This commit was manufactured by cvs2svn to create branch 'vserver'.
[linux-2.6.git] / drivers / i2c / busses / i2c-pnx.c
diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c
new file mode 100644 (file)
index 0000000..17376fe
--- /dev/null
@@ -0,0 +1,703 @@
+/*
+ * Provides I2C support for Philips PNX010x/PNX4008 boards.
+ *
+ * Authors: Dennis Kovalev <dkovalev@ru.mvista.com>
+ *         Vitaly Wool <vwool@ru.mvista.com>
+ *
+ * 2004-2006 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/timer.h>
+#include <linux/completion.h>
+#include <linux/platform_device.h>
+#include <linux/i2c-pnx.h>
+#include <asm/hardware.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+
+#define I2C_PNX_TIMEOUT                10 /* msec */
+#define I2C_PNX_SPEED_KHZ      100
+#define I2C_PNX_REGION_SIZE    0x100
+#define PNX_DEFAULT_FREQ       13 /* MHz */
+
+static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data)
+{
+       while (timeout > 0 &&
+                       (ioread32(I2C_REG_STS(data)) & mstatus_active)) {
+               mdelay(1);
+               timeout--;
+       }
+       return (timeout <= 0);
+}
+
+static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data)
+{
+       while (timeout > 0 &&
+                       (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) {
+               mdelay(1);
+               timeout--;
+       }
+       return (timeout <= 0);
+}
+
+static inline void i2c_pnx_arm_timer(struct i2c_adapter *adap)
+{
+       struct i2c_pnx_algo_data *data = adap->algo_data;
+       struct timer_list *timer = &data->mif.timer;
+       int expires = I2C_PNX_TIMEOUT / (1000 / HZ);
+
+       del_timer_sync(timer);
+
+       dev_dbg(&adap->dev, "Timer armed at %lu plus %u jiffies.\n",
+               jiffies, expires);
+
+       timer->expires = jiffies + expires;
+       timer->data = (unsigned long)adap;
+
+       add_timer(timer);
+}
+
+/**
+ * i2c_pnx_start - start a device
+ * @slave_addr:                slave address
+ * @adap:              pointer to adapter structure
+ *
+ * Generate a START signal in the desired mode.
+ */
+static int i2c_pnx_start(unsigned char slave_addr, struct i2c_adapter *adap)
+{
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+
+       dev_dbg(&adap->dev, "%s(): addr 0x%x mode %d\n", __FUNCTION__,
+               slave_addr, alg_data->mif.mode);
+
+       /* Check for 7 bit slave addresses only */
+       if (slave_addr & ~0x7f) {
+               dev_err(&adap->dev, "%s: Invalid slave address %x. "
+                      "Only 7-bit addresses are supported\n",
+                      adap->name, slave_addr);
+               return -EINVAL;
+       }
+
+       /* First, make sure bus is idle */
+       if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) {
+               /* Somebody else is monopolizing the bus */
+               dev_err(&adap->dev, "%s: Bus busy. Slave addr = %02x, "
+                      "cntrl = %x, stat = %x\n",
+                      adap->name, slave_addr,
+                      ioread32(I2C_REG_CTL(alg_data)),
+                      ioread32(I2C_REG_STS(alg_data)));
+               return -EBUSY;
+       } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) {
+               /* Sorry, we lost the bus */
+               dev_err(&adap->dev, "%s: Arbitration failure. "
+                      "Slave addr = %02x\n", adap->name, slave_addr);
+               return -EIO;
+       }
+
+       /*
+        * OK, I2C is enabled and we have the bus.
+        * Clear the current TDI and AFI status flags.
+        */
+       iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi,
+                 I2C_REG_STS(alg_data));
+
+       dev_dbg(&adap->dev, "%s(): sending %#x\n", __FUNCTION__,
+               (slave_addr << 1) | start_bit | alg_data->mif.mode);
+
+       /* Write the slave address, START bit and R/W bit */
+       iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode,
+                 I2C_REG_TX(alg_data));
+
+       dev_dbg(&adap->dev, "%s(): exit\n", __FUNCTION__);
+
+       return 0;
+}
+
+/**
+ * i2c_pnx_stop - stop a device
+ * @adap:              pointer to I2C adapter structure
+ *
+ * Generate a STOP signal to terminate the master transaction.
+ */
+static void i2c_pnx_stop(struct i2c_adapter *adap)
+{
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+       /* Only 1 msec max timeout due to interrupt context */
+       long timeout = 1000;
+
+       dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+
+       /* Write a STOP bit to TX FIFO */
+       iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data));
+
+       /* Wait until the STOP is seen. */
+       while (timeout > 0 &&
+              (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) {
+               /* may be called from interrupt context */
+               udelay(1);
+               timeout--;
+       }
+
+       dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+}
+
+/**
+ * i2c_pnx_master_xmit - transmit data to slave
+ * @adap:              pointer to I2C adapter structure
+ *
+ * Sends one byte of data to the slave
+ */
+static int i2c_pnx_master_xmit(struct i2c_adapter *adap)
+{
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+       u32 val;
+
+       dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+
+       if (alg_data->mif.len > 0) {
+               /* We still have something to talk about... */
+               val = *alg_data->mif.buf++;
+
+               if (alg_data->mif.len == 1) {
+                       val |= stop_bit;
+                       if (!alg_data->last)
+                               val |= start_bit;
+               }
+
+               alg_data->mif.len--;
+               iowrite32(val, I2C_REG_TX(alg_data));
+
+               dev_dbg(&adap->dev, "%s(): xmit %#x [%d]\n", __FUNCTION__,
+                       val, alg_data->mif.len + 1);
+
+               if (alg_data->mif.len == 0) {
+                       if (alg_data->last) {
+                               /* Wait until the STOP is seen. */
+                               if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
+                                       dev_err(&adap->dev, "The bus is still "
+                                               "active after timeout\n");
+                       }
+                       /* Disable master interrupts */
+                       iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
+                               ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
+                                 I2C_REG_CTL(alg_data));
+
+                       del_timer_sync(&alg_data->mif.timer);
+
+                       dev_dbg(&adap->dev, "%s(): Waking up xfer routine.\n",
+                               __FUNCTION__);
+
+                       complete(&alg_data->mif.complete);
+               }
+       } else if (alg_data->mif.len == 0) {
+               /* zero-sized transfer */
+               i2c_pnx_stop(adap);
+
+               /* Disable master interrupts. */
+               iowrite32(ioread32(I2C_REG_CTL(alg_data)) &
+                       ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie),
+                         I2C_REG_CTL(alg_data));
+
+               /* Stop timer. */
+               del_timer_sync(&alg_data->mif.timer);
+               dev_dbg(&adap->dev, "%s(): Waking up xfer routine after "
+                       "zero-xfer.\n", __FUNCTION__);
+
+               complete(&alg_data->mif.complete);
+       }
+
+       dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+
+       return 0;
+}
+
+/**
+ * i2c_pnx_master_rcv - receive data from slave
+ * @adap:              pointer to I2C adapter structure
+ *
+ * Reads one byte data from the slave
+ */
+static int i2c_pnx_master_rcv(struct i2c_adapter *adap)
+{
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+       unsigned int val = 0;
+       u32 ctl = 0;
+
+       dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+
+       /* Check, whether there is already data,
+        * or we didn't 'ask' for it yet.
+        */
+       if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
+               dev_dbg(&adap->dev, "%s(): Write dummy data to fill "
+                       "Rx-fifo...\n", __FUNCTION__);
+
+               if (alg_data->mif.len == 1) {
+                       /* Last byte, do not acknowledge next rcv. */
+                       val |= stop_bit;
+                       if (!alg_data->last)
+                               val |= start_bit;
+
+                       /*
+                        * Enable interrupt RFDAIE (data in Rx fifo),
+                        * and disable DRMIE (need data for Tx)
+                        */
+                       ctl = ioread32(I2C_REG_CTL(alg_data));
+                       ctl |= mcntrl_rffie | mcntrl_daie;
+                       ctl &= ~mcntrl_drmie;
+                       iowrite32(ctl, I2C_REG_CTL(alg_data));
+               }
+
+               /*
+                * Now we'll 'ask' for data:
+                * For each byte we want to receive, we must
+                * write a (dummy) byte to the Tx-FIFO.
+                */
+               iowrite32(val, I2C_REG_TX(alg_data));
+
+               return 0;
+       }
+
+       /* Handle data. */
+       if (alg_data->mif.len > 0) {
+               val = ioread32(I2C_REG_RX(alg_data));
+               *alg_data->mif.buf++ = (u8) (val & 0xff);
+               dev_dbg(&adap->dev, "%s(): rcv 0x%x [%d]\n", __FUNCTION__, val,
+                       alg_data->mif.len);
+
+               alg_data->mif.len--;
+               if (alg_data->mif.len == 0) {
+                       if (alg_data->last)
+                               /* Wait until the STOP is seen. */
+                               if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
+                                       dev_err(&adap->dev, "The bus is still "
+                                               "active after timeout\n");
+
+                       /* Disable master interrupts */
+                       ctl = ioread32(I2C_REG_CTL(alg_data));
+                       ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
+                                mcntrl_drmie | mcntrl_daie);
+                       iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+                       /* Kill timer. */
+                       del_timer_sync(&alg_data->mif.timer);
+                       complete(&alg_data->mif.complete);
+               }
+       }
+
+       dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+
+       return 0;
+}
+
+static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id)
+{
+       u32 stat, ctl;
+       struct i2c_adapter *adap = dev_id;
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+
+       dev_dbg(&adap->dev, "%s(): mstat = %x mctrl = %x, mode = %d\n",
+               __FUNCTION__,
+               ioread32(I2C_REG_STS(alg_data)),
+               ioread32(I2C_REG_CTL(alg_data)),
+               alg_data->mif.mode);
+       stat = ioread32(I2C_REG_STS(alg_data));
+
+       /* let's see what kind of event this is */
+       if (stat & mstatus_afi) {
+               /* We lost arbitration in the midst of a transfer */
+               alg_data->mif.ret = -EIO;
+
+               /* Disable master interrupts. */
+               ctl = ioread32(I2C_REG_CTL(alg_data));
+               ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
+                        mcntrl_drmie);
+               iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+               /* Stop timer, to prevent timeout. */
+               del_timer_sync(&alg_data->mif.timer);
+               complete(&alg_data->mif.complete);
+       } else if (stat & mstatus_nai) {
+               /* Slave did not acknowledge, generate a STOP */
+               dev_dbg(&adap->dev, "%s(): "
+                       "Slave did not acknowledge, generating a STOP.\n",
+                       __FUNCTION__);
+               i2c_pnx_stop(adap);
+
+               /* Disable master interrupts. */
+               ctl = ioread32(I2C_REG_CTL(alg_data));
+               ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
+                        mcntrl_drmie);
+               iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+               /* Our return value. */
+               alg_data->mif.ret = -EIO;
+
+               /* Stop timer, to prevent timeout. */
+               del_timer_sync(&alg_data->mif.timer);
+               complete(&alg_data->mif.complete);
+       } else {
+               /*
+                * Two options:
+                * - Master Tx needs data.
+                * - There is data in the Rx-fifo
+                * The latter is only the case if we have requested for data,
+                * via a dummy write. (See 'i2c_pnx_master_rcv'.)
+                * We therefore check, as a sanity check, whether that interrupt
+                * has been enabled.
+                */
+               if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) {
+                       if (alg_data->mif.mode == I2C_SMBUS_WRITE) {
+                               i2c_pnx_master_xmit(adap);
+                       } else if (alg_data->mif.mode == I2C_SMBUS_READ) {
+                               i2c_pnx_master_rcv(adap);
+                       }
+               }
+       }
+
+       /* Clear TDI and AFI bits */
+       stat = ioread32(I2C_REG_STS(alg_data));
+       iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data));
+
+       dev_dbg(&adap->dev, "%s(): exiting, stat = %x ctrl = %x.\n",
+                __FUNCTION__, ioread32(I2C_REG_STS(alg_data)),
+                ioread32(I2C_REG_CTL(alg_data)));
+
+       return IRQ_HANDLED;
+}
+
+static void i2c_pnx_timeout(unsigned long data)
+{
+       struct i2c_adapter *adap = (struct i2c_adapter *)data;
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+       u32 ctl;
+
+       dev_err(&adap->dev, "Master timed out. stat = %04x, cntrl = %04x. "
+              "Resetting master...\n",
+              ioread32(I2C_REG_STS(alg_data)),
+              ioread32(I2C_REG_CTL(alg_data)));
+
+       /* Reset master and disable interrupts */
+       ctl = ioread32(I2C_REG_CTL(alg_data));
+       ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie);
+       iowrite32(ctl, I2C_REG_CTL(alg_data));
+
+       ctl |= mcntrl_reset;
+       iowrite32(ctl, I2C_REG_CTL(alg_data));
+       wait_reset(I2C_PNX_TIMEOUT, alg_data);
+       alg_data->mif.ret = -EIO;
+       complete(&alg_data->mif.complete);
+}
+
+static inline void bus_reset_if_active(struct i2c_adapter *adap)
+{
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+       u32 stat;
+
+       if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) {
+               dev_err(&adap->dev,
+                       "%s: Bus is still active after xfer. Reset it...\n",
+                      adap->name);
+               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
+                         I2C_REG_CTL(alg_data));
+               wait_reset(I2C_PNX_TIMEOUT, alg_data);
+       } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) {
+               /* If there is data in the fifo's after transfer,
+                * flush fifo's by reset.
+                */
+               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
+                         I2C_REG_CTL(alg_data));
+               wait_reset(I2C_PNX_TIMEOUT, alg_data);
+       } else if (stat & mstatus_nai) {
+               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
+                         I2C_REG_CTL(alg_data));
+               wait_reset(I2C_PNX_TIMEOUT, alg_data);
+       }
+}
+
+/**
+ * i2c_pnx_xfer - generic transfer entry point
+ * @adap:              pointer to I2C adapter structure
+ * @msgs:              array of messages
+ * @num:               number of messages
+ *
+ * Initiates the transfer
+ */
+static int
+i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+       struct i2c_msg *pmsg;
+       int rc = 0, completed = 0, i;
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+       u32 stat = ioread32(I2C_REG_STS(alg_data));
+
+       dev_dbg(&adap->dev, "%s(): entering: %d messages, stat = %04x.\n",
+               __FUNCTION__, num, ioread32(I2C_REG_STS(alg_data)));
+
+       bus_reset_if_active(adap);
+
+       /* Process transactions in a loop. */
+       for (i = 0; rc >= 0 && i < num; i++) {
+               u8 addr;
+
+               pmsg = &msgs[i];
+               addr = pmsg->addr;
+
+               if (pmsg->flags & I2C_M_TEN) {
+                       dev_err(&adap->dev,
+                               "%s: 10 bits addr not supported!\n",
+                               adap->name);
+                       rc = -EINVAL;
+                       break;
+               }
+
+               alg_data->mif.buf = pmsg->buf;
+               alg_data->mif.len = pmsg->len;
+               alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ?
+                       I2C_SMBUS_READ : I2C_SMBUS_WRITE;
+               alg_data->mif.ret = 0;
+               alg_data->last = (i == num - 1);
+
+               dev_dbg(&adap->dev, "%s(): mode %d, %d bytes\n", __FUNCTION__,
+                       alg_data->mif.mode,
+                       alg_data->mif.len);
+
+               i2c_pnx_arm_timer(adap);
+
+               /* initialize the completion var */
+               init_completion(&alg_data->mif.complete);
+
+               /* Enable master interrupt */
+               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie |
+                               mcntrl_naie | mcntrl_drmie,
+                         I2C_REG_CTL(alg_data));
+
+               /* Put start-code and slave-address on the bus. */
+               rc = i2c_pnx_start(addr, adap);
+               if (rc < 0)
+                       break;
+
+               /* Wait for completion */
+               wait_for_completion(&alg_data->mif.complete);
+
+               if (!(rc = alg_data->mif.ret))
+                       completed++;
+               dev_dbg(&adap->dev, "%s(): Complete, return code = %d.\n",
+                       __FUNCTION__, rc);
+
+               /* Clear TDI and AFI bits in case they are set. */
+               if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) {
+                       dev_dbg(&adap->dev,
+                               "%s: TDI still set... clearing now.\n",
+                              adap->name);
+                       iowrite32(stat, I2C_REG_STS(alg_data));
+               }
+               if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) {
+                       dev_dbg(&adap->dev,
+                               "%s: AFI still set... clearing now.\n",
+                              adap->name);
+                       iowrite32(stat, I2C_REG_STS(alg_data));
+               }
+       }
+
+       bus_reset_if_active(adap);
+
+       /* Cleanup to be sure... */
+       alg_data->mif.buf = NULL;
+       alg_data->mif.len = 0;
+
+       dev_dbg(&adap->dev, "%s(): exiting, stat = %x\n",
+               __FUNCTION__, ioread32(I2C_REG_STS(alg_data)));
+
+       if (completed != num)
+               return ((rc < 0) ? rc : -EREMOTEIO);
+
+       return num;
+}
+
+static u32 i2c_pnx_func(struct i2c_adapter *adapter)
+{
+       return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm pnx_algorithm = {
+       .master_xfer = i2c_pnx_xfer,
+       .functionality = i2c_pnx_func,
+};
+
+static int i2c_pnx_controller_suspend(struct platform_device *pdev,
+                                     pm_message_t state)
+{
+       struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev);
+       return i2c_pnx->suspend(pdev, state);
+}
+
+static int i2c_pnx_controller_resume(struct platform_device *pdev)
+{
+       struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev);
+       return i2c_pnx->resume(pdev);
+}
+
+static int __devinit i2c_pnx_probe(struct platform_device *pdev)
+{
+       unsigned long tmp;
+       int ret = 0;
+       struct i2c_pnx_algo_data *alg_data;
+       int freq_mhz;
+       struct i2c_pnx_data *i2c_pnx = pdev->dev.platform_data;
+
+       if (!i2c_pnx || !i2c_pnx->adapter) {
+               dev_err(&pdev->dev, "%s: no platform data supplied\n",
+                      __FUNCTION__);
+               ret = -EINVAL;
+               goto out;
+       }
+
+       platform_set_drvdata(pdev, i2c_pnx);
+
+       if (i2c_pnx->calculate_input_freq)
+               freq_mhz = i2c_pnx->calculate_input_freq(pdev);
+       else {
+               freq_mhz = PNX_DEFAULT_FREQ;
+               dev_info(&pdev->dev, "Setting bus frequency to default value: "
+                      "%d MHz", freq_mhz);
+       }
+
+       i2c_pnx->adapter->algo = &pnx_algorithm;
+
+       alg_data = i2c_pnx->adapter->algo_data;
+       init_timer(&alg_data->mif.timer);
+       alg_data->mif.timer.function = i2c_pnx_timeout;
+       alg_data->mif.timer.data = (unsigned long)i2c_pnx->adapter;
+
+       /* Register I/O resource */
+       if (!request_region(alg_data->base, I2C_PNX_REGION_SIZE, pdev->name)) {
+               dev_err(&pdev->dev,
+                      "I/O region 0x%08x for I2C already in use.\n",
+                      alg_data->base);
+               ret = -ENODEV;
+               goto out_drvdata;
+       }
+
+       if (!(alg_data->ioaddr =
+                       (u32)ioremap(alg_data->base, I2C_PNX_REGION_SIZE))) {
+               dev_err(&pdev->dev, "Couldn't ioremap I2C I/O region\n");
+               ret = -ENOMEM;
+               goto out_release;
+       }
+
+       i2c_pnx->set_clock_run(pdev);
+
+       /*
+        * Clock Divisor High This value is the number of system clocks
+        * the serial clock (SCL) will be high.
+        * For example, if the system clock period is 50 ns and the maximum
+        * desired serial period is 10000 ns (100 kHz), then CLKHI would be
+        * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value
+        * programmed into CLKHI will vary from this slightly due to
+        * variations in the output pad's rise and fall times as well as
+        * the deglitching filter length.
+        */
+
+       tmp = ((freq_mhz * 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
+       iowrite32(tmp, I2C_REG_CKH(alg_data));
+       iowrite32(tmp, I2C_REG_CKL(alg_data));
+
+       iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
+       if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) {
+               ret = -ENODEV;
+               goto out_unmap;
+       }
+       init_completion(&alg_data->mif.complete);
+
+       ret = request_irq(alg_data->irq, i2c_pnx_interrupt,
+                       0, pdev->name, i2c_pnx->adapter);
+       if (ret)
+               goto out_clock;
+
+       /* Register this adapter with the I2C subsystem */
+       i2c_pnx->adapter->dev.parent = &pdev->dev;
+       ret = i2c_add_adapter(i2c_pnx->adapter);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "I2C: Failed to add bus\n");
+               goto out_irq;
+       }
+
+       dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n",
+              i2c_pnx->adapter->name, alg_data->base, alg_data->irq);
+
+       return 0;
+
+out_irq:
+       free_irq(alg_data->irq, alg_data);
+out_clock:
+       i2c_pnx->set_clock_stop(pdev);
+out_unmap:
+       iounmap((void *)alg_data->ioaddr);
+out_release:
+       release_region(alg_data->base, I2C_PNX_REGION_SIZE);
+out_drvdata:
+       platform_set_drvdata(pdev, NULL);
+out:
+       return ret;
+}
+
+static int __devexit i2c_pnx_remove(struct platform_device *pdev)
+{
+       struct i2c_pnx_data *i2c_pnx = platform_get_drvdata(pdev);
+       struct i2c_adapter *adap = i2c_pnx->adapter;
+       struct i2c_pnx_algo_data *alg_data = adap->algo_data;
+
+       free_irq(alg_data->irq, alg_data);
+       i2c_del_adapter(adap);
+       i2c_pnx->set_clock_stop(pdev);
+       iounmap((void *)alg_data->ioaddr);
+       release_region(alg_data->base, I2C_PNX_REGION_SIZE);
+       platform_set_drvdata(pdev, NULL);
+
+       return 0;
+}
+
+static struct platform_driver i2c_pnx_driver = {
+       .driver = {
+               .name = "pnx-i2c",
+               .owner = THIS_MODULE,
+       },
+       .probe = i2c_pnx_probe,
+       .remove = __devexit_p(i2c_pnx_remove),
+       .suspend = i2c_pnx_controller_suspend,
+       .resume = i2c_pnx_controller_resume,
+};
+
+static int __init i2c_adap_pnx_init(void)
+{
+       return platform_driver_register(&i2c_pnx_driver);
+}
+
+static void __exit i2c_adap_pnx_exit(void)
+{
+       platform_driver_unregister(&i2c_pnx_driver);
+}
+
+MODULE_AUTHOR("Vitaly Wool, Dennis Kovalev <source@mvista.com>");
+MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses");
+MODULE_LICENSE("GPL");
+
+/* We need to make sure I2C is initialized before USB */
+subsys_initcall(i2c_adap_pnx_init);
+module_exit(i2c_adap_pnx_exit);