Merge tag 'imx-defconfig-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/shawng...
[cascardo/linux.git] / drivers / i2c / busses / i2c-octeon.c
index 46fb6c4..30ae351 100644 (file)
@@ -11,6 +11,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/atomic.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 /* Register offsets */
 #define SW_TWSI                        0x00
 #define TWSI_INT               0x10
+#define SW_TWSI_EXT            0x18
 
 /* Controller command patterns */
 #define SW_TWSI_V              BIT_ULL(63)     /* Valid bit */
+#define SW_TWSI_EIA            BIT_ULL(61)     /* Extended internal address */
 #define SW_TWSI_R              BIT_ULL(56)     /* Result or read bit */
+#define SW_TWSI_SOVR           BIT_ULL(55)     /* Size override */
+#define SW_TWSI_SIZE_SHIFT     52
+#define SW_TWSI_ADDR_SHIFT     40
+#define SW_TWSI_IA_SHIFT       32              /* Internal address */
 
 /* Controller opcode word (bits 60:57) */
 #define SW_TWSI_OP_SHIFT       57
+#define SW_TWSI_OP_7           (0ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_7_IA                (1ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_10          (2ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_10_IA       (3ULL << SW_TWSI_OP_SHIFT)
 #define SW_TWSI_OP_TWSI_CLK    (4ULL << SW_TWSI_OP_SHIFT)
 #define SW_TWSI_OP_EOP         (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */
 
 #define SW_TWSI_EOP_TWSI_RST   (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT)
 
 /* Controller command and status bits */
-#define TWSI_CTL_CE            0x80
+#define TWSI_CTL_CE            0x80    /* High level controller enable */
 #define TWSI_CTL_ENAB          0x40    /* Bus enable */
 #define TWSI_CTL_STA           0x20    /* Master-mode start, HW clears when done */
 #define TWSI_CTL_STP           0x10    /* Master-mode stop, HW clears when done */
 #define TWSI_CTL_IFLG          0x08    /* HW event, SW writes 0 to ACK */
 #define TWSI_CTL_AAK           0x04    /* Assert ACK */
 
-/* Some status values */
+/* Status values */
+#define STAT_ERROR             0x00
 #define STAT_START             0x08
-#define STAT_RSTART            0x10
+#define STAT_REP_START         0x10
 #define STAT_TXADDR_ACK                0x18
+#define STAT_TXADDR_NAK                0x20
 #define STAT_TXDATA_ACK                0x28
+#define STAT_TXDATA_NAK                0x30
+#define STAT_LOST_ARB_38       0x38
 #define STAT_RXADDR_ACK                0x40
+#define STAT_RXADDR_NAK                0x48
 #define STAT_RXDATA_ACK                0x50
+#define STAT_RXDATA_NAK                0x58
+#define STAT_SLAVE_60          0x60
+#define STAT_LOST_ARB_68       0x68
+#define STAT_SLAVE_70          0x70
+#define STAT_LOST_ARB_78       0x78
+#define STAT_SLAVE_80          0x80
+#define STAT_SLAVE_88          0x88
+#define STAT_GENDATA_ACK       0x90
+#define STAT_GENDATA_NAK       0x98
+#define STAT_SLAVE_A0          0xA0
+#define STAT_SLAVE_A8          0xA8
+#define STAT_LOST_ARB_B0       0xB0
+#define STAT_SLAVE_LOST                0xB8
+#define STAT_SLAVE_NAK         0xC0
+#define STAT_SLAVE_ACK         0xC8
+#define STAT_AD2W_ACK          0xD0
+#define STAT_AD2W_NAK          0xD8
 #define STAT_IDLE              0xF8
 
 /* TWSI_INT values */
+#define TWSI_INT_ST_INT                BIT_ULL(0)
+#define TWSI_INT_TS_INT                BIT_ULL(1)
+#define TWSI_INT_CORE_INT      BIT_ULL(2)
+#define TWSI_INT_ST_EN         BIT_ULL(4)
+#define TWSI_INT_TS_EN         BIT_ULL(5)
 #define TWSI_INT_CORE_EN       BIT_ULL(6)
 #define TWSI_INT_SDA_OVR       BIT_ULL(8)
 #define TWSI_INT_SCL_OVR       BIT_ULL(9)
+#define TWSI_INT_SDA           BIT_ULL(10)
+#define TWSI_INT_SCL           BIT_ULL(11)
+
+#define I2C_OCTEON_EVENT_WAIT 80 /* microseconds */
 
 struct octeon_i2c {
        wait_queue_head_t queue;
        struct i2c_adapter adap;
        int irq;
+       int hlc_irq;            /* For cn7890 only */
        u32 twsi_freq;
        int sys_freq;
        void __iomem *twsi_base;
        struct device *dev;
+       bool hlc_enabled;
+       bool broken_irq_mode;
+       bool broken_irq_check;
+       void (*int_enable)(struct octeon_i2c *);
+       void (*int_disable)(struct octeon_i2c *);
+       void (*hlc_int_enable)(struct octeon_i2c *);
+       void (*hlc_int_disable)(struct octeon_i2c *);
+       atomic_t int_enable_cnt;
+       atomic_t hlc_int_enable_cnt;
 };
 
+static void octeon_i2c_writeq_flush(u64 val, void __iomem *addr)
+{
+       __raw_writeq(val, addr);
+       __raw_readq(addr);      /* wait for write to land */
+}
+
 /**
- * octeon_i2c_write_sw - write an I2C core register
+ * octeon_i2c_reg_write - write an I2C core register
  * @i2c: The struct octeon_i2c
  * @eop_reg: Register selector
  * @data: Value to be written
  *
  * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
  */
-static void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
+static void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
 {
        u64 tmp;
 
@@ -97,8 +155,13 @@ static void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
        } while ((tmp & SW_TWSI_V) != 0);
 }
 
+#define octeon_i2c_ctl_write(i2c, val)                                 \
+       octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CTL, val)
+#define octeon_i2c_data_write(i2c, val)                                        \
+       octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_DATA, val)
+
 /**
- * octeon_i2c_read_sw - read lower bits of an I2C core register
+ * octeon_i2c_reg_read - read lower bits of an I2C core register
  * @i2c: The struct octeon_i2c
  * @eop_reg: Register selector
  *
@@ -106,7 +169,7 @@ static void octeon_i2c_write_sw(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
  *
  * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
  */
-static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
+static u8 octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg)
 {
        u64 tmp;
 
@@ -118,6 +181,24 @@ static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
        return tmp & 0xFF;
 }
 
+#define octeon_i2c_ctl_read(i2c)                                       \
+       octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL)
+#define octeon_i2c_data_read(i2c)                                      \
+       octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA)
+#define octeon_i2c_stat_read(i2c)                                      \
+       octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT)
+
+/**
+ * octeon_i2c_read_int - read the TWSI_INT register
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns the value of the register.
+ */
+static u64 octeon_i2c_read_int(struct octeon_i2c *i2c)
+{
+       return __raw_readq(i2c->twsi_base + TWSI_INT);
+}
+
 /**
  * octeon_i2c_write_int - write the TWSI_INT register
  * @i2c: The struct octeon_i2c
@@ -125,8 +206,7 @@ static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
  */
 static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
 {
-       __raw_writeq(data, i2c->twsi_base + TWSI_INT);
-       __raw_readq(i2c->twsi_base + TWSI_INT);
+       octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT);
 }
 
 /**
@@ -149,30 +229,96 @@ static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
 }
 
 /**
- * octeon_i2c_unblock - unblock the bus
+ * octeon_i2c_int_enable78 - enable the CORE interrupt
+ * @i2c: The struct octeon_i2c
+ *
+ * The interrupt will be asserted when there is non-STAT_IDLE state in the
+ * SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_int_enable78(struct octeon_i2c *i2c)
+{
+       atomic_inc_return(&i2c->int_enable_cnt);
+       enable_irq(i2c->irq);
+}
+
+static void __octeon_i2c_irq_disable(atomic_t *cnt, int irq)
+{
+       int count;
+
+       /*
+        * The interrupt can be disabled in two places, but we only
+        * want to make the disable_irq_nosync() call once, so keep
+        * track with the atomic variable.
+        */
+       count = atomic_dec_if_positive(cnt);
+       if (count >= 0)
+               disable_irq_nosync(irq);
+}
+
+/* disable the CORE interrupt */
+static void octeon_i2c_int_disable78(struct octeon_i2c *i2c)
+{
+       __octeon_i2c_irq_disable(&i2c->int_enable_cnt, i2c->irq);
+}
+
+/**
+ * octeon_i2c_hlc_int_enable78 - enable the ST interrupt
  * @i2c: The struct octeon_i2c
  *
- * If there was a reset while a device was driving 0 to bus, bus is blocked.
- * We toggle it free manually by some clock cycles and send a stop.
+ * The interrupt will be asserted when there is non-STAT_IDLE state in
+ * the SW_TWSI_EOP_TWSI_STAT register.
+ */
+static void octeon_i2c_hlc_int_enable78(struct octeon_i2c *i2c)
+{
+       atomic_inc_return(&i2c->hlc_int_enable_cnt);
+       enable_irq(i2c->hlc_irq);
+}
+
+/* disable the ST interrupt */
+static void octeon_i2c_hlc_int_disable78(struct octeon_i2c *i2c)
+{
+       __octeon_i2c_irq_disable(&i2c->hlc_int_enable_cnt, i2c->hlc_irq);
+}
+
+/*
+ * Cleanup low-level state & enable high-level controller.
  */
-static void octeon_i2c_unblock(struct octeon_i2c *i2c)
+static void octeon_i2c_hlc_enable(struct octeon_i2c *i2c)
 {
-       int i;
+       int try = 0;
+       u64 val;
+
+       if (i2c->hlc_enabled)
+               return;
+       i2c->hlc_enabled = true;
+
+       while (1) {
+               val = octeon_i2c_ctl_read(i2c);
+               if (!(val & (TWSI_CTL_STA | TWSI_CTL_STP)))
+                       break;
 
-       dev_dbg(i2c->dev, "%s\n", __func__);
+               /* clear IFLG event */
+               if (val & TWSI_CTL_IFLG)
+                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+               if (try++ > 100) {
+                       pr_err("%s: giving up\n", __func__);
+                       break;
+               }
 
-       for (i = 0; i < 9; i++) {
-               octeon_i2c_write_int(i2c, 0);
-               udelay(5);
-               octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
-               udelay(5);
+               /* spin until any start/stop has finished */
+               udelay(10);
        }
-       /* hand-crank a STOP */
-       octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR | TWSI_INT_SCL_OVR);
-       udelay(5);
-       octeon_i2c_write_int(i2c, TWSI_INT_SDA_OVR);
-       udelay(5);
-       octeon_i2c_write_int(i2c, 0);
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_CE | TWSI_CTL_AAK | TWSI_CTL_ENAB);
+}
+
+static void octeon_i2c_hlc_disable(struct octeon_i2c *i2c)
+{
+       if (!i2c->hlc_enabled)
+               return;
+
+       i2c->hlc_enabled = false;
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
 }
 
 /* interrupt service routine */
@@ -180,16 +326,44 @@ static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
 {
        struct octeon_i2c *i2c = dev_id;
 
-       octeon_i2c_int_disable(i2c);
+       i2c->int_disable(i2c);
+       wake_up(&i2c->queue);
+
+       return IRQ_HANDLED;
+}
+
+/* HLC interrupt service routine */
+static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
+{
+       struct octeon_i2c *i2c = dev_id;
+
+       i2c->hlc_int_disable(i2c);
        wake_up(&i2c->queue);
 
        return IRQ_HANDLED;
 }
 
+static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c)
+{
+       return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
+}
 
-static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
+static bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
 {
-       return (octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_CTL) & TWSI_CTL_IFLG) != 0;
+       if (octeon_i2c_test_iflg(i2c))
+               return true;
+
+       if (*first) {
+               *first = false;
+               return false;
+       }
+
+       /*
+        * IRQ has signaled an event but IFLG hasn't changed.
+        * Sleep and retry once.
+        */
+       usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
+       return octeon_i2c_test_iflg(i2c);
 }
 
 /**
@@ -201,64 +375,493 @@ static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
 static int octeon_i2c_wait(struct octeon_i2c *i2c)
 {
        long time_left;
+       bool first = 1;
 
-       octeon_i2c_int_enable(i2c);
-       time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c),
+       /*
+        * Some chip revisions don't assert the irq in the interrupt
+        * controller. So we must poll for the IFLG change.
+        */
+       if (i2c->broken_irq_mode) {
+               u64 end = get_jiffies_64() + i2c->adap.timeout;
+
+               while (!octeon_i2c_test_iflg(i2c) &&
+                      time_before64(get_jiffies_64(), end))
+                       usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
+
+               return octeon_i2c_test_iflg(i2c) ? 0 : -ETIMEDOUT;
+       }
+
+       i2c->int_enable(i2c);
+       time_left = wait_event_timeout(i2c->queue, octeon_i2c_test_ready(i2c, &first),
                                       i2c->adap.timeout);
-       octeon_i2c_int_disable(i2c);
-       if (!time_left) {
-               dev_dbg(i2c->dev, "%s: timeout\n", __func__);
-               return -ETIMEDOUT;
+       i2c->int_disable(i2c);
+
+       if (i2c->broken_irq_check && !time_left &&
+           octeon_i2c_test_iflg(i2c)) {
+               dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
+               i2c->broken_irq_mode = true;
+               return 0;
        }
 
+       if (!time_left)
+               return -ETIMEDOUT;
+
        return 0;
 }
 
+static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
+{
+       u8 stat = octeon_i2c_stat_read(i2c);
+
+       switch (stat) {
+       /* Everything is fine */
+       case STAT_IDLE:
+       case STAT_AD2W_ACK:
+       case STAT_RXADDR_ACK:
+       case STAT_TXADDR_ACK:
+       case STAT_TXDATA_ACK:
+               return 0;
+
+       /* ACK allowed on pre-terminal bytes only */
+       case STAT_RXDATA_ACK:
+               if (!final_read)
+                       return 0;
+               return -EIO;
+
+       /* NAK allowed on terminal byte only */
+       case STAT_RXDATA_NAK:
+               if (final_read)
+                       return 0;
+               return -EIO;
+
+       /* Arbitration lost */
+       case STAT_LOST_ARB_38:
+       case STAT_LOST_ARB_68:
+       case STAT_LOST_ARB_78:
+       case STAT_LOST_ARB_B0:
+               return -EAGAIN;
+
+       /* Being addressed as slave, should back off & listen */
+       case STAT_SLAVE_60:
+       case STAT_SLAVE_70:
+       case STAT_GENDATA_ACK:
+       case STAT_GENDATA_NAK:
+               return -EOPNOTSUPP;
+
+       /* Core busy as slave */
+       case STAT_SLAVE_80:
+       case STAT_SLAVE_88:
+       case STAT_SLAVE_A0:
+       case STAT_SLAVE_A8:
+       case STAT_SLAVE_LOST:
+       case STAT_SLAVE_NAK:
+       case STAT_SLAVE_ACK:
+               return -EOPNOTSUPP;
+
+       case STAT_TXDATA_NAK:
+               return -EIO;
+       case STAT_TXADDR_NAK:
+       case STAT_RXADDR_NAK:
+       case STAT_AD2W_NAK:
+               return -ENXIO;
+       default:
+               dev_err(i2c->dev, "unhandled state: %d\n", stat);
+               return -EIO;
+       }
+}
+
+static bool octeon_i2c_hlc_test_valid(struct octeon_i2c *i2c)
+{
+       return (__raw_readq(i2c->twsi_base + SW_TWSI) & SW_TWSI_V) == 0;
+}
+
+static bool octeon_i2c_hlc_test_ready(struct octeon_i2c *i2c, bool *first)
+{
+       /* check if valid bit is cleared */
+       if (octeon_i2c_hlc_test_valid(i2c))
+               return true;
+
+       if (*first) {
+               *first = false;
+               return false;
+       }
+
+       /*
+        * IRQ has signaled an event but valid bit isn't cleared.
+        * Sleep and retry once.
+        */
+       usleep_range(I2C_OCTEON_EVENT_WAIT, 2 * I2C_OCTEON_EVENT_WAIT);
+       return octeon_i2c_hlc_test_valid(i2c);
+}
+
+static void octeon_i2c_hlc_int_enable(struct octeon_i2c *i2c)
+{
+       octeon_i2c_write_int(i2c, TWSI_INT_ST_EN);
+}
+
+static void octeon_i2c_hlc_int_clear(struct octeon_i2c *i2c)
+{
+       /* clear ST/TS events, listen for neither */
+       octeon_i2c_write_int(i2c, TWSI_INT_ST_INT | TWSI_INT_TS_INT);
+}
+
 /**
- * octeon_i2c_start - send START to the bus
+ * octeon_i2c_hlc_wait - wait for an HLC operation to complete
  * @i2c: The struct octeon_i2c
  *
- * Returns 0 on success, otherwise a negative errno.
+ * Returns 0 on success, otherwise -ETIMEDOUT.
  */
-static int octeon_i2c_start(struct octeon_i2c *i2c)
+static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
 {
-       int result;
-       u8 data;
+       bool first = 1;
+       int time_left;
 
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
-                           TWSI_CTL_ENAB | TWSI_CTL_STA);
+       /*
+        * Some cn38xx boards don't assert the irq in the interrupt
+        * controller. So we must poll for the valid bit change.
+        */
+       if (i2c->broken_irq_mode) {
+               u64 end = get_jiffies_64() + i2c->adap.timeout;
 
-       result = octeon_i2c_wait(i2c);
-       if (result) {
-               if (octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT) == STAT_IDLE) {
+               while (!octeon_i2c_hlc_test_valid(i2c) &&
+                      time_before64(get_jiffies_64(), end))
+                       usleep_range(I2C_OCTEON_EVENT_WAIT / 2, I2C_OCTEON_EVENT_WAIT);
+
+               return octeon_i2c_hlc_test_valid(i2c) ? 0 : -ETIMEDOUT;
+       }
+
+       i2c->hlc_int_enable(i2c);
+       time_left = wait_event_timeout(i2c->queue,
+                                      octeon_i2c_hlc_test_ready(i2c, &first),
+                                      i2c->adap.timeout);
+       i2c->hlc_int_disable(i2c);
+       if (!time_left)
+               octeon_i2c_hlc_int_clear(i2c);
+
+       if (i2c->broken_irq_check && !time_left &&
+           octeon_i2c_hlc_test_valid(i2c)) {
+               dev_err(i2c->dev, "broken irq connection detected, switching to polling mode.\n");
+               i2c->broken_irq_mode = true;
+               return 0;
+       }
+
+       if (!time_left)
+               return -ETIMEDOUT;
+       return 0;
+}
+
+/* high-level-controller pure read of up to 8 bytes */
+static int octeon_i2c_hlc_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+       int i, j, ret = 0;
+       u64 cmd;
+
+       octeon_i2c_hlc_enable(i2c);
+       octeon_i2c_hlc_int_clear(i2c);
+
+       cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+       /* SIZE */
+       cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+       /* A */
+       cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+       if (msgs[0].flags & I2C_M_TEN)
+               cmd |= SW_TWSI_OP_10;
+       else
+               cmd |= SW_TWSI_OP_7;
+
+       octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
+       ret = octeon_i2c_hlc_wait(i2c);
+       if (ret)
+               goto err;
+
+       cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+       if ((cmd & SW_TWSI_R) == 0)
+               return -EAGAIN;
+
+       for (i = 0, j = msgs[0].len - 1; i  < msgs[0].len && i < 4; i++, j--)
+               msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+       if (msgs[0].len > 4) {
+               cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
+               for (i = 0; i  < msgs[0].len - 4 && i < 4; i++, j--)
+                       msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
+       }
+
+err:
+       return ret;
+}
+
+/* high-level-controller pure write of up to 8 bytes */
+static int octeon_i2c_hlc_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+       int i, j, ret = 0;
+       u64 cmd;
+
+       octeon_i2c_hlc_enable(i2c);
+       octeon_i2c_hlc_int_clear(i2c);
+
+       cmd = SW_TWSI_V | SW_TWSI_SOVR;
+       /* SIZE */
+       cmd |= (u64)(msgs[0].len - 1) << SW_TWSI_SIZE_SHIFT;
+       /* A */
+       cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+       if (msgs[0].flags & I2C_M_TEN)
+               cmd |= SW_TWSI_OP_10;
+       else
+               cmd |= SW_TWSI_OP_7;
+
+       for (i = 0, j = msgs[0].len - 1; i  < msgs[0].len && i < 4; i++, j--)
+               cmd |= (u64)msgs[0].buf[j] << (8 * i);
+
+       if (msgs[0].len > 4) {
+               u64 ext = 0;
+
+               for (i = 0; i < msgs[0].len - 4 && i < 4; i++, j--)
+                       ext |= (u64)msgs[0].buf[j] << (8 * i);
+               octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
+       }
+
+       octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
+       ret = octeon_i2c_hlc_wait(i2c);
+       if (ret)
+               goto err;
+
+       cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+       if ((cmd & SW_TWSI_R) == 0)
+               return -EAGAIN;
+
+       ret = octeon_i2c_check_status(i2c, false);
+
+err:
+       return ret;
+}
+
+/* high-level-controller composite write+read, msg0=addr, msg1=data */
+static int octeon_i2c_hlc_comp_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+       int i, j, ret = 0;
+       u64 cmd;
+
+       octeon_i2c_hlc_enable(i2c);
+
+       cmd = SW_TWSI_V | SW_TWSI_R | SW_TWSI_SOVR;
+       /* SIZE */
+       cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+       /* A */
+       cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+       if (msgs[0].flags & I2C_M_TEN)
+               cmd |= SW_TWSI_OP_10_IA;
+       else
+               cmd |= SW_TWSI_OP_7_IA;
+
+       if (msgs[0].len == 2) {
+               u64 ext = 0;
+
+               cmd |= SW_TWSI_EIA;
+               ext = (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+               cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+               octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
+       } else {
+               cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+       }
+
+       octeon_i2c_hlc_int_clear(i2c);
+       octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
+
+       ret = octeon_i2c_hlc_wait(i2c);
+       if (ret)
+               goto err;
+
+       cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+       if ((cmd & SW_TWSI_R) == 0)
+               return -EAGAIN;
+
+       for (i = 0, j = msgs[1].len - 1; i  < msgs[1].len && i < 4; i++, j--)
+               msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+
+       if (msgs[1].len > 4) {
+               cmd = __raw_readq(i2c->twsi_base + SW_TWSI_EXT);
+               for (i = 0; i  < msgs[1].len - 4 && i < 4; i++, j--)
+                       msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
+       }
+
+err:
+       return ret;
+}
+
+/* high-level-controller composite write+write, m[0]len<=2, m[1]len<=8 */
+static int octeon_i2c_hlc_comp_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
+{
+       bool set_ext = false;
+       int i, j, ret = 0;
+       u64 cmd, ext = 0;
+
+       octeon_i2c_hlc_enable(i2c);
+
+       cmd = SW_TWSI_V | SW_TWSI_SOVR;
+       /* SIZE */
+       cmd |= (u64)(msgs[1].len - 1) << SW_TWSI_SIZE_SHIFT;
+       /* A */
+       cmd |= (u64)(msgs[0].addr & 0x7full) << SW_TWSI_ADDR_SHIFT;
+
+       if (msgs[0].flags & I2C_M_TEN)
+               cmd |= SW_TWSI_OP_10_IA;
+       else
+               cmd |= SW_TWSI_OP_7_IA;
+
+       if (msgs[0].len == 2) {
+               cmd |= SW_TWSI_EIA;
+               ext |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+               set_ext = true;
+               cmd |= (u64)msgs[0].buf[1] << SW_TWSI_IA_SHIFT;
+       } else {
+               cmd |= (u64)msgs[0].buf[0] << SW_TWSI_IA_SHIFT;
+       }
+
+       for (i = 0, j = msgs[1].len - 1; i  < msgs[1].len && i < 4; i++, j--)
+               cmd |= (u64)msgs[1].buf[j] << (8 * i);
+
+       if (msgs[1].len > 4) {
+               for (i = 0; i < msgs[1].len - 4 && i < 4; i++, j--)
+                       ext |= (u64)msgs[1].buf[j] << (8 * i);
+               set_ext = true;
+       }
+       if (set_ext)
+               octeon_i2c_writeq_flush(ext, i2c->twsi_base + SW_TWSI_EXT);
+
+       octeon_i2c_hlc_int_clear(i2c);
+       octeon_i2c_writeq_flush(cmd, i2c->twsi_base + SW_TWSI);
+
+       ret = octeon_i2c_hlc_wait(i2c);
+       if (ret)
+               goto err;
+
+       cmd = __raw_readq(i2c->twsi_base + SW_TWSI);
+       if ((cmd & SW_TWSI_R) == 0)
+               return -EAGAIN;
+
+       ret = octeon_i2c_check_status(i2c, false);
+
+err:
+       return ret;
+}
+
+/* calculate and set clock divisors */
+static void octeon_i2c_set_clock(struct octeon_i2c *i2c)
+{
+       int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
+       int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
+
+       for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
+               /*
+                * An mdiv value of less than 2 seems to not work well
+                * with ds1337 RTCs, so we constrain it to larger values.
+                */
+               for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
                        /*
-                        * Controller refused to send start flag May
-                        * be a client is holding SDA low - let's try
-                        * to free it.
+                        * For given ndiv and mdiv values check the
+                        * two closest thp values.
                         */
-                       octeon_i2c_unblock(i2c);
-                       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
-                                           TWSI_CTL_ENAB | TWSI_CTL_STA);
-                       result = octeon_i2c_wait(i2c);
+                       tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
+                       tclk *= (1 << ndiv_idx);
+                       thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+
+                       for (inc = 0; inc <= 1; inc++) {
+                               thp_idx = thp_base + inc;
+                               if (thp_idx < 5 || thp_idx > 0xff)
+                                       continue;
+
+                               foscl = i2c->sys_freq / (2 * (thp_idx + 1));
+                               foscl = foscl / (1 << ndiv_idx);
+                               foscl = foscl / (mdiv_idx + 1) / 10;
+                               diff = abs(foscl - i2c->twsi_freq);
+                               if (diff < delta_hz) {
+                                       delta_hz = diff;
+                                       thp = thp_idx;
+                                       mdiv = mdiv_idx;
+                                       ndiv = ndiv_idx;
+                               }
+                       }
                }
-               if (result)
-                       return result;
+       }
+       octeon_i2c_reg_write(i2c, SW_TWSI_OP_TWSI_CLK, thp);
+       octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+}
+
+static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
+{
+       u8 status = 0;
+       int tries;
+
+       /* reset controller */
+       octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+
+       for (tries = 10; tries && status != STAT_IDLE; tries--) {
+               udelay(1);
+               status = octeon_i2c_stat_read(i2c);
+               if (status == STAT_IDLE)
+                       break;
        }
 
-       data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-       if ((data != STAT_START) && (data != STAT_RSTART)) {
-               dev_err(i2c->dev, "%s: bad status (0x%x)\n", __func__, data);
+       if (status != STAT_IDLE) {
+               dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n",
+                       __func__, status);
                return -EIO;
        }
 
+       /* toggle twice to force both teardowns */
+       octeon_i2c_hlc_enable(i2c);
+       octeon_i2c_hlc_disable(i2c);
        return 0;
 }
 
+static int octeon_i2c_recovery(struct octeon_i2c *i2c)
+{
+       int ret;
+
+       ret = i2c_recover_bus(&i2c->adap);
+       if (ret)
+               /* recover failed, try hardware re-init */
+               ret = octeon_i2c_init_lowlevel(i2c);
+       return ret;
+}
+
+/**
+ * octeon_i2c_start - send START to the bus
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_start(struct octeon_i2c *i2c)
+{
+       int ret;
+       u8 stat;
+
+       octeon_i2c_hlc_disable(i2c);
+
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STA);
+       ret = octeon_i2c_wait(i2c);
+       if (ret)
+               goto error;
+
+       stat = octeon_i2c_stat_read(i2c);
+       if (stat == STAT_START || stat == STAT_REP_START)
+               /* START successful, bail out */
+               return 0;
+
+error:
+       /* START failed, try to recover */
+       ret = octeon_i2c_recovery(i2c);
+       return (ret) ? ret : -EAGAIN;
+}
+
 /* send STOP to the bus */
 static void octeon_i2c_stop(struct octeon_i2c *i2c)
 {
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
-                           TWSI_CTL_ENAB | TWSI_CTL_STP);
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP);
 }
 
 /**
@@ -276,31 +879,21 @@ static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
                            const u8 *data, int length)
 {
        int i, result;
-       u8 tmp;
-
-       result = octeon_i2c_start(i2c);
-       if (result)
-               return result;
 
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, target << 1);
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+       octeon_i2c_data_write(i2c, target << 1);
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
 
        result = octeon_i2c_wait(i2c);
        if (result)
                return result;
 
        for (i = 0; i < length; i++) {
-               tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-
-               if ((tmp != STAT_TXADDR_ACK) && (tmp != STAT_TXDATA_ACK)) {
-                       dev_err(i2c->dev,
-                               "%s: bad status before write (0x%x)\n",
-                               __func__, tmp);
-                       return -EIO;
-               }
+               result = octeon_i2c_check_status(i2c, false);
+               if (result)
+                       return result;
 
-               octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, data[i]);
-               octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+               octeon_i2c_data_write(i2c, data[i]);
+               octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
 
                result = octeon_i2c_wait(i2c);
                if (result)
@@ -326,53 +919,52 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
                           u8 *data, u16 *rlength, bool recv_len)
 {
        int i, result, length = *rlength;
-       u8 tmp;
+       bool final_read = false;
 
-       if (length < 1)
-               return -EINVAL;
+       octeon_i2c_data_write(i2c, (target << 1) | 1);
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
 
-       result = octeon_i2c_start(i2c);
+       result = octeon_i2c_wait(i2c);
        if (result)
                return result;
 
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target << 1) | 1);
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
-       result = octeon_i2c_wait(i2c);
+       /* address OK ? */
+       result = octeon_i2c_check_status(i2c, false);
        if (result)
                return result;
 
        for (i = 0; i < length; i++) {
-               tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-
-               if ((tmp != STAT_RXDATA_ACK) && (tmp != STAT_RXADDR_ACK)) {
-                       dev_err(i2c->dev,
-                               "%s: bad status before read (0x%x)\n",
-                               __func__, tmp);
-                       return -EIO;
-               }
+               /*
+                * For the last byte to receive TWSI_CTL_AAK must not be set.
+                *
+                * A special case is I2C_M_RECV_LEN where we don't know the
+                * additional length yet. If recv_len is set we assume we're
+                * not reading the final byte and therefore need to set
+                * TWSI_CTL_AAK.
+                */
+               if ((i + 1 == length) && !(recv_len && i == 0))
+                       final_read = true;
 
-               if (i + 1 < length)
-                       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
-                                           TWSI_CTL_ENAB | TWSI_CTL_AAK);
+               /* clear iflg to allow next event */
+               if (final_read)
+                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
                else
-                       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
-                                           TWSI_CTL_ENAB);
+                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK);
 
                result = octeon_i2c_wait(i2c);
                if (result)
                        return result;
 
-               data[i] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
+               data[i] = octeon_i2c_data_read(i2c);
                if (recv_len && i == 0) {
-                       if (data[i] > I2C_SMBUS_BLOCK_MAX + 1) {
-                               dev_err(i2c->dev,
-                                       "%s: read len > I2C_SMBUS_BLOCK_MAX %d\n",
-                                       __func__, data[i]);
+                       if (data[i] > I2C_SMBUS_BLOCK_MAX + 1)
                                return -EPROTO;
-                       }
                        length += data[i];
                }
+
+               result = octeon_i2c_check_status(i2c, final_read);
+               if (result)
+                       return result;
        }
        *rlength = length;
        return 0;
@@ -392,13 +984,41 @@ static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
        struct octeon_i2c *i2c = i2c_get_adapdata(adap);
        int i, ret = 0;
 
+       if (num == 1) {
+               if (msgs[0].len > 0 && msgs[0].len <= 8) {
+                       if (msgs[0].flags & I2C_M_RD)
+                               ret = octeon_i2c_hlc_read(i2c, msgs);
+                       else
+                               ret = octeon_i2c_hlc_write(i2c, msgs);
+                       goto out;
+               }
+       } else if (num == 2) {
+               if ((msgs[0].flags & I2C_M_RD) == 0 &&
+                   (msgs[1].flags & I2C_M_RECV_LEN) == 0 &&
+                   msgs[0].len > 0 && msgs[0].len <= 2 &&
+                   msgs[1].len > 0 && msgs[1].len <= 8 &&
+                   msgs[0].addr == msgs[1].addr) {
+                       if (msgs[1].flags & I2C_M_RD)
+                               ret = octeon_i2c_hlc_comp_read(i2c, msgs);
+                       else
+                               ret = octeon_i2c_hlc_comp_write(i2c, msgs);
+                       goto out;
+               }
+       }
+
        for (i = 0; ret == 0 && i < num; i++) {
                struct i2c_msg *pmsg = &msgs[i];
 
-               dev_dbg(i2c->dev,
-                       "Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
-                        pmsg->flags & I2C_M_RD ? "read" : "write",
-                        pmsg->len, pmsg->addr, i + 1, num);
+               /* zero-length messages are not supported */
+               if (!pmsg->len) {
+                       ret = -EOPNOTSUPP;
+                       break;
+               }
+
+               ret = octeon_i2c_start(i2c);
+               if (ret)
+                       return ret;
+
                if (pmsg->flags & I2C_M_RD)
                        ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
                                              &pmsg->len, pmsg->flags & I2C_M_RECV_LEN);
@@ -407,102 +1027,105 @@ static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
                                               pmsg->len);
        }
        octeon_i2c_stop(i2c);
-
+out:
        return (ret != 0) ? ret : num;
 }
 
-static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
+static int octeon_i2c_get_scl(struct i2c_adapter *adap)
 {
-       return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
-              I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL;
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+       u64 state;
+
+       state = octeon_i2c_read_int(i2c);
+       return state & TWSI_INT_SCL;
 }
 
-static const struct i2c_algorithm octeon_i2c_algo = {
-       .master_xfer = octeon_i2c_xfer,
-       .functionality = octeon_i2c_functionality,
-};
+static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
 
-static struct i2c_adapter octeon_i2c_ops = {
-       .owner = THIS_MODULE,
-       .name = "OCTEON adapter",
-       .algo = &octeon_i2c_algo,
-       .timeout = HZ / 50,
-};
+       octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
+}
 
-/* calculate and set clock divisors */
-static void octeon_i2c_set_clock(struct octeon_i2c *i2c)
+static int octeon_i2c_get_sda(struct i2c_adapter *adap)
 {
-       int tclk, thp_base, inc, thp_idx, mdiv_idx, ndiv_idx, foscl, diff;
-       int thp = 0x18, mdiv = 2, ndiv = 0, delta_hz = 1000000;
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+       u64 state;
 
-       for (ndiv_idx = 0; ndiv_idx < 8 && delta_hz != 0; ndiv_idx++) {
-               /*
-                * An mdiv value of less than 2 seems to not work well
-                * with ds1337 RTCs, so we constrain it to larger values.
-                */
-               for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
-                       /*
-                        * For given ndiv and mdiv values check the
-                        * two closest thp values.
-                        */
-                       tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
-                       tclk *= (1 << ndiv_idx);
-                       thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+       state = octeon_i2c_read_int(i2c);
+       return state & TWSI_INT_SDA;
+}
 
-                       for (inc = 0; inc <= 1; inc++) {
-                               thp_idx = thp_base + inc;
-                               if (thp_idx < 5 || thp_idx > 0xff)
-                                       continue;
+static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
 
-                               foscl = i2c->sys_freq / (2 * (thp_idx + 1));
-                               foscl = foscl / (1 << ndiv_idx);
-                               foscl = foscl / (mdiv_idx + 1) / 10;
-                               diff = abs(foscl - i2c->twsi_freq);
-                               if (diff < delta_hz) {
-                                       delta_hz = diff;
-                                       thp = thp_idx;
-                                       mdiv = mdiv_idx;
-                                       ndiv = ndiv_idx;
-                               }
-                       }
-               }
-       }
-       octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+       /*
+        * The stop resets the state machine, does not _transmit_ STOP unless
+        * engine was active.
+        */
+       octeon_i2c_stop(i2c);
+
+       octeon_i2c_hlc_disable(i2c);
+       octeon_i2c_write_int(i2c, 0);
 }
 
-static int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c)
+static void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
 {
-       u8 status;
-       int tries;
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
 
-       /* disable high level controller, enable bus access */
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+       octeon_i2c_write_int(i2c, 0);
+}
 
-       /* reset controller */
-       octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+static struct i2c_bus_recovery_info octeon_i2c_recovery_info = {
+       .recover_bus = i2c_generic_scl_recovery,
+       .get_scl = octeon_i2c_get_scl,
+       .set_scl = octeon_i2c_set_scl,
+       .get_sda = octeon_i2c_get_sda,
+       .prepare_recovery = octeon_i2c_prepare_recovery,
+       .unprepare_recovery = octeon_i2c_unprepare_recovery,
+};
 
-       for (tries = 10; tries; tries--) {
-               udelay(1);
-               status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-               if (status == STAT_IDLE)
-                       return 0;
-       }
-       dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", __func__, status);
-       return -EIO;
+static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
+{
+       return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
+              I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL;
 }
 
+static const struct i2c_algorithm octeon_i2c_algo = {
+       .master_xfer = octeon_i2c_xfer,
+       .functionality = octeon_i2c_functionality,
+};
+
+static struct i2c_adapter octeon_i2c_ops = {
+       .owner = THIS_MODULE,
+       .name = "OCTEON adapter",
+       .algo = &octeon_i2c_algo,
+};
+
 static int octeon_i2c_probe(struct platform_device *pdev)
 {
        struct device_node *node = pdev->dev.of_node;
+       int irq, result = 0, hlc_irq = 0;
        struct resource *res_mem;
        struct octeon_i2c *i2c;
-       int irq, result = 0;
-
-       /* All adaptors have an irq.  */
-       irq = platform_get_irq(pdev, 0);
-       if (irq < 0)
-               return irq;
+       bool cn78xx_style;
+
+       cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi");
+       if (cn78xx_style) {
+               hlc_irq = platform_get_irq(pdev, 0);
+               if (hlc_irq < 0)
+                       return hlc_irq;
+
+               irq = platform_get_irq(pdev, 2);
+               if (irq < 0)
+                       return irq;
+       } else {
+               /* All adaptors have an irq.  */
+               irq = platform_get_irq(pdev, 0);
+               if (irq < 0)
+                       return irq;
+       }
 
        i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
        if (!i2c) {
@@ -537,6 +1160,31 @@ static int octeon_i2c_probe(struct platform_device *pdev)
 
        i2c->irq = irq;
 
+       if (cn78xx_style) {
+               i2c->hlc_irq = hlc_irq;
+
+               i2c->int_enable = octeon_i2c_int_enable78;
+               i2c->int_disable = octeon_i2c_int_disable78;
+               i2c->hlc_int_enable = octeon_i2c_hlc_int_enable78;
+               i2c->hlc_int_disable = octeon_i2c_hlc_int_disable78;
+
+               irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN);
+               irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN);
+
+               result = devm_request_irq(&pdev->dev, i2c->hlc_irq,
+                                         octeon_i2c_hlc_isr78, 0,
+                                         DRV_NAME, i2c);
+               if (result < 0) {
+                       dev_err(i2c->dev, "failed to attach interrupt\n");
+                       goto out;
+               }
+       } else {
+               i2c->int_enable = octeon_i2c_int_enable;
+               i2c->int_disable = octeon_i2c_int_disable;
+               i2c->hlc_int_enable = octeon_i2c_hlc_int_enable;
+               i2c->hlc_int_disable = octeon_i2c_int_disable;
+       }
+
        result = devm_request_irq(&pdev->dev, i2c->irq,
                                  octeon_i2c_isr, 0, DRV_NAME, i2c);
        if (result < 0) {
@@ -544,6 +1192,9 @@ static int octeon_i2c_probe(struct platform_device *pdev)
                goto out;
        }
 
+       if (OCTEON_IS_MODEL(OCTEON_CN38XX))
+               i2c->broken_irq_check = true;
+
        result = octeon_i2c_init_lowlevel(i2c);
        if (result) {
                dev_err(i2c->dev, "init low level failed\n");
@@ -553,6 +1204,9 @@ static int octeon_i2c_probe(struct platform_device *pdev)
        octeon_i2c_set_clock(i2c);
 
        i2c->adap = octeon_i2c_ops;
+       i2c->adap.timeout = msecs_to_jiffies(2);
+       i2c->adap.retries = 5;
+       i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info;
        i2c->adap.dev.parent = &pdev->dev;
        i2c->adap.dev.of_node = node;
        i2c_set_adapdata(&i2c->adap, i2c);
@@ -580,6 +1234,7 @@ static int octeon_i2c_remove(struct platform_device *pdev)
 
 static const struct of_device_id octeon_i2c_match[] = {
        { .compatible = "cavium,octeon-3860-twsi", },
+       { .compatible = "cavium,octeon-7890-twsi", },
        {},
 };
 MODULE_DEVICE_TABLE(of, octeon_i2c_match);