bus: mhi: core: Add support for ringing channel/event ring doorbells

This commit adds support for ringing channel and event ring doorbells
by MHI host. The MHI host can use the channel and event ring doorbells
for notifying the client device about processing transfer and event
rings which it has queued using MMIO registers.

This is based on the patch submitted by Sujeev Dias:
https://lkml.org/lkml/2018/7/9/989

Signed-off-by: Sujeev Dias <[email protected]>
Signed-off-by: Siddartha Mohanadoss <[email protected]>
[mani: splitted from pm patch and cleaned up for upstream]
Signed-off-by: Manivannan Sadhasivam <[email protected]>
Reviewed-by: Jeffrey Hugo <[email protected]>
Tested-by: Jeffrey Hugo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index 1ce2bdd5f2f4..099d1643b072 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -240,6 +240,8 @@ struct mhi_controller_config {
  *            controller (required)
  * @mhi_dev: MHI device instance for the controller
  * @regs: Base address of MHI MMIO register space (required)
+ * @bhi: Points to base of MHI BHI register space
+ * @wake_db: MHI WAKE doorbell register address
  * @iova_start: IOMMU starting address for data (required)
  * @iova_stop: IOMMU stop address for data (required)
  * @fw_image: Firmware image name for normal booting (required)
@@ -294,6 +296,8 @@ struct mhi_controller {
 	struct device *cntrl_dev;
 	struct mhi_device *mhi_dev;
 	void __iomem *regs;
+	void __iomem *bhi;
+	void __iomem *wake_db;
 	dma_addr_t iova_start;
 	dma_addr_t iova_stop;
 	const char *fw_image;