diff options
| author | Jiri Kosina <jkosina@suse.cz> | 2020-10-15 20:37:01 +0200 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2020-10-15 20:37:01 +0200 |
| commit | 62b31a045757eac81fed94b19df47418a0818528 (patch) | |
| tree | 285fda56df8304dff6ba929bad65ddfb4e4fd726 /drivers/spi/spi.c | |
| parent | cc51d171776f3a6acb6828bad0b780a4cacf5423 (diff) | |
| parent | c27e08820bc6cb7d483a8d87589bdbbbf10f2306 (diff) | |
Merge branch 'for-5.10/core' into for-linus
- nonblocking read semantics fix for hid-debug
Diffstat (limited to 'drivers/spi/spi.c')
| -rw-r--r-- | drivers/spi/spi.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 6626587e77b4..dc12af018350 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -475,6 +475,12 @@ static LIST_HEAD(spi_controller_list); */ static DEFINE_MUTEX(board_lock); +/* + * Prevents addition of devices with same chip select and + * addition of devices below an unregistering controller. + */ +static DEFINE_MUTEX(spi_add_lock); + /** * spi_alloc_device - Allocate a new SPI device * @ctlr: Controller to which device is connected @@ -554,7 +560,6 @@ static int spi_dev_check(struct device *dev, void *data) */ int spi_add_device(struct spi_device *spi) { - static DEFINE_MUTEX(spi_add_lock); struct spi_controller *ctlr = spi->controller; struct device *dev = ctlr->dev.parent; int status; @@ -582,6 +587,13 @@ int spi_add_device(struct spi_device *spi) goto done; } + /* Controller may unregister concurrently */ + if (IS_ENABLED(CONFIG_SPI_DYNAMIC) && + !device_is_registered(&ctlr->dev)) { + status = -ENODEV; + goto done; + } + /* Descriptors take precedence */ if (ctlr->cs_gpiods) spi->cs_gpiod = ctlr->cs_gpiods[spi->chip_select]; @@ -2795,6 +2807,10 @@ void spi_unregister_controller(struct spi_controller *ctlr) struct spi_controller *found; int id = ctlr->bus_num; + /* Prevent addition of new devices, unregister existing ones */ + if (IS_ENABLED(CONFIG_SPI_DYNAMIC)) + mutex_lock(&spi_add_lock); + device_for_each_child(&ctlr->dev, NULL, __unregister); /* First make sure that this controller was ever added */ @@ -2815,6 +2831,9 @@ void spi_unregister_controller(struct spi_controller *ctlr) if (found == ctlr) idr_remove(&spi_master_idr, id); mutex_unlock(&board_lock); + + if (IS_ENABLED(CONFIG_SPI_DYNAMIC)) + mutex_unlock(&spi_add_lock); } EXPORT_SYMBOL_GPL(spi_unregister_controller); |