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path: root/drivers/i2c/busses/i2c-i801.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-i801.c')
-rw-r--r--drivers/i2c/busses/i2c-i801.c249
1 files changed, 166 insertions, 83 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 611b57192c96..289816db52ae 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -22,12 +22,12 @@
/*
SUPPORTED DEVICES PCI ID
- 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)
+ 82801AA 2413
+ 82801AB 2423
+ 82801BA 2443
+ 82801CA/CAM 2483
+ 82801DB 24C3 (HW PEC supported)
+ 82801EB 24D3 (HW PEC supported)
6300ESB 25A4
ICH6 266A
ICH7 27DA
@@ -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;
@@ -102,7 +114,7 @@ static struct pci_driver i801_driver;
static struct pci_dev *I801_dev;
static int isich4;
-static int i801_transaction(void)
+static int i801_transaction(int xact)
{
int temp;
int result = 0;
@@ -127,33 +139,40 @@ static int i801_transaction(void)
}
}
- outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
+ /* the current contents of SMBHSTCNT can be overwritten, since PEC,
+ * INTREN, SMBSCMD are passed in xact */
+ outb_p(xact | I801_START, SMBHSTCNT);
/* We will always wait for a fraction of a second! */
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");
}
@@ -172,44 +191,70 @@ static int i801_transaction(void)
return result;
}
-/* All-inclusive block transaction function */
-static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
- int command, int hwpec)
+/* 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);
+}
+
+static int i801_block_transaction_by_block(union i2c_smbus_data *data,
+ char read_write, int hwpec)
+{
+ int i, len;
+
+ inb_p(SMBHSTCNT); /* reset the data buffer index */
+
+ /* Use 32-byte buffer to process this transaction */
+ if (read_write == I2C_SMBUS_WRITE) {
+ len = data->block[0];
+ outb_p(len, SMBHSTDAT0);
+ for (i = 0; i < len; i++)
+ outb_p(data->block[i+1], SMBBLKDAT);
+ }
+
+ if (i801_transaction(I801_BLOCK_DATA | ENABLE_INT9 |
+ I801_PEC_EN * hwpec))
+ return -1;
+
+ if (read_write == I2C_SMBUS_READ) {
+ len = inb_p(SMBHSTDAT0);
+ if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
+ return -1;
+
+ data->block[0] = len;
+ for (i = 0; i < len; i++)
+ data->block[i + 1] = inb_p(SMBBLKDAT);
+ }
+ return 0;
+}
+
+static int i801_block_transaction_byte_by_byte(union i2c_smbus_data *data,
+ char read_write, int hwpec)
{
int i, len;
int smbcmd;
int temp;
int result = 0;
int timeout;
- unsigned char hostc, errmask;
+ unsigned char errmask;
- if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
- if (read_write == I2C_SMBUS_WRITE) {
- /* set I2C_EN bit in configuration register */
- pci_read_config_byte(I801_dev, SMBHSTCFG, &hostc);
- pci_write_config_byte(I801_dev, SMBHSTCFG,
- hostc | SMBHSTCFG_I2C_EN);
- } else {
- dev_err(&I801_dev->dev,
- "I2C_SMBUS_I2C_BLOCK_READ not DB!\n");
- return -1;
- }
- }
+ len = data->block[0];
if (read_write == I2C_SMBUS_WRITE) {
- len = data->block[0];
- if (len < 1)
- len = 1;
- if (len > 32)
- len = 32;
outb_p(len, SMBHSTDAT0);
outb_p(data->block[1], SMBBLKDAT);
- } else {
- len = 32; /* max for reads */
- }
-
- if(isich4 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
- /* set 32 byte buffer */
}
for (i = 1; i <= len; i++) {
@@ -227,13 +272,13 @@ 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:
+ /* Erroneous conditions before transaction:
* Byte_Done, Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
- errmask=0x9f;
+ errmask = 0x9f;
} else {
- /* Erronenous conditions during transaction:
+ /* Erroneous conditions during transaction:
* Failed, Bus_Err, Dev_Err, Intr */
- errmask=0x1e;
+ errmask = 0x1e;
}
if (temp & errmask) {
dev_dbg(&I801_dev->dev, "SMBus busy (%02x). "
@@ -242,14 +287,11 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
if (((temp = inb_p(SMBHSTSTS)) & errmask) != 0x00) {
dev_err(&I801_dev->dev,
"Reset failed! (%02x)\n", temp);
- result = -1;
- goto END;
+ return -1;
}
- if (i != 1) {
+ if (i != 1)
/* if die in middle of block transaction, fail */
- result = -1;
- goto END;
- }
+ return -1;
}
if (i == 1)
@@ -261,33 +303,38 @@ 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)
+ return -1;
data->block[0] = len;
}
@@ -310,25 +357,58 @@ static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
inb_p(SMBHSTDAT0), inb_p(SMBBLKDAT));
if (result < 0)
- goto END;
+ return result;
}
+ return result;
+}
- 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));
+static int i801_set_block_buffer_mode(void)
+{
+ outb_p(inb_p(SMBAUXCTL) | SMBAUXCTL_E32B, SMBAUXCTL);
+ if ((inb_p(SMBAUXCTL) & SMBAUXCTL_E32B) == 0)
+ return -1;
+ return 0;
+}
- if (timeout >= MAX_TIMEOUT) {
- dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
+/* Block transaction function */
+static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
+ int command, int hwpec)
+{
+ int result = 0;
+ unsigned char hostc;
+
+ if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
+ if (read_write == I2C_SMBUS_WRITE) {
+ /* set I2C_EN bit in configuration register */
+ pci_read_config_byte(I801_dev, SMBHSTCFG, &hostc);
+ pci_write_config_byte(I801_dev, SMBHSTCFG,
+ hostc | SMBHSTCFG_I2C_EN);
+ } else {
+ dev_err(&I801_dev->dev,
+ "I2C_SMBUS_I2C_BLOCK_READ not DB!\n");
+ return -1;
}
- outb_p(temp, SMBHSTSTS);
}
- result = 0;
-END:
+
+ if (read_write == I2C_SMBUS_WRITE) {
+ if (data->block[0] < 1)
+ data->block[0] = 1;
+ if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
+ data->block[0] = I2C_SMBUS_BLOCK_MAX;
+ } else {
+ data->block[0] = 32; /* max for reads */
+ }
+
+ if (isich4 && i801_set_block_buffer_mode() == 0 )
+ result = i801_block_transaction_by_block(data, read_write,
+ hwpec);
+ else
+ result = i801_block_transaction_byte_by_byte(data, read_write,
+ hwpec);
+
+ if (result == 0 && hwpec)
+ i801_wait_hwpec();
+
if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
/* restore saved configuration register value */
pci_write_config_byte(I801_dev, SMBHSTCFG, hostc);
@@ -393,19 +473,22 @@ 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);
- else {
- outb_p(xact | ENABLE_INT9, SMBHSTCNT);
- ret = i801_transaction();
- }
+ else
+ ret = i801_transaction(xact | ENABLE_INT9);
/* Some BIOSes don't like it when PEC is enabled at reboot or resume
- time, so we forcibly disable it after every transaction. */
+ time, so we forcibly disable it after every transaction. Turn off
+ E32B for the same reason. */
if (hwpec)
- outb_p(0, SMBAUXCTL);
+ outb_p(inb_p(SMBAUXCTL) & ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B),
+ SMBAUXCTL);
if(block)
return ret;
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-23 08:12:10 +0000