[PATCH v5 07/18] platform/x86: intel_scu_ipc: Add managed function to register SCU IPC

Mika Westerberg
2020-02-11T13:26:53Z

Drivers such as intel_pmc_ipc.c can be unloaded as well so in order to
support those in this driver add a new function that can be called to
unregister the SCU IPC when it is not needed anymore.

We also add a managed version of the intel_scu_ipc_register() that takes
care of calling intel_scu_ipc_unregister() automatically when the driver
is unbound.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
arch/x86/include/asm/intel_scu_ipc.h | 10 +++++
drivers/platform/x86/intel_scu_ipc.c | 63 ++++++++++++++++++++++++++++
2 files changed, 73 insertions(+)

diff --git a/arch/x86/include/asm/intel_scu_ipc.h b/arch/x86/include/asm/intel_scu_ipc.h
index 27041fe999e9..2463ff5cad5b 100644
--- a/arch/x86/include/asm/intel_scu_ipc.h
+++ b/arch/x86/include/asm/intel_scu_ipc.h
@@ -25,6 +25,16 @@ __intel_scu_ipc_register(struct device *parent,
#define intel_scu_ipc_register(parent, pdata) \
__intel_scu_ipc_register(parent, pdata, THIS_MODULE)

+void intel_scu_ipc_unregister(struct intel_scu_ipc_dev *scu);
+
+struct intel_scu_ipc_dev *
+__devm_intel_scu_ipc_register(struct device *parent,
+ const struct intel_scu_ipc_pdata *pdata,
+ struct module *owner);
+
+#define devm_intel_scu_ipc_register(parent, pdata) \
+ __devm_intel_scu_ipc_register(parent, pdata, THIS_MODULE)
+
struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void);
void intel_scu_ipc_dev_put(struct intel_scu_ipc_dev *scu);
struct intel_scu_ipc_dev *devm_intel_scu_ipc_dev_get(struct device *dev);
diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c
index b9e77facf280..58b3d4a48ae2 100644
--- a/drivers/platform/x86/intel_scu_ipc.c
+++ b/drivers/platform/x86/intel_scu_ipc.c
@@ -639,6 +639,69 @@ __intel_scu_ipc_register(struct device *parent,
}
EXPORT_SYMBOL_GPL(__intel_scu_ipc_register);

+/**
+ * intel_scu_ipc_unregister() - Unregister SCU IPC
+ * @scu: SCU IPC handle
+ *
+ * This unregisters the SCU IPC device and releases the acquired
+ * resources once the refcount goes to zero.
+ */
+void intel_scu_ipc_unregister(struct intel_scu_ipc_dev *scu)
+{
+ mutex_lock(&ipclock);
+ if (!WARN_ON(!ipcdev)) {
+ ipcdev = NULL;
+ device_unregister(&scu->dev);
+ }
+ mutex_unlock(&ipclock);
+}
+EXPORT_SYMBOL_GPL(intel_scu_ipc_unregister);
+
+static void devm_intel_scu_ipc_unregister(struct device *dev, void *res)
+{
+ struct intel_scu_ipc_devres *devres = res;
+ struct intel_scu_ipc_dev *scu = devres->scu;
+
+ intel_scu_ipc_unregister(scu);
+}
+
+/**
+ * __devm_intel_scu_ipc_register() - Register managed SCU IPC device
+ * @parent: Parent device
+ * @pdata: Platform specific data
+ * @owner: Module registering the SCU IPC device
+ *
+ * Call this function to register managed SCU IPC mechanism under
+ * @parent. Returns pointer to the new SCU IPC device or ERR_PTR() in
+ * case of failure. The caller may use the returned instance if it needs
+ * to do SCU IPC calls itself.
+ */
+struct intel_scu_ipc_dev *
+__devm_intel_scu_ipc_register(struct device *parent,
+ const struct intel_scu_ipc_pdata *pdata,
+ struct module *owner)
+{
+ struct intel_scu_ipc_devres *devres;
+ struct intel_scu_ipc_dev *scu;
+
+ devres = devres_alloc(devm_intel_scu_ipc_unregister, sizeof(*devres),
+ GFP_KERNEL);
+ if (!devres)
+ return NULL;
+
+ scu = __intel_scu_ipc_register(parent, pdata, owner);
+ if (IS_ERR(scu)) {
+ devres_free(devres);
+ return scu;
+ }
+
+ devres->scu = scu;
+ devres_add(parent, devres);
+
+ return scu;
+}
+EXPORT_SYMBOL_GPL(__devm_intel_scu_ipc_register);
+
static int __init intel_scu_ipc_init(void)
{
return class_register(&intel_scu_ipc_class);
--
2.25.0