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| author | Masahiro Yamada <yamada.masahiro@socionext.com> | 2018-08-27 16:01:41 +0900 |
|---|---|---|
| committer | Boris Brezillon <boris.brezillon@bootlin.com> | 2018-08-27 20:41:46 +0200 |
| commit | 336d139f8718b1336c9d22f0e462611ae1229850 (patch) | |
| tree | 51eb6f3050d577daf90ee79b313cd7d3634d17dd /drivers | |
| parent | 166cd4421b0dabd2e438f5384f4ecf930dc8ab08 (diff) | |
| download | linux-336d139f8718b1336c9d22f0e462611ae1229850.tar.bz2 | |
mtd: rawnand: denali: do not pass zero maxchips to nand_scan()
Commit 49aa76b16676 ("mtd: rawnand: do not execute nand_scan_ident()
if maxchips is zero") gave a new meaning for calling nand_scan_ident()
with maxchips=0.
It is a special usage for some drivers such as docg4, but actually
the Denali driver may pass maxchips=0 to nand_scan() when the driver
is enabled but no NAND chip is found on the board for some reasons.
If nand_scan_with_ids() is called with maxchips=0, nand_scan_ident()
is skipped, then nand_set_defaults() is skipped as well. Thus, the
driver must set chip->controller beforehand. Otherwise, nand_attach()
causes NULL pointer dereference.
In fact, the Denali controller knows the number of connected chips
before calling nand_scan_ident(); if DEVICE_RESET fails, there is no
chip in that chip select. Then, denali_reset_banks() sets the maxchips
to the number of detected chips. If no chip is found, maxchips is zero.
In this case, there is no point for calling nand_scan() because we know
it will fail for sure. Let's make the probe function fail immediately.
Fixes: 49aa76b16676 ("mtd: rawnand: do not execute nand_scan_ident() if maxchips is zero")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mtd/nand/raw/denali.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/denali.c b/drivers/mtd/nand/raw/denali.c index ca18612c4201..67b2065e7a19 100644 --- a/drivers/mtd/nand/raw/denali.c +++ b/drivers/mtd/nand/raw/denali.c @@ -1338,6 +1338,11 @@ int denali_init(struct denali_nand_info *denali) denali_enable_irq(denali); denali_reset_banks(denali); + if (!denali->max_banks) { + /* Error out earlier if no chip is found for some reasons. */ + ret = -ENODEV; + goto disable_irq; + } denali->active_bank = DENALI_INVALID_BANK; |