[PATCH v4 24/38] platform/x86: intel_scu_ipc: Add managed function to register SCU IPC

Mika Westerberg
2020-01-21T16:02:47Z

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 | 3 ++
drivers/platform/x86/intel_scu_ipc.c | 63 ++++++++++++++++++++++++++++
2 files changed, 66 insertions(+)

diff --git a/arch/x86/include/asm/intel_scu_ipc.h b/arch/x86/include/asm/intel_scu_ipc.h
index ce2ad516f0f9..23990b08c913 100644
--- a/arch/x86/include/asm/intel_scu_ipc.h
+++ b/arch/x86/include/asm/intel_scu_ipc.h
@@ -34,6 +34,9 @@ struct intel_scu_ipc_pdata {

struct intel_scu_ipc_dev *
intel_scu_ipc_register(struct device *dev, const struct intel_scu_ipc_pdata *pdata);
+void intel_scu_ipc_unregister(struct intel_scu_ipc_dev *scu);
+struct intel_scu_ipc_dev *
+devm_intel_scu_ipc_register(struct device *dev, const struct intel_scu_ipc_pdata *pdata);

struct intel_scu_ipc_dev *intel_scu_ipc_dev_get(void);
void intel_scu_ipc_dev_put(struct intel_scu_ipc_dev *scu);
diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c
index 391b65a4789e..3df2efa19d77 100644
--- a/drivers/platform/x86/intel_scu_ipc.c
+++ b/drivers/platform/x86/intel_scu_ipc.c
@@ -584,3 +584,66 @@ intel_scu_ipc_register(struct device *dev, const struct intel_scu_ipc_pdata *pda
return ERR_PTR(err);
}
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.
+ */
+void intel_scu_ipc_unregister(struct intel_scu_ipc_dev *scu)
+{
+ mutex_lock(&ipclock);
+ if (!WARN_ON(!scu->dev)) {
+ if (scu->irq > 0)
+ free_irq(scu->irq, scu);
+ iounmap(scu->ipc_base);
+ release_mem_region(scu->mem.start, resource_size(&scu->mem));
+ scu->dev = NULL;
+ }
+ 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
+ * @dev: SCU device
+ * @pdata: Platform specific data
+ *
+ * Call this function to initialize managed SCU IPC mechanism for @dev.
+ * Returns SCU IPC instance or ERR_PTR() if there was an error. 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 *dev,
+ const struct intel_scu_ipc_pdata *pdata)
+{
+ 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(dev, pdata);
+ if (IS_ERR(scu)) {
+ devres_free(devres);
+ return scu;
+ }
+
+ devres->scu = scu;
+ devres_add(dev, devres);
+
+ return scu;
+}
+EXPORT_SYMBOL_GPL(devm_intel_scu_ipc_register);
--
2.24.1