[RFC PATCH v1 23/38] coco: guest: arm64: Update arm CCA guest driver

["Aneesh Kumar K.V (Arm)" <aneesh.kumar@kernel.org>]

This patch includes renaming changes to simplify the registration of a
TSM backend in the next patch. There are no functional changes in this
update.

Signed-off-by: Aneesh Kumar K.V (Arm) <aneesh.kumar@kernel.org>
---
 arch/arm64/include/asm/rsi.h                  |  2 +-
 arch/arm64/kernel/rsi.c                       |  2 +-
 drivers/virt/coco/arm-cca-guest/Makefile      |  3 ++
 .../{arm-cca-guest.c => arm-cca.c}            | 52 +++++++++----------
 4 files changed, 29 insertions(+), 30 deletions(-)
 rename drivers/virt/coco/arm-cca-guest/{arm-cca-guest.c => arm-cca.c} (86%)

diff --git a/arch/arm64/include/asm/rsi.h b/arch/arm64/include/asm/rsi.h
index b42aeac05340..26ef6143562b 100644
--- a/arch/arm64/include/asm/rsi.h
+++ b/arch/arm64/include/asm/rsi.h
@@ -10,7 +10,7 @@
 #include <linux/jump_label.h>
 #include <asm/rsi_cmds.h>
 
-#define RSI_PDEV_NAME "arm-cca-dev"
+#define RSI_DEV_NAME "arm-rsi-dev"
 
 DECLARE_STATIC_KEY_FALSE(rsi_present);
 
diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c
index ce4778141ec7..bf9ea99e2aa1 100644
--- a/arch/arm64/kernel/rsi.c
+++ b/arch/arm64/kernel/rsi.c
@@ -142,7 +142,7 @@ void __init arm64_rsi_init(void)
 }
 
 static struct platform_device rsi_dev = {
-	.name = RSI_PDEV_NAME,
+	.name = RSI_DEV_NAME,
 	.id = PLATFORM_DEVID_NONE
 };
 
diff --git a/drivers/virt/coco/arm-cca-guest/Makefile b/drivers/virt/coco/arm-cca-guest/Makefile
index 69eeba08e98a..609462ea9438 100644
--- a/drivers/virt/coco/arm-cca-guest/Makefile
+++ b/drivers/virt/coco/arm-cca-guest/Makefile
@@ -1,2 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
+#
 obj-$(CONFIG_ARM_CCA_GUEST) += arm-cca-guest.o
+
+arm-cca-guest-$(CONFIG_TSM) +=  arm-cca.o
diff --git a/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c b/drivers/virt/coco/arm-cca-guest/arm-cca.c
similarity index 86%
rename from drivers/virt/coco/arm-cca-guest/arm-cca-guest.c
rename to drivers/virt/coco/arm-cca-guest/arm-cca.c
index 0c9ea24a200c..547fc2c79f7d 100644
--- a/drivers/virt/coco/arm-cca-guest/arm-cca-guest.c
+++ b/drivers/virt/coco/arm-cca-guest/arm-cca.c
@@ -11,6 +11,7 @@
 #include <linux/smp.h>
 #include <linux/tsm.h>
 #include <linux/types.h>
+#include <linux/platform_device.h>
 
 #include <asm/rsi.h>
 
@@ -181,52 +182,47 @@ static int arm_cca_report_new(struct tsm_report *report, void *data)
 	return ret;
 }
 
-static const struct tsm_report_ops arm_cca_tsm_ops = {
+static const struct tsm_report_ops arm_cca_tsm_report_ops = {
 	.name = KBUILD_MODNAME,
 	.report_new = arm_cca_report_new,
 };
 
-/**
- * arm_cca_guest_init - Register with the Trusted Security Module (TSM)
- * interface.
- *
- * Return:
- * * %0        - Registered successfully with the TSM interface.
- * * %-ENODEV  - The execution context is not an Arm Realm.
- * * %-EBUSY   - Already registered.
- */
-static int __init arm_cca_guest_init(void)
+static void unregister_cca_tsm_report(void *data)
+{
+	tsm_report_unregister(&arm_cca_tsm_report_ops);
+}
+
+static int cca_guest_probe(struct platform_device *pdev)
 {
 	int ret;
 
 	if (!is_realm_world())
 		return -ENODEV;
 
-	ret = tsm_report_register(&arm_cca_tsm_ops, NULL);
+	ret = tsm_report_register(&arm_cca_tsm_report_ops, NULL);
 	if (ret < 0)
 		pr_err("Error %d registering with TSM\n", ret);
 
-	return ret;
-}
-module_init(arm_cca_guest_init);
+	ret = devm_add_action_or_reset(&pdev->dev, unregister_cca_tsm_report, NULL);
 
-/**
- * arm_cca_guest_exit - unregister with the Trusted Security Module (TSM)
- * interface.
- */
-static void __exit arm_cca_guest_exit(void)
-{
-	tsm_report_unregister(&arm_cca_tsm_ops);
+	return ret;
 }
-module_exit(arm_cca_guest_exit);
 
 /* modalias, so userspace can autoload this module when RSI is available */
-static const struct platform_device_id arm_cca_match[] __maybe_unused = {
-	{ RSI_PDEV_NAME, 0},
+static const struct platform_device_id arm_cca_guest_id_table[] = {
+	{ RSI_DEV_NAME, 0},
 	{ }
 };
-
-MODULE_DEVICE_TABLE(platform, arm_cca_match);
+MODULE_DEVICE_TABLE(platform, arm_cca_guest_id_table);
+
+static struct platform_driver cca_guest_platform_driver = {
+	.probe = cca_guest_probe,
+	.id_table = arm_cca_guest_id_table,
+	.driver = {
+		.name = "arm-cca-guest",
+	},
+};
+module_platform_driver(cca_guest_platform_driver);
 MODULE_AUTHOR("Sami Mujawar <sami.mujawar@arm.com>");
-MODULE_DESCRIPTION("Arm CCA Guest TSM Driver");
+MODULE_DESCRIPTION("Arm CCA Guest TSM driver");
 MODULE_LICENSE("GPL");
-- 
2.43.0