On Wed, Jul 24, 2013 at 06:41:56PM +0300, Tomas Winkler wrote: > Export fw status register through sysfs interface. > The interface is for applications that monitors > fw health. > > Signed-off-by: Natalia Ovsyanikov <[email protected]> > Signed-off-by: Tomas Winkler <[email protected]> > --- > drivers/misc/mei/main.c | 54 > ++++++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 51 insertions(+), 3 deletions(-) > > diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c > index 173ff09..64e36a8 100644 > --- a/drivers/misc/mei/main.c > +++ b/drivers/misc/mei/main.c > @@ -659,6 +659,44 @@ out: > return mask; > } > > +/** > + * mei_show_fw_status - mei device attribute show method > + * > + * @dev: device pointer > + * @attr: attribute pointer > + * @buf: char out buffer > + * > + * returns number of the bytes, printed into the buffer > + */ > + > +static ssize_t mei_show_fw_status(struct device *device, > + struct device_attribute *attr, char *buf) > +{ > + struct mei_device *dev = dev_get_drvdata(device); > + u32 fw_status; > + int err; > + > + mutex_lock(&dev->device_lock); > + err = mei_fw_status(dev, &fw_status); > + mutex_unlock(&dev->device_lock); > + if (err) { > + dev_err(device, "attribute show: read fw_status error = %d\n", > + err); > + return err; > + } > + > + dev_dbg(device, "attribute show: fw_status 0x%x\n", fw_status); > + return sprintf(buf, "%08X\n", fw_status); > +} > +static DEVICE_ATTR(fw_status, S_IRUGO, mei_show_fw_status, NULL); > +static struct attribute *mei_attributes[] = { > + &dev_attr_fw_status.attr, > + NULL > +}; > +static const struct attribute_group mei_attr_group = { > + .attrs = mei_attributes, > +}; > + > /* > * file operations structure will be used for mei char device. > */ > @@ -685,17 +723,22 @@ static struct miscdevice mei_misc_device = { > .minor = MISC_DYNAMIC_MINOR, > }; > > - > int mei_register(struct mei_device *dev) > { > + struct device *device = &dev->pdev->dev; > int ret; > - mei_misc_device.parent = &dev->pdev->dev; > + > + mei_misc_device.parent = device; > ret = misc_register(&mei_misc_device); > if (ret) > return ret; > > + ret = sysfs_create_group(&device->kobj, &mei_attr_group); > + if (ret) > + return ret;
And you just lost the race with userspace (you told it you had a device, it went and scanned your attributes and saved them, then you registered more...) Please use the dev_groups field for your class to properly have the driver core register these before userspace is told about the device, that's the correct way to do this. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
