static int i2c_fsl_start(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
void __iomem *base = i2c_fsl->base;
unsigned int temp = 0;
int result;
writeb(i2c_fsl->ifdr, base + FSL_I2C_IFDR);
if (i2c_fsl->dfsrr != -1)
writeb(i2c_fsl->dfsrr, base + FSL_I2C_DFSRR);
/* Enable I2C controller */
writeb(0, base + FSL_I2C_I2SR);
writeb(I2CR_IEN, base + FSL_I2C_I2CR);
/* Wait controller to be stable */
udelay(100);
/* Start I2C transaction */
temp = readb(base + FSL_I2C_I2CR);
temp |= I2CR_MSTA;
writeb(temp, base + FSL_I2C_I2CR);
result = i2c_fsl_bus_busy(adapter, 1);
if (result)
return result;
i2c_fsl->stopped = 0;
temp |= I2CR_MTX | I2CR_TXAK;
writeb(temp, base + FSL_I2C_I2CR);
return result;
}
static int i2c_fsl_xfer(struct i2c_adapter *adapter,
struct i2c_msg *msgs, int num)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
void __iomem *base = i2c_fsl->base;
unsigned int i, temp;
int result;
/* Start I2C transfer */
for (i = 0; i < 3; i++) {
result = i2c_fsl_start(adapter);
if (!result)
break;
if (result == -EAGAIN)
continue;
return result;
}
/* read/write data */
for (i = 0; i < num; i++) {
if (i && !(msgs[i].flags & I2C_M_DATA_ONLY)) {
temp = readb(base + FSL_I2C_I2CR);
temp |= I2CR_RSTA;
writeb(temp, base + FSL_I2C_I2CR);
result = i2c_fsl_bus_busy(adapter, 1);
if (result)
goto fail0;
}
i2c_fsl_dump_reg(adapter);
/* write/read data */
if (msgs[i].flags & I2C_M_RD)
result = i2c_fsl_read(adapter, &msgs[i]);
else
result = i2c_fsl_write(adapter, &msgs[i]);
if (result)
goto fail0;
}
fail0:
/* Stop I2C transfer */
i2c_fsl_stop(adapter);
return (result < 0) ? result : num;
}
static int i2c_fsl_acked(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
uint64_t start;
start = get_time_ns();
while (1) {
unsigned int reg = fsl_i2c_read_reg(i2c_fsl, FSL_I2C_I2SR);
if (!(reg & I2SR_RXAK))
break;
if (is_timeout(start, MSECOND)) {
dev_dbg(&adapter->dev, "<%s> No ACK\n", __func__);
return -EIO;
}
}
return 0;
}
static int i2c_fsl_start(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
unsigned int temp = 0;
int result;
fsl_i2c_write_reg(i2c_fsl->ifdr, i2c_fsl, FSL_I2C_IFDR);
#ifdef CONFIG_PPC
if (i2c_fsl->dfsrr != -1)
fsl_i2c_write_reg(i2c_fsl->dfsrr, i2c_fsl, FSL_I2C_DFSRR);
#endif
/* Enable I2C controller */
fsl_i2c_write_reg(i2c_fsl->hwdata->i2sr_clr_opcode,
i2c_fsl, FSL_I2C_I2SR);
fsl_i2c_write_reg(i2c_fsl->hwdata->i2cr_ien_opcode,
i2c_fsl, FSL_I2C_I2CR);
/* Wait controller to be stable */
udelay(100);
/* Start I2C transaction */
temp = fsl_i2c_read_reg(i2c_fsl, FSL_I2C_I2CR);
temp |= I2CR_MSTA;
fsl_i2c_write_reg(temp, i2c_fsl, FSL_I2C_I2CR);
result = i2c_fsl_bus_busy(adapter, 1);
if (result) {
result = i2c_recover_bus(&i2c_fsl->adapter);
if (result)
return result;
return -EAGAIN;
}
i2c_fsl->stopped = 0;
temp |= I2CR_MTX | I2CR_TXAK;
fsl_i2c_write_reg(temp, i2c_fsl, FSL_I2C_I2CR);
return result;
}
static int i2c_fsl_trx_complete(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
void __iomem *base = i2c_fsl->base;
uint64_t start;
start = get_time_ns();
while (1) {
unsigned int reg = readb(base + FSL_I2C_I2SR);
if (reg & I2SR_IIF)
break;
if (is_timeout(start, 100 * MSECOND)) {
dev_err(&adapter->dev, "<%s> TXR timeout\n", __func__);
return -EIO;
}
}
writeb(0, base + FSL_I2C_I2SR);
return 0;
}
static void i2c_fsl_dump_reg(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
u32 reg_cr, reg_sr;
reg_cr = readb(i2c_fsl->base + FSL_I2C_I2CR);
reg_sr = readb(i2c_fsl->base + FSL_I2C_I2SR);
dev_dbg(adapter->dev, "CONTROL:\t"
"IEN =%d, IIEN=%d, MSTA=%d, MTX =%d, TXAK=%d, RSTA=%d\n",
(reg_cr & I2CR_IEN ? 1 : 0), (reg_cr & I2CR_IIEN ? 1 : 0),
(reg_cr & I2CR_MSTA ? 1 : 0), (reg_cr & I2CR_MTX ? 1 : 0),
(reg_cr & I2CR_TXAK ? 1 : 0), (reg_cr & I2CR_RSTA ? 1 : 0));
dev_dbg(adapter->dev, "STATUS:\t"
"ICF =%d, IAAS=%d, IB =%d, IAL =%d, SRW =%d, IIF =%d, RXAK=%d\n",
(reg_sr & I2SR_ICF ? 1 : 0), (reg_sr & I2SR_IAAS ? 1 : 0),
(reg_sr & I2SR_IBB ? 1 : 0), (reg_sr & I2SR_IAL ? 1 : 0),
(reg_sr & I2SR_SRW ? 1 : 0), (reg_sr & I2SR_IIF ? 1 : 0),
(reg_sr & I2SR_RXAK ? 1 : 0));
}
static int i2c_fsl_trx_complete(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
uint64_t start;
start = get_time_ns();
while (1) {
unsigned int reg = fsl_i2c_read_reg(i2c_fsl, FSL_I2C_I2SR);
if (reg & I2SR_IIF)
break;
if (is_timeout(start, 100 * MSECOND)) {
dev_err(&adapter->dev, "<%s> TXR timeout\n", __func__);
return -EIO;
}
}
fsl_i2c_write_reg(i2c_fsl->hwdata->i2sr_clr_opcode,
i2c_fsl, FSL_I2C_I2SR);
return 0;
}
static int i2c_fsl_write(struct i2c_adapter *adapter, struct i2c_msg *msgs)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
void __iomem *base = i2c_fsl->base;
int i, result;
if ( !(msgs->flags & I2C_M_DATA_ONLY) ) {
dev_dbg(&adapter->dev,
"<%s> write slave address: addr=0x%02x\n",
__func__, msgs->addr << 1);
/* write slave address */
writeb(msgs->addr << 1, base + FSL_I2C_I2DR);
result = i2c_fsl_trx_complete(adapter);
if (result)
return result;
result = i2c_fsl_acked(adapter);
if (result)
return result;
}
/* write data */
for (i = 0; i < msgs->len; i++) {
dev_dbg(&adapter->dev,
"<%s> write byte: B%d=0x%02X\n",
__func__, i, msgs->buf[i]);
writeb(msgs->buf[i], base + FSL_I2C_I2DR);
result = i2c_fsl_trx_complete(adapter);
if (result)
return result;
result = i2c_fsl_acked(adapter);
if (result)
return result;
}
return 0;
}
static int i2c_fsl_bus_busy(struct i2c_adapter *adapter, int for_busy)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
uint64_t start;
unsigned int temp;
start = get_time_ns();
while (1) {
temp = fsl_i2c_read_reg(i2c_fsl, FSL_I2C_I2SR);
if (for_busy && (temp & I2SR_IBB))
break;
if (!for_busy && !(temp & I2SR_IBB))
break;
if (is_timeout(start, 500 * MSECOND)) {
dev_err(&adapter->dev,
"<%s> timeout waiting for I2C bus %s\n",
__func__,for_busy ? "busy" : "not busy");
return -EIO;
}
}
return 0;
}
static void i2c_fsl_stop(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
void __iomem *base = i2c_fsl->base;
unsigned int temp = 0;
if (!i2c_fsl->stopped) {
/* Stop I2C transaction */
temp = readb(base + FSL_I2C_I2CR);
temp &= ~(I2CR_MSTA | I2CR_MTX);
writeb(temp, base + FSL_I2C_I2CR);
/* wait for the stop condition to be send, otherwise the i2c
* controller is disabled before the STOP is sent completely */
i2c_fsl->stopped = i2c_fsl_bus_busy(adapter, 0) ? 0 : 1;
}
if (!i2c_fsl->stopped) {
i2c_fsl_bus_busy(adapter, 0);
i2c_fsl->stopped = 1;
}
/* Disable I2C controller, and force our state to stopped */
writeb(0, base + FSL_I2C_I2CR);
}
static void i2c_fsl_stop(struct i2c_adapter *adapter)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
unsigned int temp = 0;
if (!i2c_fsl->stopped) {
/* Stop I2C transaction */
temp = fsl_i2c_read_reg(i2c_fsl, FSL_I2C_I2CR);
temp &= ~(I2CR_MSTA | I2CR_MTX);
fsl_i2c_write_reg(temp, i2c_fsl, FSL_I2C_I2CR);
/* wait for the stop condition to be send, otherwise the i2c
* controller is disabled before the STOP is sent completely */
i2c_fsl->stopped = i2c_fsl_bus_busy(adapter, 0) ? 0 : 1;
}
if (!i2c_fsl->stopped) {
i2c_fsl_bus_busy(adapter, 0);
i2c_fsl->stopped = 1;
}
/* Disable I2C controller, and force our state to stopped */
temp = i2c_fsl->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
fsl_i2c_write_reg(temp, i2c_fsl, FSL_I2C_I2CR);
}
static int i2c_fsl_read(struct i2c_adapter *adapter, struct i2c_msg *msgs)
{
struct fsl_i2c_struct *i2c_fsl = to_fsl_i2c_struct(adapter);
void __iomem *base = i2c_fsl->base;
int i, result;
unsigned int temp;
/* clear IIF */
writeb(0x0, base + FSL_I2C_I2SR);
if ( !(msgs->flags & I2C_M_DATA_ONLY) ) {
dev_dbg(&adapter->dev,
"<%s> write slave address: addr=0x%02x\n",
__func__, (msgs->addr << 1) | 0x01);
/* write slave address */
writeb((msgs->addr << 1) | 0x01, base + FSL_I2C_I2DR);
result = i2c_fsl_trx_complete(adapter);
if (result)
return result;
result = i2c_fsl_acked(adapter);
if (result)
return result;
}
/* setup bus to read data */
temp = readb(base + FSL_I2C_I2CR);
temp &= ~I2CR_MTX;
if (msgs->len - 1)
temp &= ~I2CR_TXAK;
writeb(temp, base + FSL_I2C_I2CR);
readb(base + FSL_I2C_I2DR); /* dummy read */
/* read data */
for (i = 0; i < msgs->len; i++) {
result = i2c_fsl_trx_complete(adapter);
if (result)
return result;
if (i == (msgs->len - 1)) {
/*
* It must generate STOP before read I2DR to prevent
* controller from generating another clock cycle
*/
temp = readb(base + FSL_I2C_I2CR);
temp &= ~(I2CR_MSTA | I2CR_MTX);
writeb(temp, base + FSL_I2C_I2CR);
/*
* adding this delay helps on low bitrates
*/
udelay(i2c_fsl->disable_delay);
i2c_fsl_bus_busy(adapter, 0);
i2c_fsl->stopped = 1;
} else if (i == (msgs->len - 2)) {
temp = readb(base + FSL_I2C_I2CR);
temp |= I2CR_TXAK;
writeb(temp, base + FSL_I2C_I2CR);
}
msgs->buf[i] = readb(base + FSL_I2C_I2DR);
dev_dbg(&adapter->dev, "<%s> read byte: B%d=0x%02X\n",
__func__, i, msgs->buf[i]);
}
return 0;
}
