mtd: spi-nor: add mtd_is_locked() support

This enables ioctl(MEMISLOCKED). Status can now be reported in the
mtdinfo or flash_lock utilities found in mtd-utils.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 3db0f2b0ad45ea007d59dbdbe9b84ede82ba05e2..192aa8c1c8bf0627dea1613f8d0885cdc27174db 100644 (file)
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -549,6 +549,24 @@ static int stm_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len)
        return write_sr(nor, status_new);
 }
 
+/*
+ * Check if a region of the flash is (completely) locked. See stm_lock() for
+ * more info.
+ *
+ * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
+ * negative on errors.
+ */
+static int stm_is_locked(struct spi_nor *nor, loff_t ofs, uint64_t len)
+{
+       int status;
+
+       status = read_sr(nor);
+       if (status < 0)
+               return status;
+
+       return stm_is_locked_sr(nor, ofs, len, status);
+}
+
 static int spi_nor_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 {
        struct spi_nor *nor = mtd_to_spi_nor(mtd);
@@ -579,6 +597,21 @@ static int spi_nor_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
        return ret;
 }
 
+static int spi_nor_is_locked(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_is_locked(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)     \
                .id = {                                                 \
@@ -1186,11 +1219,13 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
        if (JEDEC_MFR(info) == SNOR_MFR_MICRON) {
                nor->flash_lock = stm_lock;
                nor->flash_unlock = stm_unlock;
+               nor->flash_is_locked = stm_is_locked;
        }
 
-       if (nor->flash_lock && nor->flash_unlock) {
+       if (nor->flash_lock && nor->flash_unlock && nor->flash_is_locked) {
                mtd->_lock = spi_nor_lock;
                mtd->_unlock = spi_nor_unlock;
+               mtd->_is_locked = spi_nor_is_locked;
        }
 
        /* sst nor chips use AAI word program */

diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 75eb1a079f758670f38d87a1b70993ca557241bf..c8723b62c4cd286aa7b6b382507dbb25cd975ab1 100644 (file)
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -147,6 +147,8 @@ struct mtd_info;
  *                     at the offset @offs
  * @flash_lock:                [FLASH-SPECIFIC] lock a region of the SPI NOR
  * @flash_unlock:      [FLASH-SPECIFIC] unlock a region of the SPI NOR
+ * @flash_is_locked:   [FLASH-SPECIFIC] check if a region of the SPI NOR is
+ *                     completely locked
  * @priv:              the private data
  */
 struct spi_nor {
@@ -178,6 +180,7 @@ struct spi_nor {
 
        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);
+       int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
 
        void *priv;
 };