diff options
| -rw-r--r-- | drivers/spi/spi.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 61f7bde8c7fb..8fbed4754de4 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -641,12 +641,26 @@ static inline int spi_dev_check_cs(struct device *dev, return 0; } +struct spi_dev_check_info { + struct spi_device *new_spi; + struct spi_device *parent; /* set for ancillary devices */ +}; + static int spi_dev_check(struct device *dev, void *data) { struct spi_device *spi = to_spi_device(dev); - struct spi_device *new_spi = data; + struct spi_dev_check_info *info = data; + struct spi_device *new_spi = info->new_spi; int status, idx; + /* + * When registering an ancillary device, skip checking against the + * parent device since the ancillary is intentionally using one of + * the parent's chip selects. + */ + if (info->parent && spi == info->parent) + return 0; + if (spi->controller == new_spi->controller) { for (idx = 0; idx < spi->num_chipselect; idx++) { status = spi_dev_check_cs(dev, spi, idx, new_spi, 0); @@ -663,10 +677,11 @@ static void spi_cleanup(struct spi_device *spi) spi->controller->cleanup(spi); } -static int __spi_add_device(struct spi_device *spi) +static int __spi_add_device(struct spi_device *spi, struct spi_device *parent) { struct spi_controller *ctlr = spi->controller; struct device *dev = ctlr->dev.parent; + struct spi_dev_check_info check_info; int status, idx; u8 cs; @@ -710,7 +725,9 @@ static int __spi_add_device(struct spi_device *spi) * chipselect **BEFORE** we call setup(), else we'll trash * its configuration. */ - status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); + check_info.new_spi = spi; + check_info.parent = parent; + status = bus_for_each_dev(&spi_bus_type, NULL, &check_info, spi_dev_check); if (status) return status; @@ -772,7 +789,7 @@ int spi_add_device(struct spi_device *spi) spi_dev_set_name(spi); mutex_lock(&ctlr->add_lock); - status = __spi_add_device(spi); + status = __spi_add_device(spi, NULL); mutex_unlock(&ctlr->add_lock); return status; } @@ -2715,8 +2732,8 @@ struct spi_device *spi_new_ancillary_device(struct spi_device *spi, WARN_ON(!mutex_is_locked(&ctlr->add_lock)); - /* Register the new device */ - rc = __spi_add_device(ancillary); + /* Register the new device, passing the parent to skip CS conflict check */ + rc = __spi_add_device(ancillary, spi); if (rc) { dev_err(&spi->dev, "failed to register ancillary device\n"); goto err_out; |