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 00000000000..b2ba9dc0dd6
--- /dev/null
+++ b/drivers/media/common/saa7146_i2c.c
@@ -0,0 +1,421 @@
+#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, __le32 *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(__le32)*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] |= cpu_to_le32(      (u8)addr << ((3-h2)*8));
+                op[h1] |= cpu_to_le32(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] |= cpu_to_le32( (u32)((u8)m[i].buf[j]) << ((3-h2)*8));
+                        op[h1] |= cpu_to_le32(       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 & (le32_to_cpu(op[h1]) >> ((3-h2)*2))) ) {
+                op[h1] &= ~cpu_to_le32(0x2 << ((3-h2)*2));
+                op[h1] |= cpu_to_le32(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, __le32 *op)
+{
+        int i, j;
+        int op_count = 0;
+
+        /* loop through all messages */
+        for(i = 0; i < num; i++) {
+
+                op_count++;
+
+                /* loop through 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] = (le32_to_cpu(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 occurred ... */
+        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, __le32 *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, le32_to_cpu(*dword));
+
+                dev->i2c_op = 1;
+                SAA7146_ISR_CLEAR(dev, MASK_16|MASK_17);
+                SAA7146_IER_ENABLE(dev, MASK_16|MASK_17);
+                saa7146_write(dev, MC2, (MASK_00 | MASK_16));
+
+                timeout = HZ/100 + 1; /* 10ms */
+                timeout = wait_event_interruptible_timeout(dev->i2c_wq, dev->i2c_op == 0, timeout);
+                if (timeout == -ERESTARTSYS || dev->i2c_op) {
+                        SAA7146_IER_DISABLE(dev, MASK_16|MASK_17);
+                        SAA7146_ISR_CLEAR(dev, MASK_16|MASK_17);
+                        if (timeout == -ERESTARTSYS)
+                                /* a signal arrived */
+                                return -ERESTARTSYS;
+
+                        printk(KERN_WARNING "%s %s [irq]: timed out waiting for end of xfer\n",
+                                dev->name, __func__);
+                        return -EIO;
+                }
+                status = saa7146_read(dev, I2C_STATUS);
+        } else {
+                saa7146_write(dev, I2C_STATUS,   dev->i2c_bitrate);
+                saa7146_write(dev, I2C_TRANSFER, le32_to_cpu(*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 "%s %s: timed out waiting for MC2\n",
+                                        dev->name, __func__);
+                                return -EIO;
+                        }
+                }
+                /* wait until we get a transfer done or error */
+                timeout = jiffies + HZ/100 + 1; /* 10ms */
+                /* first read usually delivers bogus results... */
+                saa7146_i2c_status(dev);
+                while(1) {
+                        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...)
+                                 */
+                                printk(KERN_WARNING "%s %s [poll]: timed out waiting for end of xfer\n",
+                                        dev->name, __func__);
+                                return -EIO;
+                        }
+                        if (++trial < 50 && short_delay)
+                                udelay(10);
+                        else
+                                msleep(1);
+                }
+        }
+
+        /* give a detailed status report */
+        if ( 0 != (status & (SAA7146_I2C_SPERR | SAA7146_I2C_APERR |
+                             SAA7146_I2C_DTERR | SAA7146_I2C_DRERR |
+                             SAA7146_I2C_AL    | SAA7146_I2C_ERR   |
+                             SAA7146_I2C_BUSY)) ) {
+
+                if ( 0 == (status & SAA7146_I2C_ERR) ||
+                     0 == (status & SAA7146_I2C_BUSY) ) {
+                        /* it may take some time until ERR goes high - ignore */
+                        DEB_I2C(("unexpected i2c status %04x\n", status));
+                }
+                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 = cpu_to_le32(saa7146_read(dev, I2C_TRANSFER));
+
+        DEB_I2C(("after: 0x%08x\n",*dword));
+        return 0;
+}
+
+static int saa7146_i2c_transfer(struct saa7146_dev *dev, const struct i2c_msg *msgs, int num, int retries)
+{
+        int i = 0, count = 0;
+        __le32 *buffer = dev->d_i2c.cpu_addr;
+        int err = 0;
+        int short_delay = 0;
+
+        if (mutex_lock_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 occurred. in that case, the
+                                   transaction should be retrying, even if an address error
+                                   occurred. 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. So we bail out in irq mode after an
+                                   address error and trust the saa7146 address error detection. */
+                                if (-EREMOTEIO == err && 0 != (SAA7146_USE_I2C_IRQ & dev->ext->flags))
+                                        goto out;
+                                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--);
+
+        /* quit if any error occurred */
+        if (err != num)
+                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 continuing */
+        if( 0 == dev->revision ) {
+                __le32 zero = 0;
+                saa7146_i2c_reset(dev);
+                if( 0 != saa7146_i2c_writeout(dev, &zero, short_delay)) {
+                        INFO(("revision 0 error. this should never happen.\n"));
+                }
+        }
+
+        mutex_unlock(&dev->i2c_lock);
+        return err;
+}
+
+/* utility functions */
+static int saa7146_i2c_xfer(struct i2c_adapter* adapter, struct i2c_msg *msg, int num)
+{
+        struct v4l2_device *v4l2_dev = i2c_get_adapdata(adapter);
+        struct saa7146_dev *dev = to_saa7146_dev(v4l2_dev);
+
+        /* use helper function to transfer data */
+        return saa7146_i2c_transfer(dev, msg, num, adapter->retries);
+}
+
+
+/*****************************************************************************/
+/* i2c-adapter helper functions                                              */
+
+/* exported algorithm data */
+static struct i2c_algorithm saa7146_algo = {
+        .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 (i2c_adapter) {
+                i2c_set_adapdata(i2c_adapter, &dev->v4l2_dev);
+                i2c_adapter->dev.parent    = &dev->pci->dev;
+                i2c_adapter->algo          = &saa7146_algo;
+                i2c_adapter->algo_data     = NULL;
+                i2c_adapter->timeout = SAA7146_I2C_TIMEOUT;
+                i2c_adapter->retries = SAA7146_I2C_RETRIES;
+        }
+
+        return 0;
+}