Re: [RFC] [PATCH V2 1/2] input: CMA3000 Accelerometer driver

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Fri, Aug 13, 2010 at 08:34:07AM -0500, Murphy, Dan wrote:
> Hemanth
> I have a few comments on this patch.
> 
> +static ssize_t cma3000_store_attr_mdfftmr(struct device *dev,
> +					struct device_attribute *attr,
> +					const char *buf, size_t count)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct cma3000_accl_data *data = platform_get_drvdata(pdev);
> +	unsigned long val;
> +	int error;
> +
> +	error = strict_strtoul(buf, 0, &val);
> +	if (error)
> +		return error;
> +
> +	mutex_lock(&data->mutex);
> +	data->pdata.mdfftmr = val;
> +
> +	disable_irq(data->client->irq);
> You should use disable_irq_nosync here.  This may not work properly on SMP.

This is an incorrect statement. disable_irq() is not safe to use on SMP when
caller may not sleep (since it will wait for the running handler to
complete), but in this context it is perfectly safe,

-- 
Dmitry