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In-Reply-To: <20191203101509.wte47aad5k4mqu2y@pengutronix.de>
From:   Fabio Estevam <festevam@gmail.com>
Date:   Tue, 3 Dec 2019 09:04:58 -0300
Message-ID: <CAOMZO5Cn993y9VeFN6hPO3-cfNnUKiuFd_rqAZ8htz=dO6t6ig@mail.gmail.com>
Subject: Re: Issue with imx_get_temp()
To:     Marco Felsch <m.felsch@pengutronix.de>
Cc:     Igor Plyatov <plyatov@gmail.com>, Zhang Rui <rui.zhang@intel.com>,
        Eduardo Valentin <edubezval@gmail.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Amit Kucheria <amit.kucheria@verdurent.com>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        NXP Linux Team <linux-imx@nxp.com>, linux-pm@vger.kernel.org,
        "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
        <linux-arm-kernel@lists.infradead.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
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Sender: linux-kernel-owner@vger.kernel.org
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Hi Marco,

On Tue, Dec 3, 2019 at 7:15 AM Marco Felsch <m.felsch@pengutronix.de> wrote:

> Mh.. it seems that the irq gets enabled before a irq-handler is
> registered. As your backlog shows the thermal_zone_device_register()
> triggers a imx_get_temp() and during boot the irq_enabled is false and
> it seems that your temperature is below the alarm_temp. So in such a
> case the enable_irq() is executed. I don't know what happens if we
> enable a irq without a irq-handler.

I think your analysis makes sense.

Should we move the ' data->irq_enabled = true' just prior to calling
thermal_zone_device_register()?

--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -803,6 +803,7 @@ static int imx_thermal_probe(struct platform_device *pdev)
                goto legacy_cleanup;
        }

+       data->irq_enabled = true;
        data->tz = thermal_zone_device_register("imx_thermal_zone",
                                                IMX_TRIP_NUM,
                                                BIT(IMX_TRIP_PASSIVE), data,
@@ -837,7 +838,6 @@ static int imx_thermal_probe(struct platform_device *pdev)
        regmap_write(map, data->socdata->sensor_ctrl + REG_SET,
                     data->socdata->measure_temp_mask);

-       data->irq_enabled = true;
        data->mode = THERMAL_DEVICE_ENABLED;

        ret = devm_request_threaded_irq(&pdev->dev, data->irq,