[PATCH 4/5] register control handlers using V4L2 control framework

[Florian Echtler]

This patch registers four standard control handlers using the corresponding
V4L2 framework.

Signed-off-by: Florian Echtler <f...@butterbrot.org>
---
 drivers/input/touchscreen/sur40.c | 51 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/drivers/input/touchscreen/sur40.c 
b/drivers/input/touchscreen/sur40.c
index 7f6461d..66ef7e6 100644
--- a/drivers/input/touchscreen/sur40.c
+++ b/drivers/input/touchscreen/sur40.c
@@ -38,6 +38,7 @@
 #include <media/v4l2-device.h>
 #include <media/v4l2-dev.h>
 #include <media/v4l2-ioctl.h>
+#include <media/v4l2-ctrls.h>
 #include <media/videobuf2-v4l2.h>
 #include <media/videobuf2-dma-sg.h>
 
@@ -198,6 +199,7 @@ struct sur40_state {
        struct video_device vdev;
        struct mutex lock;
        struct v4l2_pix_format pix_fmt;
+       struct v4l2_ctrl_handler ctrls;
 
        struct vb2_queue queue;
        struct list_head buf_list;
@@ -207,6 +209,7 @@ struct sur40_state {
        struct sur40_data *bulk_in_buffer;
        size_t bulk_in_size;
        u8 bulk_in_epaddr;
+       u8 vsvideo;
 
        char phys[64];
 };
@@ -220,6 +223,11 @@ struct sur40_buffer {
 static const struct video_device sur40_video_device;
 static const struct vb2_queue sur40_queue;
 static void sur40_process_video(struct sur40_state *sur40);
+static int sur40_s_ctrl(struct v4l2_ctrl *ctrl);
+
+static const struct v4l2_ctrl_ops sur40_ctrl_ops = {
+       .s_ctrl = sur40_s_ctrl,
+};
 
 /*
  * Note: an earlier, non-public version of this driver used USB_RECIP_ENDPOINT
@@ -722,6 +730,23 @@ static int sur40_probe(struct usb_interface *interface,
        sur40->vdev.queue = &sur40->queue;
        video_set_drvdata(&sur40->vdev, sur40);
 
+       /* initialize the control handler for 4 controls */
+       v4l2_ctrl_handler_init(&sur40->ctrls, 4);
+       sur40->v4l2.ctrl_handler = &sur40->ctrls;
+
+       v4l2_ctrl_new_std(&sur40->ctrls, &sur40_ctrl_ops, V4L2_CID_BRIGHTNESS,
+         SUR40_BRIGHTNESS_MIN, SUR40_BRIGHTNESS_MAX, 1, SUR40_BRIGHTNESS_DEF);
+
+       v4l2_ctrl_new_std(&sur40->ctrls, &sur40_ctrl_ops, V4L2_CID_CONTRAST,
+         SUR40_CONTRAST_MIN, SUR40_CONTRAST_MAX, 1, SUR40_CONTRAST_DEF);
+
+       v4l2_ctrl_new_std(&sur40->ctrls, &sur40_ctrl_ops, V4L2_CID_GAIN,
+         SUR40_GAIN_MIN, SUR40_GAIN_MAX, 1, SUR40_GAIN_DEF);
+
+       v4l2_ctrl_new_std(&sur40->ctrls, &sur40_ctrl_ops,
+         V4L2_CID_BACKLIGHT_COMPENSATION, SUR40_BACKLIGHT_MIN,
+         SUR40_BACKLIGHT_MAX, 1, SUR40_BACKLIGHT_DEF);
+
        error = video_register_device(&sur40->vdev, VFL_TYPE_TOUCH, -1);
        if (error) {
                dev_err(&interface->dev,
@@ -754,6 +779,7 @@ static void sur40_disconnect(struct usb_interface 
*interface)
 {
        struct sur40_state *sur40 = usb_get_intfdata(interface);
 
+       v4l2_ctrl_handler_free(&sur40->ctrls);
        video_unregister_device(&sur40->vdev);
        v4l2_device_unregister(&sur40->v4l2);
 
@@ -947,6 +973,31 @@ static int sur40_vidioc_g_fmt(struct file *file, void 
*priv,
        return 0;
 }
 
+static int sur40_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+       struct sur40_state *sur40  = container_of(ctrl->handler,
+         struct sur40_state, ctrls);
+       u8 value = sur40->vsvideo;
+
+       switch (ctrl->id) {
+       case V4L2_CID_BRIGHTNESS:
+               sur40_set_irlevel(sur40, ctrl->val);
+               break;
+       case V4L2_CID_CONTRAST:
+               value = (value & 0x0F) | (ctrl->val << 4);
+               sur40_set_vsvideo(sur40, value);
+               break;
+       case V4L2_CID_GAIN:
+               value = (value & 0xF0) | (ctrl->val);
+               sur40_set_vsvideo(sur40, value);
+               break;
+       case V4L2_CID_BACKLIGHT_COMPENSATION:
+               sur40_set_preprocessor(sur40, ctrl->val);
+               break;
+       }
+       return 0;
+}
+
 static int sur40_ioctl_parm(struct file *file, void *priv,
                            struct v4l2_streamparm *p)
 {
-- 
2.7.4