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Re: [PATCH v2 3/5] hwmon: (tmp102) Improve handling of initial read delay

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On 06/25/2016 09:40 PM, Guenter Roeck wrote:
[...]
>  /* convert left adjusted 13-bit TMP102 register value to milliCelsius */
> @@ -78,8 +82,16 @@ static struct tmp102 *tmp102_update_device(struct device *dev)
>  	struct tmp102 *tmp102 = dev_get_drvdata(dev);
>  	struct i2c_client *client = tmp102->client;
>  
> +	/* Is it too early to return a conversion ? */
> +	if (time_before(jiffies, tmp102->ready_time)) {
> +		unsigned long sleeptime = tmp102->ready_time - jiffies;
> +
> +		msleep(jiffies_to_msecs(sleeptime));
> +	}
> +

While msleep can indeed work and simplify, in case of usage for
example with thermal framework, if the data is not ready and we return
-EAGAIN, it lets the thermal framework go and read other sensors
instead of being blocked on the tmp102 conversion of data.

Eduardo, Rui: what is your view on this approach?
Patch: https://patchwork.kernel.org/patch/9198961/

-- 
Regards,
Nishanth Menon

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[PATCH v2 3/5] hwmon: (tmp102) Improve handling of initial read delay Guenter Roeck <linux@roeck-us.net> - 2016-06-26 04:50 +0200
  Re: [PATCH v2 3/5] hwmon: (tmp102) Improve handling of initial read  delay Nishanth Menon <nm@ti.com> - 2016-06-26 15:40 +0200
    Re: [PATCH v2 3/5] hwmon: (tmp102) Improve handling of initial read  delay Guenter Roeck <linux@roeck-us.net> - 2016-06-26 16:10 +0200

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