i2c: octeon: Split the driver into two parts

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>

1 files changed, 1 insertions, 972 deletions

diff --git a/drivers/i2c/busses/i2c-octeon-platdrv.c b/drivers/i2c/busses/i2c-octeon-platdrv.c
index b75d2da79b27..53fa9a0d96bb 100644
--- a/drivers/i2c/busses/i2c-octeon-platdrv.c
+++ b/drivers/i2c/busses/i2c-octeon-platdrv.c
@@ -24,191 +24,10 @@
 #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) |