diff options
Diffstat (limited to 'drivers/usb/gadget/storage_common.c')
-rw-r--r-- | drivers/usb/gadget/storage_common.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/drivers/usb/gadget/storage_common.c b/drivers/usb/gadget/storage_common.c index 70a474c..0c7f16b 100644 --- a/drivers/usb/gadget/storage_common.c +++ b/drivers/usb/gadget/storage_common.c @@ -913,3 +913,40 @@ static ssize_t fsg_store_file(struct device *dev, struct device_attribute *attr, up_write(filesem); return (rc < 0 ? rc : count); } + +static ssize_t fsg_show_cdrom (struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + + return sprintf(buf, "%d\n", curlun->cdrom); +} + +static ssize_t fsg_store_cdrom(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + ssize_t rc; + struct fsg_lun *curlun = fsg_lun_from_dev(dev); + struct rw_semaphore *filesem = dev_get_drvdata(dev); + unsigned cdrom; + + rc = kstrtouint(buf, 2, &cdrom); + if (rc) + return rc; + + /* + * Allow the cdrom status to change only while the + * backing file is closed. + */ + down_read(filesem); + if (fsg_lun_is_open(curlun)) { + LDBG(curlun, "cdrom status change prevented\n"); + rc = -EBUSY; + } else { + curlun->cdrom = cdrom; + LDBG(curlun, "cdrom status set to %d\n", curlun->cdrom); + rc = count; + } + up_read(filesem); + return rc; +} |