i2c: octeon: Split the driver into two parts
authorJan Glauber <jglauber@cavium.com>
Wed, 24 Aug 2016 21:25:43 +0000 (23:25 +0200)
committerWolfram Sang <wsa@the-dreams.de>
Thu, 25 Aug 2016 22:41:54 +0000 (00:41 +0200)
Move common functionality into a separate file in preparation of the
re-use from the ThunderX i2c driver.

Functions are slightly re-ordered but no other changes are included.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/busses/Makefile
drivers/i2c/busses/i2c-octeon-core.c [new file with mode: 0644]
drivers/i2c/busses/i2c-octeon-core.h [new file with mode: 0644]
drivers/i2c/busses/i2c-octeon-platdrv.c

index f2c9c6f..f975263 100644 (file)
@@ -91,7 +91,8 @@ obj-$(CONFIG_I2C_UNIPHIER)    += i2c-uniphier.o
 obj-$(CONFIG_I2C_UNIPHIER_F)   += i2c-uniphier-f.o
 obj-$(CONFIG_I2C_VERSATILE)    += i2c-versatile.o
 obj-$(CONFIG_I2C_WMT)          += i2c-wmt.o
-obj-$(CONFIG_I2C_OCTEON)       += i2c-octeon-platdrv.o
+i2c-octeon-objs := i2c-octeon-core.o i2c-octeon-platdrv.o
+obj-$(CONFIG_I2C_OCTEON)       += i2c-octeon.o
 obj-$(CONFIG_I2C_XILINX)       += i2c-xiic.o
 obj-$(CONFIG_I2C_XLR)          += i2c-xlr.o
 obj-$(CONFIG_I2C_XLP9XX)       += i2c-xlp9xx.o
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
new file mode 100644 (file)
index 0000000..23384ef
--- /dev/null
@@ -0,0 +1,810 @@
+/*
+ * (C) Copyright 2009-2010
+ * Nokia Siemens Networks, michael.lawnick.ext@nsn.com
+ *
+ * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
+ *
+ * This file contains the shared part of the driver for the i2c adapter in
+ * Cavium Networks' OCTEON processors and ThunderX SOCs.
+ *
+ * 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/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include "i2c-octeon-core.h"
+
+/* interrupt service routine */
+irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
+{
+       struct octeon_i2c *i2c = dev_id;
+
+       i2c->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 bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
+{
+       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);
+}
+
+/**
+ * octeon_i2c_wait - wait for the IFLG to be set
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_wait(struct octeon_i2c *i2c)
+{
+       long time_left;
+       bool first = 1;
+
+       /*
+        * 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);
+       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 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_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);
+}
+
+/*
+ * Cleanup low-level state & enable high-level controller.
+ */
+static void octeon_i2c_hlc_enable(struct octeon_i2c *i2c)
+{
+       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;
+
+               /* 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;
+               }
+
+               /* spin until any start/stop has finished */
+               udelay(10);
+       }
+       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);
+}
+
+/**
+ * octeon_i2c_hlc_wait - wait for an HLC operation to complete
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns 0 on success, otherwise -ETIMEDOUT.
+ */
+static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
+{
+       bool first = 1;
+       int time_left;
+
+       /*
+        * 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;
+
+               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;
+}
+
+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 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_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP);
+}
+
+/**
+ * octeon_i2c_read - receive data from the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the location to store the data
+ * @rlength: Length of the data
+ * @recv_len: flag for length byte
+ *
+ * The address is sent over the bus, then the data is read.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
+                          u8 *data, u16 *rlength, bool recv_len)
+{
+       int i, result, length = *rlength;
+       bool final_read = false;
+
+       octeon_i2c_data_write(i2c, (target << 1) | 1);
+       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+       result = octeon_i2c_wait(i2c);
+       if (result)
+               return result;
+
+       /* address OK ? */
+       result = octeon_i2c_check_status(i2c, false);
+       if (result)
+               return result;
+
+       for (i = 0; i < length; i++) {
+               /*
+                * 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;
+
+               /* clear iflg to allow next event */
+               if (final_read)
+                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+               else
+                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK);
+
+               result = octeon_i2c_wait(i2c);
+               if (result)
+                       return result;
+
+               data[i] = octeon_i2c_data_read(i2c);
+               if (recv_len && i == 0) {
+                       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;
+}
+
+/**
+ * octeon_i2c_write - send data to the bus via low-level controller
+ * @i2c: The struct octeon_i2c
+ * @target: Target address
+ * @data: Pointer to the data to be sent
+ * @length: Length of the data
+ *
+ * The address is sent over the bus, then the data.
+ *
+ * Returns 0 on success, otherwise a negative errno.
+ */
+static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
+                           const u8 *data, int length)
+{
+       int i, result;
+
+       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++) {
+               result = octeon_i2c_check_status(i2c, false);
+               if (result)
+                       return result;
+
+               octeon_i2c_data_write(i2c, data[i]);
+               octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
+
+               result = octeon_i2c_wait(i2c);
+               if (result)
+                       return result;
+       }
+
+       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;
+}
+
+/**
+ * octeon_i2c_xfer - The driver's master_xfer function
+ * @adap: Pointer to the i2c_adapter structure
+ * @msgs: Pointer to the messages to be processed
+ * @num: Length of the MSGS array
+ *
+ * Returns the number of messages processed, or a negative errno on failure.
+ */
+int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+       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];
+
+               /* 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);
+               else
+                       ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
+                                              pmsg->len);
+       }
+       octeon_i2c_stop(i2c);
+out:
+       return (ret != 0) ? ret : num;
+}
+
+/* calculate and set clock divisors */
+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--) {
+                       /*
+                        * 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;
+
+                       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;
+                               }
+                       }
+               }
+       }
+       octeon_i2c_reg_write(i2c, SW_TWSI_OP_TWSI_CLK, thp);
+       octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
+}
+
+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;
+       }
+
+       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_get_scl(struct i2c_adapter *adap)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+       u64 state;
+
+       state = octeon_i2c_read_int(i2c);
+       return state & TWSI_INT_SCL;
+}
+
+static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+
+       octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
+}
+
+static int octeon_i2c_get_sda(struct i2c_adapter *adap)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+       u64 state;
+
+       state = octeon_i2c_read_int(i2c);
+       return state & TWSI_INT_SDA;
+}
+
+static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+
+       /*
+        * 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 void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+
+       octeon_i2c_write_int(i2c, 0);
+}
+
+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,
+};
diff --git a/drivers/i2c/busses/i2c-octeon-core.h b/drivers/i2c/busses/i2c-octeon-core.h
new file mode 100644 (file)
index 0000000..81c6a81
--- /dev/null
@@ -0,0 +1,197 @@
+#include <linux/atomic.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/pci.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 */
+
+/* Controller extended opcode word (bits 34:32) */
+#define SW_TWSI_EOP_SHIFT      32
+#define SW_TWSI_EOP_TWSI_DATA  (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_CTL   (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_CLKCTL        (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_STAT  (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
+#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    /* 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 */
+
+/* Status values */
+#define STAT_ERROR             0x00
+#define STAT_START             0x08
+#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 inline void octeon_i2c_writeq_flush(u64 val, void __iomem *addr)
+{
+       __raw_writeq(val, addr);
+       __raw_readq(addr);      /* wait for write to land */
+}
+
+/**
+ * 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 inline void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
+{
+       u64 tmp;
+
+       __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
+       do {
+               tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
+       } 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_reg_read - read lower bits of an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ *
+ * Returns the data.
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static inline u8 octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg)
+{
+       u64 tmp;
+
+       __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
+       do {
+               tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
+       } while ((tmp & SW_TWSI_V) != 0);
+
+       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 inline 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
+ * @data: Value to be written
+ */
+static inline void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
+{
+       octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT);
+}
+
+/* Prototypes */
+irqreturn_t octeon_i2c_isr(int irq, void *dev_id);
+int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
+int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c);
+void octeon_i2c_set_clock(struct octeon_i2c *i2c);
+extern struct i2c_bus_recovery_info octeon_i2c_recovery_info;
index b75d2da..53fa9a0 100644 (file)
 #include <linux/of.h>
 
 #include <asm/octeon/octeon.h>
+#include "i2c-octeon-core.h"
 
 #define DRV_NAME "i2c-octeon"
 
-/* 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 */
-
-/* Controller extended opcode word (bits 34:32) */
-#define SW_TWSI_EOP_SHIFT      32
-#define SW_TWSI_EOP_TWSI_DATA  (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_CTL   (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_CLKCTL        (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
-#define SW_TWSI_EOP_TWSI_STAT  (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
-#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    /* 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 */
-
-/* Status values */
-#define STAT_ERROR             0x00
-#define STAT_START             0x08
-#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_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_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
-{
-       u64 tmp;
-
-       __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI);
-       do {
-               tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
-       } 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_reg_read - read lower bits of an I2C core register
- * @i2c: The struct octeon_i2c
- * @eop_reg: Register selector
- *
- * Returns the data.
- *
- * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
- */
-static u8 octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg)
-{
-       u64 tmp;
-
-       __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI);
-       do {
-               tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
-       } while ((tmp & SW_TWSI_V) != 0);
-
-       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
- * @data: Value to be written
- */
-static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
-{
-       octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT);
-}
-
 /**
  * octeon_i2c_int_enable - enable the CORE interrupt
  * @i2c: The struct octeon_i2c
@@ -280,58 +99,6 @@ 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_hlc_enable(struct octeon_i2c *i2c)
-{
-       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;
-
-               /* 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;
-               }
-
-               /* spin until any start/stop has finished */
-               udelay(10);
-       }
-       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 */
-static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
-{
-       struct octeon_i2c *i2c = dev_id;
-
-       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)
 {
@@ -343,749 +110,11 @@ static irqreturn_t octeon_i2c_hlc_isr78(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
-static bool octeon_i2c_test_iflg(struct octeon_i2c *i2c)
-{
-       return (octeon_i2c_ctl_read(i2c) & TWSI_CTL_IFLG);
-}
-
-static bool octeon_i2c_test_ready(struct octeon_i2c *i2c, bool *first)
-{
-       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);
-}
-
-/**
- * octeon_i2c_wait - wait for the IFLG to be set
- * @i2c: The struct octeon_i2c
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_wait(struct octeon_i2c *i2c)
-{
-       long time_left;
-       bool first = 1;
-
-       /*
-        * 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);
-       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_hlc_wait - wait for an HLC operation to complete
- * @i2c: The struct octeon_i2c
- *
- * Returns 0 on success, otherwise -ETIMEDOUT.
- */
-static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
-{
-       bool first = 1;
-       int time_left;
-
-       /*
-        * 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;
-
-               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--) {
-                       /*
-                        * 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;
-
-                       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;
-                               }
-                       }
-               }
-       }
-       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;
-       }
-
-       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_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_STP);
-}
-
-/**
- * octeon_i2c_write - send data to the bus via low-level controller
- * @i2c: The struct octeon_i2c
- * @target: Target address
- * @data: Pointer to the data to be sent
- * @length: Length of the data
- *
- * The address is sent over the bus, then the data.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
-                           const u8 *data, int length)
-{
-       int i, result;
-
-       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++) {
-               result = octeon_i2c_check_status(i2c, false);
-               if (result)
-                       return result;
-
-               octeon_i2c_data_write(i2c, data[i]);
-               octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
-
-               result = octeon_i2c_wait(i2c);
-               if (result)
-                       return result;
-       }
-
-       return 0;
-}
-
-/**
- * octeon_i2c_read - receive data from the bus via low-level controller
- * @i2c: The struct octeon_i2c
- * @target: Target address
- * @data: Pointer to the location to store the data
- * @rlength: Length of the data
- * @recv_len: flag for length byte
- *
- * The address is sent over the bus, then the data is read.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
-                          u8 *data, u16 *rlength, bool recv_len)
-{
-       int i, result, length = *rlength;
-       bool final_read = false;
-
-       octeon_i2c_data_write(i2c, (target << 1) | 1);
-       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
-
-       result = octeon_i2c_wait(i2c);
-       if (result)
-               return result;
-
-       /* address OK ? */
-       result = octeon_i2c_check_status(i2c, false);
-       if (result)
-               return result;
-
-       for (i = 0; i < length; i++) {
-               /*
-                * 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;
-
-               /* clear iflg to allow next event */
-               if (final_read)
-                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB);
-               else
-                       octeon_i2c_ctl_write(i2c, TWSI_CTL_ENAB | TWSI_CTL_AAK);
-
-               result = octeon_i2c_wait(i2c);
-               if (result)
-                       return result;
-
-               data[i] = octeon_i2c_data_read(i2c);
-               if (recv_len && i == 0) {
-                       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;
-}
-
-/**
- * octeon_i2c_xfer - The driver's master_xfer function
- * @adap: Pointer to the i2c_adapter structure
- * @msgs: Pointer to the messages to be processed
- * @num: Length of the MSGS array
- *
- * Returns the number of messages processed, or a negative errno on failure.
- */
-static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
-                          int num)
-{
-       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];
-
-               /* 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);
-               else
-                       ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
-                                              pmsg->len);
-       }
-       octeon_i2c_stop(i2c);
-out:
-       return (ret != 0) ? ret : num;
-}
-
-static int octeon_i2c_get_scl(struct i2c_adapter *adap)
-{
-       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
-       u64 state;
-
-       state = octeon_i2c_read_int(i2c);
-       return state & TWSI_INT_SCL;
-}
-
-static void octeon_i2c_set_scl(struct i2c_adapter *adap, int val)
-{
-       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
-
-       octeon_i2c_write_int(i2c, TWSI_INT_SCL_OVR);
-}
-
-static int octeon_i2c_get_sda(struct i2c_adapter *adap)
-{
-       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
-       u64 state;
-
-       state = octeon_i2c_read_int(i2c);
-       return state & TWSI_INT_SDA;
-}
-
-static void octeon_i2c_prepare_recovery(struct i2c_adapter *adap)
-{
-       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
-
-       /*
-        * 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 void octeon_i2c_unprepare_recovery(struct i2c_adapter *adap)
-{
-       struct octeon_i2c *i2c = i2c_get_adapdata(adap);
-
-       octeon_i2c_write_int(i2c, 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,
-};
-
 static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
 {
        return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |