diff options
| -rw-r--r-- | drivers/spi/spi.c | 28 | ||||
| -rw-r--r-- | include/linux/spi/spi.h | 12 |
2 files changed, 27 insertions, 13 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 349ebba4b199..965dd8ac5939 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -370,6 +370,17 @@ static void spi_dev_set_name(struct spi_device *spi) spi->chip_select); } +static int spi_dev_check(struct device *dev, void *data) +{ + struct spi_device *spi = to_spi_device(dev); + struct spi_device *new_spi = data; + + if (spi->master == new_spi->master && + spi->chip_select == new_spi->chip_select) + return -EBUSY; + return 0; +} + /** * spi_add_device - Add spi_device allocated with spi_alloc_device * @spi: spi_device to register @@ -384,7 +395,6 @@ int spi_add_device(struct spi_device *spi) static DEFINE_MUTEX(spi_add_lock); struct spi_master *master = spi->master; struct device *dev = master->dev.parent; - struct device *d; int status; /* Chipselects are numbered 0..max; validate. */ @@ -404,12 +414,10 @@ int spi_add_device(struct spi_device *spi) */ mutex_lock(&spi_add_lock); - d = bus_find_device_by_name(&spi_bus_type, NULL, dev_name(&spi->dev)); - if (d != NULL) { + status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); + if (status) { dev_err(dev, "chipselect %d already in use\n", spi->chip_select); - put_device(d); - status = -EBUSY; goto done; } @@ -591,8 +599,10 @@ static int spi_transfer_one_message(struct spi_master *master, goto out; } - if (ret > 0) + if (ret > 0) { + ret = 0; wait_for_completion(&master->xfer_completion); + } trace_spi_transfer_stop(msg, xfer); @@ -632,7 +642,7 @@ out: * * Called by SPI drivers using the core transfer_one_message() * implementation to notify it that the current interrupt driven - * transfer has finised and the next one may be scheduled. + * transfer has finished and the next one may be scheduled. */ void spi_finalize_current_transfer(struct spi_master *master) { @@ -735,7 +745,9 @@ static void spi_pump_messages(struct kthread_work *work) ret = master->transfer_one_message(master, master->cur_msg); if (ret) { dev_err(&master->dev, - "failed to transfer one message from queue\n"); + "failed to transfer one message from queue: %d\n", ret); + master->cur_msg->status = ret; + spi_finalize_current_message(master); return; } } diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 8c62ba74dd91..9f5242df9311 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -277,15 +277,17 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @unprepare_transfer_hardware: there are currently no more messages on the * queue so the subsystem notifies the driver that it may relax the * hardware by issuing this call - * @set_cs: assert or deassert chip select, true to assert. May be called + * @set_cs: set the logic level of the chip select line. May be called * from interrupt context. * @prepare_message: set up the controller to transfer a single message, * for example doing DMA mapping. Called from threaded * context. - * @transfer_one: transfer a single spi_transfer. When the - * driver is finished with this transfer it must call - * spi_finalize_current_transfer() so the subsystem can issue - * the next transfer + * @transfer_one: transfer a single spi_transfer. + * - return 0 if the transfer is finished, + * - return 1 if the transfer is still in progress. When + * the driver is finished with this transfer it must + * call spi_finalize_current_transfer() so the subsystem + * can issue the next transfer * @unprepare_message: undo any work done by prepare_message(). * @cs_gpios: Array of GPIOs to use as chip select lines; one per CS * number. Any individual value may be -ENOENT for CS lines that |