diff options
Diffstat (limited to 'drivers/media/rc/rc-main.c')
| -rw-r--r-- | drivers/media/rc/rc-main.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c index f1b67db45e78..fa8b9575a84c 100644 --- a/drivers/media/rc/rc-main.c +++ b/drivers/media/rc/rc-main.c @@ -969,6 +969,130 @@ out: return ret; } +/** + * struct rc_filter_attribute - Device attribute relating to a filter type. + * @attr: Device attribute. + * @type: Filter type. + * @mask: false for filter value, true for filter mask. + */ +struct rc_filter_attribute { + struct device_attribute attr; + enum rc_filter_type type; + bool mask; +}; +#define to_rc_filter_attr(a) container_of(a, struct rc_filter_attribute, attr) + +#define RC_FILTER_ATTR(_name, _mode, _show, _store, _type, _mask) \ + struct rc_filter_attribute dev_attr_##_name = { \ + .attr = __ATTR(_name, _mode, _show, _store), \ + .type = (_type), \ + .mask = (_mask), \ + } + +/** + * show_filter() - shows the current scancode filter value or mask + * @device: the device descriptor + * @attr: the device attribute struct + * @buf: a pointer to the output buffer + * + * This routine is a callback routine to read a scancode filter value or mask. + * It is trigged by reading /sys/class/rc/rc?/[wakeup_]filter[_mask]. + * It prints the current scancode filter value or mask of the appropriate filter + * type in hexadecimal into @buf and returns the size of the buffer. + * + * Bits of the filter value corresponding to set bits in the filter mask are + * compared against input scancodes and non-matching scancodes are discarded. + * + * dev->lock is taken to guard against races between device registration, + * store_filter and show_filter. + */ +static ssize_t show_filter(struct device *device, + struct device_attribute *attr, + char *buf) +{ + struct rc_dev *dev = to_rc_dev(device); + struct rc_filter_attribute *fattr = to_rc_filter_attr(attr); + u32 val; + + /* Device is being removed */ + if (!dev) + return -EINVAL; + + mutex_lock(&dev->lock); + if (!dev->s_filter) + val = 0; + else if (fattr->mask) + val = dev->scancode_filters[fattr->type].mask; + else + val = dev->scancode_filters[fattr->type].data; + mutex_unlock(&dev->lock); + + return sprintf(buf, "%#x\n", val); +} + +/** + * store_filter() - changes the scancode filter value + * @device: the device descriptor + * @attr: the device attribute struct + * @buf: a pointer to the input buffer + * @len: length of the input buffer + * + * This routine is for changing a scancode filter value or mask. + * It is trigged by writing to /sys/class/rc/rc?/[wakeup_]filter[_mask]. + * Returns -EINVAL if an invalid filter value for the current protocol was + * specified or if scancode filtering is not supported by the driver, otherwise + * returns @len. + * + * Bits of the filter value corresponding to set bits in the filter mask are + * compared against input scancodes and non-matching scancodes are discarded. + * + * dev->lock is taken to guard against races between device registration, + * store_filter and show_filter. + */ +static ssize_t store_filter(struct device *device, + struct device_attribute *attr, + const char *buf, + size_t count) +{ + struct rc_dev *dev = to_rc_dev(device); + struct rc_filter_attribute *fattr = to_rc_filter_attr(attr); + struct rc_scancode_filter local_filter, *filter; + int ret; + unsigned long val; + + /* Device is being removed */ + if (!dev) + return -EINVAL; + + ret = kstrtoul(buf, 0, &val); + if (ret < 0) + return ret; + + /* Scancode filter not supported (but still accept 0) */ + if (!dev->s_filter) + return val ? -EINVAL : count; + + mutex_lock(&dev->lock); + + /* Tell the driver about the new filter */ + filter = &dev->scancode_filters[fattr->type]; + local_filter = *filter; + if (fattr->mask) + local_filter.mask = val; + else + local_filter.data = val; + ret = dev->s_filter(dev, fattr->type, &local_filter); + if (ret < 0) + goto unlock; + + /* Success, commit the new filter */ + *filter = local_filter; + +unlock: + mutex_unlock(&dev->lock); + return count; +} + static void rc_dev_release(struct device *device) { } @@ -1000,9 +1124,21 @@ static int rc_dev_uevent(struct device *device, struct kobj_uevent_env *env) */ static DEVICE_ATTR(protocols, S_IRUGO | S_IWUSR, show_protocols, store_protocols); +static RC_FILTER_ATTR(filter, S_IRUGO|S_IWUSR, + show_filter, store_filter, RC_FILTER_NORMAL, false); +static RC_FILTER_ATTR(filter_mask, S_IRUGO|S_IWUSR, + show_filter, store_filter, RC_FILTER_NORMAL, true); +static RC_FILTER_ATTR(wakeup_filter, S_IRUGO|S_IWUSR, + show_filter, store_filter, RC_FILTER_WAKEUP, false); +static RC_FILTER_ATTR(wakeup_filter_mask, S_IRUGO|S_IWUSR, + show_filter, store_filter, RC_FILTER_WAKEUP, true); static struct attribute *rc_dev_attrs[] = { &dev_attr_protocols.attr, + &dev_attr_filter.attr.attr, + &dev_attr_filter_mask.attr.attr, + &dev_attr_wakeup_filter.attr.attr, + &dev_attr_wakeup_filter_mask.attr.attr, NULL, }; |