V4L/DVB (8123): Add support for em2860 based PointNix Intra-Oral Camera

em28xx-cards.c
em28xx-input.c
em28xx-video.c
em28xx.h
 - Add support for the PointNix Intra-Oral Camera, which required addition of
   a construct for reading the "snapshot" button (provided on the em2860 and
   em2880 chips, but this is the first case where I have seen it actually used
   in a product). The button is wired to pin 56 on the em2880.

   http://www.pointnix.com/ENG/dental/product_02.asp

   Thanks to Roberto Mantovani <rmantovani@libero.it> for testing the changes

Signed-off-by: Devin Heitmueller <devin.heitmueller@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 87 insertions, 0 deletions

diff --git a/drivers/media/video/em28xx/em28xx-input.c b/drivers/media/video/em28xx/em28xx-input.c
index bb58071..eab3d95 100644
--- a/drivers/media/video/em28xx/em28xx-input.c
+++ b/drivers/media/video/em28xx/em28xx-input.c
@@ -30,6 +30,10 @@
 
 #include "em28xx.h"
 
+#define EM28XX_SNAPSHOT_KEY KEY_CAMERA
+#define EM28XX_SBUTTON_QUERY_INTERVAL 500
+#define EM28XX_R0C_USBSUSP_SNAPSHOT 0x20
+
 static unsigned int ir_debug;
 module_param(ir_debug, int, 0644);
 MODULE_PARM_DESC(ir_debug, "enable debug messages [IR]");
@@ -124,6 +128,89 @@ int em28xx_get_key_pinnacle_usb_grey(struct IR_i2c *ir, u32 *ir_key,
 	return 1;
 }
 
+static void em28xx_query_sbutton(struct work_struct *work)
+{
+	/* Poll the register and see if the button is depressed */
+	struct em28xx *dev =
+		container_of(work, struct em28xx, sbutton_query_work.work);
+	int ret;
+
+	ret = em28xx_read_reg(dev, EM28XX_R0C_USBSUSP);
+
+	if (ret & EM28XX_R0C_USBSUSP_SNAPSHOT) {
+		u8 cleared;
+		/* Button is depressed, clear the register */
+		cleared = ((u8) ret) & ~EM28XX_R0C_USBSUSP_SNAPSHOT;
+		em28xx_write_regs(dev, EM28XX_R0C_USBSUSP, &cleared, 1);
+
+		/* Not emulate the keypress */
+		input_report_key(dev->sbutton_input_dev, EM28XX_SNAPSHOT_KEY,
+				 1);
+		/* Now unpress the key */
+		input_report_key(dev->sbutton_input_dev, EM28XX_SNAPSHOT_KEY,
+				 0);
+	}
+
+	/* Schedule next poll */
+	schedule_delayed_work(&dev->sbutton_query_work,
+			      msecs_to_jiffies(EM28XX_SBUTTON_QUERY_INTERVAL));
+}
+
+void em28xx_register_snapshot_button(struct em28xx *dev)
+{
+	struct input_dev *input_dev;
+	int err;
+
+	em28xx_info("Registering snapshot button...\n");
+	input_dev = input_allocate_device();
+	if (!input_dev) {
+		em28xx_errdev("input_allocate_device failed\n");
+		return;
+	}
+
+	usb_make_path(dev->udev, dev->snapshot_button_path,
+		      sizeof(dev->snapshot_button_path));
+	strlcat(dev->snapshot_button_path, "/sbutton",
+		sizeof(dev->snapshot_button_path));
+	INIT_DELAYED_WORK(&dev->sbutton_query_work, em28xx_query_sbutton);
+
+	input_dev->name = "em28xx snapshot button";
+	input_dev->phys = dev->snapshot_button_path;
+	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+	set_bit(EM28XX_SNAPSHOT_KEY, input_dev->keybit);
+	input_dev->keycodesize = 0;
+	input_dev->keycodemax = 0;
+	input_dev->id.bustype = BUS_USB;
+	input_dev->id.vendor = le16_to_cpu(dev->udev->descriptor.idVendor);
+	input_dev->id.product = le16_to_cpu(dev->udev->descriptor.idProduct);
+	input_dev->id.version = 1;
+	input_dev->dev.parent = &dev->udev->dev;
+
+	err = input_register_device(input_dev);
+	if (err) {
+		em28xx_errdev("input_register_device failed\n");
+		input_free_device(input_dev);
+		return;
+	}
+
+	dev->sbutton_input_dev = input_dev;
+	schedule_delayed_work(&dev->sbutton_query_work,
+			      msecs_to_jiffies(EM28XX_SBUTTON_QUERY_INTERVAL));
+	return;
+
+}
+
+void em28xx_deregister_snapshot_button(struct em28xx *dev)
+{
+	if (dev->sbutton_input_dev != NULL) {
+		em28xx_info("Deregistering snapshot button\n");
+		cancel_rearming_delayed_work(&dev->sbutton_query_work);
+		input_unregister_device(dev->sbutton_input_dev);
+		dev->sbutton_input_dev = NULL;
+	}
+	return;
+}
+
 /* ----------------------------------------------------------------------
  * Local variables:
  * c-basic-offset: 8