Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 421 insertions, 0 deletions

diff --git a/drivers/media/common/saa7146_i2c.c b/drivers/media/common/saa7146_i2c.c
new file mode 100644
index 0000000..781f23f
--- /dev/null
+++ b/drivers/media/common/saa7146_i2c.c
@@ -0,0 +1,421 @@
+#include <linux/version.h>
+#include <media/saa7146_vv.h>
+
+static u32 saa7146_i2c_func(struct i2c_adapter *adapter)
+{
+//fm	DEB_I2C(("'%s'.\n", adapter->name));
+
+	return	  I2C_FUNC_I2C
+		| I2C_FUNC_SMBUS_QUICK
+		| I2C_FUNC_SMBUS_READ_BYTE	| I2C_FUNC_SMBUS_WRITE_BYTE
+		| I2C_FUNC_SMBUS_READ_BYTE_DATA | I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
+}
+
+/* this function returns the status-register of our i2c-device */
+static inline u32 saa7146_i2c_status(struct saa7146_dev *dev)
+{
+	u32 iicsta = saa7146_read(dev, I2C_STATUS);
+/*
+	DEB_I2C(("status: 0x%08x\n",iicsta));
+*/
+	return iicsta;
+}
+
+/* this function runs through the i2c-messages and prepares the data to be
+   sent through the saa7146. have a look at the specifications p. 122 ff
+   to understand this. it returns the number of u32s to send, or -1
+   in case of an error. */
+static int saa7146_i2c_msg_prepare(const struct i2c_msg *m, int num, u32 *op)
+{
+	int h1, h2;
+	int i, j, addr;
+	int mem = 0, op_count = 0;
+
+	/* first determine size of needed memory */
+	for(i = 0; i < num; i++) {
+		mem += m[i].len + 1;
+	}
+
+	/* worst case: we need one u32 for three bytes to be send
+	   plus one extra byte to address the device */
+	mem = 1 + ((mem-1) / 3);
+
+	/* we assume that op points to a memory of at least SAA7146_I2C_MEM bytes
+	   size. if we exceed this limit... */
+	if ( (4*mem) > SAA7146_I2C_MEM ) {
+//fm		DEB_I2C(("cannot prepare i2c-message.\n"));
+		return -ENOMEM;
+	}
+
+	/* be careful: clear out the i2c-mem first */
+	memset(op,0,sizeof(u32)*mem);
+
+	/* loop through all messages */
+	for(i = 0; i < num; i++) {
+
+		/* insert the address of the i2c-slave.
+		   note: we get 7 bit i2c-addresses,
+		   so we have to perform a translation */
+		addr = (m[i].addr*2) + ( (0 != (m[i].flags & I2C_M_RD)) ? 1 : 0);
+		h1 = op_count/3; h2 = op_count%3;
+		op[h1] |= (	    (u8)addr << ((3-h2)*8));
+		op[h1] |= (SAA7146_I2C_START << ((3-h2)*2));
+		op_count++;
+
+		/* loop through all bytes of message i */
+		for(j = 0; j < m[i].len; j++) {
+			/* insert the data bytes */
+			h1 = op_count/3; h2 = op_count%3;
+			op[h1] |= ( (u32)((u8)m[i].buf[j]) << ((3-h2)*8));
+			op[h1] |= (       SAA7146_I2C_CONT << ((3-h2)*2));
+			op_count++;
+		}
+
+	}
+
+	/* have a look at the last byte inserted:
+	  if it was: ...CONT change it to ...STOP */
+	h1 = (op_count-1)/3; h2 = (op_count-1)%3;
+	if ( SAA7146_I2C_CONT == (0x3 & (op[h1] >> ((3-h2)*2))) ) {
+		op[h1] &= ~(0x2 << ((3-h2)*2));
+		op[h1] |= (SAA7146_I2C_STOP << ((3-h2)*2));
+	}
+
+	/* return the number of u32s to send */
+	return mem;
+}
+
+/* this functions loops through all i2c-messages. normally, it should determine
+   which bytes were read through the adapter and write them back to the corresponding
+   i2c-message. but instead, we simply write back all bytes.
+   fixme: this could be improved. */
+static int saa7146_i2c_msg_cleanup(const struct i2c_msg *m, int num, u32 *op)
+{
+	int i, j;
+	int op_count = 0;
+
+	/* loop through all messages */
+	for(i = 0; i < num; i++) {
+
+		op_count++;
+
+		/* loop throgh all bytes of message i */
+		for(j = 0; j < m[i].len; j++) {
+			/* write back all bytes that could have been read */
+			m[i].buf[j] = (op[op_count/3] >> ((3-(op_count%3))*8));
+			op_count++;
+		}
+	}
+
+	return 0;
+}
+
+/* this functions resets the i2c-device and returns 0 if everything was fine, otherwise -1 */
+static int saa7146_i2c_reset(struct saa7146_dev *dev)
+{
+	/* get current status */
+	u32 status = saa7146_i2c_status(dev);
+
+	/* clear registers for sure */
+	saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate);
+	saa7146_write(dev, I2C_TRANSFER, 0);
+
+	/* check if any operation is still in progress */
+	if ( 0 != ( status & SAA7146_I2C_BUSY) ) {
+
+		/* yes, kill ongoing operation */
+		DEB_I2C(("busy_state detected.\n"));
+
+		/* set "ABORT-OPERATION"-bit (bit 7)*/
+		saa7146_write(dev, I2C_STATUS, (dev->i2c_bitrate | MASK_07));
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+		msleep(SAA7146_I2C_DELAY);
+
+		/* clear all error-bits pending; this is needed because p.123, note 1 */
+		saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate);
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+		msleep(SAA7146_I2C_DELAY);
+	}
+
+	/* check if any error is (still) present. (this can be necessary because p.123, note 1) */
+	status = saa7146_i2c_status(dev);
+
+	if ( dev->i2c_bitrate != status ) {
+
+		DEB_I2C(("error_state detected. status:0x%08x\n",status));
+
+		/* Repeat the abort operation. This seems to be necessary
+		   after serious protocol errors caused by e.g. the SAA7740 */
+		saa7146_write(dev, I2C_STATUS, (dev->i2c_bitrate | MASK_07));
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+		msleep(SAA7146_I2C_DELAY);
+
+		/* clear all error-bits pending */
+		saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate);
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+		msleep(SAA7146_I2C_DELAY);
+
+		/* the data sheet says it might be necessary to clear the status
+		   twice after an abort */
+		saa7146_write(dev, I2C_STATUS, dev->i2c_bitrate);
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+		msleep(SAA7146_I2C_DELAY);
+	}
+
+	/* if any error is still present, a fatal error has occured ... */
+	status = saa7146_i2c_status(dev);
+	if ( dev->i2c_bitrate != status ) {
+		DEB_I2C(("fatal error. status:0x%08x\n",status));
+		return -1;
+	}
+
+	return 0;
+}
+
+/* this functions writes out the data-byte 'dword' to the i2c-device.
+   it returns 0 if ok, -1 if the transfer failed, -2 if the transfer
+   failed badly (e.g. address error) */
+static int saa7146_i2c_writeout(struct saa7146_dev *dev, u32* dword, int short_delay)
+{
+	u32 status = 0, mc2 = 0;
+	int trial = 0;
+	unsigned long timeout;
+
+	/* write out i2c-command */
+	DEB_I2C(("before: 0x%08x (status: 0x%08x), %d\n",*dword,saa7146_read(dev, I2C_STATUS), dev->i2c_op));
+
+	if( 0 != (SAA7146_USE_I2C_IRQ & dev->ext->flags)) {
+
+		saa7146_write(dev, I2C_STATUS,	 dev->i2c_bitrate);
+		saa7146_write(dev, I2C_TRANSFER, *dword);
+
+		dev->i2c_op = 1;
+		SAA7146_IER_ENABLE(dev, MASK_16|MASK_17);
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+
+		wait_event_interruptible(dev->i2c_wq, dev->i2c_op == 0);
+		if (signal_pending (current)) {
+			/* a signal arrived */
+			return -ERESTARTSYS;
+		}
+		status = saa7146_read(dev, I2C_STATUS);
+	} else {
+		saa7146_write(dev, I2C_STATUS,	 dev->i2c_bitrate);
+		saa7146_write(dev, I2C_TRANSFER, *dword);
+		saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+
+		/* do not poll for i2c-status before upload is complete */
+		timeout = jiffies + HZ/100 + 1; /* 10ms */
+		while(1) {
+			mc2 = (saa7146_read(dev, MC2) & 0x1);
+			if( 0 != mc2 ) {
+				break;
+			}
+			if (time_after(jiffies,timeout)) {
+				printk(KERN_WARNING "saa7146_i2c_writeout: timed out waiting for MC2\n");
+				return -EIO;
+			}
+		}
+		/* wait until we get a transfer done or error */
+		timeout = jiffies + HZ/100 + 1; /* 10ms */
+		while(1) {
+			/**
+			 *  first read usually delivers bogus results...
+			 */
+			saa7146_i2c_status(dev);
+			status = saa7146_i2c_status(dev);
+			if ((status & 0x3) != 1)
+				break;
+			if (time_after(jiffies,timeout)) {
+				/* this is normal when probing the bus
+				 * (no answer from nonexisistant device...)
+				 */
+				DEB_I2C(("saa7146_i2c_writeout: timed out waiting for end of xfer\n"));
+				return -EIO;
+			}
+			if ((++trial < 20) && short_delay)
+				udelay(10);
+			else
+			msleep(1);
+		}
+	}
+
+	/* give a detailed status report */
+	if ( 0 != (status & SAA7146_I2C_ERR)) {
+
+		if( 0 != (status & SAA7146_I2C_SPERR) ) {
+			DEB_I2C(("error due to invalid start/stop condition.\n"));
+		}
+		if( 0 != (status & SAA7146_I2C_DTERR) ) {
+			DEB_I2C(("error in data transmission.\n"));
+		}
+		if( 0 != (status & SAA7146_I2C_DRERR) ) {
+			DEB_I2C(("error when receiving data.\n"));
+		}
+		if( 0 != (status & SAA7146_I2C_AL) ) {
+			DEB_I2C(("error because arbitration lost.\n"));
+		}
+
+		/* we handle address-errors here */
+		if( 0 != (status & SAA7146_I2C_APERR) ) {
+			DEB_I2C(("error in address phase.\n"));
+			return -EREMOTEIO;
+		}
+
+		return -EIO;
+	}
+
+	/* read back data, just in case we were reading ... */
+	*dword = saa7146_read(dev, I2C_TRANSFER);
+
+	DEB_I2C(("after: 0x%08x\n",*dword));
+	return 0;
+}
+
+int saa7146_i2c_transfer(struct saa7146_dev *dev, const struct i2c_msg *msgs, int num, int retries)
+{
+	int i = 0, count = 0;
+	u32* buffer = dev->d_i2c.cpu_addr;
+	int err = 0;
+        int address_err = 0;
+        int short_delay = 0;
+
+	if (down_interruptible (&dev->i2c_lock))
+		return -ERESTARTSYS;
+
+	for(i=0;i<num;i++) {
+		DEB_I2C(("msg:%d/%d\n",i+1,num));
+	}
+
+	/* prepare the message(s), get number of u32s to transfer */
+	count = saa7146_i2c_msg_prepare(msgs, num, buffer);
+	if ( 0 > count ) {
+		err = -1;
+		goto out;
+	}
+
+	if ( count > 3 || 0 != (SAA7146_I2C_SHORT_DELAY & dev->ext->flags) )
+		short_delay = 1;
+
+	do {
+		/* reset the i2c-device if necessary */
+		err = saa7146_i2c_reset(dev);
+		if ( 0 > err ) {
+			DEB_I2C(("could not reset i2c-device.\n"));
+			goto out;
+		}
+
+		/* write out the u32s one after another */
+		for(i = 0; i < count; i++) {
+			err = saa7146_i2c_writeout(dev, &buffer[i], short_delay);
+			if ( 0 != err) {
+				/* this one is unsatisfying: some i2c slaves on some
+				   dvb cards don't acknowledge correctly, so the saa7146
+				   thinks that an address error occured. in that case, the
+				   transaction should be retrying, even if an address error
+				   occured. analog saa7146 based cards extensively rely on
+				   i2c address probing, however, and address errors indicate that a
+				   device is really *not* there. retrying in that case
+				   increases the time the device needs to probe greatly, so
+				   it should be avoided. because of the fact, that only
+				   analog based cards use irq based i2c transactions (for dvb
+				   cards, this screwes up other interrupt sources), we bail out
+				   completely for analog cards after an address error and trust
+				   the saa7146 address error detection. */
+				if ( -EREMOTEIO == err ) {
+					if( 0 != (SAA7146_USE_I2C_IRQ & dev->ext->flags)) {
+						goto out;
+					}
+				        address_err++;
+				}
+				DEB_I2C(("error while sending message(s). starting again.\n"));
+				break;
+			}
+		}
+		if( 0 == err ) {
+			err = num;
+			break;
+		}
+
+	        /* delay a bit before retrying */
+	        msleep(10);
+
+	} while (err != num && retries--);
+
+        /* if every retry had an address error, exit right away */
+        if (address_err == retries) {
+	        goto out;
+	}
+
+	/* if any things had to be read, get the results */
+	if ( 0 != saa7146_i2c_msg_cleanup(msgs, num, buffer)) {
+		DEB_I2C(("could not cleanup i2c-message.\n"));
+		err = -1;
+		goto out;
+	}
+
+	/* return the number of delivered messages */
+	DEB_I2C(("transmission successful. (msg:%d).\n",err));
+out:
+	/* another bug in revision 0: the i2c-registers get uploaded randomly by other
+	   uploads, so we better clear them out before continueing */
+	if( 0 == dev->revision ) {
+		u32 zero = 0;
+		saa7146_i2c_reset(dev);
+		if( 0 != saa7146_i2c_writeout(dev, &zero, short_delay)) {
+			INFO(("revision 0 error. this should never happen.\n"));
+		}
+	}
+
+	up(&dev->i2c_lock);
+	return err;
+}
+
+/* utility functions */
+static int saa7146_i2c_xfer(struct i2c_adapter* adapter, struct i2c_msg *msg, int num)
+{
+	struct saa7146_dev* dev = i2c_get_adapdata(adapter);
+
+	/* use helper function to transfer data */
+	return saa7146_i2c_transfer(dev, msg, num, adapter->retries);
+}
+
+
+/*****************************************************************************/
+/* i2c-adapter helper functions                                              */
+#include <linux/i2c-id.h>
+
+/* exported algorithm data */
+static struct i2c_algorithm saa7146_algo = {
+	.name		= "saa7146 i2c algorithm",
+	.id		= I2C_ALGO_SAA7146,
+	.master_xfer	= saa7146_i2c_xfer,
+	.functionality	= saa7146_i2c_func,
+};
+
+int saa7146_i2c_adapter_prepare(struct saa7146_dev *dev, struct i2c_adapter *i2c_adapter, u32 bitrate)
+{
+	DEB_EE(("bitrate: 0x%08x\n",bitrate));
+
+	/* enable i2c-port pins */
+	saa7146_write(dev, MC1, (MASK_08 | MASK_24));
+
+	dev->i2c_bitrate = bitrate;
+	saa7146_i2c_reset(dev);
+
+	if( NULL != i2c_adapter ) {
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0))
+		i2c_adapter->data = dev;
+#else
+		BUG_ON(!i2c_adapter->class);
+		i2c_set_adapdata(i2c_adapter,dev);
+#endif
+		i2c_adapter->algo	   = &saa7146_algo;
+		i2c_adapter->algo_data     = NULL;
+		i2c_adapter->id		   = I2C_ALGO_SAA7146;
+		i2c_adapter->timeout = SAA7146_I2C_TIMEOUT;
+		i2c_adapter->retries = SAA7146_I2C_RETRIES;
+	}
+
+	return 0;
+}