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-rw-r--r--drivers/i2c/busses/i2c-i801.c116
1 files changed, 75 insertions, 41 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 611b571..d5e12a4 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -22,10 +22,10 @@
/*
SUPPORTED DEVICES PCI ID
- 82801AA 2413
- 82801AB 2423
- 82801BA 2443
- 82801CA/CAM 2483
+ 82801AA 2413
+ 82801AB 2423
+ 82801BA 2443
+ 82801CA/CAM 2483
82801DB 24C3 (HW PEC supported, 32 byte buffer not supported)
82801EB 24D3 (HW PEC supported, 32 byte buffer not supported)
6300ESB 25A4
@@ -74,6 +74,13 @@
#define SMBHSTCFG_SMB_SMI_EN 2
#define SMBHSTCFG_I2C_EN 4
+/* Auxillary control register bits, ICH4+ only */
+#define SMBAUXCTL_CRC 1
+#define SMBAUXCTL_E32B 2
+
+/* kill bit for SMBHSTCNT */
+#define SMBHSTCNT_KILL 2
+
/* Other settings */
#define MAX_TIMEOUT 100
#define ENABLE_INT9 0 /* set to 0x01 to enable - untested */
@@ -91,10 +98,15 @@
#define I801_START 0x40
#define I801_PEC_EN 0x80 /* ICH4 only */
-
-static int i801_transaction(void);
-static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
- int command, int hwpec);
+/* I801 Hosts Status register bits */
+#define SMBHSTSTS_BYTE_DONE 0x80
+#define SMBHSTSTS_INUSE_STS 0x40
+#define SMBHSTSTS_SMBALERT_STS 0x20
+#define SMBHSTSTS_FAILED 0x10
+#define SMBHSTSTS_BUS_ERR 0x08
+#define SMBHSTSTS_DEV_ERR 0x04
+#define SMBHSTSTS_INTR 0x02
+#define SMBHSTSTS_HOST_BUSY 0x01
static unsigned long i801_smba;
static unsigned char i801_original_hstcfg;
@@ -133,27 +145,32 @@ static int i801_transaction(void)
do {
msleep(1);
temp = inb_p(SMBHSTSTS);
- } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
+ } while ((temp & SMBHSTSTS_HOST_BUSY) && (timeout++ < MAX_TIMEOUT));
/* If the SMBus is still busy, we give up */
if (timeout >= MAX_TIMEOUT) {
dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
result = -1;
+ /* try to stop the current command */
+ dev_dbg(&I801_dev->dev, "Terminating the current operation\n");
+ outb_p(inb_p(SMBHSTCNT) | SMBHSTCNT_KILL, SMBHSTCNT);
+ msleep(1);
+ outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL), SMBHSTCNT);
}
- if (temp & 0x10) {
+ if (temp & SMBHSTSTS_FAILED) {
result = -1;
dev_dbg(&I801_dev->dev, "Error: Failed bus transaction\n");
}
- if (temp & 0x08) {
+ if (temp & SMBHSTSTS_BUS_ERR) {
result = -1;
dev_err(&I801_dev->dev, "Bus collision! SMBus may be locked "
"until next hard reset. (sorry!)\n");
/* Clock stops and slave is stuck in mid-transmission */
}
- if (temp & 0x04) {
+ if (temp & SMBHSTSTS_DEV_ERR) {
result = -1;
dev_dbg(&I801_dev->dev, "Error: no response!\n");
}
@@ -172,6 +189,24 @@ static int i801_transaction(void)
return result;
}
+/* wait for INTR bit as advised by Intel */
+static void i801_wait_hwpec(void)
+{
+ int timeout = 0;
+ int temp;
+
+ do {
+ msleep(1);
+ temp = inb_p(SMBHSTSTS);
+ } while ((!(temp & SMBHSTSTS_INTR))
+ && (timeout++ < MAX_TIMEOUT));
+
+ if (timeout >= MAX_TIMEOUT) {
+ dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
+ }
+ outb_p(temp, SMBHSTSTS);
+}
+
/* All-inclusive block transaction function */
static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
int command, int hwpec)
@@ -227,13 +262,13 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
/* Make sure the SMBus host is ready to start transmitting */
temp = inb_p(SMBHSTSTS);
if (i == 1) {
- /* Erronenous conditions before transaction:
+ /* Erronenous conditions before transaction:
* Byte_Done, Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
- errmask=0x9f;
+ errmask = 0x9f;
} else {
- /* Erronenous conditions during transaction:
+ /* Erronenous conditions during transaction:
* Failed, Bus_Err, Dev_Err, Intr */
- errmask=0x1e;
+ errmask = 0x1e;
}
if (temp & errmask) {
dev_dbg(&I801_dev->dev, "SMBus busy (%02x). "
@@ -243,7 +278,7 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
dev_err(&I801_dev->dev,
"Reset failed! (%02x)\n", temp);
result = -1;
- goto END;
+ goto END;
}
if (i != 1) {
/* if die in middle of block transaction, fail */
@@ -261,33 +296,40 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
msleep(1);
temp = inb_p(SMBHSTSTS);
}
- while ((!(temp & 0x80))
- && (timeout++ < MAX_TIMEOUT));
+ while ((!(temp & SMBHSTSTS_BYTE_DONE))
+ && (timeout++ < MAX_TIMEOUT));
/* If the SMBus is still busy, we give up */
if (timeout >= MAX_TIMEOUT) {
+ /* try to stop the current command */
+ dev_dbg(&I801_dev->dev, "Terminating the current "
+ "operation\n");
+ outb_p(inb_p(SMBHSTCNT) | SMBHSTCNT_KILL, SMBHSTCNT);
+ msleep(1);
+ outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL),
+ SMBHSTCNT);
result = -1;
dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
}
- if (temp & 0x10) {
+ if (temp & SMBHSTSTS_FAILED) {
result = -1;
dev_dbg(&I801_dev->dev,
"Error: Failed bus transaction\n");
- } else if (temp & 0x08) {
+ } else if (temp & SMBHSTSTS_BUS_ERR) {
result = -1;
dev_err(&I801_dev->dev, "Bus collision!\n");
- } else if (temp & 0x04) {
+ } else if (temp & SMBHSTSTS_DEV_ERR) {
result = -1;
dev_dbg(&I801_dev->dev, "Error: no response!\n");
}
if (i == 1 && read_write == I2C_SMBUS_READ) {
len = inb_p(SMBHSTDAT0);
- if (len < 1)
- len = 1;
- if (len > 32)
- len = 32;
+ if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
+ result = -1;
+ goto END;
+ }
data->block[0] = len;
}
@@ -313,20 +355,9 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
goto END;
}
- if (hwpec) {
- /* wait for INTR bit as advised by Intel */
- timeout = 0;
- do {
- msleep(1);
- temp = inb_p(SMBHSTSTS);
- } while ((!(temp & 0x02))
- && (timeout++ < MAX_TIMEOUT));
+ if (hwpec)
+ i801_wait_hwpec();
- if (timeout >= MAX_TIMEOUT) {
- dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
- }
- outb_p(temp, SMBHSTSTS);
- }
result = 0;
END:
if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
@@ -393,7 +424,10 @@ static s32 i801_access(struct i2c_adapter * adap, u16 addr,
return -1;
}
- outb_p(hwpec, SMBAUXCTL); /* enable/disable hardware PEC */
+ if (hwpec) /* enable/disable hardware PEC */
+ outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_CRC, SMBAUXCTL);
+ else
+ outb_p(inb_p(SMBAUXCTL) & (~SMBAUXCTL_CRC), SMBAUXCTL);
if(block)
ret = i801_block_transaction(data, read_write, size, hwpec);
@@ -405,7 +439,7 @@ static s32 i801_access(struct i2c_adapter * adap, u16 addr,
/* Some BIOSes don't like it when PEC is enabled at reboot or resume
time, so we forcibly disable it after every transaction. */
if (hwpec)
- outb_p(0, SMBAUXCTL);
+ outb_p(inb_p(SMBAUXCTL) & (~SMBAUXCTL_CRC), SMBAUXCTL);
if(block)
return ret;
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