If the SPI bus number is provided by a DT alias, idr_alloc() is called twice, leading to:
WARNING: CPU: 1 PID: 1 at drivers/spi/spi.c:2179 spi_register_controller+0x11c/0x5d8 couldn't get idr
Fix this by moving the handling of fixed SPI bus numbers up, before the DT handling code fills in ctlr->bus_num.
Fixes: 1a4327fbf4554d5b ("spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbers") Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be --- Seen on e.g. r8a7791/koelsch, breaking both RSPI and MSIOF. --- drivers/spi/spi.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index a00d006d4c3a1c5a..9da0bc5a036cfff6 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2143,8 +2143,17 @@ int spi_register_controller(struct spi_controller *ctlr) */ if (ctlr->num_chipselect == 0) return -EINVAL; - /* allocate dynamic bus number using Linux idr */ - if ((ctlr->bus_num < 0) && ctlr->dev.of_node) { + if (ctlr->bus_num >= 0) { + /* 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; + } else if (ctlr->dev.of_node) { + /* allocate dynamic bus number using Linux idr */ id = of_alias_get_id(ctlr->dev.of_node, "spi"); if (id >= 0) { ctlr->bus_num = id; @@ -2170,15 +2179,6 @@ 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);