diff options
| author | Hemant Kumar <hemantk@codeaurora.org> | 2021-01-11 19:07:40 +0100 |
|---|---|---|
| committer | Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> | 2021-01-27 16:45:21 +0530 |
| commit | 87baa23e0236bc1c41ce744f524bf12dbe7fde66 (patch) | |
| tree | daa43475eda40c966431c5babde76cd3594c16c6 /drivers/bus | |
| parent | 5c8fe583cce542aa0b84adc939ce85293de36e5e (diff) | |
bus: mhi: core: Add helper API to return number of free TREs
Introduce mhi_get_free_desc_count() API to return number
of TREs available to queue buffer. MHI clients can use this
API to know before hand if ring is full without calling queue
API.
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1610388462-16322-1-git-send-email-loic.poulain@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Diffstat (limited to 'drivers/bus')
| -rw-r--r-- | drivers/bus/mhi/core/main.c | 12 |
1 files changed, 12 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; |