bus: mhi: core: Remove pre_init flag used for power purposes

Some controllers can choose to skip preparation for power up.
In that case, device context is initialized based on the pre_init
flag not being set during mhi_prepare_for_power_up(). There is no
reason MHI host driver should maintain and provide controllers
with two separate paths for preparing MHI.

Going forward, all controllers will be required to call the
mhi_prepare_for_power_up() API followed by their choice of sync
or async power up. This allows MHI host driver to get rid of the
pre_init flag and sets up a common way for all controllers to use
MHI. This also helps controllers fail early on during preparation
phase in some failure cases.
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1617313309-24035-1-git-send-email-bbhatt@codeaurora.orgSigned-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

drivers/bus/mhi/core/init.c

@@ -1080,8 +1080,6 @@ int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
 			mhi_rddm_prepare(mhi_cntrl, mhi_cntrl->rddm_image);
 	}
 
-	mhi_cntrl->pre_init = true;
-
 	mutex_unlock(&mhi_cntrl->pm_mutex);
 
 	return 0;
@@ -1112,7 +1110,6 @@ void mhi_unprepare_after_power_down(struct mhi_controller *mhi_cntrl)
 	}
 
 	mhi_deinit_dev_ctxt(mhi_cntrl);
-	mhi_cntrl->pre_init = false;
 }
 EXPORT_SYMBOL_GPL(mhi_unprepare_after_power_down);
 

drivers/bus/mhi/core/pm.c

@@ -1062,13 +1062,6 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
 	mutex_lock(&mhi_cntrl->pm_mutex);
 	mhi_cntrl->pm_state = MHI_PM_DISABLE;
 
-	if (!mhi_cntrl->pre_init) {
-		/* Setup device context */
-		ret = mhi_init_dev_ctxt(mhi_cntrl);
-		if (ret)
-			goto error_dev_ctxt;
-	}
-
 	ret = mhi_init_irq_setup(mhi_cntrl);
 	if (ret)
 		goto error_setup_irq;
@@ -1150,10 +1143,6 @@ int mhi_async_power_up(struct mhi_controller *mhi_cntrl)
 	mhi_deinit_free_irq(mhi_cntrl);
 
 error_setup_irq:
-	if (!mhi_cntrl->pre_init)
-		mhi_deinit_dev_ctxt(mhi_cntrl);
-
-error_dev_ctxt:
 	mhi_cntrl->pm_state = MHI_PM_DISABLE;
 	mutex_unlock(&mhi_cntrl->pm_mutex);
 
@@ -1203,15 +1192,6 @@ void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
 	flush_work(&mhi_cntrl->st_worker);
 
 	free_irq(mhi_cntrl->irq[0], mhi_cntrl);
-
-	if (!mhi_cntrl->pre_init) {
-		/* Free all allocated resources */
-		if (mhi_cntrl->fbc_image) {
-			mhi_free_bhie_table(mhi_cntrl, mhi_cntrl->fbc_image);
-			mhi_cntrl->fbc_image = NULL;
-		}
-		mhi_deinit_dev_ctxt(mhi_cntrl);
-	}
 }
 EXPORT_SYMBOL_GPL(mhi_power_down);
 

include/linux/mhi.h

@@ -354,7 +354,6 @@ struct mhi_controller_config {
  * @index: Index of the MHI controller instance
  * @bounce_buf: Use of bounce buffer
  * @fbc_download: MHI host needs to do complete image transfer (optional)
- * @pre_init: MHI host needs to do pre-initialization before power up
  * @wake_set: Device wakeup set flag
  * @irq_flags: irq flags passed to request_irq (optional)
  *
@@ -447,7 +446,6 @@ struct mhi_controller {
 	int index;
 	bool bounce_buf;
 	bool fbc_download;
-	bool pre_init;
 	bool wake_set;
 	unsigned long irq_flags;
 };