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| author | Kirill Kapranov <kirill.kapranov@compulab.co.il> | 2018-08-13 19:48:10 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2018-08-15 15:44:07 +0100 |
| commit | 1a4327fbf4554d5b78d75b19a13d40d6de220159 (patch) | |
| tree | 175422bba7026d50c01ae97cc6d0bbbbfaa975dc /drivers/spi/spi.c | |
| parent | 401c0d7712eb3189023efc9c0708a2ac984ed62e (diff) | |
| download | linux-1a4327fbf4554d5b78d75b19a13d40d6de220159.tar.gz linux-1a4327fbf4554d5b78d75b19a13d40d6de220159.tar.bz2 linux-1a4327fbf4554d5b78d75b19a13d40d6de220159.zip | |
spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers
On systems where some controllers get a dynamic ID assigned and some have
a fixed number (e.g. from ACPI tables), the current implementation might
run into an IDR collision: in case of a fixed bus number is gotten by a
driver (but not marked busy in IDR tree) and a driver with dynamic bus
number gets the same ID and predictably fails.
Fix this by means of checking-in fixed IDsin IDR as far as dynamic ones
at the moment of the controller registration.
Fixes: 9b61e302210e (spi: Pick spi bus number from Linux idr or spi alias)
Signed-off-by: Kirill Kapranov <kirill.kapranov@compulab.co.il>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ec395a6baf9c..a00d006d4c3a 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2170,6 +2170,15 @@ int spi_register_controller(struct spi_controller *ctlr) if (WARN(id < 0, "couldn't get idr")) return id; ctlr->bus_num = id; + } else { + /* devices with a fixed bus num must check-in with the num */ + mutex_lock(&board_lock); + id = idr_alloc(&spi_master_idr, ctlr, ctlr->bus_num, + ctlr->bus_num + 1, GFP_KERNEL); + mutex_unlock(&board_lock); + if (WARN(id < 0, "couldn't get idr")) + return id == -ENOSPC ? -EBUSY : id; + ctlr->bus_num = id; } INIT_LIST_HEAD(&ctlr->queue); spin_lock_init(&ctlr->queue_lock); |