mtd: rawnand: tango: Remove the driver

The tango platform is getting removed [1], so the driver is no
longer needed.

[1] https://lore.kernel.org/linux-arm-kernel/20210120124812.2800027-1-arnd@kernel.org/T/

Cc: Marc Gonzalez <marc.w.gonzalez@free.fr>
Cc: Mans Rullgard <mans@mansr.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20210120150555.1610132-1-arnd@kernel.org

3 files changed, 0 insertions, 735 deletions

diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
index 442a039b92f3..06f11cb73bf9 100644
--- a/drivers/mtd/nand/raw/Kconfig
+++ b/drivers/mtd/nand/raw/Kconfig
@@ -102,13 +102,6 @@ config MTD_NAND_S3C2410_CLKSTOP
 	  when the is NAND chip selected or released, but will save
 	  approximately 5mA of power when there is nothing happening.
 
-config MTD_NAND_TANGO
-	tristate "Tango NAND controller"
-	depends on ARCH_TANGO || COMPILE_TEST
-	depends on HAS_IOMEM
-	help
-	  Enables the NAND Flash controller on Tango chips.
-
 config MTD_NAND_SHARPSL
 	tristate "Sharp SL Series (C7xx + others) NAND controller"
 	depends on ARCH_PXA || COMPILE_TEST
diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile
index 32475a28d8f8..d011c6c53f8f 100644
--- a/drivers/mtd/nand/raw/Makefile
+++ b/drivers/mtd/nand/raw/Makefile
@@ -10,7 +10,6 @@ obj-$(CONFIG_MTD_NAND_DENALI_PCI)	+= denali_pci.o
 obj-$(CONFIG_MTD_NAND_DENALI_DT)	+= denali_dt.o
 obj-$(CONFIG_MTD_NAND_AU1550)		+= au1550nd.o
 obj-$(CONFIG_MTD_NAND_S3C2410)		+= s3c2410.o
-obj-$(CONFIG_MTD_NAND_TANGO)		+= tango_nand.o
 obj-$(CONFIG_MTD_NAND_DAVINCI)		+= davinci_nand.o
 obj-$(CONFIG_MTD_NAND_DISKONCHIP)	+= diskonchip.o
 obj-$(CONFIG_MTD_NAND_FSMC)		+= fsmc_nand.o
diff --git a/drivers/mtd/nand/raw/tango_nand.c b/drivers/mtd/nand/raw/tango_nand.c
deleted file mode 100644
index 359187b5a4be..000000000000
--- a/drivers/mtd/nand/raw/tango_nand.c
+++ /dev/null
@@ -1,727 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2016 Sigma Designs
- */
-
-#include <linux/io.h>
-#include <linux/of.h>
-#include <linux/clk.h>
-#include <linux/iopoll.h>
-#include <linux/module.h>
-#include <linux/mtd/rawnand.h>
-#include <linux/dmaengine.h>
-#include <linux/dma-mapping.h>
-#include <linux/platform_device.h>
-
-/* Offsets relative to chip->base */
-#define PBUS_CMD	0
-#define PBUS_ADDR	4
-#define PBUS_DATA	8
-
-/* Offsets relative to reg_base */
-#define NFC_STATUS	0x00
-#define NFC_FLASH_CMD	0x04
-#define NFC_DEVICE_CFG	0x08
-#define NFC_TIMING1	0x0c
-#define NFC_TIMING2	0x10
-#define NFC_XFER_CFG	0x14
-#define NFC_PKT_0_CFG	0x18
-#define NFC_PKT_N_CFG	0x1c
-#define NFC_BB_CFG	0x20
-#define NFC_ADDR_PAGE	0x24
-#define NFC_ADDR_OFFSET	0x28
-#define NFC_XFER_STATUS	0x2c
-
-/* NFC_STATUS values */
-#define CMD_READY	BIT(31)
-
-/* NFC_FLASH_CMD values */
-#define NFC_READ	1
-#define NFC_WRITE	2
-
-/* NFC_XFER_STATUS values */
-#define PAGE_IS_EMPTY	BIT(16)
-
-/* Offsets relative to mem_base */
-#define METADATA	0x000
-#define ERROR_REPORT	0x1c0
-
-/*
- * Error reports are split in two bytes:
- * byte 0 for the first packet in the page (PKT_0)
- * byte 1 for other packets in the page (PKT_N, for N > 0)
- * ERR_COUNT_PKT_N is the max error count over all but the first packet.
- */
-#define ERR_COUNT_PKT_0(v)	(((v) >> 0) & 0x3f)
-#define ERR_COUNT_PKT_N(v)	(((v) >> 8) & 0x3f)
-#define DECODE_FAIL_PKT_0(v)	(((v) & BIT(7)) == 0)
-#define DECODE_FAIL_PKT_N(v)	(((v) & BIT(15)) == 0)
-
-/* Offsets relative to pbus_base */
-#define PBUS_CS_CTRL	0x83c
-#define PBUS_PAD_MODE	0x8f0
-
-/* PBUS_CS_CTRL values */
-#define PBUS_IORDY	BIT(31)
-
-/*
- * PBUS_PAD_MODE values
- * In raw mode, the driver communicates directly with the NAND chips.
- * In NFC mode, the NAND Flash controller manages the communication.
- * We use NFC mode for read and write; raw mode for everything else.
- */
-#define MODE_RAW	0
-#define MODE_NFC	BIT(31)
-
-#define METADATA_SIZE	4
-#define BBM_SIZE	6
-#define FIELD_ORDER	15
-
-#define MAX_CS		4
-
-struct tango_nfc {
-	struct nand_controller hw;
-	void __iomem *reg_base;
-	void __iomem *mem_base;
-	void __iomem *pbus_base;
-	struct tango_chip *chips[MAX_CS];
-	struct dma_chan *chan;
-	int freq_kHz;
-};
-
-#define to_tango_nfc(ptr) container_of(ptr, struct tango_nfc, hw)
-
-struct tango_chip {
-	struct nand_chip nand_chip;
-	void __iomem *base;
-	u32 timing1;
-	u32 timing2;
-	u32 xfer_cfg;
-	u32 pkt_0_cfg;
-	u32 pkt_n_cfg;
-	u32 bb_cfg;
-};
-
-#define to_tango_chip(ptr) container_of(ptr, struct tango_chip, nand_chip)
-
-#define XFER_CFG(cs, page_count, steps, metadata_size)	\
-	((cs) << 24 | (page_count) << 16 | (steps) << 8 | (metadata_size))
-
-#define PKT_CFG(size, strength) ((size) << 16 | (strength))
-
-#define BB_CFG(bb_offset, bb_size) ((bb_offset) << 16 | (bb_size))
-
-#define TIMING(t0, t1, t2, t3) ((t0) << 24 | (t1) << 16 | (t2) << 8 | (t3))
-
-static void tango_select_target(struct nand_chip *chip, unsigned int cs)
-{
-	struct tango_nfc *nfc = to_tango_nfc(chip->controller);
-	struct tango_chip *tchip = to_tango_chip(chip);
-
-	writel_relaxed(tchip->timing1, nfc->reg_base + NFC_TIMING1);
-	writel_relaxed(tchip->timing2, nfc->reg_base + NFC_TIMING2);
-	writel_relaxed(tchip->xfer_cfg, nfc->reg_base + NFC_XFER_CFG);
-	writel_relaxed(tchip->pkt_0_cfg, nfc->reg_base + NFC_PKT_0_CFG);
-	writel_relaxed(tchip->pkt_n_cfg, nfc->reg_base + NFC_PKT_N_CFG);
-	writel_relaxed(tchip->bb_cfg, nfc->reg_base + NFC_BB_CFG);
-}
-
-static int tango_waitrdy(struct nand_chip *chip, unsigned int timeout_ms)
-{
-	struct tango_nfc *nfc = to_tango_nfc(chip->controller);
-	u32 status;
-
-	return readl_relaxed_poll_timeout(nfc->pbus_base + PBUS_CS_CTRL,
-					  status, status & PBUS_IORDY, 20,
-					  timeout_ms);
-}
-
-static int tango_exec_instr(struct nand_chip *chip,
-			    const struct nand_op_instr *instr)
-{
-	struct tango_chip *tchip = to_tango_chip(chip);
-	unsigned int i;
-
-	switch (instr->type) {
-	case NAND_OP_CMD_INSTR:
-		writeb_relaxed(instr->ctx.cmd.opcode, tchip->base + PBUS_CMD);
-		return 0;
-	case NAND_OP_ADDR_INSTR:
-		for (i = 0; i < instr->ctx.addr.naddrs; i++)
-			writeb_relaxed(instr->ctx.addr.addrs[i],
-				       tchip->base + PBUS_ADDR);
-		return 0;
-	case NAND_OP_DATA_IN_INSTR:
-		ioread8_rep(tchip->base + PBUS_DATA, instr->ctx.data.buf.in,
-			    instr->ctx.data.len);
-		return 0;
-	case NAND_OP_DATA_OUT_INSTR:
-		iowrite8_rep(tchip->base + PBUS_DATA, instr->ctx.data.buf.out,
-			     instr->ctx.data.len);
-		return 0;
-	case NAND_OP_WAITRDY_INSTR:
-		return tango_waitrdy(chip,
-				     instr->ctx.waitrdy.timeout_ms);
-	default:
-		break;
-	}
-
-	return -EINVAL;
-}
-
-static int tango_exec_op(struct nand_chip *chip,
-			 const struct nand_operation *op,
-			 bool check_only)
-{
-	unsigned int i;
-	int ret = 0;
-
-	if (check_only)
-		return 0;
-
-	tango_select_target(chip, op->cs);
-	for (i = 0; i < op->ninstrs; i++) {
-		ret = tango_exec_instr(chip, &op->instrs[i]);
-		if (ret)
-			break;
-	}
-
-	return ret;
-}
-
-/*
- * The controller does not check for bitflips in erased pages,
- * therefore software must check instead.
- */
-static int check_erased_page(struct nand_chip *chip, u8 *buf)
-{
-	struct mtd_info *mtd = nand_to_mtd(chip);
-	u8 *meta = chip->oob_poi + BBM_SIZE;
-	u8 *ecc = chip->oob_poi + BBM_SIZE + METADATA_SIZE;
-	const int ecc_size = chip->ecc.bytes;
-	const int pkt_size = chip->ecc.size;
-	int i, res, meta_len, bitflips = 0;
-
-	for (i = 0; i < chip->ecc.steps; ++i) {
-		meta_len = i ? 0 : METADATA_SIZE;
-		res = nand_check_erased_ecc_chunk(buf, pkt_size, ecc, ecc_size,
-						  meta, meta_len,
-						  chip->ecc.strength);
-		if (res < 0)
-			mtd->ecc_stats.failed++;
-		else
-			mtd->ecc_stats.corrected += res;
-
-		bitflips = max(res, bitflips);
-		buf += pkt_size;
-		ecc += ecc_size;
-	}
-
-	return bitflips;
-}
-
-static int decode_error_report(struct nand_chip *chip)
-{
-	u32 status, res;
-	struct mtd_info *mtd = nand_to_mtd(chip);
-	struct tango_nfc *nfc = to_tango_nfc(chip->controller);
-
-	status = readl_relaxed(nfc->reg_base + NFC_XFER_STATUS);
-	if (status & PAGE_IS_EMPTY)
-		return 0;
-
-	res = readl_relaxed(nfc->mem_base + ERROR_REPORT);
-
-	if (DECODE_FAIL_PKT_0(res) || DECODE_FAIL_PKT_N(res))
-		return -EBADMSG;
-
-	/* ERR_COUNT_PKT_N is max, not sum, but that's all we have */
-	mtd->ecc_stats.corrected +=
-		ERR_COUNT_PKT_0(res) + ERR_COUNT_PKT_N(res);
-
-	return max(ERR_COUNT_PKT_0(res), ERR_COUNT_PKT_N(res));
-}
-
-static void tango_dma_callback(void *arg)
-{
-	complete(arg);
-}
-
-static int do_dma(struct tango_nfc *nfc, enum dma_data_direction dir, int cmd,
-		  const void *buf, int len, int page)
-{
-	void __iomem *addr = nfc->reg_base + NFC_STATUS;
-	struct dma_chan *chan = nfc->chan;
-	struct dma_async_tx_descriptor *desc;
-	enum dma_transfer_direction tdir;
-	struct scatterlist sg;
-	struct completion tx_done;
-	int err = -EIO;
-	u32 res, val;
-
-	sg_init_one(&sg, buf, len);
-	if (dma_map_sg(chan->device->dev, &sg, 1, dir) != 1)
-		return -EIO;
-
-	tdir = dir == DMA_TO_DEVICE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
-	desc = dmaengine_prep_slave_sg(chan, &sg, 1, tdir, DMA_PREP_INTERRUPT);
-	if (!desc)
-		goto dma_unmap;
-
-	desc->callback = tango_dma_callback;
-	desc->callback_param = &tx_done;
-	init_completion(&tx_done);
-
-	writel_relaxed(MODE_NFC, nfc->pbus_base + PBUS_PAD_MODE);
-
-	writel_relaxed(page, nfc->reg_base + NFC_ADDR_PAGE);
-	writel_relaxed(0, nfc->reg_base + NFC_ADDR_OFFSET);
-	writel_relaxed(cmd, nfc->reg_base + NFC_FLASH_CMD);
-
-	dmaengine_submit(desc);
-	dma_async_issue_pending(chan);
-
-	res = wait_for_completion_timeout(&tx_done, HZ);
-	if (res > 0)
-		err = readl_poll_timeout(addr, val, val & CMD_READY, 0, 1000);
-
-	writel_relaxed(MODE_RAW, nfc->pbus_base + PBUS_PAD_MODE);
-
-dma_unmap:
-	dma_unmap_sg(chan->device->dev, &sg, 1, dir);
-
-	return err;
-}
-
-static int tango_read_page(struct nand_chip *chip, u8 *buf,
-			   int oob_required, int page)
-{
-	struct mtd_info *mtd = nand_to_mtd(chip);
-	struct tango_nfc *nfc = to_tango_nfc(chip->controller);
-	int err, res, len = mtd->writesize;
-
-	tango_select_target(chip, chip->cur_cs);
-	if (oob_required)
-		chip->ecc.read_oob(chip, page);
-
-	err = do_dma(nfc, DMA_FROM_DEVICE, NFC_READ, buf, len, page);
-	if (err)
-		return err;
-
-	res = decode_error_report(chip);
-	if (res < 0) {
-		chip->ecc.read_oob_raw(chip, page);
-		res = check_erased_page(chip, buf);
-	}
-
-	return res;
-}
-
-static int tango_write_page(struct nand_chip *chip, const u8 *buf,
-			    int oob_required, int page)
-{
-	struct mtd_info *mtd = nand_to_mtd(chip);
-	struct tango_nfc *nfc = to_tango_nfc(chip->controller);
-	const struct nand_sdr_timings *timings;
-	int err, len = mtd->writesize;
-	u8 status;
-
-	/* Calling tango_write_oob() would send PAGEPROG twice */
-	if (oob_required)
-		return -ENOTSUPP;
-
-	tango_select_target(chip, chip->cur_cs);
-	writel_relaxed(0xffffffff, nfc->mem_base + METADATA);
-	err = do_dma(nfc, DMA_TO_DEVICE, NFC_WRITE, buf, len, page);
-	if (err)
-		return err;
-
-	timings = nand_get_sdr_timings(nand_get_interface_config(chip));
-	err = tango_waitrdy(chip, PSEC_TO_MSEC(timings->tR_max));
-	if (err)
-		return err;
-
-	err = nand_status_op(chip, &status);
-	if (err)
-		return err;
-
-	return (status & NAND_STATUS_FAIL) ? -EIO : 0;
-}
-
-static void aux_read(struct nand_chip *chip, u8 **buf, int len, int *pos)
-{
-	*pos += len;
-
-	if (!*buf) {
-		/* skip over "len" bytes */
-		nand_change_read_column_op(chip, *pos, NULL, 0, false);
-	} else {
-		struct tango_chip *tchip = to_tango_chip(chip);
-
-		ioread8_rep(tchip->base + PBUS_DATA, *buf, len);
-		*buf += len;
-	}
-}
-
-static void aux_write(struct nand_chip *chip, const u8 **buf, int len, int *pos)
-{
-	*pos += len;
-
-	if (!*buf) {
-		/* skip over "len" bytes */
-		nand_change_write_column_op(chip, *pos, NULL, 0, false);
-	} else {
-		struct tango_chip *tchip = to_tango_chip(chip);
-
-		iowrite8_rep(tchip->base + PBUS_DATA, *buf, len);
-		*buf += len;
-	}
-}
-
-/*
- * Physical page layout (not drawn to scale)
- *
- * NB: Bad Block Marker area splits PKT_N in two (N1, N2).
- *
- * +---+-----------------+-------+-----+-----------+-----+----+-------+
- * | M |      PKT_0      | ECC_0 | ... |     N1    | BBM | N2 | ECC_N |
- * +---+-----------------+-------+-----+-----------+-----+----+-------+
- *
- * Logical page layout:
- *
- *       +-----+---+-------+-----+-------+
- * oob = | BBM | M | ECC_0 | ... | ECC_N |
- *       +-----+---+-------+-----+-------+
- *
- *       +-----------------+-----+-----------------+
- * buf = |      PKT_0      | ... |      PKT_N      |
- *       +-----------------+-----+-----------------+
- */
-static void raw_read(struct nand_chip *chip, u8 *buf, u8 *oob)
-{
-	struct mtd_info *mtd = nand_to_mtd(chip);
-	u8 *oob_orig = oob;
-	const int page_size = mtd->writesize;
-	const int ecc_size = chip->ecc.bytes;
-	const int pkt_size = chip->ecc.size;
-	int pos = 0; /* position within physical page */
-	int rem = page_size; /* bytes remaining until BBM area */
-
-	if (oob)
-		oob += BBM_SIZE;
-
-	aux_read(chip, &oob, METADATA_SIZE, &pos);
-
-	while (rem > pkt_size) {
-		aux_read(chip, &buf, pkt_size, &pos);
-		aux_read(chip, &oob, ecc_size, &pos);
-		rem = page_size - pos;
-	}
-
-	aux_read(chip, &buf, rem, &pos);
-	aux_read(chip, &oob_orig, BBM_SIZE, &pos);
-	aux_read(chip, &buf, pkt_size - rem, &pos);
-	aux_read(chip, &oob, ecc_size, &pos);
-}
-
-static void raw_write(struct nand_chip *chip, const u8 *buf, const u8 *oob)
-{
-	struct mtd_info *mtd = nand_to_mtd(chip);
-	const u8 *oob_orig = oob;
-	const int page_size = mtd->writesize;
-	const int ecc_size = chip->ecc.bytes;
-	const int pkt_size = chip->ecc.size;
-	int pos = 0; /* position within physical page */
-	int rem = page_size; /* bytes remaining until BBM area */
-
-	if (oob)
-		oob += BBM_SIZE;
-
-	aux_write(chip, &oob, METADATA_SIZE, &pos);
-
-	while (rem > pkt_size) {
-		aux_write(chip, &buf, pkt_size, &pos);
-		aux_write(chip, &oob, ecc_size, &pos);
-		rem = page_size - pos;
-	}
-
-	aux_write(chip, &buf, rem, &pos);
-	aux_write(chip, &oob_orig, BBM_SIZE, &pos);
-	aux_write(chip, &buf, pkt_size - rem, &pos);
-	aux_write(chip, &oob, ecc_size, &pos);
-}
-
-static int tango_read_page_raw(struct nand_chip *chip, u8 *buf,
-			       int oob_required, int page)
-{
-	tango_select_target(chip, chip->cur_cs);
-	nand_read_page_op(chip, page, 0, NULL, 0);
-	raw_read(chip, buf, chip->oob_poi);
-	return 0;
-}
-
-static int tango_write_page_raw(struct nand_chip *chip, const u8 *buf,
-				int oob_required, int page)
-{
-	tango_select_target(chip, chip->cur_cs);
-	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
-	raw_write(chip, buf, chip->oob_poi);
-	return nand_prog_page_end_op(chip);
-}
-
-static int tango_read_oob(struct nand_chip *chip, int page)
-{
-	tango_select_target(chip, chip->cur_cs);
-	nand_read_page_op(chip, page, 0, NULL, 0);
-	raw_read(chip, NULL, chip->oob_poi);
-	return 0;
-}
-
-static int tango_write_oob(struct nand_chip *chip, int page)
-{
-	tango_select_target(chip, chip->cur_cs);
-	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
-	raw_write(chip, NULL, chip->oob_poi);
-	return nand_prog_page_end_op(chip);
-}
-
-static int oob_ecc(struct mtd_info *mtd, int idx, struct mtd_oob_region *res)
-{
-	struct nand_chip *chip = mtd_to_nand(mtd);
-	struct nand_ecc_ctrl *ecc = &chip->ecc;
-
-	if (idx >= ecc->steps)
-		return -ERANGE;
-
-	res->offset = BBM_SIZE + METADATA_SIZE + ecc->bytes * idx;
-	res->length = ecc->bytes;
-
-	return 0;
-}
-
-static int oob_free(struct mtd_info *mtd, int idx, struct mtd_oob_region *res)
-{
-	return -ERANGE; /* no free space in spare area */
-}
-
-static const struct mtd_ooblayout_ops tango_nand_ooblayout_ops = {
-	.ecc	= oob_ecc,
-	.free	= oob_free,
-};
-
-static u32 to_ticks(int kHz, int ps)
-{
-	return DIV_ROUND_UP_ULL((u64)kHz * ps, NSEC_PER_SEC);
-}
-
-static int tango_set_timings(struct nand_chip *chip, int csline,
-			     const struct nand_interface_config *conf)
-{
-	const struct nand_sdr_timings *sdr = nand_get_sdr_timings(conf);
-	struct tango_nfc *nfc = to_tango_nfc(chip->controller);
-	struct tango_chip *tchip = to_tango_chip(chip);
-	u32 Trdy, Textw, Twc, Twpw, Tacc, Thold, Trpw, Textr;
-	int kHz = nfc->freq_kHz;
-
-	if (IS_ERR(sdr))
-		return PTR_ERR(sdr);
-
-	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
-		return 0;
-
-	Trdy = to_ticks(kHz, sdr->tCEA_max - sdr->tREA_max);
-	Textw = to_ticks(kHz, sdr->tWB_max);
-	Twc = to_ticks(kHz, sdr->tWC_min);
-	Twpw = to_ticks(kHz, sdr->tWC_min - sdr->tWP_min);
-
-	Tacc = to_ticks(kHz, sdr->tREA_max);
-	Thold = to_ticks(kHz, sdr->tREH_min);
-	Trpw = to_ticks(kHz, sdr->tRC_min - sdr->tREH_min);
-	Textr = to_ticks(kHz, sdr->tRHZ_max);
-
-	tchip->timing1 = TIMING(Trdy, Textw, Twc, Twpw);
-	tchip->timing2 = TIMING(Tacc, Thold, Trpw, Textr);
-
-	return 0;
-}
-
-static int tango_attach_chip(struct nand_chip *chip)
-{
-	struct nand_ecc_ctrl *ecc = &chip->ecc;
-
-	ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
-	ecc->algo = NAND_ECC_ALGO_BCH;
-	ecc->bytes = DIV_ROUND_UP(ecc->strength * FIELD_ORDER, BITS_PER_BYTE);
-
-	ecc->read_page_raw = tango_read_page_raw;
-	ecc->write_page_raw = tango_write_page_raw;
-	ecc->read_page = tango_read_page;
-	ecc->write_page = tango_write_page;
-	ecc->read_oob = tango_read_oob;
-	ecc->write_oob = tango_write_oob;
-
-	return 0;
-}
-
-static const struct nand_controller_ops tango_controller_ops = {
-	.attach_chip = tango_attach_chip,
-	.setup_interface = tango_set_timings,
-	.exec_op = tango_exec_op,
-};
-
-static int chip_init(struct device *dev, struct device_node *np)
-{
-	u32 cs;
-	int err, res;
-	struct mtd_info *mtd;
-	struct nand_chip *chip;
-	struct tango_chip *tchip;
-	struct nand_ecc_ctrl *ecc;
-	struct tango_nfc *nfc = dev_get_drvdata(dev);
-
-	tchip = devm_kzalloc(dev, sizeof(*tchip), GFP_KERNEL);
-	if (!tchip)
-		return -ENOMEM;
-
-	res = of_property_count_u32_elems(np, "reg");
-	if (res < 0)
-		return res;
-
-	if (res != 1)
-		return -ENOTSUPP; /* Multi-CS chips are not supported */
-
-	err = of_property_read_u32_index(np, "reg", 0, &cs);
-	if (err)
-		return err;
-
-	if (cs >= MAX_CS)
-		return -EINVAL;
-
-	chip = &tchip->nand_chip;
-	ecc = &chip->ecc;
-	mtd = nand_to_mtd(chip);
-
-	chip->options = NAND_USES_DMA |
-			NAND_NO_SUBPAGE_WRITE |
-			NAND_WAIT_TCCS;
-	chip->controller = &nfc->hw;
-	tchip->base = nfc->pbus_base + (cs * 256);
-
-	nand_set_flash_node(chip, np);
-	mtd_set_ooblayout(mtd, &tango_nand_ooblayout_ops);
-	mtd->dev.parent = dev;
-
-	err = nand_scan(chip, 1);
-	if (err)
-		return err;
-
-	tchip->xfer_cfg = XFER_CFG(cs, 1, ecc->steps, METADATA_SIZE);
-	tchip->pkt_0_cfg = PKT_CFG(ecc->size + METADATA_SIZE, ecc->strength);
-	tchip->pkt_n_cfg = PKT_CFG(ecc->size, ecc->strength);
-	tchip->bb_cfg = BB_CFG(mtd->writesize, BBM_SIZE);
-
-	err = mtd_device_register(mtd, NULL, 0);
-	if (err) {
-		nand_cleanup(chip);
-		return err;
-	}
-
-	nfc->chips[cs] = tchip;
-
-	return 0;
-}
-
-static int tango_nand_remove(struct platform_device *pdev)
-{
-	struct tango_nfc *nfc = platform_get_drvdata(pdev);
-	struct nand_chip *chip;
-	int cs, ret;
-
-	dma_release_channel(nfc->chan);
-
-	for (cs = 0; cs < MAX_CS; ++cs) {
-		if (nfc->chips[cs]) {
-			chip = &nfc->chips[cs]->nand_chip;
-			ret = mtd_device_unregister(nand_to_mtd(chip));
-			WARN_ON(ret);
-			nand_cleanup(chip);
-		}
-	}
-
-	return 0;
-}
-
-static int tango_nand_probe(struct platform_device *pdev)
-{
-	int err;
-	struct clk *clk;
-	struct resource *res;
-	struct tango_nfc *nfc;
-	struct device_node *np;
-
-	nfc = devm_kzalloc(&pdev->dev, sizeof(*nfc), GFP_KERNEL);
-	if (!nfc)
-		return -ENOMEM;
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	nfc->reg_base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(nfc->reg_base))
-		return PTR_ERR(nfc->reg_base);
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
-	nfc->mem_base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(nfc->mem_base))
-		return PTR_ERR(nfc->mem_base);
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
-	nfc->pbus_base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(nfc->pbus_base))
-		return PTR_ERR(nfc->pbus_base);
-
-	writel_relaxed(MODE_RAW, nfc->pbus_base + PBUS_PAD_MODE);
-
-	clk = devm_clk_get(&pdev->dev, NULL);
-	if (IS_ERR(clk))
-		return PTR_ERR(clk);
-
-	nfc->chan = dma_request_chan(&pdev->dev, "rxtx");
-	if (IS_ERR(nfc->chan))
-		return PTR_ERR(nfc->chan);
-
-	platform_set_drvdata(pdev, nfc);
-	nand_controller_init(&nfc->hw);
-	nfc->hw.ops = &tango_controller_ops;
-	nfc->freq_kHz = clk_get_rate(clk) / 1000;
-
-	for_each_child_of_node(pdev->dev.of_node, np) {
-		err = chip_init(&pdev->dev, np);
-		if (err) {
-			tango_nand_remove(pdev);
-			of_node_put(np);
-			return err;
-		}
-	}
-
-	return 0;
-}
-
-static const struct of_device_id tango_nand_ids[] = {
-	{ .compatible = "sigma,smp8758-nand" },
-	{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, tango_nand_ids);
-
-static struct platform_driver tango_nand_driver = {
-	.probe	= tango_nand_probe,
-	.remove	= tango_nand_remove,
-	.driver	= {
-		.name		= "tango-nand",
-		.of_match_table	= tango_nand_ids,
-	},
-};
-
-module_platform_driver(tango_nand_driver);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Sigma Designs");
-MODULE_DESCRIPTION("Tango4 NAND Flash controller driver");