[PATCH v4 02/15] mtd: nand: store nand ID in struct nand_chip

From: Boris Brezillon
Date: Tue Jan 03 2017 - 12:06:05 EST


Store the NAND ID in struct nand_chip to avoid passing id_data and id_len
as function parameters.

Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/nand_base.c | 55 ++++++++++++++++++++++++--------------------
include/linux/mtd/nand.h | 13 +++++++++++
2 files changed, 43 insertions(+), 25 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 6950978e77f5..309f2e113d39 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -3781,18 +3781,16 @@ static int nand_get_bits_per_cell(u8 cellinfo)
* chip. The rest of the parameters must be decoded according to generic or
* manufacturer-specific "extended ID" decoding patterns.
*/
-static void nand_decode_ext_id(struct nand_chip *chip, u8 id_data[8],
- int *busw)
+static void nand_decode_ext_id(struct nand_chip *chip, int *busw)
{
struct mtd_info *mtd = nand_to_mtd(chip);
- int extid, id_len;
+ int extid, id_len = chip->id.len;
+ u8 *id_data = chip->id.data;
/* The 3rd id byte holds MLC / multichip data */
chip->bits_per_cell = nand_get_bits_per_cell(id_data[2]);
/* The 4th id byte is the important one */
extid = id_data[3];

- id_len = nand_id_len(id_data, 8);
-
/*
* Field definitions are in the following datasheets:
* Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
@@ -3916,9 +3914,10 @@ static void nand_decode_ext_id(struct nand_chip *chip, u8 id_data[8],
* the chip.
*/
static void nand_decode_id(struct nand_chip *chip, struct nand_flash_dev *type,
- u8 id_data[8], int *busw)
+ int *busw)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *id_data = chip->id.data;
int maf_id = id_data[0];

mtd->erasesize = type->erasesize;
@@ -3948,9 +3947,10 @@ static void nand_decode_id(struct nand_chip *chip, struct nand_flash_dev *type,
* heuristic patterns using various detected parameters (e.g., manufacturer,
* page size, cell-type information).
*/
-static void nand_decode_bbm_options(struct nand_chip *chip, u8 id_data[8])
+static void nand_decode_bbm_options(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *id_data = chip->id.data;
int maf_id = id_data[0];

/* Set the bad block position */
@@ -3986,10 +3986,10 @@ static inline bool is_full_id_nand(struct nand_flash_dev *type)
}

static bool find_full_id_nand(struct nand_chip *chip,
- struct nand_flash_dev *type, u8 *id_data,
- int *busw)
+ struct nand_flash_dev *type, int *busw)
{
struct mtd_info *mtd = nand_to_mtd(chip);
+ u8 *id_data = chip->id.data;

if (!strncmp(type->id, id_data, type->id_len)) {
mtd->writesize = type->pagesize;
@@ -4018,13 +4018,13 @@ static bool find_full_id_nand(struct nand_chip *chip,
* Get the flash and manufacturer id and lookup if the type is supported.
*/
static int nand_get_flash_type(struct nand_chip *chip,
- int *maf_id, int *dev_id,
struct nand_flash_dev *type)
{
struct mtd_info *mtd = nand_to_mtd(chip);
int busw;
int i, maf_idx;
- u8 id_data[8];
+ u8 *id_data = chip->id.data;
+ u8 maf_id, dev_id;

/*
* Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
@@ -4039,8 +4039,8 @@ static int nand_get_flash_type(struct nand_chip *chip,
chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);

/* Read manufacturer and device IDs */
- *maf_id = chip->read_byte(mtd);
- *dev_id = chip->read_byte(mtd);
+ maf_id = chip->read_byte(mtd);
+ dev_id = chip->read_byte(mtd);

/*
* Try again to make sure, as some systems the bus-hold or other
@@ -4055,20 +4055,22 @@ static int nand_get_flash_type(struct nand_chip *chip,
for (i = 0; i < 8; i++)
id_data[i] = chip->read_byte(mtd);

- if (id_data[0] != *maf_id || id_data[1] != *dev_id) {
+ if (id_data[0] != maf_id || id_data[1] != dev_id) {
pr_info("second ID read did not match %02x,%02x against %02x,%02x\n",
- *maf_id, *dev_id, id_data[0], id_data[1]);
+ maf_id, dev_id, id_data[0], id_data[1]);
return -ENODEV;
}

+ chip->id.len = nand_id_len(id_data, 8);
+
if (!type)
type = nand_flash_ids;

for (; type->name != NULL; type++) {
if (is_full_id_nand(type)) {
- if (find_full_id_nand(chip, type, id_data, &busw))
+ if (find_full_id_nand(chip, type, &busw))
goto ident_done;
- } else if (*dev_id == type->dev_id) {
+ } else if (dev_id == type->dev_id) {
break;
}
}
@@ -4094,9 +4096,9 @@ static int nand_get_flash_type(struct nand_chip *chip,

if (!type->pagesize) {
/* Decode parameters from extended ID */
- nand_decode_ext_id(chip, id_data, &busw);
+ nand_decode_ext_id(chip, &busw);
} else {
- nand_decode_id(chip, type, id_data, &busw);
+ nand_decode_id(chip, type, &busw);
}
/* Get chip options */
chip->options |= type->options;
@@ -4105,13 +4107,13 @@ static int nand_get_flash_type(struct nand_chip *chip,
* Check if chip is not a Samsung device. Do not clear the
* options for chips which do not have an extended id.
*/
- if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
+ if (maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
ident_done:

/* Try to identify manufacturer */
for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
- if (nand_manuf_ids[maf_idx].id == *maf_id)
+ if (nand_manuf_ids[maf_idx].id == maf_id)
break;
}

@@ -4125,7 +4127,7 @@ static int nand_get_flash_type(struct nand_chip *chip,
* chip correct!
*/
pr_info("device found, Manufacturer ID: 0x%02x, Chip ID: 0x%02x\n",
- *maf_id, *dev_id);
+ maf_id, dev_id);
pr_info("%s %s\n", nand_manuf_ids[maf_idx].name, mtd->name);
pr_warn("bus width %d instead %d bit\n",
(chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
@@ -4133,7 +4135,7 @@ static int nand_get_flash_type(struct nand_chip *chip,
return -EINVAL;
}

- nand_decode_bbm_options(chip, id_data);
+ nand_decode_bbm_options(chip);

/* Calculate the address shift from the page size */
chip->page_shift = ffs(mtd->writesize) - 1;
@@ -4157,7 +4159,7 @@ static int nand_get_flash_type(struct nand_chip *chip,
chip->cmdfunc = nand_command_lp;

pr_info("device found, Manufacturer ID: 0x%02x, Chip ID: 0x%02x\n",
- *maf_id, *dev_id);
+ maf_id, dev_id);

if (chip->onfi_version)
pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
@@ -4360,7 +4362,7 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips,
nand_set_defaults(chip, chip->options & NAND_BUSWIDTH_16);

/* Read the flash type */
- ret = nand_get_flash_type(chip, &nand_maf_id, &nand_dev_id, table);
+ ret = nand_get_flash_type(chip, table);
if (ret) {
if (!(chip->options & NAND_SCAN_SILENT_NODEV))
pr_warn("No NAND device found\n");
@@ -4385,6 +4387,9 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips,
if (ret)
return ret;

+ nand_maf_id = chip->id.data[0];
+ nand_dev_id = chip->id.data[1];
+
chip->select_chip(mtd, -1);

/* Check for a chip array */
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index c5f3a012ae62..632975146c30 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -465,6 +465,17 @@ struct nand_jedec_params {
} __packed;

/**
+ * struct nand_id - NAND id structure
+ * @data: buffer containing the id bytes. Currently 8 bytes large, but can
+ * be extended if required.
+ * @len: ID length.
+ */
+struct nand_id {
+ u8 data[8];
+ int len;
+};
+
+/**
* struct nand_hw_control - Control structure for hardware controller (e.g ECC generator) shared among independent devices
* @lock: protection lock
* @active: the mtd device which holds the controller currently
@@ -793,6 +804,7 @@ nand_get_sdr_timings(const struct nand_data_interface *conf)
* @pagebuf_bitflips: [INTERN] holds the bitflip count for the page which is
* currently in data_buf.
* @subpagesize: [INTERN] holds the subpagesize
+ * @id: [INTERN] holds NAND ID
* @onfi_version: [INTERN] holds the chip ONFI version (BCD encoded),
* non 0 if ONFI supported.
* @jedec_version: [INTERN] holds the chip JEDEC version (BCD encoded),
@@ -877,6 +889,7 @@ struct nand_chip {
int badblockpos;
int badblockbits;

+ struct nand_id id;
int onfi_version;
int jedec_version;
union {
--
2.7.4