Commit 41535497 authored by Oleg Ryjkov's avatar Oleg Ryjkov Committed by Jean Delvare
Browse files

i2c-nforce2: Move status checking to a separate function



This is the first part of the patch that adds a function to reset the
nvidia MCP51/55 i2c controller, if something bad happens to it (e.g.
a slave sends a wrong byte count during a block transaction).

This patch just adds nforce2_check_status function. It was originally
written by Hans-Frieder Vogt.

The reason that I'm the one sending it is:
- I relied on it for the second part of the patch,
- It makes the driver code cleaner/better.

Signed-off-by: default avatarOleg Ryjkov <olegr@olegr.ca>
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
parent a202707e
......@@ -98,15 +98,40 @@ struct nforce2_smbus {
#define NVIDIA_SMB_PRTCL_BLOCK_DATA 0x0a
#define NVIDIA_SMB_PRTCL_PEC 0x80
/* Misc definitions */
#define MAX_TIMEOUT 100
static struct pci_driver nforce2_driver;
static int nforce2_check_status(struct i2c_adapter *adap)
{
struct nforce2_smbus *smbus = adap->algo_data;
int timeout = 0;
unsigned char temp;
do {
msleep(1);
temp = inb_p(NVIDIA_SMB_STS);
} while ((!temp) && (timeout++ < MAX_TIMEOUT));
if (timeout >= MAX_TIMEOUT) {
dev_dbg(&adap->dev, "SMBus Timeout!\n");
return -1;
}
if (!(temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) {
dev_dbg(&adap->dev, "Transaction failed (0x%02x)!\n", temp);
return -1;
}
return 0;
}
/* Return -1 on error */
static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size, union i2c_smbus_data * data)
{
struct nforce2_smbus *smbus = adap->algo_data;
unsigned char protocol, pec, temp;
unsigned char protocol, pec;
u8 len;
int i;
......@@ -170,21 +195,8 @@ static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR);
outb_p(protocol, NVIDIA_SMB_PRTCL);
temp = inb_p(NVIDIA_SMB_STS);
if (~temp & NVIDIA_SMB_STS_DONE) {
udelay(500);
temp = inb_p(NVIDIA_SMB_STS);
}
if (~temp & NVIDIA_SMB_STS_DONE) {
msleep(10);
temp = inb_p(NVIDIA_SMB_STS);
}
if ((~temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) {
dev_dbg(&adap->dev, "SMBus Timeout! (0x%02x)\n", temp);
if (nforce2_check_status(adap))
return -1;
}
if (read_write == I2C_SMBUS_WRITE)
return 0;
......@@ -202,7 +214,12 @@ static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
case I2C_SMBUS_BLOCK_DATA:
len = inb_p(NVIDIA_SMB_BCNT);
len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
if ((len <= 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
dev_err(&adap->dev, "Transaction failed "
"(received block size: 0x%02x)\n",
len);
return -1;
}
for (i = 0; i < len; i++)
data->block[i+1] = inb_p(NVIDIA_SMB_DATA + i);
data->block[0] = len;
......
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