linux-kernel - Re: [PATCH v3] media: rc: pwm-ir-tx: Switch to atomic PWM API

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Message-ID: <20211025060812.pqwapyqni4vx75tc@pengutronix.de>
Date:   Mon, 25 Oct 2021 08:08:12 +0200
From:   Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
To:     Maíra Canal <maira.canal@....br>
Cc:     sean@...s.org, mchehab@...nel.org, thierry.reding@...il.com,
        lee.jones@...aro.org, linux-media@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-pwm@...r.kernel.org
Subject: Re: [PATCH v3] media: rc: pwm-ir-tx: Switch to atomic PWM API

Hello,

On Sun, Oct 24, 2021 at 07:33:47AM -0300, Maíra Canal wrote:
> Remove legacy PWM interface (pwm_config, pwm_enable, pwm_disable) and
> replace it for the atomic PWM API.
> 
> Signed-off-by: Maíra Canal <maira.canal@....br>
> ---
> V1 -> V2: Assign variables directly and simplify conditional statement
> V2 -> V3: Fix declaration of undeclared variable
> ---
>  drivers/media/rc/pwm-ir-tx.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/media/rc/pwm-ir-tx.c b/drivers/media/rc/pwm-ir-tx.c
> index 4bc28d2c9cc9..e1f348a962e8 100644
> --- a/drivers/media/rc/pwm-ir-tx.c
> +++ b/drivers/media/rc/pwm-ir-tx.c
> @@ -53,22 +53,21 @@ static int pwm_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
>  {
>  	struct pwm_ir *pwm_ir = dev->priv;
>  	struct pwm_device *pwm = pwm_ir->pwm;
> -	int i, duty, period;
> +	struct pwm_state state;
> +	int i;
>  	ktime_t edge;
>  	long delta;
>  
> -	period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier);
> -	duty = DIV_ROUND_CLOSEST(pwm_ir->duty_cycle * period, 100);
> +	pwm_init_state(pwm, &state);
>  
> -	pwm_config(pwm, duty, period);
> +	state.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier);
> +	state.duty_cycle = DIV_ROUND_CLOSEST(pwm_ir->duty_cycle * state.period, 100);
>  
>  	edge = ktime_get();
>  
>  	for (i = 0; i < count; i++) {
> -		if (i % 2) // space
> -			pwm_disable(pwm);
> -		else
> -			pwm_enable(pwm);
> +		state.enabled = !(i % 2);
> +		pwm_apply_state(pwm, &state);
>  
>  		edge = ktime_add_us(edge, txbuf[i]);
>  		delta = ktime_us_delta(edge, ktime_get());
> @@ -76,7 +75,8 @@ static int pwm_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
>  			usleep_range(delta, delta + 10);
>  	}
>  
> -	pwm_disable(pwm);
> +	state.enabled = false;
> +	pwm_apply_state(pwm, &state);

I would have added a struct pwm_state to struct pwm_ir and then would
call pwm_init_state() only once in .probe(). But that's subjective if
you like it better or not, so do what you prefer.

The other changes look fine, so:

Acked-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
 
Best regards
Uwe

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

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