linux-kernel - Re: [PATCH v3] pwm: atmel: Enable clk when pwm already enabled in bootloader

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Message-ID: <20230711203017.cdfe2nrjx7lt25tm@pengutronix.de>
Date:   Tue, 11 Jul 2023 22:30:17 +0200
From:   Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
To:     Guiting Shen <aarongt.shen@...il.com>
Cc:     claudiu.beznea@...rochip.com, thierry.reding@...il.com,
        nicolas.ferre@...rochip.com, alexandre.belloni@...tlin.com,
        linux-arm-kernel@...ts.infradead.org, linux-pwm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3] pwm: atmel: Enable clk when pwm already enabled in
 bootloader

Hello,

On Wed, Jul 12, 2023 at 04:09:05AM +0800, Guiting Shen wrote:
> +static int atmel_pwm_enable_clk_if_on(struct atmel_pwm_chip *atmel_pwm)
> +{
> +	unsigned int i;
> +	int err;
> +	u32 sr;
> +
> +	sr = atmel_pwm_readl(atmel_pwm, PWM_SR);
> +	if (!sr)
> +		return 0;
> +
> +	for (i = 0; i < atmel_pwm->chip.npwm; i++) {
> +		if (!(sr & (1 << i)))
> +			continue;
> +
> +		err = clk_enable(atmel_pwm->clk);
> +		if (err) {
> +			dev_err(atmel_pwm->chip.dev,
> +				"failed to enable clock: %pe\n", ERR_PTR(err));

Here you leak possibly a few enables. While it's not likely that the
(say) third enable goes wrong, it's also not that hard to handle?!

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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