Merge tag 'mhi-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi into char-misc-next

Manivannan writes:

MHI Host
========

- Added a new API mhi_power_down_keep_dev() to not destroy the struct dev
  associated with the MHI channels during MHI power down. This is useful in
  scenarios such as system suspend/hibernation where the probability of
  channels coming back is very high. So the PM maintainer suggested not to
  destroy the struct dev in those cases.

  This API is introduced for fixing the failure reported in the ath11k driver
  during resume from system suspend.

  NOTE: Due to the API dependency, the patch adding the API is pushed to an
  immutable branch (mhi-immutable) and merged into both mhi and ath trees. But
  the merge commit is not visible in mhi tree due to git being smart with
  'fast-forward'.

- Added an optional sysfs entry to force the MHI devices to enter the Emergency
  Download (EDL) mode to download the firmware from host.

- Added EDL mode support for Qcom SDX75/65/55 modems as per the MHI spec v1.2,
  Chapter 13.2. This involves writing a cookie to the EDL doorbell registers and
  then triggering the device reset from host.

* tag 'mhi-for-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi:
  bus: mhi: host: pci_generic: Add generic edl_trigger to allow devices to enter EDL mode
  bus: mhi: host: Add a new API for getting channel doorbell offset
  bus: mhi: host: Add sysfs entry to force device to enter EDL
  bus: mhi: host: Add mhi_power_down_keep_dev() API to support system suspend/hibernation

1 files changed, 28 insertions, 1 deletions

diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index 77b8c0a26674..b573f15762f8 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -353,6 +353,7 @@ struct mhi_controller_config {
  * @read_reg: Read a MHI register via the physical link (required)
  * @write_reg: Write a MHI register via the physical link (required)
  * @reset: Controller specific reset function (optional)
+ * @edl_trigger: CB function to trigger EDL mode (optional)
  * @buffer_len: Bounce buffer length
  * @index: Index of the MHI controller instance
  * @bounce_buf: Use of bounce buffer
@@ -435,6 +436,7 @@ struct mhi_controller {
 	void (*write_reg)(struct mhi_controller *mhi_cntrl, void __iomem *addr,
 			  u32 val);
 	void (*reset)(struct mhi_controller *mhi_cntrl);
+	int (*edl_trigger)(struct mhi_controller *mhi_cntrl);
 
 	size_t buffer_len;
 	int index;
@@ -630,13 +632,29 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl);
 int mhi_sync_power_up(struct mhi_controller *mhi_cntrl);
 
 /**
- * mhi_power_down - Start MHI power down sequence
+ * mhi_power_down - Power down the MHI device and also destroy the
+ *                  'struct device' for the channels associated with it.
+ *                  See also mhi_power_down_keep_dev() which is a variant
+ *                  of this API that keeps the 'struct device' for channels
+ *                  (useful during suspend/hibernation).
  * @mhi_cntrl: MHI controller
  * @graceful: Link is still accessible, so do a graceful shutdown process
  */
 void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful);
 
 /**
+ * mhi_power_down_keep_dev - Power down the MHI device but keep the 'struct
+ *                           device' for the channels associated with it.
+ *                           This is a variant of 'mhi_power_down()' and
+ *                           useful in scenarios such as suspend/hibernation
+ *                           where destroying of the 'struct device' is not
+ *                           needed.
+ * @mhi_cntrl: MHI controller
+ * @graceful: Link is still accessible, so do a graceful shutdown process
+ */
+void mhi_power_down_keep_dev(struct mhi_controller *mhi_cntrl, bool graceful);
+
+/**
  * mhi_unprepare_after_power_down - Free any allocated memory after power down
  * @mhi_cntrl: MHI controller
  */
@@ -798,4 +816,13 @@ int mhi_queue_skb(struct mhi_device *mhi_dev, enum dma_data_direction dir,
  */
 bool mhi_queue_is_full(struct mhi_device *mhi_dev, enum dma_data_direction dir);
 
+/**
+ * mhi_get_channel_doorbell_offset - Get the channel doorbell offset
+ * @mhi_cntrl: MHI controller
+ * @chdb_offset: Read channel doorbell offset
+ *
+ * Return: 0 if the read succeeds, a negative error code otherwise
+ */
+int mhi_get_channel_doorbell_offset(struct mhi_controller *mhi_cntrl, u32 *chdb_offset);
+
 #endif /* _MHI_H_ */