diff options
Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r-- | drivers/spi/spi.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 6e65524cbfd9..b33a727a0158 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -45,7 +45,6 @@ #define CREATE_TRACE_POINTS #include <trace/events/spi.h> -#define SPI_DYN_FIRST_BUS_NUM 0 static DEFINE_IDR(spi_master_idr); @@ -2086,7 +2085,7 @@ int spi_register_controller(struct spi_controller *ctlr) struct device *dev = ctlr->dev.parent; struct boardinfo *bi; int status = -ENODEV; - int id; + int id, first_dynamic; if (!dev) return -ENODEV; @@ -2116,9 +2115,15 @@ int spi_register_controller(struct spi_controller *ctlr) } } if (ctlr->bus_num < 0) { + first_dynamic = of_alias_get_highest_id("spi"); + if (first_dynamic < 0) + first_dynamic = 0; + else + first_dynamic++; + mutex_lock(&board_lock); - id = idr_alloc(&spi_master_idr, ctlr, SPI_DYN_FIRST_BUS_NUM, 0, - GFP_KERNEL); + id = idr_alloc(&spi_master_idr, ctlr, first_dynamic, + 0, GFP_KERNEL); mutex_unlock(&board_lock); if (WARN(id < 0, "couldn't get idr")) return id; @@ -2195,7 +2200,7 @@ static void devm_spi_unregister(struct device *dev, void *res) * Context: can sleep * * Register a SPI device as with spi_register_controller() which will - * automatically be unregister + * automatically be unregistered and freed. * * Return: zero on success, else a negative error code. */ @@ -2236,15 +2241,18 @@ static int __unregister(struct device *dev, void *null) * only ones directly touching chip registers. * * This must be called from context that can sleep. + * + * Note that this function also drops a reference to the controller. */ void spi_unregister_controller(struct spi_controller *ctlr) { struct spi_controller *found; + int id = ctlr->bus_num; int dummy; /* First make sure that this controller was ever added */ mutex_lock(&board_lock); - found = idr_find(&spi_master_idr, ctlr->bus_num); + found = idr_find(&spi_master_idr, id); mutex_unlock(&board_lock); if (found != ctlr) { dev_dbg(&ctlr->dev, @@ -2264,7 +2272,7 @@ void spi_unregister_controller(struct spi_controller *ctlr) device_unregister(&ctlr->dev); /* free bus id */ mutex_lock(&board_lock); - idr_remove(&spi_master_idr, ctlr->bus_num); + idr_remove(&spi_master_idr, id); mutex_unlock(&board_lock); } EXPORT_SYMBOL_GPL(spi_unregister_controller); |