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authorLinus Torvalds <torvalds@linux-foundation.org>2017-07-13 12:07:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-07-13 12:07:44 -0700
commitb5e16170f59b4ae38937b795a56a356fb95cca56 (patch)
tree7ed40053c10f5ce2982beb2195a2faf22a42d91e /drivers
parentda16dd9785f88680c4affe176c07e85067d4fdd7 (diff)
parent7d84120b5ba61912a5333f5fe2c4e8f35ef9514f (diff)
Merge tag 'for-linus-20170713' of git://git.infradead.org/linux-mtd
Pull MTD updates from Brian Norris: "General updates: - Cleanups and additional flash support for "dataflash" driver - new driver for mchp23k256 SPI SRAM device - improve handling of MTDs without eraseblocks (i.e., MTD_NO_ERASE) - refactor and improve "sub-partition" handling with TRX partition parser; partitions can now be created as sub-partitions of another partition SPINOR updates, from Cyrille Pitchen and Marek Vasut: - introduce support to the SPI 1-2-2 and 1-4-4 protocols. - introduce support to the Double Data Rate (DDR) mode. - introduce support to the Octo SPI protocols. - add support to new memory parts for Spansion, Macronix and Winbond. - add fixes for the Aspeed, STM32 and Cadence QSPI controler drivers. - clean up the st_spi_fsm driver. NAND updates, from Boris Brezillon: - addition of on-die ECC support to Micron driver - addition of helpers to help drivers choose most appropriate ECC settings - deletion of dead-code (cached programming and ->errstat() hook) - make sure drivers that do not support the SET/GET FEATURES command return ENOTSUPP use a dummy ->set/get_features implementation returning -ENOTSUPP (required for Micron on-die ECC) - change the semantic of ecc->write_page() for drivers setting the NAND_ECC_CUSTOM_PAGE_ACCESS flag - support exiting 'GET STATUS' command in default ->cmdfunc() implementations - change the prototype of ->setup_data_interface() A bunch of driver related changes: - various cleanup, fixes and improvements of the MTK driver - OMAP DT bindings fixes - support for ->setup_data_interface() in the fsmc driver - support for imx7 in the gpmi driver - finalization of the denali driver rework (thanks to Masahiro for the work he's done on this driver) - fix "bitflips in erased pages" handling in the ifc driver - addition of PM ops and dynamic timing configuration to the atmel driver" * tag 'for-linus-20170713' of git://git.infradead.org/linux-mtd: (118 commits) Documentation: ABI: mtd: describe "offset" more precisely mtd: Fix check in mtd_unpoint() mtd: nand: mtk: release lock on error path mtd: st_spi_fsm: remove SPINOR_OP_RDSR2 and use SPINOR_OP_RDCR instead mtd: spi-nor: cqspi: remove duplicate const mtd: spi-nor: Add support for Spansion S25FL064L mtd: spi-nor: Add support for mx66u51235f mtd: nand: mtk: add ->setup_data_interface() hook mtd: nand: mtk: remove unneeded mtk_ecc_hw_init from mtk_ecc_resume mtd: nand: mtk: remove unneeded mtk_nfc_hw_init from mtk_nfc_resume mtd: nand: mtk: disable ecc irq when writing page with hwecc mtd: nand: mtk: fix incorrect register setting order about ecc irq mtd: partitions: fixup some allocate_partition() whitespace mtd: parsers: trx: fix pr_err format for printing offset MAINTAINERS: Update SPI NOR subsystem git repositories mtd: extract TRX parser out of bcm47xxpart into a separated module mtd: partitions: add support for partition parsers mtd: partitions: add support for subpartitions mtd: partitions: rename "master" to the "parent" where appropriate mtd: partitions: remove sysfs files when deleting all master's partitions ...
Diffstat (limited to 'drivers')
-rw-r--r--drivers/mtd/Kconfig4
-rw-r--r--drivers/mtd/Makefile1
-rw-r--r--drivers/mtd/bcm47xxpart.c99
-rw-r--r--drivers/mtd/chips/cfi_cmdset_0020.c2
-rw-r--r--drivers/mtd/devices/Kconfig10
-rw-r--r--drivers/mtd/devices/Makefile1
-rw-r--r--drivers/mtd/devices/m25p80.c121
-rw-r--r--drivers/mtd/devices/mchp23k256.c236
-rw-r--r--drivers/mtd/devices/mtd_dataflash.c200
-rw-r--r--drivers/mtd/devices/serial_flash_cmds.h1
-rw-r--r--drivers/mtd/devices/st_spi_fsm.c4
-rw-r--r--drivers/mtd/maps/physmap_of_gemini.c2
-rw-r--r--drivers/mtd/mtdcore.c2
-rw-r--r--drivers/mtd/mtdpart.c370
-rw-r--r--drivers/mtd/nand/Kconfig3
-rw-r--r--drivers/mtd/nand/atmel/nand-controller.c354
-rw-r--r--drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c2
-rw-r--r--drivers/mtd/nand/cafe_nand.c2
-rw-r--r--drivers/mtd/nand/davinci_nand.c3
-rw-r--r--drivers/mtd/nand/denali.c1831
-rw-r--r--drivers/mtd/nand/denali.h315
-rw-r--r--drivers/mtd/nand/denali_dt.c53
-rw-r--r--drivers/mtd/nand/denali_pci.c26
-rw-r--r--drivers/mtd/nand/docg4.c2
-rw-r--r--drivers/mtd/nand/fsl_elbc_nand.c2
-rw-r--r--drivers/mtd/nand/fsl_ifc_nand.c81
-rw-r--r--drivers/mtd/nand/fsmc_nand.c122
-rw-r--r--drivers/mtd/nand/gpmi-nand/gpmi-lib.c6
-rw-r--r--drivers/mtd/nand/gpmi-nand/gpmi-nand.c75
-rw-r--r--drivers/mtd/nand/gpmi-nand/gpmi-nand.h13
-rw-r--r--drivers/mtd/nand/hisi504_nand.c2
-rw-r--r--drivers/mtd/nand/jz4780_nand.c2
-rw-r--r--drivers/mtd/nand/mpc5121_nfc.c2
-rw-r--r--drivers/mtd/nand/mtk_ecc.c228
-rw-r--r--drivers/mtd/nand/mtk_ecc.h2
-rw-r--r--drivers/mtd/nand/mtk_nand.c279
-rw-r--r--drivers/mtd/nand/mxc_nand.c12
-rw-r--r--drivers/mtd/nand/nand_base.c349
-rw-r--r--drivers/mtd/nand/nand_micron.c222
-rw-r--r--drivers/mtd/nand/orion_nand.c6
-rw-r--r--drivers/mtd/nand/pxa3xx_nand.c2
-rw-r--r--drivers/mtd/nand/qcom_nandc.c2
-rw-r--r--drivers/mtd/nand/s3c2410.c5
-rw-r--r--drivers/mtd/nand/sh_flctl.c2
-rw-r--r--drivers/mtd/nand/sunxi_nand.c9
-rw-r--r--drivers/mtd/nand/tango_nand.c22
-rw-r--r--drivers/mtd/nand/vf610_nfc.c2
-rw-r--r--drivers/mtd/parsers/Kconfig8
-rw-r--r--drivers/mtd/parsers/Makefile1
-rw-r--r--drivers/mtd/parsers/parser_trx.c126
-rw-r--r--drivers/mtd/spi-nor/Kconfig2
-rw-r--r--drivers/mtd/spi-nor/aspeed-smc.c183
-rw-r--r--drivers/mtd/spi-nor/atmel-quadspi.c83
-rw-r--r--drivers/mtd/spi-nor/cadence-quadspi.c20
-rw-r--r--drivers/mtd/spi-nor/fsl-quadspi.c6
-rw-r--r--drivers/mtd/spi-nor/hisi-sfc.c31
-rw-r--r--drivers/mtd/spi-nor/intel-spi.c7
-rw-r--r--drivers/mtd/spi-nor/mtk-quadspi.c15
-rw-r--r--drivers/mtd/spi-nor/nxp-spifi.c22
-rw-r--r--drivers/mtd/spi-nor/spi-nor.c488
-rw-r--r--drivers/mtd/spi-nor/stm32-quadspi.c32
-rw-r--r--drivers/mtd/tests/subpagetest.c2
-rw-r--r--drivers/staging/mt29f_spinand/mt29f_spinand.c2
63 files changed, 3950 insertions, 2169 deletions
diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index e83a279f1217..5a2d71729b9a 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -155,6 +155,10 @@ config MTD_BCM47XX_PARTS
This provides partitions parser for devices based on BCM47xx
boards.
+menu "Partition parsers"
+source "drivers/mtd/parsers/Kconfig"
+endmenu
+
comment "User Modules And Translation Layers"
#
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile
index 99bb9a1f6e16..151d60df303a 100644
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_MTD_AFS_PARTS) += afs.o
obj-$(CONFIG_MTD_AR7_PARTS) += ar7part.o
obj-$(CONFIG_MTD_BCM63XX_PARTS) += bcm63xxpart.o
obj-$(CONFIG_MTD_BCM47XX_PARTS) += bcm47xxpart.o
+obj-y += parsers/
# 'Users' - code which presents functionality to userspace.
obj-$(CONFIG_MTD_BLKDEVS) += mtd_blkdevs.o
diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index d10fa6c8f074..fe2581d9d882 100644
--- a/drivers/mtd/bcm47xxpart.c
+++ b/drivers/mtd/bcm47xxpart.c
@@ -43,7 +43,8 @@
#define ML_MAGIC2 0x26594131
#define TRX_MAGIC 0x30524448
#define SHSQ_MAGIC 0x71736873 /* shsq (weird ZTE H218N endianness) */
-#define UBI_EC_MAGIC 0x23494255 /* UBI# */
+
+static const char * const trx_types[] = { "trx", NULL };
struct trx_header {
uint32_t magic;
@@ -62,89 +63,6 @@ static void bcm47xxpart_add_part(struct mtd_partition *part, const char *name,
part->mask_flags = mask_flags;
}
-static const char *bcm47xxpart_trx_data_part_name(struct mtd_info *master,
- size_t offset)
-{
- uint32_t buf;
- size_t bytes_read;
- int err;
-
- err = mtd_read(master, offset, sizeof(buf), &bytes_read,
- (uint8_t *)&buf);
- if (err && !mtd_is_bitflip(err)) {
- pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
- offset, err);
- goto out_default;
- }
-
- if (buf == UBI_EC_MAGIC)
- return "ubi";
-
-out_default:
- return "rootfs";
-}
-
-static int bcm47xxpart_parse_trx(struct mtd_info *master,
- struct mtd_partition *trx,
- struct mtd_partition *parts,
- size_t parts_len)
-{
- struct trx_header header;
- size_t bytes_read;
- int curr_part = 0;
- int i, err;
-
- if (parts_len < 3) {
- pr_warn("No enough space to add TRX partitions!\n");
- return -ENOMEM;
- }
-
- err = mtd_read(master, trx->offset, sizeof(header), &bytes_read,
- (uint8_t *)&header);
- if (err && !mtd_is_bitflip(err)) {
- pr_err("mtd_read error while reading TRX header: %d\n", err);
- return err;
- }
-
- i = 0;
-
- /* We have LZMA loader if offset[2] points to sth */
- if (header.offset[2]) {
- bcm47xxpart_add_part(&parts[curr_part++], "loader",
- trx->offset + header.offset[i], 0);
- i++;
- }
-
- if (header.offset[i]) {
- bcm47xxpart_add_part(&parts[curr_part++], "linux",
- trx->offset + header.offset[i], 0);
- i++;
- }
-
- if (header.offset[i]) {
- size_t offset = trx->offset + header.offset[i];
- const char *name = bcm47xxpart_trx_data_part_name(master,
- offset);
-
- bcm47xxpart_add_part(&parts[curr_part++], name, offset, 0);
- i++;
- }
-
- /*
- * Assume that every partition ends at the beginning of the one it is
- * followed by.
- */
- for (i = 0; i < curr_part; i++) {
- u64 next_part_offset = (i < curr_part - 1) ?
- parts[i + 1].offset :
- trx->offset + trx->size;
-
- parts[i].size = next_part_offset - parts[i].offset;
- }
-
- return curr_part;
-}
-
/**
* bcm47xxpart_bootpartition - gets index of TRX partition used by bootloader
*
@@ -362,17 +280,10 @@ static int bcm47xxpart_parse(struct mtd_info *master,
for (i = 0; i < trx_num; i++) {
struct mtd_partition *trx = &parts[trx_parts[i]];
- if (i == bcm47xxpart_bootpartition()) {
- int num_parts;
-
- num_parts = bcm47xxpart_parse_trx(master, trx,
- parts + curr_part,
- BCM47XXPART_MAX_PARTS - curr_part);
- if (num_parts > 0)
- curr_part += num_parts;
- } else {
+ if (i == bcm47xxpart_bootpartition())
+ trx->types = trx_types;
+ else
trx->name = "failsafe";
- }
}
*pparts = parts;
diff --git a/drivers/mtd/chips/cfi_cmdset_0020.c b/drivers/mtd/chips/cfi_cmdset_0020.c
index 94d3eb42c4d5..7d342965f392 100644
--- a/drivers/mtd/chips/cfi_cmdset_0020.c
+++ b/drivers/mtd/chips/cfi_cmdset_0020.c
@@ -666,7 +666,7 @@ cfi_staa_writev(struct mtd_info *mtd, const struct kvec *vecs,
size_t totlen = 0, thislen;
int ret = 0;
size_t buflen = 0;
- static char *buffer;
+ char *buffer;
if (!ECCBUF_SIZE) {
/* We should fall back to a general writev implementation.
diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
index 58329d2dacd1..6def5445e03e 100644
--- a/drivers/mtd/devices/Kconfig
+++ b/drivers/mtd/devices/Kconfig
@@ -95,6 +95,16 @@ config MTD_M25P80
if you want to specify device partitioning or to use a device which
doesn't support the JEDEC ID instruction.
+config MTD_MCHP23K256
+ tristate "Microchip 23K256 SRAM"
+ depends on SPI_MASTER
+ help
+ This enables access to Microchip 23K256 SRAM chips, using SPI.
+
+ Set up your spi devices with the right board-specific
+ platform data, or a device tree description if you want to
+ specify device partitioning
+
config MTD_SPEAR_SMI
tristate "SPEAR MTD NOR Support through SMI controller"
depends on PLAT_SPEAR
diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile
index 7912d3a0ee34..f0f767624cc6 100644
--- a/drivers/mtd/devices/Makefile
+++ b/drivers/mtd/devices/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_MTD_LART) += lart.o
obj-$(CONFIG_MTD_BLOCK2MTD) += block2mtd.o
obj-$(CONFIG_MTD_DATAFLASH) += mtd_dataflash.o
obj-$(CONFIG_MTD_M25P80) += m25p80.o
+obj-$(CONFIG_MTD_MCHP23K256) += mchp23k256.o
obj-$(CONFIG_MTD_SPEAR_SMI) += spear_smi.o
obj-$(CONFIG_MTD_SST25L) += sst25l.o
obj-$(CONFIG_MTD_BCM47XXSFLASH) += bcm47xxsflash.o
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index c4df3b1bded0..00eea6fd379c 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -78,11 +78,17 @@ static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
{
struct m25p *flash = nor->priv;
struct spi_device *spi = flash->spi;
- struct spi_transfer t[2] = {};
+ unsigned int inst_nbits, addr_nbits, data_nbits, data_idx;
+ struct spi_transfer t[3] = {};
struct spi_message m;
int cmd_sz = m25p_cmdsz(nor);
ssize_t ret;
+ /* get transfer protocols. */
+ inst_nbits = spi_nor_get_protocol_inst_nbits(nor->write_proto);
+ addr_nbits = spi_nor_get_protocol_addr_nbits(nor->write_proto);
+ data_nbits = spi_nor_get_protocol_data_nbits(nor->write_proto);
+
spi_message_init(&m);
if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
@@ -92,12 +98,27 @@ static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
m25p_addr2cmd(nor, to, flash->command);
t[0].tx_buf = flash->command;
+ t[0].tx_nbits = inst_nbits;
t[0].len = cmd_sz;
spi_message_add_tail(&t[0], &m);
- t[1].tx_buf = buf;
- t[1].len = len;
- spi_message_add_tail(&t[1], &m);
+ /* split the op code and address bytes into two transfers if needed. */
+ data_idx = 1;
+ if (addr_nbits != inst_nbits) {
+ t[0].len = 1;
+
+ t[1].tx_buf = &flash->command[1];
+ t[1].tx_nbits = addr_nbits;
+ t[1].len = cmd_sz - 1;
+ spi_message_add_tail(&t[1], &m);
+
+ data_idx = 2;
+ }
+
+ t[data_idx].tx_buf = buf;
+ t[data_idx].tx_nbits = data_nbits;
+ t[data_idx].len = len;
+ spi_message_add_tail(&t[data_idx], &m);
ret = spi_sync(spi, &m);
if (ret)
@@ -109,18 +130,6 @@ static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
return ret;
}
-static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor)
-{
- switch (nor->flash_read) {
- case SPI_NOR_DUAL:
- return 2;
- case SPI_NOR_QUAD:
- return 4;
- default:
- return 0;
- }
-}
-
/*
* Read an address range from the nor chip. The address range
* may be any size provided it is within the physical boundaries.
@@ -130,13 +139,20 @@ static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
{
struct m25p *flash = nor->priv;
struct spi_device *spi = flash->spi;
- struct spi_transfer t[2];
+ unsigned int inst_nbits, addr_nbits, data_nbits, data_idx;
+ struct spi_transfer t[3];
struct spi_message m;
unsigned int dummy = nor->read_dummy;
ssize_t ret;
+ int cmd_sz;
+
+ /* get transfer protocols. */
+ inst_nbits = spi_nor_get_protocol_inst_nbits(nor->read_proto);
+ addr_nbits = spi_nor_get_protocol_addr_nbits(nor->read_proto);
+ data_nbits = spi_nor_get_protocol_data_nbits(nor->read_proto);
/* convert the dummy cycles to the number of bytes */
- dummy /= 8;
+ dummy = (dummy * addr_nbits) / 8;
if (spi_flash_read_supported(spi)) {
struct spi_flash_read_message msg;
@@ -149,10 +165,9 @@ static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
msg.read_opcode = nor->read_opcode;
msg.addr_width = nor->addr_width;
msg.dummy_bytes = dummy;
- /* TODO: Support other combinations */
- msg.opcode_nbits = SPI_NBITS_SINGLE;
- msg.addr_nbits = SPI_NBITS_SINGLE;
- msg.data_nbits = m25p80_rx_nbits(nor);
+ msg.opcode_nbits = inst_nbits;
+ msg.addr_nbits = addr_nbits;
+ msg.data_nbits = data_nbits;
ret = spi_flash_read(spi, &msg);
if (ret < 0)
@@ -167,20 +182,45 @@ static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
m25p_addr2cmd(nor, from, flash->command);
t[0].tx_buf = flash->command;
+ t[0].tx_nbits = inst_nbits;
t[0].len = m25p_cmdsz(nor) + dummy;
spi_message_add_tail(&t[0], &m);
- t[1].rx_buf = buf;
- t[1].rx_nbits = m25p80_rx_nbits(nor);
- t[1].len = min3(len, spi_max_transfer_size(spi),
- spi_max_message_size(spi) - t[0].len);
- spi_message_add_tail(&t[1], &m);
+ /*
+ * Set all dummy/mode cycle bits to avoid sending some manufacturer
+ * specific pattern, which might make the memory enter its Continuous
+ * Read mode by mistake.
+ * Based on the different mode cycle bit patterns listed and described
+ * in the JESD216B specification, the 0xff value works for all memories
+ * and all manufacturers.
+ */
+ cmd_sz = t[0].len;
+ memset(flash->command + cmd_sz - dummy, 0xff, dummy);
+
+ /* split the op code and address bytes into two transfers if needed. */
+ data_idx = 1;
+ if (addr_nbits != inst_nbits) {
+ t[0].len = 1;
+
+ t[1].tx_buf = &flash->command[1];
+ t[1].tx_nbits = addr_nbits;
+ t[1].len = cmd_sz - 1;
+ spi_message_add_tail(&t[1], &m);
+
+ data_idx = 2;
+ }
+
+ t[data_idx].rx_buf = buf;
+ t[data_idx].rx_nbits = data_nbits;
+ t[data_idx].len = min3(len, spi_max_transfer_size(spi),
+ spi_max_message_size(spi) - cmd_sz);
+ spi_message_add_tail(&t[data_idx], &m);
ret = spi_sync(spi, &m);
if (ret)
return ret;
- ret = m.actual_length - m25p_cmdsz(nor) - dummy;
+ ret = m.actual_length - cmd_sz;
if (ret < 0)
return -EIO;
return ret;
@@ -196,7 +236,11 @@ static int m25p_probe(struct spi_device *spi)
struct flash_platform_data *data;
struct m25p *flash;
struct spi_nor *nor;
- enum read_mode mode = SPI_NOR_NORMAL;
+ struct spi_nor_hwcaps hwcaps = {
+ .mask = SNOR_HWCAPS_READ |
+ SNOR_HWCAPS_READ_FAST |
+ SNOR_HWCAPS_PP,
+ };
char *flash_name;
int ret;
@@ -221,10 +265,19 @@ static int m25p_probe(struct spi_device *spi)
spi_set_drvdata(spi, flash);
flash->spi = spi;
- if (spi->mode & SPI_RX_QUAD)
- mode = SPI_NOR_QUAD;
- else if (spi->mode & SPI_RX_DUAL)
- mode = SPI_NOR_DUAL;
+ if (spi->mode & SPI_RX_QUAD) {
+ hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
+
+ if (spi->mode & SPI_TX_QUAD)
+ hwcaps.mask |= (SNOR_HWCAPS_READ_1_4_4 |
+ SNOR_HWCAPS_PP_1_1_4 |
+ SNOR_HWCAPS_PP_1_4_4);
+ } else if (spi->mode & SPI_RX_DUAL) {
+ hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
+
+ if (spi->mode & SPI_TX_DUAL)
+ hwcaps.mask |= SNOR_HWCAPS_READ_1_2_2;
+ }
if (data && data->name)
nor->mtd.name = data->name;
@@ -241,7 +294,7 @@ static int m25p_probe(struct spi_device *spi)
else
flash_name = spi->modalias;
- ret = spi_nor_scan(nor, flash_name, mode);
+ ret = spi_nor_scan(nor, flash_name, &hwcaps);
if (ret)
return ret;
diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c
new file mode 100644
index 000000000000..8956b7dcc984
--- /dev/null
+++ b/drivers/mtd/devices/mchp23k256.c
@@ -0,0 +1,236 @@
+/*
+ * mchp23k256.c
+ *
+ * Driver for Microchip 23k256 SPI RAM chips
+ *
+ * Copyright © 2016 Andrew Lunn <andrew@lunn.ch>
+ *
+ * This code 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/device.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/sizes.h>
+#include <linux/spi/flash.h>
+#include <linux/spi/spi.h>
+#include <linux/of_device.h>
+
+#define MAX_CMD_SIZE 4
+
+struct mchp23_caps {
+ u8 addr_width;
+ unsigned int size;
+};
+
+struct mchp23k256_flash {
+ struct spi_device *spi;
+ struct mutex lock;
+ struct mtd_info mtd;
+ const struct mchp23_caps *caps;
+};
+
+#define MCHP23K256_CMD_WRITE_STATUS 0x01
+#define MCHP23K256_CMD_WRITE 0x02
+#define MCHP23K256_CMD_READ 0x03
+#define MCHP23K256_MODE_SEQ BIT(6)
+
+#define to_mchp23k256_flash(x) container_of(x, struct mchp23k256_flash, mtd)
+
+static void mchp23k256_addr2cmd(struct mchp23k256_flash *flash,
+ unsigned int addr, u8 *cmd)
+{
+ int i;
+
+ /*
+ * Address is sent in big endian (MSB first) and we skip
+ * the first entry of the cmd array which contains the cmd
+ * opcode.
+ */
+ for (i = flash->caps->addr_width; i > 0; i--, addr >>= 8)
+ cmd[i] = addr;
+}
+
+static int mchp23k256_cmdsz(struct mchp23k256_flash *flash)
+{
+ return 1 + flash->caps->addr_width;
+}
+
+static int mchp23k256_write(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const unsigned char *buf)
+{
+ struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd);
+ struct spi_transfer transfer[2] = {};
+ struct spi_message message;
+ unsigned char command[MAX_CMD_SIZE];
+
+ spi_message_init(&message);
+
+ command[0] = MCHP23K256_CMD_WRITE;
+ mchp23k256_addr2cmd(flash, to, command);
+
+ transfer[0].tx_buf = command;
+ transfer[0].len = mchp23k256_cmdsz(flash);
+ spi_message_add_tail(&transfer[0], &message);
+
+ transfer[1].tx_buf = buf;
+ transfer[1].len = len;
+ spi_message_add_tail(&transfer[1], &message);
+
+ mutex_lock(&flash->lock);
+
+ spi_sync(flash->spi, &message);
+
+ if (retlen && message.actual_length > sizeof(command))
+ *retlen += message.actual_length - sizeof(command);
+
+ mutex_unlock(&flash->lock);
+ return 0;
+}
+
+static int mchp23k256_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, unsigned char *buf)
+{
+ struct mchp23k256_flash *fla