diff options
| -rw-r--r-- | drivers/spi/spi.c | 22 | ||||
| -rw-r--r-- | include/linux/spi/spi.h | 11 |
2 files changed, 33 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 8bef0c9a723..8a30c6b66a6 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -606,6 +606,18 @@ static void spi_pump_messages(struct kthread_work *work) trace_spi_message_start(master->cur_msg); + if (master->prepare_message) { + ret = master->prepare_message(master, master->cur_msg); + if (ret) { + dev_err(&master->dev, + "failed to prepare message: %d\n", ret); + master->cur_msg->status = ret; + spi_finalize_current_message(master); + return; + } + master->cur_msg_prepared = true; + } + ret = master->transfer_one_message(master, master->cur_msg); if (ret) { dev_err(&master->dev, @@ -687,6 +699,7 @@ void spi_finalize_current_message(struct spi_master *master) { struct spi_message *mesg; unsigned long flags; + int ret; spin_lock_irqsave(&master->queue_lock, flags); mesg = master->cur_msg; @@ -695,6 +708,15 @@ void spi_finalize_current_message(struct spi_master *master) queue_kthread_work(&master->kworker, &master->pump_messages); spin_unlock_irqrestore(&master->queue_lock, flags); + if (master->cur_msg_prepared && master->unprepare_message) { + ret = master->unprepare_message(master, mesg); + if (ret) { + dev_err(&master->dev, + "failed to unprepare message: %d\n", ret); + } + } + master->cur_msg_prepared = false; + mesg->state = NULL; if (mesg->complete) mesg->complete(mesg->context); diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 887116dbce2..000b50bee6c 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -257,6 +257,8 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @queue_lock: spinlock to syncronise access to message queue * @queue: message queue * @cur_msg: the currently in-flight message + * @cur_msg_prepared: spi_prepare_message was called for the currently + * in-flight message * @busy: message pump is busy * @running: message pump is running * @rt: whether this queue is set to run as a realtime task @@ -274,6 +276,10 @@ 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 + * @prepare_message: set up the controller to transfer a single message, + * for example doing DMA mapping. Called from threaded + * context. + * @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 * are not GPIOs (driven by the SPI controller itself). @@ -388,11 +394,16 @@ struct spi_master { bool running; bool rt; bool auto_runtime_pm; + bool cur_msg_prepared; int (*prepare_transfer_hardware)(struct spi_master *master); int (*transfer_one_message)(struct spi_master *master, struct spi_message *mesg); int (*unprepare_transfer_hardware)(struct spi_master *master); + int (*prepare_message)(struct spi_master *master, + struct spi_message *message); + int (*unprepare_message)(struct spi_master *master, + struct spi_message *message); /* gpio chip select */ int *cs_gpios; |