[PATCH v2 10/21] bus: mhi: core: Introduce APIs to allocate and free the MHI controller

From: Manivannan Sadhasivam
Date: Mon Sep 28 2020 - 00:11:17 EST


From: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>

Client devices should use the APIs provided to allocate and free
the MHI controller structure. This will help ensure that the
structure is zero-initialized and there are no false positives
with respect to reading any values such as the serial number or
the OEM PK hash.

Suggested-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/bus/mhi/core/init.c | 16 ++++++++++++++++
include/linux/mhi.h | 12 ++++++++++++
2 files changed, 28 insertions(+)

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index e2011ec46b92..f69a2f3d039d 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -954,6 +954,22 @@ void mhi_unregister_controller(struct mhi_controller *mhi_cntrl)
}
EXPORT_SYMBOL_GPL(mhi_unregister_controller);

+struct mhi_controller *mhi_alloc_controller(void)
+{
+ struct mhi_controller *mhi_cntrl;
+
+ mhi_cntrl = kzalloc(sizeof(*mhi_cntrl), GFP_KERNEL);
+
+ return mhi_cntrl;
+}
+EXPORT_SYMBOL_GPL(mhi_alloc_controller);
+
+void mhi_free_controller(struct mhi_controller *mhi_cntrl)
+{
+ kfree(mhi_cntrl);
+}
+EXPORT_SYMBOL_GPL(mhi_free_controller);
+
int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl)
{
struct device *dev = &mhi_cntrl->mhi_dev->dev;
diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index 0c97f4bc5fae..6b987e8cc438 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -527,6 +527,18 @@ struct mhi_driver {
#define to_mhi_driver(drv) container_of(drv, struct mhi_driver, driver)
#define to_mhi_device(dev) container_of(dev, struct mhi_device, dev)

+/**
+ * mhi_alloc_controller - Allocate the MHI Controller structure
+ * Allocate the mhi_controller structure using zero initialized memory
+ */
+struct mhi_controller *mhi_alloc_controller(void);
+
+/**
+ * mhi_free_controller - Free the MHI Controller structure
+ * Free the mhi_controller structure which was previously allocated
+ */
+void mhi_free_controller(struct mhi_controller *mhi_cntrl);
+
/**
* mhi_register_controller - Register MHI controller
* @mhi_cntrl: MHI controller to register
--
2.17.1