Commit 10ea8bcd authored by Loic Poulain's avatar Loic Poulain Committed by Manivannan Sadhasivam
Browse files

bus: mhi: core: Fix device hierarchy 



This patch fixes the hierarchical structure of MHI devices. Indeed,
MHI client devices are directly 'enumerated' from the mhi controller
and therefore must be direct descendants/children of their mhi
controller device, in accordance with the Linux Device Model.

Today both MHI clients and controller devices are at the same level,
this patch ensures that MHI controller is parent of its client devices.

The hierarchy is especially important for power management (safe
suspend/resume order). It is also useful for userspace to determine
relationship between MHI client devices and controllers.

Signed-off-by: default avatarLoic Poulain <loic.poulain@linaro.org>
Reviewed-by: default avatarBjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: default avatarHemant Kumar <hemantk@codeaurora.org>
Signed-off-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
parent 206e7383

drivers/bus/mhi/core/debugfs.c

+3 −1
Original line number Diff line number Diff line
@@ -159,7 +159,9 @@ static int mhi_debugfs_devices_show(struct seq_file *m, void *d) 
		return -ENODEV;

	}



	device_for_each_child(mhi_cntrl->cntrl_dev, m, mhi_device_info_show);

	/* Show controller and client(s) info */

	mhi_device_info_show(&mhi_cntrl->mhi_dev->dev, m);

	device_for_each_child(&mhi_cntrl->mhi_dev->dev, m, mhi_device_info_show);



	return 0;

}

drivers/bus/mhi/core/init.c

+9 −1
Original line number Diff line number Diff line
@@ -1144,7 +1144,15 @@ struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl) 
	device_initialize(dev);

	dev->bus = &mhi_bus_type;

	dev->release = mhi_release_device;



	if (mhi_cntrl->mhi_dev) {

		/* for MHI client devices, parent is the MHI controller device */

		dev->parent = &mhi_cntrl->mhi_dev->dev;

	} else {

		/* for MHI controller device, parent is the bus device (e.g. pci device) */

		dev->parent = mhi_cntrl->cntrl_dev;

	}



	mhi_dev->mhi_cntrl = mhi_cntrl;

	mhi_dev->dev_wake = 0;

drivers/bus/mhi/core/pm.c

+2 −2
Original line number Diff line number Diff line
@@ -504,7 +504,7 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl) 
	wake_up_all(&mhi_cntrl->state_event);



	dev_dbg(dev, "Reset all active channels and remove MHI devices\n");

	device_for_each_child(mhi_cntrl->cntrl_dev, NULL, mhi_destroy_device);

	device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);



	mutex_lock(&mhi_cntrl->pm_mutex);
@@ -637,7 +637,7 @@ static void mhi_pm_sys_error_transition(struct mhi_controller *mhi_cntrl) 
	wake_up_all(&mhi_cntrl->state_event);



	dev_dbg(dev, "Reset all active channels and remove MHI devices\n");

	device_for_each_child(mhi_cntrl->cntrl_dev, NULL, mhi_destroy_device);

	device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device);



	mutex_lock(&mhi_cntrl->pm_mutex);