iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted

isl29501_register_write() was returning a u32 instead of an int.
Since the function returns negative error codes (such as -ERANGE or
return values from i2c_smbus_write_byte_data()), returning an unsigned
integer type prevents callers from correctly checking for negative error
conditions.

Fix this by changing the function return type from u32 to int.

This was found through manual code review.

Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

1 files changed, 140 insertions, 0 deletions

diff --git a/crypto/kpp.c b/crypto/kpp.c
new file mode 100644
index 000000000..522c352a0
--- /dev/null
+++ b/crypto/kpp.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Key-agreement Protocol Primitives (KPP)
+ *
+ * Copyright (c) 2016, Intel Corporation
+ * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com>
+ */
+
+#include <crypto/internal/kpp.h>
+#include <linux/cryptouser.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <net/netlink.h>
+
+#include "internal.h"
+
+static int __maybe_unused crypto_kpp_report(
+	struct sk_buff *skb, struct crypto_alg *alg)
+{
+	struct crypto_report_kpp rkpp = {
+		.type = "kpp",
+	};
+
+	return nla_put(skb, CRYPTOCFGA_REPORT_KPP, sizeof(rkpp), &rkpp);
+}
+
+static void __maybe_unused crypto_kpp_show(struct seq_file *m,
+					   struct crypto_alg *alg)
+{
+	seq_puts(m, "type         : kpp\n");
+}
+
+static void crypto_kpp_exit_tfm(struct crypto_tfm *tfm)
+{
+	struct crypto_kpp *kpp = __crypto_kpp_tfm(tfm);
+	struct kpp_alg *alg = crypto_kpp_alg(kpp);
+
+	alg->exit(kpp);
+}
+
+static int crypto_kpp_init_tfm(struct crypto_tfm *tfm)
+{
+	struct crypto_kpp *kpp = __crypto_kpp_tfm(tfm);
+	struct kpp_alg *alg = crypto_kpp_alg(kpp);
+
+	if (alg->exit)
+		kpp->base.exit = crypto_kpp_exit_tfm;
+
+	if (alg->init)
+		return alg->init(kpp);
+
+	return 0;
+}
+
+static void crypto_kpp_free_instance(struct crypto_instance *inst)
+{
+	struct kpp_instance *kpp = kpp_instance(inst);
+
+	kpp->free(kpp);
+}
+
+static const struct crypto_type crypto_kpp_type = {
+	.extsize = crypto_alg_extsize,
+	.init_tfm = crypto_kpp_init_tfm,
+	.free = crypto_kpp_free_instance,
+#ifdef CONFIG_PROC_FS
+	.show = crypto_kpp_show,
+#endif
+#if IS_ENABLED(CONFIG_CRYPTO_USER)
+	.report = crypto_kpp_report,
+#endif
+	.maskclear = ~CRYPTO_ALG_TYPE_MASK,
+	.maskset = CRYPTO_ALG_TYPE_MASK,
+	.type = CRYPTO_ALG_TYPE_KPP,
+	.tfmsize = offsetof(struct crypto_kpp, base),
+	.algsize = offsetof(struct kpp_alg, base),
+};
+
+struct crypto_kpp *crypto_alloc_kpp(const char *alg_name, u32 type, u32 mask)
+{
+	return crypto_alloc_tfm(alg_name, &crypto_kpp_type, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_alloc_kpp);
+
+int crypto_grab_kpp(struct crypto_kpp_spawn *spawn,
+		    struct crypto_instance *inst,
+		    const char *name, u32 type, u32 mask)
+{
+	spawn->base.frontend = &crypto_kpp_type;
+	return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_grab_kpp);
+
+int crypto_has_kpp(const char *alg_name, u32 type, u32 mask)
+{
+	return crypto_type_has_alg(alg_name, &crypto_kpp_type, type, mask);
+}
+EXPORT_SYMBOL_GPL(crypto_has_kpp);
+
+static void kpp_prepare_alg(struct kpp_alg *alg)
+{
+	struct crypto_alg *base = &alg->base;
+
+	base->cra_type = &crypto_kpp_type;
+	base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
+	base->cra_flags |= CRYPTO_ALG_TYPE_KPP;
+}
+
+int crypto_register_kpp(struct kpp_alg *alg)
+{
+	struct crypto_alg *base = &alg->base;
+
+	kpp_prepare_alg(alg);
+	return crypto_register_alg(base);
+}
+EXPORT_SYMBOL_GPL(crypto_register_kpp);
+
+void crypto_unregister_kpp(struct kpp_alg *alg)
+{
+	crypto_unregister_alg(&alg->base);
+}
+EXPORT_SYMBOL_GPL(crypto_unregister_kpp);
+
+int kpp_register_instance(struct crypto_template *tmpl,
+			  struct kpp_instance *inst)
+{
+	if (WARN_ON(!inst->free))
+		return -EINVAL;
+
+	kpp_prepare_alg(&inst->alg);
+
+	return crypto_register_instance(tmpl, kpp_crypto_instance(inst));
+}
+EXPORT_SYMBOL_GPL(kpp_register_instance);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Key-agreement Protocol Primitives");