Merge tag 'spi-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

[linux-2.6-block.git] / drivers / spi / spi.c

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7589c8af4368a7c2c4558531d216a332003f8102..51ad42fad567913339ab8d9deaf531b779865a87 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -851,6 +851,20 @@ static int __spi_unmap_msg(struct spi_master *master, struct spi_message *msg)
        return 0;
 }
 #else /* !CONFIG_HAS_DMA */
+static inline int spi_map_buf(struct spi_master *master,
+                             struct device *dev, struct sg_table *sgt,
+                             void *buf, size_t len,
+                             enum dma_data_direction dir)
+{
+       return -EINVAL;
+}
+
+static inline void spi_unmap_buf(struct spi_master *master,
+                                struct device *dev, struct sg_table *sgt,
+                                enum dma_data_direction dir)
+{
+}
+
 static inline int __spi_map_msg(struct spi_master *master,
                                struct spi_message *msg)
 {
@@ -1057,7 +1071,6 @@ 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
@@ -1067,8 +1080,7 @@ 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;
@@ -1140,6 +1152,8 @@ 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) {
@@ -1164,9 +1178,6 @@ 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) {
@@ -1196,8 +1207,7 @@ 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)
@@ -1213,7 +1223,7 @@ 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)
@@ -1886,6 +1896,7 @@ 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)
@@ -2738,6 +2749,7 @@ int spi_flash_read(struct spi_device *spi,
 
 {
        struct spi_master *master = spi->master;
+       struct device *rx_dev = NULL;
        int ret;
 
        if ((msg->opcode_nbits == SPI_NBITS_DUAL ||
@@ -2763,9 +2775,24 @@ int spi_flash_read(struct spi_device *spi,
                        return ret;
                }
        }
+
        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,
+                                 msg->buf, msg->len,
+                                 DMA_FROM_DEVICE);
+               if (!ret)
+                       msg->cur_msg_mapped = true;
+       }
        ret = master->spi_flash_read(spi, msg);
+       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)
                pm_runtime_put(master->dev.parent);
 
@@ -2785,8 +2812,7 @@ 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;
@@ -2804,9 +2830,6 @@ 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
@@ -2824,9 +2847,6 @@ 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.
@@ -2836,7 +2856,7 @@ 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);
@@ -2869,7 +2889,13 @@ 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);
 
@@ -2891,7 +2917,7 @@ 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);