linux-kernel - [PATCH 15/44] drivers/char/tpm: use min() instead of min

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Message-Id: <20251119224140.8616-16-david.laight.linux@gmail.com>
Date: Wed, 19 Nov 2025 22:41:11 +0000
From: david.laight.linux@...il.com
To: linux-kernel@...r.kernel.org,
	linux-integrity@...r.kernel.org
Cc: Jarkko Sakkinen <jarkko@...nel.org>,
	Peter Huewe <peterhuewe@....de>,
	David Laight <david.laight.linux@...il.com>
Subject: [PATCH 15/44] drivers/char/tpm: use min() instead of min_t()

From: David Laight <david.laight.linux@...il.com>

min_t(int, a, b) casts an 'long' to 'int'.
Use min(a, b) instead as it promotes any 'int' to 'long'
and so cannot discard significant bits.

In this case the 'long' value is small enough that the result is ok.

Detected by an extra check added to min_t().

Signed-off-by: David Laight <david.laight.linux@...il.com>
---
 drivers/char/tpm/tpm1-cmd.c     | 2 +-
 drivers/char/tpm/tpm_tis_core.c | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index cf64c7385105..11088bda4e68 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -530,7 +530,7 @@ struct tpm1_get_random_out {
 int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
 {
 	struct tpm1_get_random_out *out;
-	u32 num_bytes =  min_t(u32, max, TPM_MAX_RNG_DATA);
+	u32 num_bytes =  min(max, TPM_MAX_RNG_DATA);
 	struct tpm_buf buf;
 	u32 total = 0;
 	int retries = 5;
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 8954a8660ffc..2676e3a241b5 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -310,7 +310,7 @@ static int get_burstcount(struct tpm_chip *chip)
 	return -EBUSY;
 }
 
-static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
+static int recv_data(struct tpm_chip *chip, u8 *buf, u32 count)
 {
 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 	int size = 0, burstcnt, rc;
@@ -453,7 +453,7 @@ static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
 			rc = burstcnt;
 			goto out_err;
 		}
-		burstcnt = min_t(int, burstcnt, len - count - 1);
+		burstcnt = min(burstcnt, len - count - 1);
 		rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
 					 burstcnt, buf + count);
 		if (rc < 0)
-- 
2.39.5