diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-eg20t.c')
-rw-r--r-- | drivers/i2c/busses/i2c-eg20t.c | 270 |
1 files changed, 196 insertions, 74 deletions
diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c index ce1a32b71e47..8cebef49aeac 100644 --- a/drivers/i2c/busses/i2c-eg20t.c +++ b/drivers/i2c/busses/i2c-eg20t.c @@ -64,6 +64,7 @@ #define TEN_BIT_ADDR_DEFAULT 0xF000 #define TEN_BIT_ADDR_MASK 0xF0 #define PCH_START 0x0020 +#define PCH_RESTART 0x0004 #define PCH_ESR_START 0x0001 #define PCH_BUFF_START 0x1 #define PCH_REPSTART 0x0004 @@ -273,23 +274,24 @@ static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap, s32 timeout) { void __iomem *p = adap->pch_base_address; + ktime_t ns_val; + + if ((ioread32(p + PCH_I2CSR) & I2CMBB_BIT) == 0) + return 0; /* MAX timeout value is timeout*1000*1000nsec */ - ktime_t ns_val = ktime_add_ns(ktime_get(), timeout*1000*1000); + ns_val = ktime_add_ns(ktime_get(), timeout*1000*1000); do { - if ((ioread32(p + PCH_I2CSR) & I2CMBB_BIT) == 0) - break; msleep(20); + if ((ioread32(p + PCH_I2CSR) & I2CMBB_BIT) == 0) + return 0; } while (ktime_lt(ktime_get(), ns_val)); pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR)); + pch_err(adap, "%s: Timeout Error.return%d\n", __func__, -ETIME); + pch_i2c_init(adap); - if (timeout == 0) { - pch_err(adap, "%s: Timeout Error.return%d\n", __func__, -ETIME); - return -ETIME; - } - - return 0; + return -ETIME; } /** @@ -311,21 +313,19 @@ static void pch_i2c_start(struct i2c_algo_pch_data *adap) */ static s32 pch_i2c_wait_for_xfer_complete(struct i2c_algo_pch_data *adap) { - s32 ret; + long ret; ret = wait_event_timeout(pch_event, (adap->pch_event_flag != 0), msecs_to_jiffies(50)); - if (ret < 0) { - pch_err(adap, "timeout: %x\n", adap->pch_event_flag); - return ret; - } if (ret == 0) { pch_err(adap, "timeout: %x\n", adap->pch_event_flag); + adap->pch_event_flag = 0; return -ETIMEDOUT; } if (adap->pch_event_flag & I2C_ERROR_MASK) { pch_err(adap, "error bits set: %x\n", adap->pch_event_flag); + adap->pch_event_flag = 0; return -EIO; } @@ -394,6 +394,7 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap, u32 addr_2_msb; u32 addr_8_lsb; s32 wrcount; + s32 rtn; void __iomem *p = adap->pch_base_address; length = msgs->len; @@ -412,15 +413,29 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap, } if (msgs->flags & I2C_M_TEN) { - addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7); + addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06; iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); if (first) pch_i2c_start(adap); - if (pch_i2c_wait_for_xfer_complete(adap) == 0 && - pch_i2c_getack(adap) == 0) { + + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave address" + "setting\n"); + return -EIO; + } addr_8_lsb = (addr & I2C_ADDR_MSK); iowrite32(addr_8_lsb, p + PCH_I2CDR); - } else { + } else if (rtn == -EIO) { /* Arbitration Lost */ + pch_err(adap, "Lost Arbitration\n"); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMAL_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMIF_BIT); + pch_i2c_init(adap); + return -EAGAIN; + } else { /* wait-event timeout */ pch_i2c_stop(adap); return -ETIME; } @@ -431,30 +446,51 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap, pch_i2c_start(adap); } - if ((pch_i2c_wait_for_xfer_complete(adap) == 0) && - (pch_i2c_getack(adap) == 0)) { - for (wrcount = 0; wrcount < length; ++wrcount) { - /* write buffer value to I2C data register */ - iowrite32(buf[wrcount], p + PCH_I2CDR); - pch_dbg(adap, "writing %x to Data register\n", - buf[wrcount]); + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave address" + "setting\n"); + return -EIO; + } + } else if (rtn == -EIO) { /* Arbitration Lost */ + pch_err(adap, "Lost Arbitration\n"); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT); + pch_i2c_init(adap); + return -EAGAIN; + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; + } - if (pch_i2c_wait_for_xfer_complete(adap) != 0) - return -ETIME; + for (wrcount = 0; wrcount < length; ++wrcount) { + /* write buffer value to I2C data register */ + iowrite32(buf[wrcount], p + PCH_I2CDR); + pch_dbg(adap, "writing %x to Data register\n", buf[wrcount]); - if (pch_i2c_getack(adap)) + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave address" + "setting\n"); return -EIO; + } + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMCF_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMIF_BIT); + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; } + } - /* check if this is the last message */ - if (last) - pch_i2c_stop(adap); - else - pch_i2c_repstart(adap); - } else { + /* check if this is the last message */ + if (last) pch_i2c_stop(adap); - return -EIO; - } + else + pch_i2c_repstart(adap); pch_dbg(adap, "return=%d\n", wrcount); @@ -484,6 +520,19 @@ static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap) } /** + * pch_i2c_restart() - Generate I2C restart condition in normal mode. + * @adap: Pointer to struct i2c_algo_pch_data. + * + * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA. + */ +static void pch_i2c_restart(struct i2c_algo_pch_data *adap) +{ + void __iomem *p = adap->pch_base_address; + pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL)); + pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_RESTART); +} + +/** * pch_i2c_readbytes() - read data from I2C bus in normal mode. * @i2c_adap: Pointer to the struct i2c_adapter. * @msgs: Pointer to i2c_msg structure. @@ -500,7 +549,9 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, u32 length; u32 addr; u32 addr_2_msb; + u32 addr_8_lsb; void __iomem *p = adap->pch_base_address; + s32 rtn; length = msgs->len; buf = msgs->buf; @@ -515,9 +566,55 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, } if (msgs->flags & I2C_M_TEN) { - addr_2_msb = (((addr & I2C_MSB_2B_MSK) >> 7) | (I2C_RD)); + addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7); iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR); + if (first) + pch_i2c_start(adap); + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave address" + "setting\n"); + return -EIO; + } + addr_8_lsb = (addr & I2C_ADDR_MSK); + iowrite32(addr_8_lsb, p + PCH_I2CDR); + } else if (rtn == -EIO) { /* Arbitration Lost */ + pch_err(adap, "Lost Arbitration\n"); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMAL_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMIF_BIT); + pch_i2c_init(adap); + return -EAGAIN; + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; + } + pch_i2c_restart(adap); + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave address" + "setting\n"); + return -EIO; + } + addr_2_msb |= I2C_RD; + iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, + p + PCH_I2CDR); + } else if (rtn == -EIO) { /* Arbitration Lost */ + pch_err(adap, "Lost Arbitration\n"); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMAL_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, + I2CMIF_BIT); + pch_i2c_init(adap); + return -EAGAIN; + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; + } } else { /* 7 address bits + R/W bit */ addr = (((addr) << 1) | (I2C_RD)); @@ -528,56 +625,81 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, if (first) pch_i2c_start(adap); - if ((pch_i2c_wait_for_xfer_complete(adap) == 0) && - (pch_i2c_getack(adap) == 0)) { - pch_dbg(adap, "return %d\n", 0); + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave address" + "setting\n"); + return -EIO; + } + } else if (rtn == -EIO) { /* Arbitration Lost */ + pch_err(adap, "Lost Arbitration\n"); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT); + pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT); + pch_i2c_init(adap); + return -EAGAIN; + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; + } - if (length == 0) { - pch_i2c_stop(adap); - ioread32(p + PCH_I2CDR); /* Dummy read needs */ + if (length == 0) { + pch_i2c_stop(adap); + ioread32(p + PCH_I2CDR); /* Dummy read needs */ - count = length; - } else { - int read_index; - int loop; - pch_i2c_sendack(adap); + count = length; + } else { + int read_index; + int loop; + pch_i2c_sendack(adap); - /* Dummy read */ - for (loop = 1, read_index = 0; loop < length; loop++) { - buf[read_index] = ioread32(p + PCH_I2CDR); + /* Dummy read */ + for (loop = 1, read_index = 0; loop < length; loop++) { + buf[read_index] = ioread32(p + PCH_I2CDR); - if (loop != 1) - read_index++; + if (loop != 1) + read_index++; - if (pch_i2c_wait_for_xfer_complete(adap) != 0) { - pch_i2c_stop(adap); - return -ETIME; + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave" + "address setting\n"); + return -EIO; } - } /* end for */ + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; + } - pch_i2c_sendnack(adap); + } /* end for */ - buf[read_index] = ioread32(p + PCH_I2CDR); + pch_i2c_sendnack(adap); - if (length != 1) - read_index++; + buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */ - if (pch_i2c_wait_for_xfer_complete(adap) == 0) { - if (last) - pch_i2c_stop(adap); - else - pch_i2c_repstart(adap); + if (length != 1) + read_index++; - buf[read_index++] = ioread32(p + PCH_I2CDR); - count = read_index; - } else { - count = -ETIME; + rtn = pch_i2c_wait_for_xfer_complete(adap); + if (rtn == 0) { + if (pch_i2c_getack(adap)) { + pch_dbg(adap, "Receive NACK for slave" + "address setting\n"); + return -EIO; } - + } else { /* wait-event timeout */ + pch_i2c_stop(adap); + return -ETIME; } - } else { - count = -ETIME; - pch_i2c_stop(adap); + + if (last) + pch_i2c_stop(adap); + else + pch_i2c_repstart(adap); + + buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */ + count = read_index; } return count; |