[PATCH] add bt832 module

This adds a driver module for the bt832 chip.  It is needed by the bttv
driver to support the Pixelview Digital Camera.  The bt832 is connected
using the GPIO pins of the bt878 chip.

drivers/media/video/bt832.c

+/* Driver for Bt832 CMOS Camera Video Processor
+    i2c-adresses: 0x88 or 0x8a
+
+  The BT832 interfaces to a Quartzsight Digital Camera (352x288, 25 or 30 fps)
+  via a 9 pin connector ( 4-wire SDATA, 2-wire i2c, SCLK, VCC, GND).
+  It outputs an 8-bit 4:2:2 YUV or YCrCb video signal which can be directly
+  connected to bt848/bt878 GPIO pins on this purpose.
+  (see: VLSI Vision Ltd. www.vvl.co.uk for camera datasheets)
+  
+  Supported Cards:
+  -  Pixelview Rev.4E: 0x8a
+		GPIO 0x400000 toggles Bt832 RESET, and the chip changes to i2c 0x88 !
+
+  (c) Gunther Mayer, 2002
+
+  STATUS:
+  - detect chip and hexdump
+  - reset chip and leave low power mode
+  - detect camera present
+
+  TODO:
+  - make it work (find correct setup for Bt832 and Bt878)
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/types.h>
+#include <linux/videodev.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+
+#include "id.h"
+#include "audiochip.h"
+#include "bttv.h"
+#include "bt832.h"
+
+MODULE_LICENSE("GPL");
+
+/* Addresses to scan */
+static unsigned short normal_i2c[] = {I2C_CLIENT_END};
+static unsigned short normal_i2c_range[] = {I2C_BT832_ALT1>>1,I2C_BT832_ALT2>>1,I2C_CLIENT_END};
+I2C_CLIENT_INSMOD;
+
+/* ---------------------------------------------------------------------- */
+
+#define dprintk     if (debug) printk
+
+static int bt832_detach(struct i2c_client *client);
+
+
+static struct i2c_driver driver;
+static struct i2c_client client_template;
+
+struct bt832 {
+        struct i2c_client client;
+};
+
+int bt832_hexdump(struct i2c_client *i2c_client_s, unsigned char *buf)
+{
+	int i,rc;
+	buf[0]=0x80; // start at register 0 with auto-increment
+        if (1 != (rc = i2c_master_send(i2c_client_s,buf,1)))
+                printk("bt832: i2c i/o error: rc == %d (should be 1)\n",rc);
+
+        for(i=0;i<65;i++)
+                buf[i]=0;
+        if (65 != (rc=i2c_master_recv(i2c_client_s,buf,65)))
+                printk("bt832: i2c i/o error: rc == %d (should be 65)\n",rc);
+
+        // Note: On READ the first byte is the current index
+        //  (e.g. 0x80, what we just wrote)
+
+        if(1) {
+                int i;
+                printk("BT832 hexdump:\n");
+                for(i=1;i<65;i++) {
+			if(i!=1) {
+			  if(((i-1)%8)==0) printk(" ");
+                          if(((i-1)%16)==0) printk("\n");
+			}
+                        printk(" %02x",buf[i]);
+                }
+                printk("\n");
+        }
+	return 0;
+}
+
+// Return: 1 (is a bt832), 0 (No bt832 here)
+int bt832_init(struct i2c_client *i2c_client_s)
+{
+	unsigned char *buf;
+	int rc;
+
+	buf=kmalloc(65,GFP_KERNEL);
+	bt832_hexdump(i2c_client_s,buf);
+	
+	if(buf[0x40] != 0x31) {
+		printk("bt832: this i2c chip is no bt832 (id=%02x). Detaching.\n",buf[0x40]);
+		kfree(buf);
+		return 0;
+	}
+
+        printk("Write 0 tp VPSTATUS\n");
+        buf[0]=BT832_VP_STATUS; // Reg.52
+        buf[1]= 0x00;
+        if (2 != (rc = i2c_master_send(i2c_client_s,buf,2)))
+                printk("bt832: i2c i/o error VPS: rc == %d (should be 2)\n",rc);
+
+        bt832_hexdump(i2c_client_s,buf);
+
+
+	// Leave low power mode:
+	printk("Bt832: leave low power mode.\n");
+	buf[0]=BT832_CAM_SETUP0; //0x39 57
+	buf[1]=0x08;
+	if (2 != (rc = i2c_master_send(i2c_client_s,buf,2)))
+                printk("bt832: i2c i/o error LLPM: rc == %d (should be 2)\n",rc);
+
+        bt832_hexdump(i2c_client_s,buf);
+
+	printk("Write 0 tp VPSTATUS\n");
+        buf[0]=BT832_VP_STATUS; // Reg.52
+        buf[1]= 0x00;
+        if (2 != (rc = i2c_master_send(i2c_client_s,buf,2)))
+                printk("bt832: i2c i/o error VPS: rc == %d (should be 2)\n",rc);
+
+        bt832_hexdump(i2c_client_s,buf);
+
+
+	// Enable Output
+	printk("Enable Output\n");
+	buf[0]=BT832_VP_CONTROL1; // Reg.40
+	buf[1]= 0x27 & (~0x01); // Default | !skip
+	if (2 != (rc = i2c_master_send(i2c_client_s,buf,2)))
+                printk("bt832: i2c i/o error EO: rc == %d (should be 2)\n",rc);
+	
+        bt832_hexdump(i2c_client_s,buf);
+
+#if 0
+	// Full 30/25 Frame rate
+	printk("Full 30/25 Frame rate\n");
+	buf[0]=BT832_VP_CONTROL0; // Reg.39
+        buf[1]= 0x00;
+        if (2 != (rc = i2c_master_send(i2c_client_s,buf,2)))
+                printk("bt832: i2c i/o error FFR: rc == %d (should be 2)\n",rc);
+
+        bt832_hexdump(i2c_client_s,buf);
+#endif
+
+#if 1
+	// for testing (even works when no camera attached)
+	printk("bt832: *** Generate NTSC M Bars *****\n");
+	buf[0]=BT832_VP_TESTCONTROL0; // Reg. 42
+	buf[1]=3; // Generate NTSC System M bars, Generate Frame timing internally
+        if (2 != (rc = i2c_master_send(i2c_client_s,buf,2)))
+                printk("bt832: i2c i/o error MBAR: rc == %d (should be 2)\n",rc);
+#endif
+
+	printk("Bt832: Camera Present: %s\n",
+		(buf[1+BT832_CAM_STATUS] & BT832_56_CAMERA_PRESENT) ? "yes":"no");
+
+        bt832_hexdump(i2c_client_s,buf);
+	kfree(buf);
+	return 1;
+}
+
+
+
+static int bt832_attach(struct i2c_adapter *adap, int addr,
+			  unsigned short flags, int kind)
+{
+	struct bt832 *t;
+
+	printk("bt832_attach\n");
+
+        client_template.adapter = adap;
+        client_template.addr    = addr;
+
+        printk("bt832: chip found @ 0x%x\n", addr<<1);
+
+        if (NULL == (t = kmalloc(sizeof(*t), GFP_KERNEL)))
+                return -ENOMEM;
+	memset(t,0,sizeof(*t));
+	t->client = client_template;
+        t->client.data = t;
+        i2c_attach_client(&t->client);
+
+	MOD_INC_USE_COUNT;
+	if(! bt832_init(&t->client)) {
+		bt832_detach(&t->client);
+		return -1;
+	}
+        
+	return 0;
+}
+
+static int bt832_probe(struct i2c_adapter *adap)
+{
+	int rc;
+
+	printk("bt832_probe\n");
+
+	switch (adap->id) {
+	case I2C_ALGO_BIT | I2C_HW_B_BT848:
+	case I2C_ALGO_BIT | I2C_HW_B_RIVA:
+	case I2C_ALGO_SAA7134:
+		printk("bt832: probing %s i2c adapter [id=0x%x]\n",
+		       adap->name,adap->id);
+		rc = i2c_probe(adap, &addr_data, bt832_attach);
+		break;
+	default:
+		printk("bt832: ignoring %s i2c adapter [id=0x%x]\n",
+		       adap->name,adap->id);
+		rc = 0;
+		/* nothing */
+	}
+	return rc;
+}
+
+static int bt832_detach(struct i2c_client *client)
+{
+	struct bt832 *t = (struct bt832*)client->data;
+
+	printk("bt832: detach.\n");
+	i2c_detach_client(client);
+	kfree(t);
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+static int
+bt832_command(struct i2c_client *client, unsigned int cmd, void *arg)
+{
+	struct bt832 *t = (struct bt832*)client->data;
+
+	printk("bt832: command %x\n",cmd);
+
+        switch (cmd) {
+		case BT832_HEXDUMP: {
+			unsigned char *buf;
+			buf=kmalloc(65,GFP_KERNEL);
+			bt832_hexdump(&t->client,buf);
+			kfree(buf);
+		}
+		break;
+		case BT832_REATTACH:
+			printk("bt832: re-attach\n");
+			i2c_del_driver(&driver);
+			i2c_add_driver(&driver);
+		break;
+	}
+	return 0;
+}
+
+/* ----------------------------------------------------------------------- */
+
+static struct i2c_driver driver = {
+	.owner          = THIS_MODULE,
+        .name           = "i2c bt832 driver",
+        .id             = -1, /* FIXME */
+        .flags          = I2C_DF_NOTIFY,
+        .attach_adapter = bt832_probe,
+        .detach_client  = bt832_detach,
+        .command        = bt832_command,
+};
+static struct i2c_client client_template =
+{
+        .name   = "bt832",
+	.flags  = I2C_CLIENT_ALLOW_USE,
+        .driver = &driver,
+};
+
+
+int bt832_init_module(void)
+{
+	i2c_add_driver(&driver);
+	return 0;
+}
+
+static void bt832_cleanup_module(void)
+{
+	i2c_del_driver(&driver);
+}
+
+module_init(bt832_init_module);
+module_exit(bt832_cleanup_module);
+