mtd: nand: Add driver for Ricoh xD/SmartMedia reader

This adds a driver for Ricoh R5C852 xD card reader.

This reader is a part of larger mulifunction chip
and found at least in R5C832

Driver is complete, but bewere of the fact that some
(probably only type M) xD cards are 'fake' which means that
they have an on board CPU and expose emulated nand command set

These cards don't even store the  oob area on the flash,
but generate it on the fly from something else.

Thus they demand to have proper values written in the oob area,
and therefore only useful with SmartMedia FTL.
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

MAINTAINERS

@@ -4567,6 +4567,12 @@ S:	Maintained
 F:	Documentation/rfkill.txt
 F:	net/rfkill/
 
+RICOH SMARTMEDIA/XD DRIVER
+M:	Maxim Levitsky <maximlevitsky@gmail.com>
+S:	Maintained
+F:	drivers/mtd/nand/r822.c
+F:	drivers/mtd/nand/r822.h
+
 RISCOM8 DRIVER
 S:	Orphan
 F:	Documentation/serial/riscom8.txt

drivers/mtd/nand/Kconfig

@@ -102,6 +102,17 @@ config MTD_NAND_OMAP_PREFETCH_DMA
 config MTD_NAND_IDS
 	tristate
 
+config MTD_NAND_RICOH
+	tristate "Ricoh xD card reader"
+	default n
+	select MTD_SM_COMMON
+	help
+	  Enable support for Ricoh R5C852 xD card reader
+	  You also need to enable ether
+	  NAND SSFDC (SmartMedia) read only translation layer' or new
+	  expermental, readwrite
+	  'SmartMedia/xD new translation layer'
+
 config MTD_NAND_AU1550
 	tristate "Au1550/1200 NAND support"
 	depends on SOC_AU1200 || SOC_AU1550

drivers/mtd/nand/Makefile

@@ -43,5 +43,6 @@ obj-$(CONFIG_MTD_NAND_NUC900)		+= nuc900_nand.o
 obj-$(CONFIG_MTD_NAND_NOMADIK)		+= nomadik_nand.o
 obj-$(CONFIG_MTD_NAND_BCM_UMI)		+= bcm_umi_nand.o nand_bcm_umi.o
 obj-$(CONFIG_MTD_NAND_MPC5121_NFC)	+= mpc5121_nfc.o
+obj-$(CONFIG_MTD_NAND_RICOH)		+= r852.o
 
 nand-objs := nand_base.o nand_bbt.o

drivers/mtd/nand/r852.h

+/*
+ * Copyright © 2009 - Maxim Levitsky
+ * driver for Ricoh xD readers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/pci.h>
+#include <linux/completion.h>
+#include <linux/workqueue.h>
+#include <linux/mtd/nand.h>
+#include <linux/spinlock.h>
+
+
+/* nand interface + ecc
+   byte write/read does one cycle on nand data lines.
+   dword write/read does 4 cycles
+   if R852_CTL_ECC_ACCESS is set in R852_CTL, then dword read reads
+   results of ecc correction, if DMA read was done before.
+   If write was done two dword reads read generated ecc checksums
+*/
+#define	R852_DATALINE		0x00
+
+/* control register */
+#define R852_CTL		0x04
+#define R852_CTL_COMMAND 	0x01	/* send command (#CLE)*/
+#define R852_CTL_DATA		0x02	/* read/write data (#ALE)*/
+#define R852_CTL_ON		0x04	/* only seem to controls the hd led, */
+					/* but has to be set on start...*/
+#define R852_CTL_RESET		0x08	/* unknown, set only on start once*/
+#define R852_CTL_CARDENABLE	0x10	/* probably (#CE) - always set*/
+#define R852_CTL_ECC_ENABLE	0x20	/* enable ecc engine */
+#define R852_CTL_ECC_ACCESS	0x40	/* read/write ecc via reg #0*/
+#define R852_CTL_WRITE		0x80	/* set when performing writes (#WP) */
+
+/* card detection status */
+#define R852_CARD_STA		0x05
+
+#define R852_CARD_STA_CD	0x01	/* state of #CD line, same as 0x04 */
+#define R852_CARD_STA_RO	0x02	/* card is readonly */
+#define R852_CARD_STA_PRESENT	0x04	/* card is present (#CD) */
+#define R852_CARD_STA_ABSENT	0x08	/* card is absent */
+#define R852_CARD_STA_BUSY	0x80	/* card is busy - (#R/B) */
+
+/* card detection irq status & enable*/
+#define R852_CARD_IRQ_STA	0x06	/* IRQ status */
+#define R852_CARD_IRQ_ENABLE	0x07	/* IRQ enable */
+
+#define R852_CARD_IRQ_CD	0x01	/* fire when #CD lights, same as 0x04*/
+#define R852_CARD_IRQ_REMOVE	0x04	/* detect card removal */
+#define R852_CARD_IRQ_INSERT	0x08	/* detect card insert */
+#define R852_CARD_IRQ_UNK1	0x10	/* unknown */
+#define R852_CARD_IRQ_GENABLE	0x80	/* general enable */
+#define R852_CARD_IRQ_MASK	0x1D
+
+
+
+/* hardware enable */
+#define R852_HW			0x08
+#define R852_HW_ENABLED		0x01	/* hw enabled */
+#define R852_HW_UNKNOWN		0x80
+
+
+/* dma capabilities */
+#define R852_DMA_CAP		0x09
+#define R852_SMBIT		0x20	/* if set with bit #6 or bit #7, then */
+					/* hw is smartmedia */
+#define R852_DMA1		0x40	/* if set w/bit #7, dma is supported */
+#define R852_DMA2		0x80	/* if set w/bit #6, dma is supported */
+
+
+/* physical DMA address - 32 bit value*/
+#define R852_DMA_ADDR		0x0C
+
+
+/* dma settings */
+#define R852_DMA_SETTINGS	0x10
+#define R852_DMA_MEMORY		0x01	/* (memory <-> internal hw buffer) */
+#define R852_DMA_READ		0x02	/* 0 = write, 1 = read */
+#define R852_DMA_INTERNAL	0x04	/* (internal hw buffer <-> card) */
+
+/* dma IRQ status */
+#define R852_DMA_IRQ_STA		0x14
+
+/* dma IRQ enable */
+#define R852_DMA_IRQ_ENABLE	0x18
+
+#define R852_DMA_IRQ_MEMORY	0x01	/* (memory <-> internal hw buffer) */
+#define R852_DMA_IRQ_ERROR	0x02	/* error did happen */
+#define R852_DMA_IRQ_INTERNAL	0x04	/* (internal hw buffer <-> card) */
+#define R852_DMA_IRQ_MASK	0x07	/* mask of all IRQ bits */
+
+
+/* ECC syndrome format - read from reg #0 will return two copies of these for
+   each half of the page.
+   first byte is error byte location, and second, bit location + flags */
+#define R852_ECC_ERR_BIT_MSK	0x07	/* error bit location */
+#define R852_ECC_CORRECT		0x10	/* no errors - (guessed) */
+#define R852_ECC_CORRECTABLE	0x20	/* correctable error exist */
+#define R852_ECC_FAIL		0x40	/* non correctable error detected */
+
+#define R852_DMA_LEN		512
+
+#define DMA_INTERNAL	0
+#define DMA_MEMORY	1
+
+struct r852_device {
+	void __iomem *mmio;		/* mmio */
+	struct mtd_info *mtd;		/* mtd backpointer */
+	struct nand_chip *chip;		/* nand chip backpointer */
+	struct pci_dev *pci_dev;	/* pci backpointer */
+
+	/* dma area */
+	dma_addr_t phys_dma_addr;	/* bus address of buffer*/
+	struct completion dma_done;	/* data transfer done */
+
+	dma_addr_t phys_bounce_buffer;	/* bus address of bounce buffer */
+	uint8_t *bounce_buffer;		/* virtual address of bounce buffer */
+
+	int dma_dir;			/* 1 = read, 0 = write */
+	int dma_stage;			/* 0 - idle, 1 - first step,
+					   2 - second step */
+
+	int dma_state;			/* 0 = internal, 1 = memory */
+	int dma_error;			/* dma errors */
+	int dma_usable;			/* is it possible to use dma */
+
+	/* card status area */
+	struct delayed_work card_detect_work;
+	struct workqueue_struct *card_workqueue;
+	int card_registred;		/* card registered with mtd */
+	int card_detected;		/* card detected in slot */
+	int card_unstable;		/* whenever the card is inserted,
+					   is not known yet */
+	int readonly;			/* card is readonly */
+	int sm;				/* Is card smartmedia */
+
+	/* interrupt handling */
+	spinlock_t irqlock;		/* IRQ protecting lock */
+	int irq;			/* irq num */
+	int insuspend;			/* device is suspended */
+
+	/* misc */
+	void *tmp_buffer;		/* temporary buffer */
+	uint8_t ctlreg;			/* cached contents of control reg */
+};
+
+#define DRV_NAME "r852"
+
+
+#define dbg(format, ...) \
+	if (debug) \
+		printk(KERN_DEBUG DRV_NAME ": " format "\n", ## __VA_ARGS__)
+
+#define dbg_verbose(format, ...) \
+	if (debug > 1) \
+		printk(KERN_DEBUG DRV_NAME ": " format "\n", ## __VA_ARGS__)
+
+
+#define message(format, ...) \
+	printk(KERN_INFO DRV_NAME ": " format "\n", ## __VA_ARGS__)