Re: [PATCH] input: Synaptics USB device driver

Dmitry Torokhov
2012-01-04T10:06:03Z

On Wed, Jan 04, 2012 at 10:56:20AM +0100, Oliver Neukum wrote:
> Am Mittwoch, 4. Januar 2012, 10:41:03 schrieb Dmitry Torokhov:
>
>
> > +static void synusb_irq(struct urb *urb)
> > +{
> > + struct synusb *synusb = urb->context;
> > + int error;
> > +
> > + /* Check our status in case we need to bail out early. */
> > + switch (urb->status) {
> > + case 0:
> > + usb_mark_last_busy(synusb->udev);
> > + break;
> > +
> > + case -EOVERFLOW:
> > + dev_err(&synusb->intf->dev,
> > + "%s: OVERFLOW with data length %d, actual length is %d\n",
> > + __func__, SYNUSB_RECV_SIZE, urb->actual_length);
>
> Do you really want to fall through here?

Probably not.

>
> > +
> > + /* Device went away so don't keep trying to read from it. */
> > + case -ECONNRESET:
> > + case -ENOENT:
> > + case -ESHUTDOWN:
> > + return;
> > +
> > + default:
> > + goto resubmit;
> > + break;
> > + }
> > +
> > + if (synusb->flags & SYNUSB_STICK)
> > + synusb_report_stick(synusb);
> > + else
> > + synusb_report_touchpad(synusb);
> > +
> > +resubmit:
> > + error = usb_submit_urb(urb, GFP_ATOMIC);
> > + if (error && error != -EPERM)
> > + dev_err(&synusb->intf->dev,
> > + "%s - usb_submit_urb failed with result: %d",
> > + __func__, error);
> > +}
> > +
>
> [..]
> > +static int synusb_open(struct input_dev *dev)
> > +{
> > + struct synusb *synusb = input_get_drvdata(dev);
> > + int retval = 0;
> > +
> > + dev_err(&synusb->intf->dev, "%s\n", __func__);
> > +
> > + if (usb_autopm_get_interface(synusb->intf) < 0)
> > + return -EIO;
> > +
> > + if (usb_submit_urb(synusb->urb, GFP_KERNEL)) {
> > + dev_err(&synusb->intf->dev,
> > + "%s - usb_submit_urb failed", __func__);
> > + retval = -EIO;
> > + goto out;
> > + }
> > +
> > + synusb->intf->needs_remote_wakeup = 1;
> > +
> > +out:
> > + usb_autopm_put_interface(synusb->intf);
> > + dev_err(&synusb->intf->dev, "%s done: %d\n", __func__, retval);
> > + return retval;
> > +}
> > +
> > +static void synusb_close(struct input_dev *dev)
> > +{
> > + struct synusb *synusb = input_get_drvdata(dev);
> > + int autopm_error;
> > +
> > + autopm_error = usb_autopm_get_interface(synusb->intf);
> > +
> > + usb_kill_urb(synusb->urb);
> > + synusb->intf->needs_remote_wakeup = 0;
> > +
> > + if (!autopm_error)
> > + usb_autopm_put_interface(synusb->intf);
> > +}
> > +
> > +static int synusb_probe(struct usb_interface *intf,
> > + const struct usb_device_id *id)
> > +{
> > + struct usb_device *udev = interface_to_usbdev(intf);
> > + struct usb_endpoint_descriptor *ep;
> > + struct synusb *synusb;
> > + struct input_dev *input_dev;
> > + unsigned int intf_num = intf->cur_altsetting->desc.bInterfaceNumber;
> > + unsigned int altsetting = min(intf->num_altsetting, 1U);
> > + int error;
> > +
> > + error = usb_set_interface(udev, intf_num, altsetting);
> > + if (error) {
> > + dev_err(&udev->dev,
> > + "Can not set alternate setting to %i, error: %i",
> > + altsetting, error);
> > + return error;
> > + }
> > +
> > + ep = synusb_get_in_endpoint(intf->cur_altsetting);
> > + if (!ep)
> > + return -ENODEV;
> > +
> > + synusb = kzalloc(sizeof(*synusb), GFP_KERNEL);
> > + input_dev = input_allocate_device();
> > + if (!synusb || !input_dev) {
> > + error = -ENOMEM;
> > + goto err_free_mem;
> > + }
> > +
> > + synusb->udev = udev;
> > + synusb->intf = intf;
> > + synusb->input = input_dev;
> > +
> > + synusb->flags = id->driver_info;
> > + if (test_bit(SYNUSB_STICK, &synusb->flags) &&
> > + test_bit(SYNUSB_STICK, &synusb->flags)) {
>
> ??? Voodoo ???

Yeah, 2nd should be test_bit(SYNUSB_TOUCHPAD, ...)
>
> > + /*
> > + * This is a combo device, we need to leave only proper
> > + * capability, depending on the interface.
> > + */
> > + clear_bit(intf_num == 1 ? SYNUSB_TOUCHPAD : SYNUSB_STICK,
> > + &synusb->flags);
> > + }
> > +
> > + synusb->urb = usb_alloc_urb(0, GFP_KERNEL);
> > + if (!synusb->urb) {
> > + error = -ENOMEM;
> > + goto err_free_mem;
> > + }
> > +
> > + synusb->data = usb_alloc_coherent(udev, SYNUSB_RECV_SIZE, GFP_KERNEL,
> > + &synusb->urb->transfer_dma);
> > + if (!synusb->data) {
> > + error = -ENOMEM;
> > + goto err_free_urb;
> > + }
> > +
> > + usb_fill_int_urb(synusb->urb, udev,
> > + usb_rcvintpipe(udev, ep->bEndpointAddress),
> > + synusb->data, SYNUSB_RECV_SIZE,
> > + synusb_irq, synusb,
> > + ep->bInterval);
> > + synusb->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
>
> According to the comment in the original driver you must submit the URB.
> Are you sure not doing so is save?

Seems to work here...

>
> > +
> > + if (udev->manufacturer)
> > + strlcpy(synusb->name, udev->manufacturer,
> > + sizeof(synusb->name));
> > +
> > + if (udev->product) {
> > + if (udev->manufacturer)
> > + strlcat(synusb->name, " ", sizeof(synusb->name));
> > + strlcat(synusb->name, udev->product, sizeof(synusb->name));
> > + }
> > +
> > + if (!strlen(synusb->name))
> > + snprintf(synusb->name, sizeof(synusb->name),
> > + "USB Synaptics Device %04x:%04x",
> > + le16_to_cpu(udev->descriptor.idVendor),
> > + le16_to_cpu(udev->descriptor.idProduct));
> > +
> > + if (synusb->flags & SYNUSB_STICK)
> > + strlcat(synusb->name, " (Stick) ", sizeof(synusb->name));
> > +
> > + usb_make_path(udev, synusb->phys, sizeof(synusb->phys));
> > + strlcat(synusb->phys, "/input0", sizeof(synusb->phys));
> > +
> > + input_dev->name = synusb->name; // synusb_get_name(synusb);
> > + input_dev->phys = synusb->phys;
> > + usb_to_input_id(udev, &input_dev->id);
> > + input_dev->dev.parent = &synusb->intf->dev;
> > +
> > + input_dev->open = synusb_open;
> > + input_dev->close = synusb_close;
> > +
> > + input_set_drvdata(input_dev, synusb);
> > +
> > + __set_bit(EV_ABS, input_dev->evbit);
> > + __set_bit(EV_KEY, input_dev->evbit);
> > +
> > + if (synusb->flags & SYNUSB_STICK) {
> > + __set_bit(EV_REL, input_dev->evbit);
> > + __set_bit(REL_X, input_dev->relbit);
> > + __set_bit(REL_Y, input_dev->relbit);
> > + input_set_abs_params(input_dev, ABS_PRESSURE, 0, 127, 0, 0);
> > + } else {
> > + input_set_abs_params(input_dev, ABS_X, xmin, xmax, 0, 0);
> > + input_set_abs_params(input_dev, ABS_Y, ymin, ymax, 0, 0);
> > + input_set_abs_params(input_dev, ABS_PRESSURE, 0, 255, 0, 0);
> > + input_set_abs_params(input_dev, ABS_TOOL_WIDTH, 0, 15, 0, 0);
> > + __set_bit(BTN_TOUCH, input_dev->keybit);
> > + __set_bit(BTN_TOOL_FINGER, input_dev->keybit);
> > + __set_bit(BTN_TOOL_DOUBLETAP, input_dev->keybit);
> > + __set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
> > + }
> > +
> > + __set_bit(BTN_LEFT, input_dev->keybit);
> > + __set_bit(BTN_RIGHT, input_dev->keybit);
> > + __set_bit(BTN_MIDDLE, input_dev->keybit);
> > + if (synusb->flags & SYNUSB_AUXDISPLAY)
> > + __set_bit(BTN_MISC, input_dev->keybit);
> > +
> > + error = input_register_device(input_dev);
> > + if (error) {
> > + dev_err(&udev->dev, "Failed to register input device, error %d\n",
> > + error);
> > + goto err_free_dma;
> > + }
> > +
> > + usb_set_intfdata(intf, synusb);
> > + return 0;
> > +
> > +err_free_dma:
> > + usb_free_coherent(udev, SYNUSB_RECV_SIZE, synusb->data,
> > + synusb->urb->transfer_dma);
> > +err_free_urb:
> > + usb_free_urb(synusb->urb);
> > +err_free_mem:
> > + input_free_device(input_dev);
> > + kfree(synusb);
> > +
> > + return error;
> > +}
> > +
>
> [..]
> > +static struct usb_driver synusb_driver = {
> > + .name = "synaptics_usb",
> > + .probe = synusb_probe,
> > + .disconnect = synusb_disconnect,
> > + .id_table = synusb_idtable,
> > + .suspend = synusb_suspend,
> > + .resume = synusb_resume,
> > + .reset_resume = synusb_reset_resume,
>
> You've killed the support for reset. That is not cool.

OK.

Thanks.

--
Dmitry