[PATCH] mtd:spi-nor: Add lock and unlock callback functions to struct spi_nor

From: vndao
Date: Mon Mar 16 2015 - 04:31:12 EST


From: VIET NGA DAO <vndao@xxxxxxxxxx>

This patch introduces a properly-replaceable spi_nor callback that does
flash specific lock and unlock. The existing code for spi_nor_lock and
spi_nor_unlock is moved into their own functions which are stm_lock and
stm_unlock.

Signed-off-by: VIET NGA DAO <vndao@xxxxxxxxxx>
---
drivers/mtd/spi-nor/spi-nor.c | 56 ++++++++++++++++++++++++++++---------------
include/linux/mtd/spi-nor.h | 4 ++++
2 files changed, 41 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index b6a5a0c..43bb552 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -369,17 +369,13 @@ erase_err:
return ret;
}

-static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+static int stm_lock(struct spi_nor *nor, loff_t ofs, uint64_t len)
{
- struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ struct mtd_info *mtd = nor->mtd;
uint32_t offset = ofs;
uint8_t status_old, status_new;
int ret = 0;

- ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_LOCK);
- if (ret)
- return ret;
-
status_old = read_sr(nor);

if (offset < mtd->size - (mtd->size / 2))
@@ -402,26 +398,18 @@ static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
(status_old & (SR_BP2 | SR_BP1 | SR_BP0))) {
write_enable(nor);
ret = write_sr(nor, status_new);
- if (ret)
- goto err;
}

-err:
- spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_LOCK);
return ret;
}

-static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
{
- struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ struct mtd_info *mtd = nor->mtd;
uint32_t offset = ofs;
uint8_t status_old, status_new;
int ret = 0;

- ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_UNLOCK);
- if (ret)
- return ret;
-
status_old = read_sr(nor);

if (offset+len > mtd->size - (mtd->size / 64))
@@ -444,15 +432,41 @@ static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
(status_old & (SR_BP2 | SR_BP1 | SR_BP0))) {
write_enable(nor);
ret = write_sr(nor, status_new);
- if (ret)
- goto err;
}

-err:
+ return ret;
+}
+
+static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ int ret;
+
+ ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_LOCK);
+ if (ret)
+ return ret;
+
+ ret = nor->flash_lock(nor, ofs, len);
+
spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_UNLOCK);
return ret;
}

+static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ struct spi_nor *nor = mtd_to_spi_nor(mtd);
+ int ret;
+
+ ret = spi_nor_lock_and_prep(nor, SPI_NOR_OPS_UNLOCK);
+ if (ret)
+ return ret;
+
+ ret = nor->flash_unlock(nor, ofs, len);
+
+ spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_LOCK);
+ return ret;
+}
+
/* Used when the "_ext_id" is two bytes at most */
#define INFO(_jedec_id, _ext_id, _sector_size, _n_sectors, _flags) \
((kernel_ulong_t)&(struct flash_info) { \
@@ -1045,6 +1059,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)

/* nor protection support for STmicro chips */
if (JEDEC_MFR(info) == CFI_MFR_ST) {
+ nor->flash_lock = stm_lock;
+ nor->flash_unlock = stm_unlock;
+ }
+ if (nor->flash_lock && nor->flash_unlock) {
mtd->_lock = spi_nor_lock;
mtd->_unlock = spi_nor_unlock;
}
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 4720b86..e4e73d5 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -155,6 +155,8 @@ enum spi_nor_option_flags {
* @write: [DRIVER-SPECIFIC] write data to the SPI NOR
* @erase: [DRIVER-SPECIFIC] erase a sector of the SPI NOR
* at the offset @offs
+ * @lock: [FLASH-SPECIFIC] lock a region of the SPI NOR
+ * @unlock: [FLASH-SPECIFIC] unlock a region of the SPI NOR
* @priv: the private data
*/
struct spi_nor {
@@ -188,6 +190,8 @@ struct spi_nor {
void (*write)(struct spi_nor *nor, loff_t to,
size_t len, size_t *retlen, const u_char *write_buf);
int (*erase)(struct spi_nor *nor, loff_t offs);
+ int (*flash_lock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
+ int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);

void *priv;
};
--
1.7.11.GIT

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