[RFC PATCH 1/8] i2c-octeon: Cleanup i2c-octeon driver

From: Jan Glauber
Date: Thu Feb 18 2016 - 03:23:03 EST

Cleanup only without functional change.

Signed-off-by: Jan Glauber <jglauber@xxxxxxxxxx>
Acked-by: David Daney <ddaney@xxxxxxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-octeon.c | 442 +++++++++++++++++++++-------------------
1 file changed, 230 insertions(+), 212 deletions(-)

diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
index 32914ab..1f14094 100644
--- a/drivers/i2c/busses/i2c-octeon.c
+++ b/drivers/i2c/busses/i2c-octeon.c
@@ -2,7 +2,7 @@
* (C) Copyright 2009-2010
* Nokia Siemens Networks, michael.lawnick.ext@xxxxxxx
*
- * Portions Copyright (C) 2010, 2011 Cavium Networks, Inc.
+ * Portions Copyright (C) 2010 - 2016 Cavium, Inc.
*
* This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
*
@@ -24,99 +24,154 @@

#include <asm/octeon/octeon.h>

-#define DRV_NAME "i2c-octeon"
+#define DRV_NAME "i2c-octeon"

-/* The previous out-of-tree version was implicitly version 1.0. */
-#define DRV_VERSION "2.0"
+/* Register offsets */
+#define SW_TWSI 0x00
+#define TWSI_INT 0x10
+#define SW_TWSI_EXT 0x18

-/* register offsets */
-#define SW_TWSI 0x00
-#define TWSI_INT 0x10
+#define INT_ENA_ST 0x1
+#define INT_ENA_TS 0x2
+#define INT_ENA_CORE 0x4

/* Controller command patterns */
-#define SW_TWSI_V 0x8000000000000000ull
-#define SW_TWSI_EOP_TWSI_DATA 0x0C00000100000000ull
-#define SW_TWSI_EOP_TWSI_CTL 0x0C00000200000000ull
-#define SW_TWSI_EOP_TWSI_CLKCTL 0x0C00000300000000ull
-#define SW_TWSI_EOP_TWSI_STAT 0x0C00000300000000ull
-#define SW_TWSI_EOP_TWSI_RST 0x0C00000700000000ull
-#define SW_TWSI_OP_TWSI_CLK 0x0800000000000000ull
-#define SW_TWSI_R 0x0100000000000000ull
+#define SW_TWSI_V (1ULL << 63)
+#define SW_TWSI_EIA (1ULL << 61)
+#define SW_TWSI_R (1ULL << 56)
+#define SW_TWSI_SOVR (1ULL << 55)
+#define SW_TWSI_OP_7 (0ULL << 57)
+#define SW_TWSI_OP_7_IA (1ULL << 57)
+#define SW_TWSI_OP_10 (2ULL << 57)
+#define SW_TWSI_OP_10_IA (3ULL << 57)
+#define SW_TWSI_OP_TWSI_CLK (1ULL << 59)
+#define SW_TWSI_SIZE_SHIFT 52
+#define SW_TWSI_A_SHIFT 40
+#define SW_TWSI_IA_SHIFT 32
+#define SW_TWSI_EOP_TWSI_DATA 0x0C00000100000000ULL
+#define SW_TWSI_EOP_TWSI_CTL 0x0C00000200000000ULL
+#define SW_TWSI_EOP_TWSI_CLKCTL 0x0C00000300000000ULL
+#define SW_TWSI_EOP_TWSI_STAT 0x0C00000300000000ULL
+#define SW_TWSI_EOP_TWSI_RST 0x0C00000700000000ULL

/* Controller command and status bits */
-#define TWSI_CTL_CE 0x80
-#define TWSI_CTL_ENAB 0x40
-#define TWSI_CTL_STA 0x20
-#define TWSI_CTL_STP 0x10
-#define TWSI_CTL_IFLG 0x08
-#define TWSI_CTL_AAK 0x04
+#define TWSI_CTL_CE 0x80 /* High level controller enable */
+#define TWSI_CTL_ENAB 0x40 /* Bus enable */
+#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
+#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
+#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
+#define TWSI_CTL_AAK 0x04 /* Assert ACK */

/* Some status values */
-#define STAT_START 0x08
-#define STAT_RSTART 0x10
-#define STAT_TXADDR_ACK 0x18
-#define STAT_TXDATA_ACK 0x28
-#define STAT_RXADDR_ACK 0x40
-#define STAT_RXDATA_ACK 0x50
-#define STAT_IDLE 0xF8
+#define STAT_ERROR 0x00
+#define STAT_START 0x08
+#define STAT_RSTART 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 ST_INT 0x01
+#define TS_INT 0x02
+#define CORE_INT 0x04
+#define ST_EN 0x10
+#define TS_EN 0x20
+#define CORE_EN 0x40
+#define SDA_OVR 0x100
+#define SCL_OVR 0x200
+#define SDA 0x400
+#define SCL 0x800

struct octeon_i2c {
- wait_queue_head_t queue;
- struct i2c_adapter adap;
- int irq;
- u32 twsi_freq;
- int sys_freq;
- resource_size_t twsi_phys;
- void __iomem *twsi_base;
- resource_size_t regsize;
- struct device *dev;
+ wait_queue_head_t queue;
+ struct i2c_adapter adap;
+ int irq;
+ u32 twsi_freq;
+ int sys_freq;
+ void __iomem *twsi_base;
+ struct device *dev;
};

/**
- * octeon_i2c_write_sw - write an I2C core register.
- * @i2c: The struct octeon_i2c.
- * @eop_reg: Register selector.
- * @data: Value to be written.
+ * octeon_i2c_write_sw - write an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ * @data: Value to be written
*
* The I2C core registers are accessed indirectly via the SW_TWSI CSR.
*/
-static void octeon_i2c_write_sw(struct octeon_i2c *i2c,
- u64 eop_reg,
- u8 data)
+static void octeon_i2c_write_sw(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 {
+ do
tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
- } while ((tmp & SW_TWSI_V) != 0);
+ while ((tmp & SW_TWSI_V) != 0);
}

/**
- * octeon_i2c_read_sw - write an I2C core register.
- * @i2c: The struct octeon_i2c.
- * @eop_reg: Register selector.
+ * octeon_i2c_read_sw64 - read 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_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
+static u64 octeon_i2c_read_sw64(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 {
+ do
tmp = __raw_readq(i2c->twsi_base + SW_TWSI);
- } while ((tmp & SW_TWSI_V) != 0);
+ while ((tmp & SW_TWSI_V) != 0);

- return tmp & 0xFF;
+ return tmp;
+}
+
+/**
+ * octeon_i2c_read_sw - 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_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
+{
+ return octeon_i2c_read_sw64(i2c, eop_reg);
}

/**
* octeon_i2c_write_int - write the TWSI_INT register
- * @i2c: The struct octeon_i2c.
- * @data: Value to be written.
+ * @i2c: The struct octeon_i2c
+ * @data: Value to be written
*/
static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
{
@@ -125,57 +180,52 @@ static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
}

/**
- * octeon_i2c_int_enable - enable the TS interrupt.
- * @i2c: The struct octeon_i2c.
+ * octeon_i2c_int_enable - enable the CORE interrupt
+ * @i2c: The struct octeon_i2c
*
- * The interrupt will be asserted when there is non-STAT_IDLE state in
- * the SW_TWSI_EOP_TWSI_STAT register.
+ * The interrupt will be asserted when there is non-STAT_IDLE state in the
+ * SW_TWSI_EOP_TWSI_STAT register.
*/
static void octeon_i2c_int_enable(struct octeon_i2c *i2c)
{
- octeon_i2c_write_int(i2c, 0x40);
+ octeon_i2c_write_int(i2c, CORE_EN);
}

-/**
- * octeon_i2c_int_disable - disable the TS interrupt.
- * @i2c: The struct octeon_i2c.
- */
+/* disable the CORE interrupt */
static void octeon_i2c_int_disable(struct octeon_i2c *i2c)
{
- octeon_i2c_write_int(i2c, 0);
+ /* clear TS/ST/IFLG events */
+ octeon_i2c_write_int(i2c, TS_INT | ST_INT);
}

/**
- * octeon_i2c_unblock - unblock the bus.
- * @i2c: The struct octeon_i2c.
+ * bitbang_unblock - unblock the bus
+ * @i2c: The struct octeon_i2c
*
- * If there was a reset while a device was driving 0 to bus,
- * bus is blocked. We toggle it free manually by some clock
- * cycles and send a stop.
+ * If there was a reset while a device was driving 0 to bus, bus is blocked.
+ * We toggle it free manually by some clock cycles and send a stop.
*/
-static void octeon_i2c_unblock(struct octeon_i2c *i2c)
+static void bitbang_unblock(struct octeon_i2c *i2c)
{
int i;

dev_dbg(i2c->dev, "%s\n", __func__);
+
for (i = 0; i < 9; i++) {
- octeon_i2c_write_int(i2c, 0x0);
+ octeon_i2c_write_int(i2c, 0);
udelay(5);
- octeon_i2c_write_int(i2c, 0x200);
+ octeon_i2c_write_int(i2c, SCL_OVR);
udelay(5);
}
- octeon_i2c_write_int(i2c, 0x300);
+ /* hand-crank a STOP */
+ octeon_i2c_write_int(i2c, SDA_OVR | SCL_OVR);
udelay(5);
- octeon_i2c_write_int(i2c, 0x100);
+ octeon_i2c_write_int(i2c, SDA_OVR);
udelay(5);
- octeon_i2c_write_int(i2c, 0x0);
+ octeon_i2c_write_int(i2c, 0);
}

-/**
- * octeon_i2c_isr - the interrupt service routine.
- * @int: The irq, unused.
- * @dev_id: Our struct octeon_i2c.
- */
+/* interrupt service routine */
static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
{
struct octeon_i2c *i2c = dev_id;
@@ -186,15 +236,15 @@ static irqreturn_t octeon_i2c_isr(int irq, void *dev_id)
return IRQ_HANDLED;
}

-
static int octeon_i2c_test_iflg(struct octeon_i2c *i2c)
{
- return (octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_CTL) & TWSI_CTL_IFLG) != 0;
+ return (octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_CTL)
+ & TWSI_CTL_IFLG) != 0;
}

/**
- * octeon_i2c_wait - wait for the IFLG to be set.
- * @i2c: The struct octeon_i2c.
+ * octeon_i2c_wait - wait for the IFLG to be set
+ * @i2c: The struct octeon_i2c
*
* Returns 0 on success, otherwise a negative errno.
*/
@@ -203,34 +253,64 @@ static int octeon_i2c_wait(struct octeon_i2c *i2c)
long result;

octeon_i2c_int_enable(i2c);
-
- result = wait_event_timeout(i2c->queue,
- octeon_i2c_test_iflg(i2c),
- i2c->adap.timeout);
-
+ result = wait_event_timeout(i2c->queue, octeon_i2c_test_iflg(i2c),
+ i2c->adap.timeout);
octeon_i2c_int_disable(i2c);
-
- if (result == 0) {
+ if (!result) {
dev_dbg(i2c->dev, "%s: timeout\n", __func__);
return -ETIMEDOUT;
}
-
return 0;
}

+/* send STOP to the bus */
+static void octeon_i2c_stop(struct octeon_i2c *i2c)
+{
+ u8 data;
+
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
+ TWSI_CTL_ENAB | TWSI_CTL_STP);
+
+ data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+
+ if (data != STAT_IDLE)
+ dev_err(i2c->dev, "%s: bad status(0x%x)\n", __func__, data);
+}
+
+static int octeon_i2c_initlowlevel(struct octeon_i2c *i2c)
+{
+ u8 status;
+ int tries;
+
+ /* disable high level controller, enable bus access */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
+
+ /* reset controller */
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
+
+ for (tries = 10; tries; tries--) {
+ udelay(1);
+ status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+ if (status == STAT_IDLE)
+ return 0;
+ }
+ dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", __func__, status);
+ return -EIO;
+}
+
/**
- * octeon_i2c_start - send START to the bus.
- * @i2c: The struct octeon_i2c.
+ * 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)
{
- u8 data;
int result;
+ u8 data;

octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_STA);
+ TWSI_CTL_ENAB | TWSI_CTL_STA);

result = octeon_i2c_wait(i2c);
if (result) {
@@ -240,10 +320,9 @@ static int octeon_i2c_start(struct octeon_i2c *i2c)
* be a client is holding SDA low - let's try
* to free it.
*/
- octeon_i2c_unblock(i2c);
+ bitbang_unblock(i2c);
octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
TWSI_CTL_ENAB | TWSI_CTL_STA);
-
result = octeon_i2c_wait(i2c);
}
if (result)
@@ -255,47 +334,24 @@ static int octeon_i2c_start(struct octeon_i2c *i2c)
dev_err(i2c->dev, "%s: bad status (0x%x)\n", __func__, data);
return -EIO;
}
-
- return 0;
-}
-
-/**
- * octeon_i2c_stop - send STOP to the bus.
- * @i2c: The struct octeon_i2c.
- *
- * Returns 0 on success, otherwise a negative errno.
- */
-static int octeon_i2c_stop(struct octeon_i2c *i2c)
-{
- u8 data;
-
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_STP);
-
- data = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
-
- if (data != STAT_IDLE) {
- dev_err(i2c->dev, "%s: bad status(0x%x)\n", __func__, data);
- return -EIO;
- }
return 0;
}

/**
- * octeon_i2c_write - send data to the bus.
- * @i2c: The struct octeon_i2c.
- * @target: Target address.
- * @data: Pointer to the data to be sent.
- * @length: Length of the data.
+ * 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)
+ u8 *data, int length)
{
- int i, result;
+ int result, i;
u8 tmp;

result = octeon_i2c_start(i2c);
@@ -311,6 +367,7 @@ static int octeon_i2c_write(struct octeon_i2c *i2c, int target,

for (i = 0; i < length; i++) {
tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+
if ((tmp != STAT_TXADDR_ACK) && (tmp != STAT_TXDATA_ACK)) {
dev_err(i2c->dev,
"%s: bad status before write (0x%x)\n",
@@ -330,19 +387,20 @@ static int octeon_i2c_write(struct octeon_i2c *i2c, int target,
}

/**
- * octeon_i2c_read - receive data from the bus.
- * @i2c: The struct octeon_i2c.
- * @target: Target address.
- * @data: Pointer to the location to store the datae .
- * @length: Length of the data.
+ * 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
*
* 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, int length)
+static int octeon_i2c_read(struct octeon_i2c *i2c, int target, u8 *data,
+ u16 *rlength)
{
+ int length = *rlength;
int i, result;
u8 tmp;

@@ -353,15 +411,14 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
if (result)
return result;

- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, (target<<1) | 1);
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
+ octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_DATA, TWSI_CTL_ENAB);
result = octeon_i2c_wait(i2c);
if (result)
return result;

for (i = 0; i < length; i++) {
tmp = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
+
if ((tmp != STAT_RXDATA_ACK) && (tmp != STAT_RXADDR_ACK)) {
dev_err(i2c->dev,
"%s: bad status before read (0x%x)\n",
@@ -369,12 +426,12 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,
return -EIO;
}

- if (i+1 < length)
+ if (i + 1 < length)
octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB | TWSI_CTL_AAK);
+ TWSI_CTL_ENAB | TWSI_CTL_AAK);
else
octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL,
- TWSI_CTL_ENAB);
+ TWSI_CTL_ENAB);

result = octeon_i2c_wait(i2c);
if (result)
@@ -382,43 +439,41 @@ static int octeon_i2c_read(struct octeon_i2c *i2c, int target,

data[i] = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_DATA);
}
+ *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.
+ * 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.
+ * 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,
+static int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
int num)
{
- struct i2c_msg *pmsg;
- int i;
- int ret = 0;
struct octeon_i2c *i2c = i2c_get_adapdata(adap);
+ int i, ret = 0;

for (i = 0; ret == 0 && i < num; i++) {
- pmsg = &msgs[i];
+ struct i2c_msg *pmsg = &msgs[i];
+
dev_dbg(i2c->dev,
"Doing %s %d byte(s) to/from 0x%02x - %d of %d messages\n",
pmsg->flags & I2C_M_RD ? "read" : "write",
pmsg->len, pmsg->addr, i + 1, num);
if (pmsg->flags & I2C_M_RD)
ret = octeon_i2c_read(i2c, pmsg->addr, pmsg->buf,
- pmsg->len);
+ &pmsg->len);
else
ret = octeon_i2c_write(i2c, pmsg->addr, pmsg->buf,
- pmsg->len);
+ pmsg->len);
}
octeon_i2c_stop(i2c);

- return (ret != 0) ? ret : num;
+ return ret ? -EAGAIN : num;
}

static u32 octeon_i2c_functionality(struct i2c_adapter *adap)
@@ -435,13 +490,10 @@ static struct i2c_adapter octeon_i2c_ops = {
.owner = THIS_MODULE,
.name = "OCTEON adapter",
.algo = &octeon_i2c_algo,
- .timeout = HZ / 50,
};

-/**
- * octeon_i2c_setclock - Calculate and set clock divisors.
- */
-static int octeon_i2c_setclock(struct octeon_i2c *i2c)
+/* calculate and set clock divisors */
+static void octeon_i2c_setclock(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;
@@ -449,8 +501,7 @@ static int octeon_i2c_setclock(struct octeon_i2c *i2c)
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.
+ * with ds1337 RTCs, so we constrain it to larger values.
*/
for (mdiv_idx = 15; mdiv_idx >= 2 && delta_hz != 0; mdiv_idx--) {
/*
@@ -460,6 +511,7 @@ static int octeon_i2c_setclock(struct octeon_i2c *i2c)
tclk = i2c->twsi_freq * (mdiv_idx + 1) * 10;
tclk *= (1 << ndiv_idx);
thp_base = (i2c->sys_freq / (tclk * 2)) - 1;
+
for (inc = 0; inc <= 1; inc++) {
thp_idx = thp_base + inc;
if (thp_idx < 5 || thp_idx > 0xff)
@@ -480,36 +532,14 @@ static int octeon_i2c_setclock(struct octeon_i2c *i2c)
}
octeon_i2c_write_sw(i2c, SW_TWSI_OP_TWSI_CLK, thp);
octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CLKCTL, (mdiv << 3) | ndiv);
-
- return 0;
-}
-
-static int octeon_i2c_initlowlevel(struct octeon_i2c *i2c)
-{
- u8 status;
- int tries;
-
- /* disable high level controller, enable bus access */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_CTL, TWSI_CTL_ENAB);
-
- /* reset controller */
- octeon_i2c_write_sw(i2c, SW_TWSI_EOP_TWSI_RST, 0);
-
- for (tries = 10; tries; tries--) {
- udelay(1);
- status = octeon_i2c_read_sw(i2c, SW_TWSI_EOP_TWSI_STAT);
- if (status == STAT_IDLE)
- return 0;
- }
- dev_err(i2c->dev, "%s: TWSI_RST failed! (0x%x)\n", __func__, status);
- return -EIO;
}

static int octeon_i2c_probe(struct platform_device *pdev)
{
+ struct device_node *node = pdev->dev.of_node;
int irq, result = 0;
- struct octeon_i2c *i2c;
struct resource *res_mem;
+ struct octeon_i2c *i2c;

/* All adaptors have an irq. */
irq = platform_get_irq(pdev, 0);
@@ -518,7 +548,6 @@ static int octeon_i2c_probe(struct platform_device *pdev)

i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c) {
- dev_err(&pdev->dev, "kzalloc failed\n");
result = -ENOMEM;
goto out;
}
@@ -531,18 +560,14 @@ static int octeon_i2c_probe(struct platform_device *pdev)
result = -ENXIO;
goto out;
}
- i2c->twsi_phys = res_mem->start;
- i2c->regsize = resource_size(res_mem);

/*
* "clock-rate" is a legacy binding, the official binding is
* "clock-frequency". Try the official one first and then
* fall back if it doesn't exist.
*/
- if (of_property_read_u32(pdev->dev.of_node,
- "clock-frequency", &i2c->twsi_freq) &&
- of_property_read_u32(pdev->dev.of_node,
- "clock-rate", &i2c->twsi_freq)) {
+ if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) &&
+ of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) {
dev_err(i2c->dev,
"no I2C 'clock-rate' or 'clock-frequency' property\n");
result = -ENXIO;
@@ -551,15 +576,15 @@ static int octeon_i2c_probe(struct platform_device *pdev)

i2c->sys_freq = octeon_get_io_clock_rate();

- if (!devm_request_mem_region(&pdev->dev, i2c->twsi_phys, i2c->regsize,
- res_mem->name)) {
+ if (!devm_request_mem_region(&pdev->dev, res_mem->start,
+ resource_size(res_mem), res_mem->name)) {
dev_err(i2c->dev, "request_mem_region failed\n");
goto out;
}
- i2c->twsi_base = devm_ioremap(&pdev->dev, i2c->twsi_phys, i2c->regsize);

+ i2c->twsi_base = devm_ioremap(&pdev->dev, res_mem->start,
+ resource_size(res_mem));
init_waitqueue_head(&i2c->queue);
-
i2c->irq = irq;

result = devm_request_irq(&pdev->dev, i2c->irq,
@@ -575,15 +600,12 @@ static int octeon_i2c_probe(struct platform_device *pdev)
goto out;
}

- result = octeon_i2c_setclock(i2c);
- if (result) {
- dev_err(i2c->dev, "clock init failed\n");
- goto out;
- }
+ octeon_i2c_setclock(i2c);

i2c->adap = octeon_i2c_ops;
+ i2c->adap.timeout = msecs_to_jiffies(50);
i2c->adap.dev.parent = &pdev->dev;
- i2c->adap.dev.of_node = pdev->dev.of_node;
+ i2c->adap.dev.of_node = node;
i2c_set_adapdata(&i2c->adap, i2c);
platform_set_drvdata(pdev, i2c);

@@ -592,8 +614,7 @@ static int octeon_i2c_probe(struct platform_device *pdev)
dev_err(i2c->dev, "failed to add adapter\n");
goto out;
}
- dev_info(i2c->dev, "version %s\n", DRV_VERSION);
-
+ dev_info(i2c->dev, "probed\n");
return 0;

out:
@@ -608,10 +629,8 @@ static int octeon_i2c_remove(struct platform_device *pdev)
return 0;
};

-static struct of_device_id octeon_i2c_match[] = {
- {
- .compatible = "cavium,octeon-3860-twsi",
- },
+static const struct of_device_id octeon_i2c_match[] = {
+ { .compatible = "cavium,octeon-3860-twsi", },
{},
};
MODULE_DEVICE_TABLE(of, octeon_i2c_match);
@@ -630,4 +649,3 @@ module_platform_driver(octeon_i2c_driver);
MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@xxxxxxx>");
MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
MODULE_LICENSE("GPL");
-MODULE_VERSION(DRV_VERSION);
--
1.9.1