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linux/drivers/i2c/busses/i2c-bfin-twi.c
Michael Hennerich 958585f58f i2c: Blackfin I2C Driver: Functional power management support 
PM_SUSPEND_MEM: Blackfin does not maintain register state through
Hibernate. Save and restore peripheral base initialization during
PM transitions.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-28 12:41:03 +01:00

758 lines
19 KiB
C
Raw Blame History

/*
* Blackfin On-Chip Two Wire Interface Driver
*
* Copyright 2005-2007 Analog Devices Inc.
*
* Enter bugs at http://blackfin.uclinux.org/
*
* Licensed under the GPL-2 or later.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/mm.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <asm/blackfin.h>
#include <asm/portmux.h>
#include <asm/irq.h>
#define POLL_TIMEOUT (2 * HZ)
/* SMBus mode*/
#define TWI_I2C_MODE_STANDARD 1
#define TWI_I2C_MODE_STANDARDSUB 2
#define TWI_I2C_MODE_COMBINED 3
#define TWI_I2C_MODE_REPEAT 4
struct bfin_twi_iface {
int irq;
spinlock_t lock;
char read_write;
u8 command;
u8 *transPtr;
int readNum;
int writeNum;
int cur_mode;
int manual_stop;
int result;
int timeout_count;
struct timer_list timeout_timer;
struct i2c_adapter adap;
struct completion complete;
struct i2c_msg *pmsg;
int msg_num;
int cur_msg;
u16 saved_clkdiv;
u16 saved_control;
void __iomem *regs_base;
};
#define DEFINE_TWI_REG(reg, off) \
static inline u16 read_##reg(struct bfin_twi_iface *iface) \
{ return bfin_read16(iface->regs_base + (off)); } \
static inline void write_##reg(struct bfin_twi_iface *iface, u16 v) \
{ bfin_write16(iface->regs_base + (off), v); }
DEFINE_TWI_REG(CLKDIV, 0x00)
DEFINE_TWI_REG(CONTROL, 0x04)
DEFINE_TWI_REG(SLAVE_CTL, 0x08)
DEFINE_TWI_REG(SLAVE_STAT, 0x0C)
DEFINE_TWI_REG(SLAVE_ADDR, 0x10)
DEFINE_TWI_REG(MASTER_CTL, 0x14)
DEFINE_TWI_REG(MASTER_STAT, 0x18)
DEFINE_TWI_REG(MASTER_ADDR, 0x1C)
DEFINE_TWI_REG(INT_STAT, 0x20)
DEFINE_TWI_REG(INT_MASK, 0x24)
DEFINE_TWI_REG(FIFO_CTL, 0x28)
DEFINE_TWI_REG(FIFO_STAT, 0x2C)
DEFINE_TWI_REG(XMT_DATA8, 0x80)
DEFINE_TWI_REG(XMT_DATA16, 0x84)
DEFINE_TWI_REG(RCV_DATA8, 0x88)
DEFINE_TWI_REG(RCV_DATA16, 0x8C)
static const u16 pin_req[2][3] = {
{P_TWI0_SCL, P_TWI0_SDA, 0},
{P_TWI1_SCL, P_TWI1_SDA, 0},
};
static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
{
unsigned short twi_int_status = read_INT_STAT(iface);
unsigned short mast_stat = read_MASTER_STAT(iface);
if (twi_int_status & XMTSERV) {
/* Transmit next data */
if (iface->writeNum > 0) {
write_XMT_DATA8(iface, *(iface->transPtr++));
iface->writeNum--;
}
/* start receive immediately after complete sending in
* combine mode.
*/
else if (iface->cur_mode == TWI_I2C_MODE_COMBINED)
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | MDIR | RSTART);
else if (iface->manual_stop)
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | STOP);
else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
iface->cur_msg+1 < iface->msg_num)
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | RSTART);
SSYNC();
/* Clear status */
write_INT_STAT(iface, XMTSERV);
SSYNC();
}
if (twi_int_status & RCVSERV) {
if (iface->readNum > 0) {
/* Receive next data */
*(iface->transPtr) = read_RCV_DATA8(iface);
if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
/* Change combine mode into sub mode after
* read first data.
*/
iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
/* Get read number from first byte in block
* combine mode.
*/
if (iface->readNum == 1 && iface->manual_stop)
iface->readNum = *iface->transPtr + 1;
}
iface->transPtr++;
iface->readNum--;
} else if (iface->manual_stop) {
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | STOP);
SSYNC();
} else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
iface->cur_msg+1 < iface->msg_num) {
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | RSTART);
SSYNC();
}
/* Clear interrupt source */
write_INT_STAT(iface, RCVSERV);
SSYNC();
}
if (twi_int_status & MERR) {
write_INT_STAT(iface, MERR);
write_INT_MASK(iface, 0);
write_MASTER_STAT(iface, 0x3e);
write_MASTER_CTL(iface, 0);
SSYNC();
iface->result = -EIO;
/* if both err and complete int stats are set, return proper
* results.
*/
if (twi_int_status & MCOMP) {
write_INT_STAT(iface, MCOMP);
write_INT_MASK(iface, 0);
write_MASTER_CTL(iface, 0);
SSYNC();
/* If it is a quick transfer, only address bug no data,
* not an err, return 1.
*/
if (iface->writeNum == 0 && (mast_stat & BUFRDERR))
iface->result = 1;
/* If address not acknowledged return -1,
* else return 0.
*/
else if (!(mast_stat & ANAK))
iface->result = 0;
}
complete(&iface->complete);
return;
}
if (twi_int_status & MCOMP) {
write_INT_STAT(iface, MCOMP);
SSYNC();
if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
if (iface->readNum == 0) {
/* set the read number to 1 and ask for manual
* stop in block combine mode
*/
iface->readNum = 1;
iface->manual_stop = 1;
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | (0xff << 6));
} else {
/* set the readd number in other
* combine mode.
*/
write_MASTER_CTL(iface,
(read_MASTER_CTL(iface) &
(~(0xff << 6))) |
(iface->readNum << 6));
}
/* remove restart bit and enable master receive */
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) & ~RSTART);
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) | MEN | MDIR);
SSYNC();
} else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
iface->cur_msg+1 < iface->msg_num) {
iface->cur_msg++;
iface->transPtr = iface->pmsg[iface->cur_msg].buf;
iface->writeNum = iface->readNum =
iface->pmsg[iface->cur_msg].len;
/* Set Transmit device address */
write_MASTER_ADDR(iface,
iface->pmsg[iface->cur_msg].addr);
if (iface->pmsg[iface->cur_msg].flags & I2C_M_RD)
iface->read_write = I2C_SMBUS_READ;
else {
iface->read_write = I2C_SMBUS_WRITE;
/* Transmit first data */
if (iface->writeNum > 0) {
write_XMT_DATA8(iface,
*(iface->transPtr++));
iface->writeNum--;
SSYNC();
}
}
if (iface->pmsg[iface->cur_msg].len <= 255)
write_MASTER_CTL(iface,
iface->pmsg[iface->cur_msg].len << 6);
else {
write_MASTER_CTL(iface, 0xff << 6);
iface->manual_stop = 1;
}
/* remove restart bit and enable master receive */
write_MASTER_CTL(iface,
read_MASTER_CTL(iface) & ~RSTART);
write_MASTER_CTL(iface, read_MASTER_CTL(iface) |
MEN | ((iface->read_write == I2C_SMBUS_READ) ?
MDIR : 0));
SSYNC();
} else {
iface->result = 1;
write_INT_MASK(iface, 0);
write_MASTER_CTL(iface, 0);
SSYNC();
complete(&iface->complete);
}
}
}
/* Interrupt handler */
static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id)
{
struct bfin_twi_iface *iface = dev_id;
unsigned long flags;
spin_lock_irqsave(&iface->lock, flags);
del_timer(&iface->timeout_timer);
bfin_twi_handle_interrupt(iface);
spin_unlock_irqrestore(&iface->lock, flags);
return IRQ_HANDLED;
}
static void bfin_twi_timeout(unsigned long data)
{
struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data;
unsigned long flags;
spin_lock_irqsave(&iface->lock, flags);
bfin_twi_handle_interrupt(iface);
if (iface->result == 0) {
iface->timeout_count--;
if (iface->timeout_count > 0) {
iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
add_timer(&iface->timeout_timer);
} else {
iface->result = -1;
complete(&iface->complete);
}
}
spin_unlock_irqrestore(&iface->lock, flags);
}
/*
* Generic i2c master transfer entrypoint
*/
static int bfin_twi_master_xfer(struct i2c_adapter *adap,
struct i2c_msg *msgs, int num)
{
struct bfin_twi_iface *iface = adap->algo_data;
struct i2c_msg *pmsg;
int rc = 0;
if (!(read_CONTROL(iface) & TWI_ENA))
return -ENXIO;
while (read_MASTER_STAT(iface) & BUSBUSY)
yield();
iface->pmsg = msgs;
iface->msg_num = num;
iface->cur_msg = 0;
pmsg = &msgs[0];
if (pmsg->flags & I2C_M_TEN) {
dev_err(&adap->dev, "10 bits addr not supported!\n");
return -EINVAL;
}
iface->cur_mode = TWI_I2C_MODE_REPEAT;
iface->manual_stop = 0;
iface->transPtr = pmsg->buf;
iface->writeNum = iface->readNum = pmsg->len;
iface->result = 0;
iface->timeout_count = 10;
init_completion(&(iface->complete));
/* Set Transmit device address */
write_MASTER_ADDR(iface, pmsg->addr);
/* FIFO Initiation. Data in FIFO should be
* discarded before start a new operation.
*/
write_FIFO_CTL(iface, 0x3);
SSYNC();
write_FIFO_CTL(iface, 0);
SSYNC();
if (pmsg->flags & I2C_M_RD)
iface->read_write = I2C_SMBUS_READ;
else {
iface->read_write = I2C_SMBUS_WRITE;
/* Transmit first data */
if (iface->writeNum > 0) {
write_XMT_DATA8(iface, *(iface->transPtr++));
iface->writeNum--;
SSYNC();
}
}
/* clear int stat */
write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
/* Interrupt mask . Enable XMT, RCV interrupt */
write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
SSYNC();
if (pmsg->len <= 255)
write_MASTER_CTL(iface, pmsg->len << 6);
else {
write_MASTER_CTL(iface, 0xff << 6);
iface->manual_stop = 1;
}
iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
add_timer(&iface->timeout_timer);
/* Master enable */
write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
SSYNC();
wait_for_completion(&iface->complete);
rc = iface->result;
if (rc == 1)
return num;
else
return rc;
}
/*
* SMBus type transfer entrypoint
*/
int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size, union i2c_smbus_data *data)
{
struct bfin_twi_iface *iface = adap->algo_data;
int rc = 0;
if (!(read_CONTROL(iface) & TWI_ENA))
return -ENXIO;
while (read_MASTER_STAT(iface) & BUSBUSY)
yield();
iface->writeNum = 0;
iface->readNum = 0;
/* Prepare datas & select mode */
switch (size) {
case I2C_SMBUS_QUICK:
iface->transPtr = NULL;
iface->cur_mode = TWI_I2C_MODE_STANDARD;
break;
case I2C_SMBUS_BYTE:
if (data == NULL)
iface->transPtr = NULL;
else {
if (read_write == I2C_SMBUS_READ)
iface->readNum = 1;
else
iface->writeNum = 1;
iface->transPtr = &data->byte;
}
iface->cur_mode = TWI_I2C_MODE_STANDARD;
break;
case I2C_SMBUS_BYTE_DATA:
if (read_write == I2C_SMBUS_READ) {
iface->readNum = 1;
iface->cur_mode = TWI_I2C_MODE_COMBINED;
} else {
iface->writeNum = 1;
iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
}
iface->transPtr = &data->byte;
break;
case I2C_SMBUS_WORD_DATA:
if (read_write == I2C_SMBUS_READ) {
iface->readNum = 2;
iface->cur_mode = TWI_I2C_MODE_COMBINED;
} else {
iface->writeNum = 2;
iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
}
iface->transPtr = (u8 *)&data->word;
break;
case I2C_SMBUS_PROC_CALL:
iface->writeNum = 2;
iface->readNum = 2;
iface->cur_mode = TWI_I2C_MODE_COMBINED;
iface->transPtr = (u8 *)&data->word;
break;
case I2C_SMBUS_BLOCK_DATA:
if (read_write == I2C_SMBUS_READ) {
iface->readNum = 0;
iface->cur_mode = TWI_I2C_MODE_COMBINED;
} else {
iface->writeNum = data->block[0] + 1;
iface->cur_mode = TWI_I2C_MODE_STANDARDSUB;
}
iface->transPtr = data->block;
break;
default:
return -1;
}
iface->result = 0;
iface->manual_stop = 0;
iface->read_write = read_write;
iface->command = command;
iface->timeout_count = 10;
init_completion(&(iface->complete));
/* FIFO Initiation. Data in FIFO should be discarded before
* start a new operation.
*/
write_FIFO_CTL(iface, 0x3);
SSYNC();
write_FIFO_CTL(iface, 0);
/* clear int stat */
write_INT_STAT(iface, MERR | MCOMP | XMTSERV | RCVSERV);
/* Set Transmit device address */
write_MASTER_ADDR(iface, addr);
SSYNC();
iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
add_timer(&iface->timeout_timer);
switch (iface->cur_mode) {
case TWI_I2C_MODE_STANDARDSUB:
write_XMT_DATA8(iface, iface->command);
write_INT_MASK(iface, MCOMP | MERR |
((iface->read_write == I2C_SMBUS_READ) ?
RCVSERV : XMTSERV));
SSYNC();
if (iface->writeNum + 1 <= 255)
write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
else {
write_MASTER_CTL(iface, 0xff << 6);
iface->manual_stop = 1;
}
/* Master enable */
write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
break;
case TWI_I2C_MODE_COMBINED:
write_XMT_DATA8(iface, iface->command);
write_INT_MASK(iface, MCOMP | MERR | RCVSERV | XMTSERV);
SSYNC();
if (iface->writeNum > 0)
write_MASTER_CTL(iface, (iface->writeNum + 1) << 6);
else
write_MASTER_CTL(iface, 0x1 << 6);
/* Master enable */
write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0));
break;
default:
write_MASTER_CTL(iface, 0);
if (size != I2C_SMBUS_QUICK) {
/* Don't access xmit data register when this is a
* read operation.
*/
if (iface->read_write != I2C_SMBUS_READ) {
if (iface->writeNum > 0) {
write_XMT_DATA8(iface,
*(iface->transPtr++));
if (iface->writeNum <= 255)
write_MASTER_CTL(iface,
iface->writeNum << 6);
else {
write_MASTER_CTL(iface,
0xff << 6);
iface->manual_stop = 1;
}
iface->writeNum--;
} else {
write_XMT_DATA8(iface, iface->command);
write_MASTER_CTL(iface, 1 << 6);
}
} else {
if (iface->readNum > 0 && iface->readNum <= 255)
write_MASTER_CTL(iface,
iface->readNum << 6);
else if (iface->readNum > 255) {
write_MASTER_CTL(iface, 0xff << 6);
iface->manual_stop = 1;
} else {
del_timer(&iface->timeout_timer);
break;
}
}
}
write_INT_MASK(iface, MCOMP | MERR |
((iface->read_write == I2C_SMBUS_READ) ?
RCVSERV : XMTSERV));
SSYNC();
/* Master enable */
write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
break;
}
SSYNC();
wait_for_completion(&iface->complete);
rc = (iface->result >= 0) ? 0 : -1;
return rc;
}
/*
* Return what the adapter supports
*/
static u32 bfin_twi_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL |
I2C_FUNC_I2C;
}
static struct i2c_algorithm bfin_twi_algorithm = {
.master_xfer = bfin_twi_master_xfer,
.smbus_xfer = bfin_twi_smbus_xfer,
.functionality = bfin_twi_functionality,
};
static int i2c_bfin_twi_suspend(struct platform_device *pdev, pm_message_t state)
{
struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
iface->saved_clkdiv = read_CLKDIV(iface);
iface->saved_control = read_CONTROL(iface);
free_irq(iface->irq, iface);
/* Disable TWI */
write_CONTROL(iface, iface->saved_control & ~TWI_ENA);
return 0;
}
static int i2c_bfin_twi_resume(struct platform_device *pdev)
{
struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
int rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
IRQF_DISABLED, pdev->name, iface);
if (rc) {
dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
return -ENODEV;
}
/* Resume TWI interface clock as specified */
write_CLKDIV(iface, iface->saved_clkdiv);
/* Resume TWI */
write_CONTROL(iface, iface->saved_control);
return 0;
}
static int i2c_bfin_twi_probe(struct platform_device *pdev)
{
struct bfin_twi_iface *iface;
struct i2c_adapter *p_adap;
struct resource *res;
int rc;
iface = kzalloc(sizeof(struct bfin_twi_iface), GFP_KERNEL);
if (!iface) {
dev_err(&pdev->dev, "Cannot allocate memory\n");
rc = -ENOMEM;
goto out_error_nomem;
}
spin_lock_init(&(iface->lock));
/* Find and map our resources */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "Cannot get IORESOURCE_MEM\n");
rc = -ENOENT;
goto out_error_get_res;
}
iface->regs_base = ioremap(res->start, res->end - res->start + 1);
if (iface->regs_base == NULL) {
dev_err(&pdev->dev, "Cannot map IO\n");
rc = -ENXIO;
goto out_error_ioremap;
}
iface->irq = platform_get_irq(pdev, 0);
if (iface->irq < 0) {
dev_err(&pdev->dev, "No IRQ specified\n");
rc = -ENOENT;
goto out_error_no_irq;
}
init_timer(&(iface->timeout_timer));
iface->timeout_timer.function = bfin_twi_timeout;
iface->timeout_timer.data = (unsigned long)iface;
p_adap = &iface->adap;
p_adap->id = I2C_HW_BLACKFIN;
p_adap->nr = pdev->id;
strlcpy(p_adap->name, pdev->name, sizeof(p_adap->name));
p_adap->algo = &bfin_twi_algorithm;
p_adap->algo_data = iface;
p_adap->class = I2C_CLASS_ALL;
p_adap->dev.parent = &pdev->dev;
rc = peripheral_request_list(pin_req[pdev->id], "i2c-bfin-twi");
if (rc) {
dev_err(&pdev->dev, "Can't setup pin mux!\n");
goto out_error_pin_mux;
}
rc = request_irq(iface->irq, bfin_twi_interrupt_entry,
IRQF_DISABLED, pdev->name, iface);
if (rc) {
dev_err(&pdev->dev, "Can't get IRQ %d !\n", iface->irq);
rc = -ENODEV;
goto out_error_req_irq;
}
/* Set TWI internal clock as 10MHz */
write_CONTROL(iface, ((get_sclk() / 1024 / 1024 + 5) / 10) & 0x7F);
/* Set Twi interface clock as specified */
write_CLKDIV(iface, ((5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ)
<< 8) | ((5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ)
& 0xFF));
/* Enable TWI */
write_CONTROL(iface, read_CONTROL(iface) | TWI_ENA);
SSYNC();
rc = i2c_add_numbered_adapter(p_adap);
if (rc < 0) {
dev_err(&pdev->dev, "Can't add i2c adapter!\n");
goto out_error_add_adapter;
}
platform_set_drvdata(pdev, iface);
dev_info(&pdev->dev, "Blackfin BF5xx on-chip I2C TWI Contoller, "
"regs_base@%p\n", iface->regs_base);
return 0;
out_error_add_adapter:
free_irq(iface->irq, iface);
out_error_req_irq:
out_error_no_irq:
peripheral_free_list(pin_req[pdev->id]);
out_error_pin_mux:
iounmap(iface->regs_base);
out_error_ioremap:
out_error_get_res:
kfree(iface);
out_error_nomem:
return rc;
}
static int i2c_bfin_twi_remove(struct platform_device *pdev)
{
struct bfin_twi_iface *iface = platform_get_drvdata(pdev);
platform_set_drvdata(pdev, NULL);
i2c_del_adapter(&(iface->adap));
free_irq(iface->irq, iface);
peripheral_free_list(pin_req[pdev->id]);
iounmap(iface->regs_base);
kfree(iface);
return 0;
}
static struct platform_driver i2c_bfin_twi_driver = {
.probe = i2c_bfin_twi_probe,
.remove = i2c_bfin_twi_remove,
.suspend = i2c_bfin_twi_suspend,
.resume = i2c_bfin_twi_resume,
.driver = {
.name = "i2c-bfin-twi",
.owner = THIS_MODULE,
},
};
static int __init i2c_bfin_twi_init(void)
{
return platform_driver_register(&i2c_bfin_twi_driver);
}
static void __exit i2c_bfin_twi_exit(void)
{
platform_driver_unregister(&i2c_bfin_twi_driver);
}
module_init(i2c_bfin_twi_init);
module_exit(i2c_bfin_twi_exit);
MODULE_AUTHOR("Bryan Wu, Sonic Zhang");
MODULE_DESCRIPTION("Blackfin BF5xx on-chip I2C TWI Contoller Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:i2c-bfin-twi");
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