static void appledisplay_work(struct work_struct *work)
{
struct appledisplay *pdata =
container_of(work, struct appledisplay, work.work);
int retval;
retval = appledisplay_bl_get_brightness(pdata->bd);
if (retval >= 0)
pdata->bd->props.brightness = retval;
/* Poll again in about 125ms if there's still a button pressed */
if (pdata->button_pressed)
schedule_delayed_work(&pdata->work, HZ / 8);
}
static int appledisplay_probe(struct usb_interface *iface,
const struct usb_device_id *id)
{
struct backlight_properties props;
struct appledisplay *pdata;
struct usb_device *udev = interface_to_usbdev(iface);
struct usb_host_interface *iface_desc;
struct usb_endpoint_descriptor *endpoint;
int int_in_endpointAddr = 0;
int i, retval = -ENOMEM, brightness;
char bl_name[20];
/* set up the endpoint information */
/* use only the first interrupt-in endpoint */
iface_desc = iface->cur_altsetting;
for (i = 0; i < iface_desc->desc.bNumEndpoints; i++) {
endpoint = &iface_desc->endpoint[i].desc;
if (!int_in_endpointAddr && usb_endpoint_is_int_in(endpoint)) {
/* we found an interrupt in endpoint */
int_in_endpointAddr = endpoint->bEndpointAddress;
break;
}
}
if (!int_in_endpointAddr) {
dev_err(&iface->dev, "Could not find int-in endpoint\n");
return -EIO;
}
/* allocate memory for our device state and initialize it */
pdata = kzalloc(sizeof(struct appledisplay), GFP_KERNEL);
if (!pdata) {
retval = -ENOMEM;
dev_err(&iface->dev, "Out of memory\n");
goto error;
}
pdata->udev = udev;
spin_lock_init(&pdata->lock);
INIT_DELAYED_WORK(&pdata->work, appledisplay_work);
/* Allocate buffer for control messages */
pdata->msgdata = kmalloc(ACD_MSG_BUFFER_LEN, GFP_KERNEL);
if (!pdata->msgdata) {
retval = -ENOMEM;
dev_err(&iface->dev,
"Allocating buffer for control messages failed\n");
goto error;
}
/* Allocate interrupt URB */
pdata->urb = usb_alloc_urb(0, GFP_KERNEL);
if (!pdata->urb) {
retval = -ENOMEM;
dev_err(&iface->dev, "Allocating URB failed\n");
goto error;
}
/* Allocate buffer for interrupt data */
pdata->urbdata = usb_buffer_alloc(pdata->udev, ACD_URB_BUFFER_LEN,
GFP_KERNEL, &pdata->urb->transfer_dma);
if (!pdata->urbdata) {
retval = -ENOMEM;
dev_err(&iface->dev, "Allocating URB buffer failed\n");
goto error;
}
/* Configure interrupt URB */
usb_fill_int_urb(pdata->urb, udev,
usb_rcvintpipe(udev, int_in_endpointAddr),
pdata->urbdata, ACD_URB_BUFFER_LEN, appledisplay_complete,
pdata, 1);
if (usb_submit_urb(pdata->urb, GFP_KERNEL)) {
retval = -EIO;
dev_err(&iface->dev, "Submitting URB failed\n");
goto error;
}
/* Register backlight device */
snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
atomic_inc_return(&count_displays) - 1);
memset(&props, 0, sizeof(struct backlight_properties));
props.max_brightness = 0xff;
pdata->bd = backlight_device_register(bl_name, NULL, pdata,
&appledisplay_bl_data, &props);
if (IS_ERR(pdata->bd)) {
dev_err(&iface->dev, "Backlight registration failed\n");
retval = PTR_ERR(pdata->bd);
goto error;
}
/* Try to get brightness */
brightness = appledisplay_bl_get_brightness(pdata->bd);
if (brightness < 0) {
retval = brightness;
dev_err(&iface->dev,
"Error while getting initial brightness: %d\n", retval);
goto error;
}
/* Set brightness in backlight device */
pdata->bd->props.brightness = brightness;
/* save our data pointer in the interface device */
usb_set_intfdata(iface, pdata);
printk(KERN_INFO "appledisplay: Apple Cinema Display connected\n");
return 0;
error:
if (pdata) {
if (pdata->urb) {
usb_kill_urb(pdata->urb);
if (pdata->urbdata)
usb_buffer_free(pdata->udev, ACD_URB_BUFFER_LEN,
pdata->urbdata, pdata->urb->transfer_dma);
usb_free_urb(pdata->urb);
}
if (pdata->bd && !IS_ERR(pdata->bd))
backlight_device_unregister(pdata->bd);
kfree(pdata->msgdata);
}
usb_set_intfdata(iface, NULL);
kfree(pdata);
return retval;
}
}
static struct backlight_properties appledisplay_bl_data = {
.owner = THIS_MODULE,
.get_brightness = appledisplay_bl_get_brightness,
.update_status = appledisplay_bl_update_status,
.max_brightness = 0xFF
};
static void appledisplay_work(void *private)
{
struct appledisplay *pdata = private;
int retval;
up(&pdata->bd->sem);
retval = appledisplay_bl_get_brightness(pdata->bd);
if (retval >= 0)
pdata->bd->props->brightness = retval;
down(&pdata->bd->sem);
/* Poll again in about 125ms if there's still a button pressed */
if (pdata->button_pressed)
schedule_delayed_work(&pdata->work, HZ / 8);
}
static int appledisplay_probe(struct usb_interface *iface,
const struct usb_device_id *id)
{
struct appledisplay *pdata;
struct usb_device *udev = interface_to_usbdev(iface);
struct usb_host_interface *iface_desc;
