diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index c9a8d544e467..d2e7f1350ef6 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1069,7 +1069,6 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); * __spi_pump_messages - function which processes spi message queue * @master: master to process queue for * @in_kthread: true if we are in the context of the message pump thread - * @bus_locked: true if the bus mutex is held when calling this function * * This function checks if there is any spi message in the queue that * needs processing and if so call out to the driver to initialize hardware @@ -1079,8 +1078,7 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); * inside spi_sync(); the queue extraction handling at the top of the * function should deal with this safely. */ -static void __spi_pump_messages(struct spi_master *master, bool in_kthread, - bool bus_locked) +static void __spi_pump_messages(struct spi_master *master, bool in_kthread) { unsigned long flags; bool was_busy = false; @@ -1152,6 +1150,8 @@ static void __spi_pump_messages(struct spi_master *master, bool in_kthread, master->busy = true; spin_unlock_irqrestore(&master->queue_lock, flags); + mutex_lock(&master->io_mutex); + if (!was_busy && master->auto_runtime_pm) { ret = pm_runtime_get_sync(master->dev.parent); if (ret < 0) { @@ -1176,9 +1176,6 @@ static void __spi_pump_messages(struct spi_master *master, bool in_kthread, } } - if (!bus_locked) - mutex_lock(&master->bus_lock_mutex); - trace_spi_message_start(master->cur_msg); if (master->prepare_message) { @@ -1208,8 +1205,7 @@ static void __spi_pump_messages(struct spi_master *master, bool in_kthread, } out: - if (!bus_locked) - mutex_unlock(&master->bus_lock_mutex); + mutex_unlock(&master->io_mutex); /* Prod the scheduler in case transfer_one() was busy waiting */ if (!ret) @@ -1225,7 +1221,7 @@ static void spi_pump_messages(struct kthread_work *work) struct spi_master *master = container_of(work, struct spi_master, pump_messages); - __spi_pump_messages(master, true, master->bus_lock_flag); + __spi_pump_messages(master, true); } static int spi_init_queue(struct spi_master *master) @@ -1887,6 +1883,7 @@ int spi_register_master(struct spi_master *master) spin_lock_init(&master->queue_lock); spin_lock_init(&master->bus_lock_spinlock); mutex_init(&master->bus_lock_mutex); + mutex_init(&master->io_mutex); master->bus_lock_flag = 0; init_completion(&master->xfer_completion); if (!master->max_dma_len) @@ -2767,6 +2764,7 @@ int spi_flash_read(struct spi_device *spi, } mutex_lock(&master->bus_lock_mutex); + mutex_lock(&master->io_mutex); if (master->dma_rx) { rx_dev = master->dma_rx->device->dev; ret = spi_map_buf(master, rx_dev, &msg->rx_sg, @@ -2779,6 +2777,7 @@ int spi_flash_read(struct spi_device *spi, if (msg->cur_msg_mapped) spi_unmap_buf(master, rx_dev, &msg->rx_sg, DMA_FROM_DEVICE); + mutex_unlock(&master->io_mutex); mutex_unlock(&master->bus_lock_mutex); if (master->auto_runtime_pm) @@ -2800,8 +2799,7 @@ static void spi_complete(void *arg) complete(arg); } -static int __spi_sync(struct spi_device *spi, struct spi_message *message, - int bus_locked) +static int __spi_sync(struct spi_device *spi, struct spi_message *message) { DECLARE_COMPLETION_ONSTACK(done); int status; @@ -2819,9 +2817,6 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message, SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_sync); SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync); - if (!bus_locked) - mutex_lock(&master->bus_lock_mutex); - /* If we're not using the legacy transfer method then we will * try to transfer in the calling context so special case. * This code would be less tricky if we could remove the @@ -2839,9 +2834,6 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message, status = spi_async_locked(spi, message); } - if (!bus_locked) - mutex_unlock(&master->bus_lock_mutex); - if (status == 0) { /* Push out the messages in the calling context if we * can. @@ -2851,7 +2843,7 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message, spi_sync_immediate); SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync_immediate); - __spi_pump_messages(master, false, bus_locked); + __spi_pump_messages(master, false); } wait_for_completion(&done); @@ -2884,7 +2876,13 @@ static int __spi_sync(struct spi_device *spi, struct spi_message *message, */ int spi_sync(struct spi_device *spi, struct spi_message *message) { - return __spi_sync(spi, message, spi->master->bus_lock_flag); + int ret; + + mutex_lock(&spi->master->bus_lock_mutex); + ret = __spi_sync(spi, message); + mutex_unlock(&spi->master->bus_lock_mutex); + + return ret; } EXPORT_SYMBOL_GPL(spi_sync); @@ -2906,7 +2904,7 @@ EXPORT_SYMBOL_GPL(spi_sync); */ int spi_sync_locked(struct spi_device *spi, struct spi_message *message) { - return __spi_sync(spi, message, 1); + return __spi_sync(spi, message); } EXPORT_SYMBOL_GPL(spi_sync_locked); diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 7b53af4ba5f8..072cb2aa2413 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -312,8 +312,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @flags: other constraints relevant to this driver * @max_transfer_size: function that returns the max transfer size for * a &spi_device; may be %NULL, so the default %SIZE_MAX will be used. + * @io_mutex: mutex for physical bus access * @bus_lock_spinlock: spinlock for SPI bus locking - * @bus_lock_mutex: mutex for SPI bus locking + * @bus_lock_mutex: mutex for exclusion of multiple callers * @bus_lock_flag: indicates that the SPI bus is locked for exclusive use * @setup: updates the device mode and clocking records used by a * device's SPI controller; protocol code may call this. This @@ -446,6 +447,9 @@ struct spi_master { */ size_t (*max_transfer_size)(struct spi_device *spi); + /* I/O mutex */ + struct mutex io_mutex; + /* lock and mutex for SPI bus locking */ spinlock_t bus_lock_spinlock; struct mutex bus_lock_mutex;