[PATCH v5 03/10] bus: mhi: core: Use helper API to trigger a non-blocking host resume

Bhaumik Bhatt
2020-07-23T22:37:06Z

Autonomous low power mode support requires the MHI host to resume from
multiple places and post a wakeup source to exit system suspend. This
needs to be done in a non-blocking manner. Introduce a helper API to
trigger the host resume for data transfers and other non-blocking use
cases while supporting implementation of autonomous low power modes.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
drivers/bus/mhi/core/internal.h | 7 +++++++
drivers/bus/mhi/core/main.c | 21 +++++++--------------
drivers/bus/mhi/core/pm.c | 13 ++++---------
3 files changed, 18 insertions(+), 23 deletions(-)

diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h
index bcfa7b6..1bbd6e9 100644
--- a/drivers/bus/mhi/core/internal.h
+++ b/drivers/bus/mhi/core/internal.h
@@ -599,6 +599,13 @@ int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl);
int mhi_send_cmd(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan,
enum mhi_cmd_type cmd);

+static inline void mhi_trigger_resume(struct mhi_controller *mhi_cntrl)
+{
+ pm_wakeup_event(&mhi_cntrl->mhi_dev->dev, 0);
+ mhi_cntrl->runtime_get(mhi_cntrl);
+ mhi_cntrl->runtime_put(mhi_cntrl);
+}
+
/* Register access methods */
void mhi_db_brstmode(struct mhi_controller *mhi_cntrl, struct db_cfg *db_cfg,
void __iomem *db_addr, dma_addr_t db_val);
diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
index 1f622ce..79be18e 100644
--- a/drivers/bus/mhi/core/main.c
+++ b/drivers/bus/mhi/core/main.c
@@ -909,8 +909,7 @@ void mhi_ctrl_ev_task(unsigned long data)
* process it since we are probably in a suspended state,
* so trigger a resume.
*/
- mhi_cntrl->runtime_get(mhi_cntrl);
- mhi_cntrl->runtime_put(mhi_cntrl);
+ mhi_trigger_resume(mhi_cntrl);

return;
}
@@ -971,10 +970,8 @@ int mhi_queue_skb(struct mhi_device *mhi_dev, enum dma_data_direction dir,
}

/* we're in M3 or transitioning to M3 */
- if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) {
- mhi_cntrl->runtime_get(mhi_cntrl);
- mhi_cntrl->runtime_put(mhi_cntrl);
- }
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);

/* Toggle wake to exit out of M2 */
mhi_cntrl->wake_toggle(mhi_cntrl);
@@ -1032,10 +1029,8 @@ int mhi_queue_dma(struct mhi_device *mhi_dev, enum dma_data_direction dir,
}

/* we're in M3 or transitioning to M3 */
- if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) {
- mhi_cntrl->runtime_get(mhi_cntrl);
- mhi_cntrl->runtime_put(mhi_cntrl);
- }
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);

/* Toggle wake to exit out of M2 */
mhi_cntrl->wake_toggle(mhi_cntrl);
@@ -1147,10 +1142,8 @@ int mhi_queue_buf(struct mhi_device *mhi_dev, enum dma_data_direction dir,
read_lock_irqsave(&mhi_cntrl->pm_lock, flags);

/* we're in M3 or transitioning to M3 */
- if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) {
- mhi_cntrl->runtime_get(mhi_cntrl);
- mhi_cntrl->runtime_put(mhi_cntrl);
- }
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);

/* Toggle wake to exit out of M2 */
mhi_cntrl->wake_toggle(mhi_cntrl);
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 661d704..b227d41 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -824,11 +824,8 @@ int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl)
/* Wake up the device */
read_lock_bh(&mhi_cntrl->pm_lock);
mhi_cntrl->wake_get(mhi_cntrl, true);
- if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) {
- pm_wakeup_event(&mhi_cntrl->mhi_dev->dev, 0);
- mhi_cntrl->runtime_get(mhi_cntrl);
- mhi_cntrl->runtime_put(mhi_cntrl);
- }
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);
read_unlock_bh(&mhi_cntrl->pm_lock);

ret = wait_event_timeout(mhi_cntrl->state_event,
@@ -1139,10 +1136,8 @@ void mhi_device_put(struct mhi_device *mhi_dev)

mhi_dev->dev_wake--;
read_lock_bh(&mhi_cntrl->pm_lock);
- if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) {
- mhi_cntrl->runtime_get(mhi_cntrl);
- mhi_cntrl->runtime_put(mhi_cntrl);
- }
+ if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+ mhi_trigger_resume(mhi_cntrl);

mhi_cntrl->wake_put(mhi_cntrl, false);
read_unlock_bh(&mhi_cntrl->pm_lock);