Re: [PATCH 09/12] hdaps: Add new sysfs attributes

From: Pavel Machek
Date: Tue Aug 08 2006 - 08:49:26 EST


> This patch adds 4 new r/w sysfs attributes to the hdaps driver:
> /sys/devices/platform/hdaps/sampling_rate:
> This determines the frequency of hardware queries and input device updates.
> Default=50.
> /sys/devices/platform/hdaps/oversampling_ratio:
> When set to X, the embedded controller is told to do physical accelerometer
> measurements at a rate that is X times higher than the rate at which
> the driver reads those measurements (i.e., X*sampling_rate). This
> reduces sample phase difference is, and useful for the running average
> filter (see next). Default=5
> /sys/devices/platform/hdaps/running_avg_filter_order:
> When set to X, reported readouts will be the average of the last X physical
> accelerometer measurements. Current firmware allows 1<=X<=8. Setting to a
> high value decreases readout fluctuations. The averaging is handled
> by the embedded controller, so no CPU resources are used. Default=2.
> /sys/devices/platform/hdaps/fake_data_mode:
> If set to 1, enables a test mode where the physical accelerometer readouts
> are replaced with an incrementing counter. This is useful for checking the
> regularity of the sampling interval and driver<->userspace communication,
> which is useful for development and testing of the hdapd userspace daemon.
> Signed-off-by: Shem Multinymous <multinymous@xxxxxxxxx>

Signed-off-by: Pavel Machek <pavel@xxxxxxx>

> +static ssize_t hdaps_fake_data_mode_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + int on, ret;
> + if (sscanf(buf, "%d", &on) != 1 || on<0 || on>1) {
> + printk(KERN_WARNING
> + "fake_data should be 0 or 1\n");

Kill the printk?
Thanks for all the (sleeping) penguins.
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