Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / i2c / busses / i2c-rcar.c
diff --git a/kernel/drivers/i2c/busses/i2c-rcar.c b/kernel/drivers/i2c/busses/i2c-rcar.c
new file mode 100644 (file)
index 0000000..5a84bea
--- /dev/null
@@ -0,0 +1,738 @@
+/*
+ * Driver for the Renesas RCar I2C unit
+ *
+ * Copyright (C) 2014 Wolfram Sang <wsa@sang-engineering.com>
+ *
+ * Copyright (C) 2012-14 Renesas Solutions Corp.
+ * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
+ *
+ * This file is based on the drivers/i2c/busses/i2c-sh7760.c
+ * (c) 2005-2008 MSC Vertriebsges.m.b.H, Manuel Lauss <mlau@msc-ge.com>
+ *
+ * This file used out-of-tree driver i2c-rcar.c
+ * Copyright (C) 2011-2012 Renesas Electronics Corporation
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/i2c/i2c-rcar.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+/* register offsets */
+#define ICSCR  0x00    /* slave ctrl */
+#define ICMCR  0x04    /* master ctrl */
+#define ICSSR  0x08    /* slave status */
+#define ICMSR  0x0C    /* master status */
+#define ICSIER 0x10    /* slave irq enable */
+#define ICMIER 0x14    /* master irq enable */
+#define ICCCR  0x18    /* clock dividers */
+#define ICSAR  0x1C    /* slave address */
+#define ICMAR  0x20    /* master address */
+#define ICRXTX 0x24    /* data port */
+
+/* ICSCR */
+#define SDBS   (1 << 3)        /* slave data buffer select */
+#define SIE    (1 << 2)        /* slave interface enable */
+#define GCAE   (1 << 1)        /* general call address enable */
+#define FNA    (1 << 0)        /* forced non acknowledgment */
+
+/* ICMCR */
+#define MDBS   (1 << 7)        /* non-fifo mode switch */
+#define FSCL   (1 << 6)        /* override SCL pin */
+#define FSDA   (1 << 5)        /* override SDA pin */
+#define OBPC   (1 << 4)        /* override pins */
+#define MIE    (1 << 3)        /* master if enable */
+#define TSBE   (1 << 2)
+#define FSB    (1 << 1)        /* force stop bit */
+#define ESG    (1 << 0)        /* en startbit gen */
+
+/* ICSSR (also for ICSIER) */
+#define GCAR   (1 << 6)        /* general call received */
+#define STM    (1 << 5)        /* slave transmit mode */
+#define SSR    (1 << 4)        /* stop received */
+#define SDE    (1 << 3)        /* slave data empty */
+#define SDT    (1 << 2)        /* slave data transmitted */
+#define SDR    (1 << 1)        /* slave data received */
+#define SAR    (1 << 0)        /* slave addr received */
+
+/* ICMSR (also for ICMIE) */
+#define MNR    (1 << 6)        /* nack received */
+#define MAL    (1 << 5)        /* arbitration lost */
+#define MST    (1 << 4)        /* sent a stop */
+#define MDE    (1 << 3)
+#define MDT    (1 << 2)
+#define MDR    (1 << 1)
+#define MAT    (1 << 0)        /* slave addr xfer done */
+
+
+#define RCAR_BUS_PHASE_START   (MDBS | MIE | ESG)
+#define RCAR_BUS_PHASE_DATA    (MDBS | MIE)
+#define RCAR_BUS_PHASE_STOP    (MDBS | MIE | FSB)
+
+#define RCAR_IRQ_SEND  (MNR | MAL | MST | MAT | MDE)
+#define RCAR_IRQ_RECV  (MNR | MAL | MST | MAT | MDR)
+#define RCAR_IRQ_STOP  (MST)
+
+#define RCAR_IRQ_ACK_SEND      (~(MAT | MDE) & 0xFF)
+#define RCAR_IRQ_ACK_RECV      (~(MAT | MDR) & 0xFF)
+
+#define ID_LAST_MSG    (1 << 0)
+#define ID_IOERROR     (1 << 1)
+#define ID_DONE                (1 << 2)
+#define ID_ARBLOST     (1 << 3)
+#define ID_NACK                (1 << 4)
+
+enum rcar_i2c_type {
+       I2C_RCAR_GEN1,
+       I2C_RCAR_GEN2,
+};
+
+struct rcar_i2c_priv {
+       void __iomem *io;
+       struct i2c_adapter adap;
+       struct i2c_msg  *msg;
+       struct clk *clk;
+
+       spinlock_t lock;
+       wait_queue_head_t wait;
+
+       int pos;
+       u32 icccr;
+       u32 flags;
+       enum rcar_i2c_type devtype;
+       struct i2c_client *slave;
+};
+
+#define rcar_i2c_priv_to_dev(p)                ((p)->adap.dev.parent)
+#define rcar_i2c_is_recv(p)            ((p)->msg->flags & I2C_M_RD)
+
+#define rcar_i2c_flags_set(p, f)       ((p)->flags |= (f))
+#define rcar_i2c_flags_has(p, f)       ((p)->flags & (f))
+
+#define LOOP_TIMEOUT   1024
+
+
+static void rcar_i2c_write(struct rcar_i2c_priv *priv, int reg, u32 val)
+{
+       writel(val, priv->io + reg);
+}
+
+static u32 rcar_i2c_read(struct rcar_i2c_priv *priv, int reg)
+{
+       return readl(priv->io + reg);
+}
+
+static void rcar_i2c_init(struct rcar_i2c_priv *priv)
+{
+       /* reset master mode */
+       rcar_i2c_write(priv, ICMIER, 0);
+       rcar_i2c_write(priv, ICMCR, 0);
+       rcar_i2c_write(priv, ICMSR, 0);
+       rcar_i2c_write(priv, ICMAR, 0);
+}
+
+static int rcar_i2c_bus_barrier(struct rcar_i2c_priv *priv)
+{
+       int i;
+
+       for (i = 0; i < LOOP_TIMEOUT; i++) {
+               /* make sure that bus is not busy */
+               if (!(rcar_i2c_read(priv, ICMCR) & FSDA))
+                       return 0;
+               udelay(1);
+       }
+
+       return -EBUSY;
+}
+
+static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
+                                   u32 bus_speed,
+                                   struct device *dev)
+{
+       u32 scgd, cdf;
+       u32 round, ick;
+       u32 scl;
+       u32 cdf_width;
+       unsigned long rate;
+
+       switch (priv->devtype) {
+       case I2C_RCAR_GEN1:
+               cdf_width = 2;
+               break;
+       case I2C_RCAR_GEN2:
+               cdf_width = 3;
+               break;
+       default:
+               dev_err(dev, "device type error\n");
+               return -EIO;
+       }
+
+       /*
+        * calculate SCL clock
+        * see
+        *      ICCCR
+        *
+        * ick  = clkp / (1 + CDF)
+        * SCL  = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
+        *
+        * ick  : I2C internal clock < 20 MHz
+        * ticf : I2C SCL falling time  =  35 ns here
+        * tr   : I2C SCL rising  time  = 200 ns here
+        * intd : LSI internal delay    =  50 ns here
+        * clkp : peripheral_clk
+        * F[]  : integer up-valuation
+        */
+       rate = clk_get_rate(priv->clk);
+       cdf = rate / 20000000;
+       if (cdf >= 1U << cdf_width) {
+               dev_err(dev, "Input clock %lu too high\n", rate);
+               return -EIO;
+       }
+       ick = rate / (cdf + 1);
+
+       /*
+        * it is impossible to calculate large scale
+        * number on u32. separate it
+        *
+        * F[(ticf + tr + intd) * ick]
+        *  = F[(35 + 200 + 50)ns * ick]
+        *  = F[285 * ick / 1000000000]
+        *  = F[(ick / 1000000) * 285 / 1000]
+        */
+       round = (ick + 500000) / 1000000 * 285;
+       round = (round + 500) / 1000;
+
+       /*
+        * SCL  = ick / (20 + SCGD * 8 + F[(ticf + tr + intd) * ick])
+        *
+        * Calculation result (= SCL) should be less than
+        * bus_speed for hardware safety
+        *
+        * We could use something along the lines of
+        *      div = ick / (bus_speed + 1) + 1;
+        *      scgd = (div - 20 - round + 7) / 8;
+        *      scl = ick / (20 + (scgd * 8) + round);
+        * (not fully verified) but that would get pretty involved
+        */
+       for (scgd = 0; scgd < 0x40; scgd++) {
+               scl = ick / (20 + (scgd * 8) + round);
+               if (scl <= bus_speed)
+                       goto scgd_find;
+       }
+       dev_err(dev, "it is impossible to calculate best SCL\n");
+       return -EIO;
+
+scgd_find:
+       dev_dbg(dev, "clk %d/%d(%lu), round %u, CDF:0x%x, SCGD: 0x%x\n",
+               scl, bus_speed, clk_get_rate(priv->clk), round, cdf, scgd);
+
+       /*
+        * keep icccr value
+        */
+       priv->icccr = scgd << cdf_width | cdf;
+
+       return 0;
+}
+
+static void rcar_i2c_prepare_msg(struct rcar_i2c_priv *priv)
+{
+       int read = !!rcar_i2c_is_recv(priv);
+
+       rcar_i2c_write(priv, ICMAR, (priv->msg->addr << 1) | read);
+       rcar_i2c_write(priv, ICMSR, 0);
+       rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_START);
+       rcar_i2c_write(priv, ICMIER, read ? RCAR_IRQ_RECV : RCAR_IRQ_SEND);
+}
+
+/*
+ *             interrupt functions
+ */
+static int rcar_i2c_irq_send(struct rcar_i2c_priv *priv, u32 msr)
+{
+       struct i2c_msg *msg = priv->msg;
+
+       /*
+        * FIXME
+        * sometimes, unknown interrupt happened.
+        * Do nothing
+        */
+       if (!(msr & MDE))
+               return 0;
+
+       /*
+        * If address transfer phase finished,
+        * goto data phase.
+        */
+       if (msr & MAT)
+               rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
+
+       if (priv->pos < msg->len) {
+               /*
+                * Prepare next data to ICRXTX register.
+                * This data will go to _SHIFT_ register.
+                *
+                *    *
+                * [ICRXTX] -> [SHIFT] -> [I2C bus]
+                */
+               rcar_i2c_write(priv, ICRXTX, msg->buf[priv->pos]);
+               priv->pos++;
+
+       } else {
+               /*
+                * The last data was pushed to ICRXTX on _PREV_ empty irq.
+                * It is on _SHIFT_ register, and will sent to I2C bus.
+                *
+                *                *
+                * [ICRXTX] -> [SHIFT] -> [I2C bus]
+                */
+
+               if (priv->flags & ID_LAST_MSG)
+                       /*
+                        * If current msg is the _LAST_ msg,
+                        * prepare stop condition here.
+                        * ID_DONE will be set on STOP irq.
+                        */
+                       rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
+               else
+                       /*
+                        * If current msg is _NOT_ last msg,
+                        * it doesn't call stop phase.
+                        * thus, there is no STOP irq.
+                        * return ID_DONE here.
+                        */
+                       return ID_DONE;
+       }
+
+       rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_SEND);
+
+       return 0;
+}
+
+static int rcar_i2c_irq_recv(struct rcar_i2c_priv *priv, u32 msr)
+{
+       struct i2c_msg *msg = priv->msg;
+
+       /*
+        * FIXME
+        * sometimes, unknown interrupt happened.
+        * Do nothing
+        */
+       if (!(msr & MDR))
+               return 0;
+
+       if (msr & MAT) {
+               /*
+                * Address transfer phase finished,
+                * but, there is no data at this point.
+                * Do nothing.
+                */
+       } else if (priv->pos < msg->len) {
+               /*
+                * get received data
+                */
+               msg->buf[priv->pos] = rcar_i2c_read(priv, ICRXTX);
+               priv->pos++;
+       }
+
+       /*
+        * If next received data is the _LAST_,
+        * go to STOP phase,
+        * otherwise, go to DATA phase.
+        */
+       if (priv->pos + 1 >= msg->len)
+               rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
+       else
+               rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_DATA);
+
+       rcar_i2c_write(priv, ICMSR, RCAR_IRQ_ACK_RECV);
+
+       return 0;
+}
+
+static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv)
+{
+       u32 ssr_raw, ssr_filtered;
+       u8 value;
+
+       ssr_raw = rcar_i2c_read(priv, ICSSR) & 0xff;
+       ssr_filtered = ssr_raw & rcar_i2c_read(priv, ICSIER);
+
+       if (!ssr_filtered)
+               return false;
+
+       /* address detected */
+       if (ssr_filtered & SAR) {
+               /* read or write request */
+               if (ssr_raw & STM) {
+                       i2c_slave_event(priv->slave, I2C_SLAVE_READ_REQUESTED, &value);
+                       rcar_i2c_write(priv, ICRXTX, value);
+                       rcar_i2c_write(priv, ICSIER, SDE | SSR | SAR);
+               } else {
+                       i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_REQUESTED, &value);
+                       rcar_i2c_read(priv, ICRXTX);    /* dummy read */
+                       rcar_i2c_write(priv, ICSIER, SDR | SSR | SAR);
+               }
+
+               rcar_i2c_write(priv, ICSSR, ~SAR & 0xff);
+       }
+
+       /* master sent stop */
+       if (ssr_filtered & SSR) {
+               i2c_slave_event(priv->slave, I2C_SLAVE_STOP, &value);
+               rcar_i2c_write(priv, ICSIER, SAR | SSR);
+               rcar_i2c_write(priv, ICSSR, ~SSR & 0xff);
+       }
+
+       /* master wants to write to us */
+       if (ssr_filtered & SDR) {
+               int ret;
+
+               value = rcar_i2c_read(priv, ICRXTX);
+               ret = i2c_slave_event(priv->slave, I2C_SLAVE_WRITE_RECEIVED, &value);
+               /* Send NACK in case of error */
+               rcar_i2c_write(priv, ICSCR, SIE | SDBS | (ret < 0 ? FNA : 0));
+               rcar_i2c_write(priv, ICSSR, ~SDR & 0xff);
+       }
+
+       /* master wants to read from us */
+       if (ssr_filtered & SDE) {
+               i2c_slave_event(priv->slave, I2C_SLAVE_READ_PROCESSED, &value);
+               rcar_i2c_write(priv, ICRXTX, value);
+               rcar_i2c_write(priv, ICSSR, ~SDE & 0xff);
+       }
+
+       return true;
+}
+
+static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
+{
+       struct rcar_i2c_priv *priv = ptr;
+       irqreturn_t result = IRQ_HANDLED;
+       u32 msr;
+
+       /*-------------- spin lock -----------------*/
+       spin_lock(&priv->lock);
+
+       if (rcar_i2c_slave_irq(priv))
+               goto exit;
+
+       msr = rcar_i2c_read(priv, ICMSR);
+
+       /* Only handle interrupts that are currently enabled */
+       msr &= rcar_i2c_read(priv, ICMIER);
+       if (!msr) {
+               result = IRQ_NONE;
+               goto exit;
+       }
+
+       /* Arbitration lost */
+       if (msr & MAL) {
+               rcar_i2c_flags_set(priv, (ID_DONE | ID_ARBLOST));
+               goto out;
+       }
+
+       /* Nack */
+       if (msr & MNR) {
+               /* go to stop phase */
+               rcar_i2c_write(priv, ICMCR, RCAR_BUS_PHASE_STOP);
+               rcar_i2c_write(priv, ICMIER, RCAR_IRQ_STOP);
+               rcar_i2c_flags_set(priv, ID_NACK);
+               goto out;
+       }
+
+       /* Stop */
+       if (msr & MST) {
+               rcar_i2c_flags_set(priv, ID_DONE);
+               goto out;
+       }
+
+       if (rcar_i2c_is_recv(priv))
+               rcar_i2c_flags_set(priv, rcar_i2c_irq_recv(priv, msr));
+       else
+               rcar_i2c_flags_set(priv, rcar_i2c_irq_send(priv, msr));
+
+out:
+       if (rcar_i2c_flags_has(priv, ID_DONE)) {
+               rcar_i2c_write(priv, ICMIER, 0);
+               rcar_i2c_write(priv, ICMSR, 0);
+               wake_up(&priv->wait);
+       }
+
+exit:
+       spin_unlock(&priv->lock);
+       /*-------------- spin unlock -----------------*/
+
+       return result;
+}
+
+static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
+                               struct i2c_msg *msgs,
+                               int num)
+{
+       struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
+       struct device *dev = rcar_i2c_priv_to_dev(priv);
+       unsigned long flags;
+       int i, ret, timeout;
+
+       pm_runtime_get_sync(dev);
+
+       /*-------------- spin lock -----------------*/
+       spin_lock_irqsave(&priv->lock, flags);
+
+       rcar_i2c_init(priv);
+       /* start clock */
+       rcar_i2c_write(priv, ICCCR, priv->icccr);
+
+       spin_unlock_irqrestore(&priv->lock, flags);
+       /*-------------- spin unlock -----------------*/
+
+       ret = rcar_i2c_bus_barrier(priv);
+       if (ret < 0)
+               goto out;
+
+       for (i = 0; i < num; i++) {
+               /* This HW can't send STOP after address phase */
+               if (msgs[i].len == 0) {
+                       ret = -EOPNOTSUPP;
+                       break;
+               }
+
+               /*-------------- spin lock -----------------*/
+               spin_lock_irqsave(&priv->lock, flags);
+
+               /* init each data */
+               priv->msg       = &msgs[i];
+               priv->pos       = 0;
+               priv->flags     = 0;
+               if (i == num - 1)
+                       rcar_i2c_flags_set(priv, ID_LAST_MSG);
+
+               rcar_i2c_prepare_msg(priv);
+
+               spin_unlock_irqrestore(&priv->lock, flags);
+               /*-------------- spin unlock -----------------*/
+
+               timeout = wait_event_timeout(priv->wait,
+                                            rcar_i2c_flags_has(priv, ID_DONE),
+                                            5 * HZ);
+               if (!timeout) {
+                       ret = -ETIMEDOUT;
+                       break;
+               }
+
+               if (rcar_i2c_flags_has(priv, ID_NACK)) {
+                       ret = -ENXIO;
+                       break;
+               }
+
+               if (rcar_i2c_flags_has(priv, ID_ARBLOST)) {
+                       ret = -EAGAIN;
+                       break;
+               }
+
+               if (rcar_i2c_flags_has(priv, ID_IOERROR)) {
+                       ret = -EIO;
+                       break;
+               }
+
+               ret = i + 1; /* The number of transfer */
+       }
+out:
+       pm_runtime_put(dev);
+
+       if (ret < 0 && ret != -ENXIO)
+               dev_err(dev, "error %d : %x\n", ret, priv->flags);
+
+       return ret;
+}
+
+static int rcar_reg_slave(struct i2c_client *slave)
+{
+       struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter);
+
+       if (priv->slave)
+               return -EBUSY;
+
+       if (slave->flags & I2C_CLIENT_TEN)
+               return -EAFNOSUPPORT;
+
+       pm_runtime_forbid(rcar_i2c_priv_to_dev(priv));
+
+       priv->slave = slave;
+       rcar_i2c_write(priv, ICSAR, slave->addr);
+       rcar_i2c_write(priv, ICSSR, 0);
+       rcar_i2c_write(priv, ICSIER, SAR | SSR);
+       rcar_i2c_write(priv, ICSCR, SIE | SDBS);
+
+       return 0;
+}
+
+static int rcar_unreg_slave(struct i2c_client *slave)
+{
+       struct rcar_i2c_priv *priv = i2c_get_adapdata(slave->adapter);
+
+       WARN_ON(!priv->slave);
+
+       rcar_i2c_write(priv, ICSIER, 0);
+       rcar_i2c_write(priv, ICSCR, 0);
+
+       priv->slave = NULL;
+
+       pm_runtime_allow(rcar_i2c_priv_to_dev(priv));
+
+       return 0;
+}
+
+static u32 rcar_i2c_func(struct i2c_adapter *adap)
+{
+       /* This HW can't do SMBUS_QUICK and NOSTART */
+       return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+static const struct i2c_algorithm rcar_i2c_algo = {
+       .master_xfer    = rcar_i2c_master_xfer,
+       .functionality  = rcar_i2c_func,
+       .reg_slave      = rcar_reg_slave,
+       .unreg_slave    = rcar_unreg_slave,
+};
+
+static const struct of_device_id rcar_i2c_dt_ids[] = {
+       { .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 },
+       { .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 },
+       { .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 },
+       { .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 },
+       { .compatible = "renesas,i2c-r8a7791", .data = (void *)I2C_RCAR_GEN2 },
+       { .compatible = "renesas,i2c-r8a7792", .data = (void *)I2C_RCAR_GEN2 },
+       { .compatible = "renesas,i2c-r8a7793", .data = (void *)I2C_RCAR_GEN2 },
+       { .compatible = "renesas,i2c-r8a7794", .data = (void *)I2C_RCAR_GEN2 },
+       {},
+};
+MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
+
+static int rcar_i2c_probe(struct platform_device *pdev)
+{
+       struct i2c_rcar_platform_data *pdata = dev_get_platdata(&pdev->dev);
+       struct rcar_i2c_priv *priv;
+       struct i2c_adapter *adap;
+       struct resource *res;
+       struct device *dev = &pdev->dev;
+       u32 bus_speed;
+       int irq, ret;
+
+       priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       priv->clk = devm_clk_get(dev, NULL);
+       if (IS_ERR(priv->clk)) {
+               dev_err(dev, "cannot get clock\n");
+               return PTR_ERR(priv->clk);
+       }
+
+       bus_speed = 100000; /* default 100 kHz */
+       ret = of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
+       if (ret < 0 && pdata && pdata->bus_speed)
+               bus_speed = pdata->bus_speed;
+
+       if (pdev->dev.of_node)
+               priv->devtype = (long)of_match_device(rcar_i2c_dt_ids,
+                                                     dev)->data;
+       else
+               priv->devtype = platform_get_device_id(pdev)->driver_data;
+
+       ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
+       if (ret < 0)
+               return ret;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       priv->io = devm_ioremap_resource(dev, res);
+       if (IS_ERR(priv->io))
+               return PTR_ERR(priv->io);
+
+       irq = platform_get_irq(pdev, 0);
+       init_waitqueue_head(&priv->wait);
+       spin_lock_init(&priv->lock);
+
+       adap = &priv->adap;
+       adap->nr = pdev->id;
+       adap->algo = &rcar_i2c_algo;
+       adap->class = I2C_CLASS_DEPRECATED;
+       adap->retries = 3;
+       adap->dev.parent = dev;
+       adap->dev.of_node = dev->of_node;
+       i2c_set_adapdata(adap, priv);
+       strlcpy(adap->name, pdev->name, sizeof(adap->name));
+
+       ret = devm_request_irq(dev, irq, rcar_i2c_irq, 0,
+                              dev_name(dev), priv);
+       if (ret < 0) {
+               dev_err(dev, "cannot get irq %d\n", irq);
+               return ret;
+       }
+
+       ret = i2c_add_numbered_adapter(adap);
+       if (ret < 0) {
+               dev_err(dev, "reg adap failed: %d\n", ret);
+               return ret;
+       }
+
+       pm_runtime_enable(dev);
+       platform_set_drvdata(pdev, priv);
+
+       dev_info(dev, "probed\n");
+
+       return 0;
+}
+
+static int rcar_i2c_remove(struct platform_device *pdev)
+{
+       struct rcar_i2c_priv *priv = platform_get_drvdata(pdev);
+       struct device *dev = &pdev->dev;
+
+       i2c_del_adapter(&priv->adap);
+       pm_runtime_disable(dev);
+
+       return 0;
+}
+
+static struct platform_device_id rcar_i2c_id_table[] = {
+       { "i2c-rcar",           I2C_RCAR_GEN1 },
+       { "i2c-rcar_gen1",      I2C_RCAR_GEN1 },
+       { "i2c-rcar_gen2",      I2C_RCAR_GEN2 },
+       {},
+};
+MODULE_DEVICE_TABLE(platform, rcar_i2c_id_table);
+
+static struct platform_driver rcar_i2c_driver = {
+       .driver = {
+               .name   = "i2c-rcar",
+               .of_match_table = rcar_i2c_dt_ids,
+       },
+       .probe          = rcar_i2c_probe,
+       .remove         = rcar_i2c_remove,
+       .id_table       = rcar_i2c_id_table,
+};
+
+module_platform_driver(rcar_i2c_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Renesas R-Car I2C bus driver");
+MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");