@@ -16,9 +16,11 @@
#include <linux/device.h>
#include <linux/hw_random.h>
#include <linux/module.h>
-#include <linux/platform_device.h>
+#include <linux/device/faux.h>
#include <linux/arm-smccc.h>
+#include <asm/archrandom.h>
+
#ifdef CONFIG_ARM64
#define ARM_SMCCC_TRNG_RND ARM_SMCCC_TRNG_RND64
#define MAX_BITS_PER_CALL (3 * 64UL)
@@ -94,29 +96,22 @@ static int smccc_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
return copied;
}
-static int smccc_trng_probe(struct platform_device *pdev)
+static int smccc_trng_probe(struct faux_device *fdev)
{
struct hwrng *trng;
- trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
+ trng = devm_kzalloc(&fdev->dev, sizeof(*trng), GFP_KERNEL);
if (!trng)
return -ENOMEM;
trng->name = "smccc_trng";
trng->read = smccc_trng_read;
- return devm_hwrng_register(&pdev->dev, trng);
+ return devm_hwrng_register(&fdev->dev, trng);
}
-static struct platform_driver smccc_trng_driver = {
- .driver = {
- .name = "smccc_trng",
- },
- .probe = smccc_trng_probe,
-};
-module_platform_driver(smccc_trng_driver);
+module_faux_driver(smccc_trng, smccc_trng_probe, NULL, smccc_trng_available);
-MODULE_ALIAS("platform:smccc_trng");
MODULE_AUTHOR("Andre Przywara");
MODULE_DESCRIPTION("Arm SMCCC TRNG firmware interface support");
MODULE_LICENSE("GPL");
@@ -9,7 +9,6 @@
#include <linux/init.h>
#include <linux/arm-smccc.h>
#include <linux/kernel.h>
-#include <linux/platform_device.h>
#include <asm/archrandom.h>
static u32 smccc_version = ARM_SMCCC_VERSION_1_0;
@@ -66,19 +65,3 @@ s32 arm_smccc_get_soc_id_revision(void)
return smccc_soc_id_revision;
}
EXPORT_SYMBOL_GPL(arm_smccc_get_soc_id_revision);
-
-static int __init smccc_devices_init(void)
-{
- struct platform_device *pdev;
-
- if (smccc_trng_available) {
- pdev = platform_device_register_simple("smccc_trng", -1,
- NULL, 0);
- if (IS_ERR(pdev))
- pr_err("smccc_trng: could not register device: %ld\n",
- PTR_ERR(pdev));
- }
-
- return 0;
-}
-device_initcall(smccc_devices_init);
The Arm SMCCC based true random number generator driver does not require the creation of a platform device/driver. Originally, this approach was chosen for simplicity when the driver was first implemented. With the introduction of the lightweight faux device interface, we now have a more appropriate alternative. Migrate the driver to utilize the faux bus, given that the platform device it previously created was not a real one anyway. This will simplify the code, reducing its footprint while maintaining functionality. Cc: Andre Przywara <andre.przywara@arm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jeff Johnson <jeff.johnson@oss.qualcomm.com> Cc: linux-crypto@vger.kernel.org Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> --- drivers/char/hw_random/arm_smccc_trng.c | 19 +++++++------------ drivers/firmware/smccc/smccc.c | 17 ----------------- 2 files changed, 7 insertions(+), 29 deletions(-)