linux-kernel - [PATCH 2/2] pwm: renesas-tpu: don't allow no duty if duty

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210915065542.1897-3-wsa+renesas@sang-engineering.com>
Date:   Wed, 15 Sep 2021 08:55:41 +0200
From:   Wolfram Sang <wsa+renesas@...g-engineering.com>
To:     linux-pwm@...r.kernel.org
Cc:     linux-renesas-soc@...r.kernel.org,
        Duc Nguyen <duc.nguyen.ub@...esas.com>,
        Wolfram Sang <wsa+renesas@...g-engineering.com>,
        Thierry Reding <thierry.reding@...il.com>,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>, Lee Jones <lee.jones@...aro.org>,
        linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] pwm: renesas-tpu: don't allow no duty if duty_ns is given

From: Duc Nguyen <duc.nguyen.ub@...esas.com>

We have special code if duty_ns is 0. But if non-zero is given, then the
calculation should not result in zero duty.

Signed-off-by: Duc Nguyen <duc.nguyen.ub@...esas.com>
[wsa: split and reworded commit message]
Signed-off-by: Wolfram Sang <wsa+renesas@...g-engineering.com>
---
 drivers/pwm/pwm-renesas-tpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-renesas-tpu.c b/drivers/pwm/pwm-renesas-tpu.c
index 754440194650..bb51156e4bda 100644
--- a/drivers/pwm/pwm-renesas-tpu.c
+++ b/drivers/pwm/pwm-renesas-tpu.c
@@ -275,7 +275,7 @@ static int tpu_pwm_config(struct pwm_chip *chip, struct pwm_device *_pwm,
 	if (duty_ns) {
 		duty = clk_rate / prescalers[prescaler]
 		     / (NSEC_PER_SEC / duty_ns);
-		if (duty > period)
+		if (duty > period || duty == 0)
 			return -EINVAL;
 	} else {
 		duty = 0;
-- 
2.30.2