diff options
| -rw-r--r-- | drivers/bus/mhi/core/main.c | 12 | ||||
| -rw-r--r-- | include/linux/mhi.h | 9 |
2 files changed, 21 insertions, 0 deletions
diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c index d34d7e90e38d..1202433ecf98 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -260,6 +260,18 @@ int mhi_destroy_device(struct device *dev, void *data) return 0; } +int mhi_get_free_desc_count(struct mhi_device *mhi_dev, + enum dma_data_direction dir) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ? + mhi_dev->ul_chan : mhi_dev->dl_chan; + struct mhi_ring *tre_ring = &mhi_chan->tre_ring; + + return get_nr_avail_ring_elements(mhi_cntrl, tre_ring); +} +EXPORT_SYMBOL_GPL(mhi_get_free_desc_count); + void mhi_notify(struct mhi_device *mhi_dev, enum mhi_callback cb_reason) { struct mhi_driver *mhi_drv; diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 562862ff819c..ece53a252217 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -599,6 +599,15 @@ void mhi_set_mhi_state(struct mhi_controller *mhi_cntrl, void mhi_notify(struct mhi_device *mhi_dev, enum mhi_callback cb_reason); /** + * mhi_get_free_desc_count - Get transfer ring length + * Get # of TD available to queue buffers + * @mhi_dev: Device associated with the channels + * @dir: Direction of the channel + */ +int mhi_get_free_desc_count(struct mhi_device *mhi_dev, + enum dma_data_direction dir); + +/** * mhi_prepare_for_power_up - Do pre-initialization before power up. * This is optional, call this before power up if * the controller does not want bus framework to |