work at vdd range of 2.7-3.6V */
+				while (Timer1 && send_cmd(ACMD41, 1UL << 30));	/* Wait for leaving idle state (ACMD41 with HCS bit) */
+				if (Timer1 && send_cmd(CMD58, 0) == 0) {		/* Check CCS bit in the OCR */
+					for (n = 0; n < 4; n++) ocr[n] = rcvr_spi();
+					ty = (ocr[0] & 0x40) ? CT_SD2 | CT_BLOCK : CT_SD2;	/* SDv2 */
+				}
+			}
+		} else {							/* SDv1 or MMCv3 */
+			if (send_cmd(ACMD41, 0) <= 1) 	{
+				ty = CT_SD1; cmd = ACMD41;	/* SDv1 */
+			} else {
+				ty = CT_MMC; cmd = CMD1;	/* MMCv3 */
+			}
+			while (Timer1 && send_cmd(cmd, 0));			/* Wait for leaving idle state */
+			if (!Timer1 || send_cmd(CMD16, 512) != 0)	/* Set R/W block length to 512 */
+				ty = 0;
+		}
+	}
+	CardType = ty;
+	deselect();
+
+	if (ty) {			/* Initialization succeded */
+		Stat &= ~STA_NOINIT;		/* Clear STA_NOINIT */
+		FCLK_FAST();
+	} else {			/* Initialization failed */
+		power_off();
+	}
+
+	return Stat;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Get Disk Status                                                       */
+/*-----------------------------------------------------------------------*/
+
+DSTATUS disk_status (
+	BYTE drv		/* Physical drive nmuber (0) */
+)
+{
+	if (drv) return STA_NOINIT;		/* Supports only single drive */
+	return Stat;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Read Sector(s)                                                        */
+/*-----------------------------------------------------------------------*/
+
+DRESULT disk_read (
+	BYTE drv,			/* Physical drive nmuber (0) */
+	BYTE *buff,			/* Pointer to the data buffer to store read data */
+	DWORD sector,		/* Start sector number (LBA) */
+	BYTE count			/* Sector count (1..255) */
+)
+{
+	if (drv || !count) return RES_PARERR;
+	if (Stat & STA_NOINIT) return RES_NOTRDY;
+
+	if (!(CardType & CT_BLOCK)) sector *= 512;	/* Convert to byte address if needed */
+
+	if (count == 1) {	/* Single block read */
+		if ((send_cmd(CMD17, sector) == 0)	/* READ_SINGLE_BLOCK */
+			&& rcvr_datablock(buff, 512))
+			count = 0;
+	}
+	else {				/* Multiple block read */
+		if (send_cmd(CMD18, sector) == 0) {	/* READ_MULTIPLE_BLOCK */
+			do {
+				if (!rcvr_datablock(buff, 512)) break;
+				buff += 512;
+			} while (--count);
+			send_cmd(CMD12, 0);				/* STOP_TRANSMISSION */
+		}
+	}
+	deselect();
+
+	return count ? RES_ERROR : RES_OK;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Write Sector(s)                                                       */
+/*-----------------------------------------------------------------------*/
+
+DRESULT disk_write (
+	BYTE drv,			/* Physical drive nmuber (0) */
+	const BYTE *buff,	/* Pointer to the data to be written */
+	DWORD sector,		/* Start sector number (LBA) */
+	BYTE count			/* Sector count (1..255) */
+)
+{
+	if (drv || !count) return RES_PARERR;
+	if (Stat & STA_NOINIT) return RES_NOTRDY;
+	if (Stat & STA_PROTECT) return RES_WRPRT;
+
+	if (!(CardType & CT_BLOCK)) sector *= 512;	/* Convert to byte address if needed */
+
+	if (count == 1) {	/* Single block write */
+		if ((send_cmd(CMD24, sector) == 0)	/* WRITE_BLOCK */
+			&& xmit_datablock(buff, 0xFE))
+			count = 0;
+	}
+	else {				/* Multiple block write */
+		if (CardType & CT_SDC) send_cmd(ACMD23, count);
+		if (send_cmd(CMD25, sector) == 0) {	/* WRITE_MULTIPLE_BLOCK */
+			do {
+				if (!xmit_datablock(buff, 0xFC)) break;
+				buff += 512;
+			} while (--count);
+			if (!xmit_datablock(0, 0xFD))	/* STOP_TRAN token */
+				count = 1;
+		}
+	}
+	deselect();
+
+	return count ? RES_ERROR : RES_OK;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Miscellaneous Functions                                               */
+/*-----------------------------------------------------------------------*/
+
+DRESULT disk_ioctl (
+	BYTE drv,		/* Physical drive nmuber (0) */
+	BYTE ctrl,		/* Control code */
+	void *buff		/* Buffer to send/receive control data */
+)
+{
+	DRESULT res;
+	BYTE n, csd[16], *ptr = buff;
+	WORD csize;
+
+
+	if (drv) return RES_PARERR;
+
+	res = RES_ERROR;
+
+	if (ctrl == CTRL_POWER) {
+		switch (ptr[0]) {
+		case 0:		/* Sub control code (POWER_OFF) */
+			power_off();		/* Power off */
+			res = RES_OK;
+			break;
+		case 1:		/* Sub control code (POWER_GET) */
+			ptr[1] = (BYTE)power_status();
+			res = RES_OK;
+			break;
+		default :
+			res = RES_PARERR;
+		}
+	}
+	else {
+		if (Stat & STA_NOINIT) return RES_NOTRDY;
+
+		switch (ctrl) {
+		case CTRL_SYNC :		/* Make sure that no pending write process. Do not remove this or written sector might not left updated. */
+			if (select()) {
+				deselect();
+				res = RES_OK;
+			}
+			break;
+
+		case GET_SECTOR_COUNT :	/* Get number of sectors on the disk (DWORD) */
+			if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) {
+				if ((csd[0] >> 6) == 1) {	/* SDC ver 2.00 */
+					csize = csd[9] + ((WORD)csd[8] << 8) + 1;
+					*(DWORD*)buff = (DWORD)csize << 10;
+				} else {					/* SDC ver 1.XX or MMC*/
+					n = (csd[5] & 15) + ((csd[10] & 128) >> 7) + ((csd[9] & 3) << 1) + 2;
+					csize = (csd[8] >> 6) + ((WORD)csd[7] << 2) + ((WORD)(csd[6] & 3) << 10) + 1;
+					*(DWORD*)buff = (DWORD)csize << (n - 9);
+				}
+				res = RES_OK;
+			}
+			break;
+
+		case GET_SECTOR_SIZE :	/* Get R/W sector size (WORD) */
+			*(WORD*)buff = 512;
+			res = RES_OK;
+			break;
+
+		case GET_BLOCK_SIZE :	/* Get erase block size in unit of sector (DWORD) */
+			if (CardType & CT_SD2) {	/* SDv2? */
+				if (send_cmd(ACMD13, 0) == 0) {	/* Read SD status */
+					rcvr_spi();
+					if (rcvr_datablock(csd, 16)) {				/* Read partial block */
+						for (n = 64 - 16; n; n--) rcvr_spi();	/* Purge trailing data */
+						*(DWORD*)buff = 16UL << (csd[10] >> 4);
+						res = RES_OK;
+					}
+				}
+			} else {					/* SDv1 or MMCv3 */
+				if ((send_cmd(CMD9, 0) == 0) && rcvr_datablock(csd, 16)) {	/* Read CSD */
+					if (CardType & CT_SD1) {	/* SDv1 */
+						*(DWORD*)buff = (((csd[10] & 63) << 1) + ((WORD)(csd[11] & 128) >> 7) + 1) << ((csd[13] >> 6) - 1);
+					} else {					/* MMCv3 */
+						*(DWORD*)buff = ((WORD)((csd[10] & 124) >> 2) + 1) * (((csd[11] & 3) << 3) + ((csd[11] & 224) >> 5) + 1);
+					}
+					res = RES_OK;
+				}
+			}
+			break;
+
+		case MMC_GET_TYPE :		/* Get card type flags (1 byte) */
+			*ptr = CardType;
+			res = RES_OK;
+			break;
+
+		case MMC_GET_CSD :		/* Receive CSD as a data block (16 bytes) */
+			if (send_cmd(CMD9, 0) == 0		/* READ_CSD */
+				&& rcvr_datablock(ptr, 16))
+				res = RES_OK;
+			break;
+
+		case MMC_GET_CID :		/* Receive CID as a data block (16 bytes) */
+			if (send_cmd(CMD10, 0) == 0		/* READ_CID */
+				&& rcvr_datablock(ptr, 16))
+				res = RES_OK;
+			break;
+
+		case MMC_GET_OCR :		/* Receive OCR as an R3 resp (4 bytes) */
+			if (send_cmd(CMD58, 0) == 0) {	/* READ_OCR */
+				for (n = 4; n; n--) *ptr++ = rcvr_spi();
+				res = RES_OK;
+			}
+			break;
+
+		case MMC_GET_SDSTAT :	/* Receive SD statsu as a data block (64 bytes) */
+			if (send_cmd(ACMD13, 0) == 0) {	/* SD_STATUS */
+				rcvr_spi();
+				if (rcvr_datablock(ptr, 64))
+					res = RES_OK;
+			}
+			break;
+
+		default:
+			res = RES_PARERR;
+		}
+
+		deselect();
+	}
+
+	return res;
+}
+
+
+
+/*-----------------------------------------------------------------------*/
+/* Device Timer Interrupt Procedure                                      */
+/*-----------------------------------------------------------------------*/
+/* This function must be called in period of 10ms                        */
+
+void disk_timerproc (void)
+{
+	BYTE n, s;
+
+
+	n = Timer1;				/* 100Hz decrement timer */
+	if (n) Timer1 = --n;
+	n = Timer2;
+	if (n) Timer2 = --n;
+
+	s = Stat;
+
+	if (SOCKWP)				/* Write protected */
+		s |= STA_PROTECT;
+	else					/* Write enabled */
+		s &= ~STA_PROTECT;
+
+	if (SOCKINS)			/* Card inserted */
+		s &= ~STA_NODISK;
+	else					/* Socket empty */
+		s |= (STA_NODISK | STA_NOINIT);
+
+	Stat = s;				/* Update MMC status */
+}