[U-Boot] [PATCH 4/9] mtd: sf: Make sure we don't register the same device twice

Boris Brezillon
2018-11-19T11:51:16Z

spi_flash_mtd_register() can be called several times and each time it
will register the same mtd_info instance like if it was a new one.
The MTD ID allocation gets crazy when that happens, so let's track the
status of the sf_mtd_info object to avoid that.

Fixes: 9fe6d8716e09 ("mtd, spi: Add MTD layer driver")
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
Changes in v2
- None
---
drivers/mtd/spi/sf_mtd.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/spi/sf_mtd.c b/drivers/mtd/spi/sf_mtd.c
index 58d7e4439903..aabbc3589435 100644
--- a/drivers/mtd/spi/sf_mtd.c
+++ b/drivers/mtd/spi/sf_mtd.c
@@ -10,6 +10,7 @@
#include <spi_flash.h>

static struct mtd_info sf_mtd_info;
+static bool sf_mtd_registered;
static char sf_mtd_name[8];

static int spi_flash_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
@@ -73,6 +74,12 @@ static int spi_flash_mtd_number(void)

int spi_flash_mtd_register(struct spi_flash *flash)
{
+ int ret;
+
+ if (sf_mtd_registered)
+ del_mtd_device(&sf_mtd_info);
+
+ sf_mtd_registered = false;
memset(&sf_mtd_info, 0, sizeof(sf_mtd_info));
sprintf(sf_mtd_name, "nor%d", spi_flash_mtd_number());

@@ -94,7 +101,11 @@ int spi_flash_mtd_register(struct spi_flash *flash)
sf_mtd_info.numeraseregions = 0;
sf_mtd_info.erasesize = flash->sector_size;

- return add_mtd_device(&sf_mtd_info);
+ ret = add_mtd_device(&sf_mtd_info);
+ if (!ret)
+ sf_mtd_registered = true;
+
+ return ret;
}

void spi_flash_mtd_unregister(void)
--
2.17.1