linux-kernel - [PATCH v9 5/6] pwm: dwc: round rate divisions up

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <20230907161242.67190-6-ben.dooks@codethink.co.uk>
Date:   Thu,  7 Sep 2023 17:12:41 +0100
From:   Ben Dooks <ben.dooks@...ethink.co.uk>
To:     linux-pwm@...r.kernel.org
Cc:     devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        ben.dooks@...ethink.co.uk, u.kleine-koenig@...gutronix.de,
        Thierry Reding <thierry.reding@...il.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Greentime Hu <greentime.hu@...ive.com>,
        jarkko.nikula@...ux.intel.com,
        William Salmon <william.salmon@...ive.com>,
        Jude Onyenegecha <jude.onyenegecha@...ive.com>
Subject: [PATCH v9 5/6] pwm: dwc: round rate divisions up

As suggested, round up the counter variables to ensure we
always produce a longer period calculation.

Reported-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
Signed-off-by: Ben Dooks <ben.dooks@...ethink.co.uk>
---
 drivers/pwm/pwm-dwc-core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pwm/pwm-dwc-core.c b/drivers/pwm/pwm-dwc-core.c
index 3b856685029d..6358e3345210 100644
--- a/drivers/pwm/pwm-dwc-core.c
+++ b/drivers/pwm/pwm-dwc-core.c
@@ -50,13 +50,13 @@ static int __dwc_pwm_configure_timer(struct dwc_pwm *dwc,
 	 * 2^32 periods.
 	 */
 	tmp = state->duty_cycle * dwc->clk_rate;
-	tmp = DIV_ROUND_CLOSEST_ULL(tmp, NSEC_PER_SEC);
+	tmp = DIV_ROUND_UP_ULL(tmp, NSEC_PER_SEC);
 	if (tmp < 1 || tmp > (1ULL << 32))
 		return -ERANGE;
 	low = tmp - 1;
 
 	tmp = (state->period - state->duty_cycle) * dwc->clk_rate;
-	tmp = DIV_ROUND_CLOSEST_ULL(tmp, NSEC_PER_SEC);
+	tmp = DIV_ROUND_UP_ULL(tmp, NSEC_PER_SEC);
 	if (tmp < 1 || tmp > (1ULL << 32))
 		return -ERANGE;
 	high = tmp - 1;
-- 
2.40.1