[RFC] Special handling for NAND_CMD_PAGEPROG and NAND_CMD_READ0
Marc Gonzalez
marc_gonzalez at sigmadesigns.com
Wed Nov 9 09:57:04 PST 2016
Sample code to generate some discussion around having the framework
send I/O commands (for read_page and write_page) when it is dealing
with "high-level" NFCs that send the commands themselves.
---
drivers/mtd/nand/nand_base.c | 6 ++++--
drivers/mtd/nand/tango_nand.c | 7 ++++++-
include/linux/mtd/nand.h | 6 ++++++
3 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 50cdf37cb8e4..b4149101342c 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1970,7 +1970,8 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
__func__, buf);
read_retry:
- chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
+ if (!(chip->options & NAND_FOO))
+ chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
/*
* Now read the page into the buffer. Absent an error,
@@ -2681,7 +2682,8 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
if (!cached || !NAND_HAS_CACHEPROG(chip)) {
- chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+ if (!(chip->options & NAND_FOO))
+ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
status = chip->waitfunc(mtd, chip);
/*
* See if operation failed and additional status checks are
diff --git a/drivers/mtd/nand/tango_nand.c b/drivers/mtd/nand/tango_nand.c
index 74e39a92771c..d3679fdf2020 100644
--- a/drivers/mtd/nand/tango_nand.c
+++ b/drivers/mtd/nand/tango_nand.c
@@ -401,13 +401,17 @@ static int raw_write(struct nand_chip *chip, const u8 *buf, const u8 *oob)
static int tango_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
+ chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
return raw_read(chip, buf, chip->oob_poi);
}
static int tango_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
const uint8_t *buf, int oob_required, int page)
{
- return raw_write(chip, buf, chip->oob_poi);
+ /* what about NAND_CMD_SEQIN ? */
+ raw_write(chip, buf, chip->oob_poi);
+ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+ return 0;
}
static int tango_read_oob(struct mtd_info *mtd, struct nand_chip *chip, int page)
@@ -527,6 +531,7 @@ static int chip_init(struct device *dev, struct device_node *np)
chip->setup_data_interface = tango_set_timings;
chip->options = NAND_USE_BOUNCE_BUFFER
| NAND_NO_SUBPAGE_WRITE
+ | NAND_FOO
| NAND_WAIT_TCCS;
chip->controller = &nfc->hw;
tchip->base = nfc->pbus_base + (cs * 256);
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 06d0c9d740f7..fd8968f3ccca 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -220,6 +220,12 @@ enum nand_ecc_algo {
*/
#define NAND_WAIT_TCCS 0x00200000
+/*
+ * Controller sends NAND_CMD_PAGEPROG (write_page) and NAND_CMD_READ0 (read_page)
+ * therefore the framework should not send these commands.
+ */
+#define NAND_FOO 0x00400000
+
/* Options set by nand scan */
/* Nand scan has allocated controller struct */
#define NAND_CONTROLLER_ALLOC 0x80000000
--
2.1.4
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