Drivers: hv: vmbus: Convert acpi_device to more generic platform_device

VMBus driver code currently has direct dependency on ACPI and struct
acpi_device.  As a staging step toward optionally configuring based on
Devicetree instead of ACPI, use a more generic platform device to reduce
the dependency on ACPI where possible, though the dependency on ACPI
is not completely removed.  Also rename the function vmbus_acpi_remove()
to the more generic vmbus_mmio_remove().

Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1679298460-11855-4-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index d24dd65..7349715 100644 (file)
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -12,6 +12,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/device.h>
+#include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/sysctl.h>
 #include <linux/slab.h>
@@ -44,7 +45,7 @@ struct vmbus_dynid {
        struct hv_vmbus_device_id id;
 };
 
-static struct acpi_device  *hv_acpi_dev;
+static struct device  *hv_dev;
 
 static int hyperv_cpuhp_online;
 
@@ -143,7 +144,7 @@ static DEFINE_MUTEX(hyperv_mmio_lock);
 
 static int vmbus_exists(void)
 {
-       if (hv_acpi_dev == NULL)
+       if (hv_dev == NULL)
                return -ENODEV;
 
        return 0;
@@ -932,7 +933,7 @@ static int vmbus_dma_configure(struct device *child_device)
         * On x86/x64 coherence is assumed and these calls have no effect.
         */
        hv_setup_dma_ops(child_device,
-               device_get_dma_attr(&hv_acpi_dev->dev) == DEV_DMA_COHERENT);
+               device_get_dma_attr(hv_dev) == DEV_DMA_COHERENT);
        return 0;
 }
 
@@ -2090,7 +2091,7 @@ int vmbus_device_register(struct hv_device *child_device_obj)
                     &child_device_obj->channel->offermsg.offer.if_instance);
 
        child_device_obj->device.bus = &hv_bus;
-       child_device_obj->device.parent = &hv_acpi_dev->dev;
+       child_device_obj->device.parent = hv_dev;
        child_device_obj->device.release = vmbus_device_release;
 
        child_device_obj->device.dma_parms = &child_device_obj->dma_parms;
@@ -2262,7 +2263,7 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
        return AE_OK;
 }
 
-static void vmbus_acpi_remove(struct acpi_device *device)
+static void vmbus_mmio_remove(void)
 {
        struct resource *cur_res;
        struct resource *next_res;
@@ -2441,13 +2442,14 @@ void vmbus_free_mmio(resource_size_t start, resource_size_t size)
 }
 EXPORT_SYMBOL_GPL(vmbus_free_mmio);
 
-static int vmbus_acpi_add(struct acpi_device *device)
+static int vmbus_acpi_add(struct platform_device *pdev)
 {
        acpi_status result;
        int ret_val = -ENODEV;
        struct acpi_device *ancestor;
+       struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
 
-       hv_acpi_dev = device;
+       hv_dev = &device->dev;
 
        /*
         * Older versions of Hyper-V for ARM64 fail to include the _CCA
@@ -2489,10 +2491,21 @@ static int vmbus_acpi_add(struct acpi_device *device)
 
 acpi_walk_err:
        if (ret_val)
-               vmbus_acpi_remove(device);
+               vmbus_mmio_remove();
        return ret_val;
 }
 
+static int vmbus_platform_driver_probe(struct platform_device *pdev)
+{
+       return vmbus_acpi_add(pdev);
+}
+
+static int vmbus_platform_driver_remove(struct platform_device *pdev)
+{
+       vmbus_mmio_remove();
+       return 0;
+}
+
 #ifdef CONFIG_PM_SLEEP
 static int vmbus_bus_suspend(struct device *dev)
 {
@@ -2658,15 +2671,15 @@ static const struct dev_pm_ops vmbus_bus_pm = {
        .restore_noirq  = vmbus_bus_resume
 };
 
-static struct acpi_driver vmbus_acpi_driver = {
-       .name = "vmbus",
-       .ids = vmbus_acpi_device_ids,
-       .ops = {
-               .add = vmbus_acpi_add,
-               .remove = vmbus_acpi_remove,
-       },
-       .drv.pm = &vmbus_bus_pm,
-       .drv.probe_type = PROBE_FORCE_SYNCHRONOUS,
+static struct platform_driver vmbus_platform_driver = {
+       .probe = vmbus_platform_driver_probe,
+       .remove = vmbus_platform_driver_remove,
+       .driver = {
+               .name = "vmbus",
+               .acpi_match_table = ACPI_PTR(vmbus_acpi_device_ids),
+               .pm = &vmbus_bus_pm,
+               .probe_type = PROBE_FORCE_SYNCHRONOUS,
+       }
 };
 
 static void hv_kexec_handler(void)
@@ -2750,12 +2763,11 @@ static int __init hv_acpi_init(void)
        /*
         * Get ACPI resources first.
         */
-       ret = acpi_bus_register_driver(&vmbus_acpi_driver);
-
+       ret = platform_driver_register(&vmbus_platform_driver);
        if (ret)
                return ret;
 
-       if (!hv_acpi_dev) {
+       if (!hv_dev) {
                ret = -ENODEV;
                goto cleanup;
        }
@@ -2785,8 +2797,8 @@ static int __init hv_acpi_init(void)
        return 0;
 
 cleanup:
-       acpi_bus_unregister_driver(&vmbus_acpi_driver);
-       hv_acpi_dev = NULL;
+       platform_driver_unregister(&vmbus_platform_driver);
+       hv_dev = NULL;
        return ret;
 }
 
@@ -2839,7 +2851,7 @@ static void __exit vmbus_exit(void)
 
        cpuhp_remove_state(hyperv_cpuhp_online);
        hv_synic_free();
-       acpi_bus_unregister_driver(&vmbus_acpi_driver);
+       platform_driver_unregister(&vmbus_platform_driver);
 }