V4L/DVB (11213): gspca - sq905c: New subdriver.

The code in the new sq905c.c is based upon the structure of the code in
gspca/sq905.c, and upon the code in libgphoto2/camlibs/digigr8, which supports
the same set of cameras in stillcam mode. I am a co-author of gspca/sq905.c and
I am the sole author of libgphoto2/camlibs/digigr8, which is licensed under the
LGPL. I hereby give myself permission to use my own code from libgphoto2 in
gspca/sq905c.c.

Signed-off-by: Theodore Kilgore <kilgota@auburn.edu>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/gspca/Kconfig b/drivers/media/video/gspca/Kconfig
index a0f05ef..578dc4f 100644
--- a/drivers/media/video/gspca/Kconfig
+++ b/drivers/media/video/gspca/Kconfig
@@ -185,6 +185,15 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called gspca_sq905.
 
+config USB_GSPCA_SQ905C
+	tristate "SQ Technologies SQ905C based USB Camera Driver"
+	depends on VIDEO_V4L2 && USB_GSPCA
+	help
+	  Say Y here if you want support for cameras based on the SQ905C chip.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called gspca_sq905c.
+
 config USB_GSPCA_STK014
 	tristate "Syntek DV4000 (STK014) USB Camera Driver"
 	depends on VIDEO_V4L2 && USB_GSPCA
diff --git a/drivers/media/video/gspca/Makefile b/drivers/media/video/gspca/Makefile
index b6ec611..8a6643e 100644
--- a/drivers/media/video/gspca/Makefile
+++ b/drivers/media/video/gspca/Makefile
@@ -17,6 +17,7 @@
 obj-$(CONFIG_USB_GSPCA_SPCA508)  += gspca_spca508.o
 obj-$(CONFIG_USB_GSPCA_SPCA561)  += gspca_spca561.o
 obj-$(CONFIG_USB_GSPCA_SQ905)    += gspca_sq905.o
+obj-$(CONFIG_USB_GSPCA_SQ905C)   += gspca_sq905c.o
 obj-$(CONFIG_USB_GSPCA_SUNPLUS)  += gspca_sunplus.o
 obj-$(CONFIG_USB_GSPCA_STK014)   += gspca_stk014.o
 obj-$(CONFIG_USB_GSPCA_T613)     += gspca_t613.o
@@ -43,6 +44,7 @@
 gspca_spca508-objs  := spca508.o
 gspca_spca561-objs  := spca561.o
 gspca_sq905-objs    := sq905.o
+gspca_sq905c-objs   := sq905c.o
 gspca_stk014-objs   := stk014.o
 gspca_sunplus-objs  := sunplus.o
 gspca_t613-objs     := t613.o
diff --git a/drivers/media/video/gspca/sq905c.c b/drivers/media/video/gspca/sq905c.c
new file mode 100644
index 0000000..0bcb74a
--- /dev/null
+++ b/drivers/media/video/gspca/sq905c.c
@@ -0,0 +1,328 @@
+/*
+ * SQ905C subdriver
+ *
+ * Copyright (C) 2009 Theodore Kilgore
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ *
+ * This driver uses work done in
+ * libgphoto2/camlibs/digigr8, Copyright (C) Theodore Kilgore.
+ *
+ * This driver has also used as a base the sq905c driver
+ * and may contain code fragments from it.
+ */
+
+#define MODULE_NAME "sq905c"
+
+#include <linux/workqueue.h>
+#include "gspca.h"
+
+MODULE_AUTHOR("Theodore Kilgore <kilgota@auburn.edu>");
+MODULE_DESCRIPTION("GSPCA/SQ905C USB Camera Driver");
+MODULE_LICENSE("GPL");
+
+/* Default timeouts, in ms */
+#define SQ905C_CMD_TIMEOUT 500
+#define SQ905C_DATA_TIMEOUT 1000
+
+/* Maximum transfer size to use. */
+#define SQ905C_MAX_TRANSFER 0x8000
+
+#define FRAME_HEADER_LEN 0x50
+
+/* Commands. These go in the "value" slot. */
+#define SQ905C_CLEAR   0xa0		/* clear everything */
+#define SQ905C_CAPTURE_LOW 0xa040	/* Starts capture at 160x120 */
+#define SQ905C_CAPTURE_MED 0x1440	/* Starts capture at 320x240 */
+#define SQ905C_CAPTURE_HI 0x2840	/* Starts capture at 320x240 */
+
+/* For capture, this must go in the "index" slot. */
+#define SQ905C_CAPTURE_INDEX 0x110f
+
+/* Structure to hold all of our device specific stuff */
+struct sd {
+	struct gspca_dev gspca_dev;	/* !! must be the first item */
+	const struct v4l2_pix_format *cap_mode;
+	/* Driver stuff */
+	struct work_struct work_struct;
+	struct workqueue_struct *work_thread;
+};
+
+/*
+ * Most of these cameras will do 640x480 and 320x240. 160x120 works
+ * in theory but gives very poor output. Therefore, not supported.
+ * The 0x2770:0x9050 cameras have max resolution of 320x240.
+ */
+static struct v4l2_pix_format sq905c_mode[] = {
+	{ 320, 240, V4L2_PIX_FMT_SQ905C, V4L2_FIELD_NONE,
+		.bytesperline = 320,
+		.sizeimage = 320 * 240,
+		.colorspace = V4L2_COLORSPACE_SRGB,
+		.priv = 0},
+	{ 640, 480, V4L2_PIX_FMT_SQ905C, V4L2_FIELD_NONE,
+		.bytesperline = 640,
+		.sizeimage = 640 * 480,
+		.colorspace = V4L2_COLORSPACE_SRGB,
+		.priv = 0}
+};
+
+/* Send a command to the camera. */
+static int sq905c_command(struct gspca_dev *gspca_dev, u16 command, u16 index)
+{
+	int ret;
+
+	ret = usb_control_msg(gspca_dev->dev,
+			      usb_sndctrlpipe(gspca_dev->dev, 0),
+			      USB_REQ_SYNCH_FRAME,                /* request */
+			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+			      command, index, NULL, 0,
+			      SQ905C_CMD_TIMEOUT);
+	if (ret < 0) {
+		PDEBUG(D_ERR, "%s: usb_control_msg failed (%d)",
+			__func__, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+/* This function is called as a workqueue function and runs whenever the camera
+ * is streaming data. Because it is a workqueue function it is allowed to sleep
+ * so we can use synchronous USB calls. To avoid possible collisions with other
+ * threads attempting to use the camera's USB interface the gspca usb_lock is
+ * used when performing the one USB control operation inside the workqueue,
+ * which tells the camera to close the stream. In practice the only thing
+ * which needs to be protected against is the usb_set_interface call that
+ * gspca makes during stream_off. Otherwise the camera doesn't provide any
+ * controls that the user could try to change.
+ */
+static void sq905c_dostream(struct work_struct *work)
+{
+	struct sd *dev = container_of(work, struct sd, work_struct);
+	struct gspca_dev *gspca_dev = &dev->gspca_dev;
+	struct gspca_frame *frame;
+	int bytes_left; /* bytes remaining in current frame. */
+	int data_len;   /* size to use for the next read. */
+	int act_len;
+	int discarding = 0; /* true if we failed to get space for frame. */
+	int packet_type;
+	int ret;
+	u8 *buffer;
+
+	buffer = kmalloc(SQ905C_MAX_TRANSFER, GFP_KERNEL | GFP_DMA);
+	if (!buffer) {
+		PDEBUG(D_ERR, "Couldn't allocate USB buffer");
+		goto quit_stream;
+	}
+
+	while (gspca_dev->present && gspca_dev->streaming) {
+		if (!gspca_dev->present)
+			goto quit_stream;
+		/* Request the header, which tells the size to download */
+		ret = usb_bulk_msg(gspca_dev->dev,
+				usb_rcvbulkpipe(gspca_dev->dev, 0x81),
+				buffer, FRAME_HEADER_LEN, &act_len,
+				SQ905C_DATA_TIMEOUT);
+		PDEBUG(D_STREAM,
+			"Got %d bytes out of %d for header",
+			act_len, FRAME_HEADER_LEN);
+		if (ret < 0 || act_len < FRAME_HEADER_LEN)
+			goto quit_stream;
+		/* size is read from 4 bytes starting 0x40, little endian */
+		bytes_left = buffer[0x40]|(buffer[0x41]<<8)|(buffer[0x42]<<16)
+					|(buffer[0x43]<<24);
+		PDEBUG(D_STREAM, "bytes_left = 0x%x", bytes_left);
+		/* We keep the header. It has other information, too. */
+		packet_type = FIRST_PACKET;
+		frame = gspca_get_i_frame(gspca_dev);
+		if (frame && !discarding) {
+			gspca_frame_add(gspca_dev, packet_type,
+				frame, buffer, FRAME_HEADER_LEN);
+			} else
+				discarding = 1;
+		while (bytes_left > 0) {
+			data_len = bytes_left > SQ905C_MAX_TRANSFER ?
+				SQ905C_MAX_TRANSFER : bytes_left;
+			if (!gspca_dev->present)
+				goto quit_stream;
+			ret = usb_bulk_msg(gspca_dev->dev,
+				usb_rcvbulkpipe(gspca_dev->dev, 0x81),
+				buffer, data_len, &act_len,
+				SQ905C_DATA_TIMEOUT);
+			if (ret < 0 || act_len < data_len)
+				goto quit_stream;
+			PDEBUG(D_STREAM,
+				"Got %d bytes out of %d for frame",
+				data_len, bytes_left);
+			bytes_left -= data_len;
+			if (bytes_left == 0)
+				packet_type = LAST_PACKET;
+			else
+				packet_type = INTER_PACKET;
+			frame = gspca_get_i_frame(gspca_dev);
+			if (frame && !discarding)
+				gspca_frame_add(gspca_dev, packet_type,
+						frame, buffer, data_len);
+			else
+				discarding = 1;
+		}
+	}
+quit_stream:
+	mutex_lock(&gspca_dev->usb_lock);
+	if (gspca_dev->present)
+		sq905c_command(gspca_dev, SQ905C_CLEAR, 0);
+	mutex_unlock(&gspca_dev->usb_lock);
+	kfree(buffer);
+}
+
+/* This function is called at probe time just before sd_init */
+static int sd_config(struct gspca_dev *gspca_dev,
+		const struct usb_device_id *id)
+{
+	struct cam *cam = &gspca_dev->cam;
+	struct sd *dev = (struct sd *) gspca_dev;
+
+	PDEBUG(D_PROBE,
+		"SQ9050 camera detected"
+		" (vid/pid 0x%04X:0x%04X)", id->idVendor, id->idProduct);
+	cam->cam_mode = sq905c_mode;
+	cam->nmodes = 2;
+	if (id->idProduct == 0x9050)
+		cam->nmodes = 1;
+	/* We don't use the buffer gspca allocates so make it small. */
+	cam->bulk_size = 32;
+	INIT_WORK(&dev->work_struct, sq905c_dostream);
+	return 0;
+}
+
+/* called on streamoff with alt==0 and on disconnect */
+/* the usb_lock is held at entry - restore on exit */
+static void sd_stop0(struct gspca_dev *gspca_dev)
+{
+	struct sd *dev = (struct sd *) gspca_dev;
+
+	/* wait for the work queue to terminate */
+	mutex_unlock(&gspca_dev->usb_lock);
+	/* This waits for sq905c_dostream to finish */
+	destroy_workqueue(dev->work_thread);
+	dev->work_thread = NULL;
+	mutex_lock(&gspca_dev->usb_lock);
+}
+
+/* this function is called at probe and resume time */
+static int sd_init(struct gspca_dev *gspca_dev)
+{
+	int ret;
+
+	/* connect to the camera and reset it. */
+	ret = sq905c_command(gspca_dev, SQ905C_CLEAR, 0);
+	return ret;
+}
+
+/* Set up for getting frames. */
+static int sd_start(struct gspca_dev *gspca_dev)
+{
+	struct sd *dev = (struct sd *) gspca_dev;
+	int ret;
+
+	dev->cap_mode = gspca_dev->cam.cam_mode;
+	/* "Open the shutter" and set size, to start capture */
+	switch (gspca_dev->width) {
+	case 640:
+		PDEBUG(D_STREAM, "Start streaming at high resolution");
+		dev->cap_mode++;
+		ret = sq905c_command(gspca_dev, SQ905C_CAPTURE_HI,
+						SQ905C_CAPTURE_INDEX);
+		break;
+	default: /* 320 */
+	PDEBUG(D_STREAM, "Start streaming at medium resolution");
+		ret = sq905c_command(gspca_dev, SQ905C_CAPTURE_MED,
+						SQ905C_CAPTURE_INDEX);
+	}
+
+	if (ret < 0) {
+		PDEBUG(D_ERR, "Start streaming command failed");
+		return ret;
+	}
+	/* Start the workqueue function to do the streaming */
+	dev->work_thread = create_singlethread_workqueue(MODULE_NAME);
+	queue_work(dev->work_thread, &dev->work_struct);
+
+	return 0;
+}
+
+/* Table of supported USB devices */
+static const __devinitdata struct usb_device_id device_table[] = {
+	{USB_DEVICE(0x2770, 0x905c)},
+	{USB_DEVICE(0x2770, 0x9050)},
+	{USB_DEVICE(0x2770, 0x913d)},
+	{}
+};
+
+MODULE_DEVICE_TABLE(usb, device_table);
+
+/* sub-driver description */
+static const struct sd_desc sd_desc = {
+	.name   = MODULE_NAME,
+	.config = sd_config,
+	.init   = sd_init,
+	.start  = sd_start,
+	.stop0  = sd_stop0,
+};
+
+/* -- device connect -- */
+static int sd_probe(struct usb_interface *intf,
+		const struct usb_device_id *id)
+{
+	return gspca_dev_probe(intf, id,
+			&sd_desc,
+			sizeof(struct sd),
+			THIS_MODULE);
+}
+
+static struct usb_driver sd_driver = {
+	.name       = MODULE_NAME,
+	.id_table   = device_table,
+	.probe      = sd_probe,
+	.disconnect = gspca_disconnect,
+#ifdef CONFIG_PM
+	.suspend = gspca_suspend,
+	.resume  = gspca_resume,
+#endif
+};
+
+/* -- module insert / remove -- */
+static int __init sd_mod_init(void)
+{
+	int ret;
+
+	ret = usb_register(&sd_driver);
+	if (ret < 0)
+		return ret;
+	PDEBUG(D_PROBE, "registered");
+	return 0;
+}
+
+static void __exit sd_mod_exit(void)
+{
+	usb_deregister(&sd_driver);
+	PDEBUG(D_PROBE, "deregistered");
+}
+
+module_init(sd_mod_init);
+module_exit(sd_mod_exit);
diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 61f1a49..139d234 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -345,6 +345,7 @@
 #define V4L2_PIX_FMT_SPCA561  v4l2_fourcc('S', '5', '6', '1') /* compressed GBRG bayer */
 #define V4L2_PIX_FMT_PAC207   v4l2_fourcc('P', '2', '0', '7') /* compressed BGGR bayer */
 #define V4L2_PIX_FMT_MR97310A v4l2_fourcc('M', '3', '1', '0') /* compressed BGGR bayer */
+#define V4L2_PIX_FMT_SQ905C   v4l2_fourcc('9', '0', '5', 'C') /* compressed RGGB bayer */
 #define V4L2_PIX_FMT_PJPG     v4l2_fourcc('P', 'J', 'P', 'G') /* Pixart 73xx JPEG */
 #define V4L2_PIX_FMT_YVYU    v4l2_fourcc('Y', 'V', 'Y', 'U') /* 16  YVU 4:2:2     */