linux-kernel - Re: [PATCH 5/5] thermal: rockchip: handle the set

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Message-ID: <20161122205142.GA45366@google.com>
Date:   Tue, 22 Nov 2016 12:51:43 -0800
From:   Brian Norris <briannorris@...omium.org>
To:     Caesar Wang <wxt@...k-chips.com>
Cc:     edubezval@...il.com, rui.zhang@...el.com,
        linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-rockchip@...ts.infradead.org, heiko@...ech.de,
        smbarber@...omium.org
Subject: Re: [PATCH 5/5] thermal: rockchip: handle the set_trips without the
 trip points.

On Tue, Nov 22, 2016 at 08:34:48PM +0800, Caesar Wang wrote:
> In some cases, some sensors didn't need the trip points, the
> set_trips will return {-INT_MAX, INT_MAX} to trigger thermal alarm.
> 
> Signed-off-by: Caesar Wang <wxt@...k-chips.com>
> ---
> 
>  drivers/thermal/rockchip_thermal.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/thermal/rockchip_thermal.c b/drivers/thermal/rockchip_thermal.c
> index f4d4be9..5b9c346 100644
> --- a/drivers/thermal/rockchip_thermal.c
> +++ b/drivers/thermal/rockchip_thermal.c
> @@ -200,6 +200,7 @@ struct rockchip_thermal_data {
>  #define TSADCV3_AUTO_Q_SEL_EN			BIT(1)
>  
>  #define TSADCV2_INT_SRC_EN(chn)			BIT(chn)
> +#define TSADCV2_INT_SRC_SHIFT(chn)		chn
>  #define TSADCV2_SHUT_2GPIO_SRC_EN(chn)		BIT(4 + (chn))
>  #define TSADCV2_SHUT_2CRU_SRC_EN(chn)		BIT(8 + (chn))
>  
> @@ -903,10 +904,22 @@ static int rockchip_thermal_set_trips(void *_sensor, int low, int high)
>  	struct rockchip_thermal_sensor *sensor = _sensor;
>  	struct rockchip_thermal_data *thermal = sensor->thermal;
>  	const struct rockchip_tsadc_chip *tsadc = thermal->chip;
> +	u32 int_clr;
>  
>  	dev_dbg(&thermal->pdev->dev, "%s: sensor %d: low: %d, high %d\n",
>  		__func__, sensor->id, low, high);
>  
> +	/*
> +	 * In some cases, some sensors didn't need the trip points, the
> +	 * set_trips will return {-INT_MAX, INT_MAX} to trigger thermal alarm.

This language is a little unclear. AFAICT, set_trips is not "returning"
those values, it's "passing" them as arguments.

> +	 */
> +	if (high == INT_MAX) {
> +		int_clr = readl_relaxed(thermal->regs + TSADCV2_INT_EN);
> +		int_clr |= 0 << TSADCV2_INT_SRC_SHIFT(sensor->id);

Uhh, really? This line is a no-op; you're just OR'ing a value of zero...

It also seems like this should use the existing shift macro,
TSADCV2_INT_SRC_EN(). So:

		int_clr &= ~TSADCV2_INT_SRC_EN(sensor->id);

> +		writel_relaxed(int_clr, thermal->regs + TSADCV2_INT_EN);
> +		return 0;
> +	}
> +
>  	tsadc->set_alarm_temp(&tsadc->table,
>  			      sensor->id, thermal->regs, high);

Given that you have a level of indirection here for ->set_alarm_temp(),
it seems like you should not be doing the above register programming
directly in this function; it should either go in the ->set_alarm_temp()
callback, or in a new callback like ->disable_alarm().

Brian

>  
> -- 
> 2.7.4
>