All of lore.kernel.org
 help / color / mirror / Atom feed
From: Baruch Siach <baruch@tkos.co.il>
To: "Thierry Reding" <thierry.reding@gmail.com>,
	"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>,
	"Lee Jones" <lee.jones@linaro.org>,
	"Linus Walleij" <linus.walleij@linaro.org>,
	"Bartosz Golaszewski" <bgolaszewski@baylibre.com>
Cc: Baruch Siach <baruch@tkos.co.il>, Andrew Lunn <andrew@lunn.ch>,
	Gregory Clement <gregory.clement@bootlin.com>,
	Russell King <linux@armlinux.org.uk>,
	Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	Chris Packham <chris.packham@alliedtelesis.co.nz>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Ralph Sennhauser <ralph.sennhauser@gmail.com>,
	linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH 4/5] gpio: mvebu: don't limit pwm period/duty_cycle to UINT_MAX
Date: Mon, 11 Jan 2021 13:17:05 +0200	[thread overview]
Message-ID: <97e5ed4dfc4385a99c585f7980210f9dd7c6ee3d.1610362661.git.baruch@tkos.co.il> (raw)
In-Reply-To: <cover.1610362661.git.baruch@tkos.co.il>

PWM on/off registers are limited to UINT_MAX. However the state period
and duty_cycle fields are ns values of type u64. There is no reason to
limit them to UINT_MAX.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
 drivers/gpio/gpio-mvebu.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index 6fc64846eda3..eb7456fa6d86 100644
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c
@@ -669,9 +669,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
 	regmap_read(mvpwm->regs, mvebu_pwmreg_blink_on_duration(mvpwm), &u);
 	val = (unsigned long long) u * NSEC_PER_SEC;
 	val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate);
-	if (val > UINT_MAX)
-		state->duty_cycle = UINT_MAX;
-	else if (val)
+	if (val)
 		state->duty_cycle = val;
 	else
 		state->duty_cycle = 1;
@@ -681,9 +679,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
 	val += (unsigned long long) u; /* period = on + off duration */
 	val *= NSEC_PER_SEC;
 	val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate);
-	if (val > UINT_MAX)
-		state->period = UINT_MAX;
-	else if (val)
+	if (val)
 		state->period = val;
 	else
 		state->period = 1;
-- 
2.29.2


WARNING: multiple messages have this Message-ID (diff)
From: Baruch Siach <baruch@tkos.co.il>
To: "Thierry Reding" <thierry.reding@gmail.com>,
	"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>,
	"Lee Jones" <lee.jones@linaro.org>,
	"Linus Walleij" <linus.walleij@linaro.org>,
	"Bartosz Golaszewski" <bgolaszewski@baylibre.com>
Cc: Andrew Lunn <andrew@lunn.ch>, Baruch Siach <baruch@tkos.co.il>,
	linux-pwm@vger.kernel.org,
	Gregory Clement <gregory.clement@bootlin.com>,
	Russell King <linux@armlinux.org.uk>,
	linux-gpio@vger.kernel.org,
	Chris Packham <chris.packham@alliedtelesis.co.nz>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	Ralph Sennhauser <ralph.sennhauser@gmail.com>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	linux-arm-kernel@lists.infradead.org,
	Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Subject: [PATCH 4/5] gpio: mvebu: don't limit pwm period/duty_cycle to UINT_MAX
Date: Mon, 11 Jan 2021 13:17:05 +0200	[thread overview]
Message-ID: <97e5ed4dfc4385a99c585f7980210f9dd7c6ee3d.1610362661.git.baruch@tkos.co.il> (raw)
In-Reply-To: <cover.1610362661.git.baruch@tkos.co.il>

PWM on/off registers are limited to UINT_MAX. However the state period
and duty_cycle fields are ns values of type u64. There is no reason to
limit them to UINT_MAX.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
 drivers/gpio/gpio-mvebu.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index 6fc64846eda3..eb7456fa6d86 100644
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c
@@ -669,9 +669,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
 	regmap_read(mvpwm->regs, mvebu_pwmreg_blink_on_duration(mvpwm), &u);
 	val = (unsigned long long) u * NSEC_PER_SEC;
 	val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate);
-	if (val > UINT_MAX)
-		state->duty_cycle = UINT_MAX;
-	else if (val)
+	if (val)
 		state->duty_cycle = val;
 	else
 		state->duty_cycle = 1;
@@ -681,9 +679,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip,
 	val += (unsigned long long) u; /* period = on + off duration */
 	val *= NSEC_PER_SEC;
 	val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate);
-	if (val > UINT_MAX)
-		state->period = UINT_MAX;
-	else if (val)
+	if (val)
 		state->period = val;
 	else
 		state->period = 1;
-- 
2.29.2


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2021-01-11 11:18 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-01-11 11:17 [PATCH 0/5] gpio: mvebu: pwm fixes and improvements Baruch Siach
2021-01-11 11:17 ` Baruch Siach
2021-01-11 11:17 ` [PATCH 1/5] gpio: mvebu: fix pwm get_state period calculation Baruch Siach
2021-01-11 11:17   ` Baruch Siach
2021-01-11 20:17   ` Uwe Kleine-König
2021-01-11 20:17     ` Uwe Kleine-König
2021-01-13  6:36     ` Baruch Siach
2021-01-13  6:36       ` Baruch Siach
2021-01-13  8:17       ` Uwe Kleine-König
2021-01-13  8:17         ` Uwe Kleine-König
2021-01-11 11:17 ` [PATCH 2/5] gpio: mvebu: improve pwm period calculation accuracy Baruch Siach
2021-01-11 11:17   ` Baruch Siach
2021-01-11 20:18   ` Uwe Kleine-König
2021-01-11 20:18     ` Uwe Kleine-König
2021-01-11 11:17 ` [PATCH 3/5] gpio: mvebu: make pwm apply/get_state closer to idempotent Baruch Siach
2021-01-11 11:17   ` Baruch Siach
2021-01-11 20:20   ` Uwe Kleine-König
2021-01-11 20:20     ` Uwe Kleine-König
2021-01-11 11:17 ` Baruch Siach [this message]
2021-01-11 11:17   ` [PATCH 4/5] gpio: mvebu: don't limit pwm period/duty_cycle to UINT_MAX Baruch Siach
2021-01-11 20:21   ` Uwe Kleine-König
2021-01-11 20:21     ` Uwe Kleine-König
2021-01-11 11:17 ` [PATCH 5/5] gpio: mvebu: document zero pwm duty cycle limitation Baruch Siach
2021-01-11 11:17   ` Baruch Siach
2021-01-11 20:24   ` Uwe Kleine-König
2021-01-11 20:24     ` Uwe Kleine-König
2021-01-11 22:43     ` Russell King - ARM Linux admin
2021-01-11 22:43       ` Russell King - ARM Linux admin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=97e5ed4dfc4385a99c585f7980210f9dd7c6ee3d.1610362661.git.baruch@tkos.co.il \
    --to=baruch@tkos.co.il \
    --cc=andrew@lunn.ch \
    --cc=bgolaszewski@baylibre.com \
    --cc=chris.packham@alliedtelesis.co.nz \
    --cc=gregory.clement@bootlin.com \
    --cc=lee.jones@linaro.org \
    --cc=linus.walleij@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-gpio@vger.kernel.org \
    --cc=linux-pwm@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=ralph.sennhauser@gmail.com \
    --cc=s.hauer@pengutronix.de \
    --cc=sebastian.hesselbarth@gmail.com \
    --cc=thierry.reding@gmail.com \
    --cc=thomas.petazzoni@bootlin.com \
    --cc=u.kleine-koenig@pengutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.