On Fri, May 31, 2019 at 02:56:42PM +0800, Chester Lin wrote: > An acpi_eject_show attribute for users to monitor current status because > sometimes it might take time to finish an ejection so we need to know > whether it is still in progress or not. > > Signed-off-by: Chester Lin <clin@xxxxxxxx> > --- > drivers/acpi/device_sysfs.c | 20 +++++++++++++++++++- > drivers/acpi/internal.h | 1 + > drivers/acpi/scan.c | 27 +++++++++++++++++++++++++++ > 3 files changed, 47 insertions(+), 1 deletion(-) > > diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c > index 78c2653bf020..70b22eec6bbc 100644 > --- a/drivers/acpi/device_sysfs.c > +++ b/drivers/acpi/device_sysfs.c > @@ -403,7 +403,25 @@ acpi_eject_store(struct device *d, struct device_attribute *attr, > return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; > } > > -static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store); > +static ssize_t acpi_eject_show(struct device *d, > + struct device_attribute *attr, char *buf) > +{ > + struct acpi_device *acpi_device = to_acpi_device(d); > + acpi_object_type not_used; > + acpi_status status; > + > + if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) > + && !acpi_device->driver) > + return -ENODEV; > + > + status = acpi_get_type(acpi_device->handle, ¬_used); > + if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) > + return -ENODEV; > + > + return sprintf(buf, "%s\n", acpi_eject_status_string(acpi_device)); > +} > + > +static DEVICE_ATTR(eject, 0644, acpi_eject_show, acpi_eject_store); DEVICE_ATTR_RW()? And you need to document the new sysfs file in Documentation/ABI/ thanks, greg k-h