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From: Roman Beranek <roman.beranek@prusa3d.cz>
To: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
Cc: Thierry Reding <thierry.reding@gmail.com>,
	Emil Lenngren <emil.lenngren@gmail.com>,
	Pascal Roeleven <dev@pascalroeleven.nl>,
	Lee Jones <lee.jones@linaro.org>,
	Maxime Ripard <mripard@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
	linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-sunxi@lists.linux.dev, linux-sunxi@googlegroups.com
Subject: [PATCH 1/6] pwm: sun4i: enable clk prior to getting its rate
Date: Mon, 31 May 2021 06:46:03 +0200	[thread overview]
Message-ID: <20210531044608.1006024-2-roman.beranek@prusa3d.com> (raw)
In-Reply-To: <20210531044608.1006024-1-roman.beranek@prusa3d.com>

Ensure the PWM clock is enabled prior to retrieving its rate, as is
already being done in sun4i_pwm_apply.

Signed-off-by: Roman Beranek <roman.beranek@prusa3d.com>
---
 drivers/pwm/pwm-sun4i.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c
index e01becd102c0..3721b9894cf6 100644
--- a/drivers/pwm/pwm-sun4i.c
+++ b/drivers/pwm/pwm-sun4i.c
@@ -117,8 +117,15 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip,
 	u64 clk_rate, tmp;
 	u32 val;
 	unsigned int prescaler;
+	int ret;
 
+	ret = clk_prepare_enable(sun4i_pwm->clk);
+	if (ret) {
+		dev_err(chip->dev, "failed to enable PWM clock\n");
+		return;
+	}
 	clk_rate = clk_get_rate(sun4i_pwm->clk);
+	clk_disable_unprepare(sun4i_pwm->clk);
 
 	val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG);
 
-- 
2.31.1


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  reply	other threads:[~2021-05-31  4:47 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-31  4:46 [PATCH 0/6] pwm: sun4i: only wait 2 cycles prior to disabling Roman Beranek
2021-05-31  4:46 ` Roman Beranek [this message]
2021-06-07  8:00   ` [PATCH 1/6] pwm: sun4i: enable clk prior to getting its rate Uwe Kleine-König
2021-05-31  4:46 ` [PATCH 2/6] pwm: sun4i: disable EN bit prior to the delay Roman Beranek
2021-06-07  8:07   ` Uwe Kleine-König
2021-05-31  4:46 ` [PATCH 3/6] pwm: sun4i: replace spinlock with a mutex Roman Beranek
2021-05-31  4:46 ` [PATCH 4/6] pwm: sun4i: simplify calculation of the delay time Roman Beranek
2021-05-31  4:46 ` [PATCH 5/6] pwm: sun4i: shorten the delay to 2 cycles Roman Beranek
2021-05-31  4:46 ` [PATCH 6/6] pwm: sun4i: don't delay if the PWM is already off Roman Beranek
2021-06-10 13:41   ` Pascal Roeleven
2021-05-31 19:07 ` [PATCH 0/6] pwm: sun4i: only wait 2 cycles prior to disabling Pascal Roeleven
2021-05-31 20:01   ` Emil Lenngren
2021-05-31 20:20     ` Pascal Roeleven
2021-06-08 12:28   ` Pascal Roeleven

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