Re: [PATCH 7/8] drivers/i2c/busses/i2c-amd8111.c: Fix unsigned return type
From: Julia Lawall
Date: Thu Sep 30 2010 - 16:27:14 EST
The functions the functions amd_ec_wait_write and amd_ec_wait_read have an
unsigned return type, but return a negative constant to indicate an error
condition.
A sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@exists@
identifier f;
constant C;
@@
unsigned f(...)
{ <+...
* return -C;
...+> }
// </smpl>
Fixing amd_ec_wait_write and amd_ec_wait_read leads to the need to adjust
the return type of the functions amd_ec_write and amd_ec_read, which are
the only functions that call amd_ec_wait_write and amd_ec_wait_read.
amd_ec_write and amd_ec_read, in turn, are only called from within the
function amd8111_access, which already returns a signed typed value. Each
of the calls to amd_ec_write and amd_ec_read are updated using the
following semantic patch:
// <smpl>
@@
@@
+ status = amd_ec_write
- amd_ec_write
(...);
+ if (status) return status;
@@
@@
+ status = amd_ec_read
- amd_ec_read
(...);
+ if (status) return status;
// </smpl>
The patch also adds the declaration of the status variable.
Signed-off-by: Julia Lawall <julia@xxxxxxx>
---
Only compile tested.
drivers/i2c/busses/i2c-amd8111.c | 152 ++++++++++++++------
1 files changed, 110 insertions(+), 42 deletions(-)
diff --git a/drivers/i2c/busses/i2c-amd8111.c b/drivers/i2c/busses/i2c-amd8111.c
index af1e5e2..e12c584 100644
--- a/drivers/i2c/busses/i2c-amd8111.c
+++ b/drivers/i2c/busses/i2c-amd8111.c
@@ -69,7 +69,7 @@ static struct pci_driver amd8111_driver;
* ACPI 2.0 chapter 13 access of registers of the EC
*/
-static unsigned int amd_ec_wait_write(struct amd_smbus *smbus)
+static int amd_ec_wait_write(struct amd_smbus *smbus)
{
int timeout = 500;
@@ -85,7 +85,7 @@ static unsigned int amd_ec_wait_write(struct amd_smbus *smbus)
return 0;
}
-static unsigned int amd_ec_wait_read(struct amd_smbus *smbus)
+static int amd_ec_wait_read(struct amd_smbus *smbus)
{
int timeout = 500;
@@ -101,7 +101,7 @@ static unsigned int amd_ec_wait_read(struct amd_smbus *smbus)
return 0;
}
-static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
+static int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
unsigned char *data)
{
int status;
@@ -124,7 +124,7 @@ static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
return 0;
}
-static unsigned int amd_ec_write(struct amd_smbus *smbus, unsigned char address,
+static int amd_ec_write(struct amd_smbus *smbus, unsigned char address,
unsigned char data)
{
int status;
@@ -196,7 +196,7 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
{
struct amd_smbus *smbus = adap->algo_data;
unsigned char protocol, len, pec, temp[2];
- int i;
+ int i, status;
protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ
: AMD_SMB_PRTCL_WRITE;
@@ -209,38 +209,62 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
break;
case I2C_SMBUS_BYTE:
- if (read_write == I2C_SMBUS_WRITE)
- amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (read_write == I2C_SMBUS_WRITE) {
+ status = amd_ec_write(smbus, AMD_SMB_CMD,
+ command);
+ if (status)
+ return status;
+ }
protocol |= AMD_SMB_PRTCL_BYTE;
break;
case I2C_SMBUS_BYTE_DATA:
- amd_ec_write(smbus, AMD_SMB_CMD, command);
- if (read_write == I2C_SMBUS_WRITE)
- amd_ec_write(smbus, AMD_SMB_DATA, data->byte);
+ status = amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (status)
+ return status;
+ if (read_write == I2C_SMBUS_WRITE) {
+ status = amd_ec_write(smbus, AMD_SMB_DATA,
+ data->byte);
+ if (status)
+ return status;
+ }
protocol |= AMD_SMB_PRTCL_BYTE_DATA;
break;
case I2C_SMBUS_WORD_DATA:
- amd_ec_write(smbus, AMD_SMB_CMD, command);
+ status = amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (status)
+ return status;
if (read_write == I2C_SMBUS_WRITE) {
- amd_ec_write(smbus, AMD_SMB_DATA,
+ status = amd_ec_write(smbus, AMD_SMB_DATA,
data->word & 0xff);
- amd_ec_write(smbus, AMD_SMB_DATA + 1,
+ if (status)
+ return status;
+ status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
data->word >> 8);
+ if (status)
+ return status;
}
protocol |= AMD_SMB_PRTCL_WORD_DATA | pec;
break;
case I2C_SMBUS_BLOCK_DATA:
- amd_ec_write(smbus, AMD_SMB_CMD, command);
+ status = amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (status)
+ return status;
if (read_write == I2C_SMBUS_WRITE) {
len = min_t(u8, data->block[0],
I2C_SMBUS_BLOCK_MAX);
- amd_ec_write(smbus, AMD_SMB_BCNT, len);
- for (i = 0; i < len; i++)
- amd_ec_write(smbus, AMD_SMB_DATA + i,
- data->block[i + 1]);
+ status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
+ if (status)
+ return status;
+ for (i = 0; i < len; i++) {
+ status =
+ amd_ec_write(smbus, AMD_SMB_DATA + i,
+ data->block[i + 1]);
+ if (status)
+ return status;
+ }
}
protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec;
break;
@@ -248,19 +272,35 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
case I2C_SMBUS_I2C_BLOCK_DATA:
len = min_t(u8, data->block[0],
I2C_SMBUS_BLOCK_MAX);
- amd_ec_write(smbus, AMD_SMB_CMD, command);
- amd_ec_write(smbus, AMD_SMB_BCNT, len);
+ status = amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (status)
+ return status;
+ status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
+ if (status)
+ return status;
if (read_write == I2C_SMBUS_WRITE)
- for (i = 0; i < len; i++)
- amd_ec_write(smbus, AMD_SMB_DATA + i,
- data->block[i + 1]);
+ for (i = 0; i < len; i++) {
+ status =
+ amd_ec_write(smbus, AMD_SMB_DATA + i,
+ data->block[i + 1]);
+ if (status)
+ return status;
+ }
protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA;
break;
case I2C_SMBUS_PROC_CALL:
- amd_ec_write(smbus, AMD_SMB_CMD, command);
- amd_ec_write(smbus, AMD_SMB_DATA, data->word & 0xff);
- amd_ec_write(smbus, AMD_SMB_DATA + 1, data->word >> 8);
+ status = amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (status)
+ return status;
+ status = amd_ec_write(smbus, AMD_SMB_DATA,
+ data->word & 0xff);
+ if (status)
+ return status;
+ status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
+ data->word >> 8);
+ if (status)
+ return status;
protocol = AMD_SMB_PRTCL_PROC_CALL | pec;
read_write = I2C_SMBUS_READ;
break;
@@ -268,11 +308,18 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
case I2C_SMBUS_BLOCK_PROC_CALL:
len = min_t(u8, data->block[0],
I2C_SMBUS_BLOCK_MAX - 1);
- amd_ec_write(smbus, AMD_SMB_CMD, command);
- amd_ec_write(smbus, AMD_SMB_BCNT, len);
- for (i = 0; i < len; i++)
- amd_ec_write(smbus, AMD_SMB_DATA + i,
+ status = amd_ec_write(smbus, AMD_SMB_CMD, command);
+ if (status)
+ return status;
+ status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
+ if (status)
+ return status;
+ for (i = 0; i < len; i++) {
+ status = amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
+ if (status)
+ return status;
+ }
protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec;
read_write = I2C_SMBUS_READ;
break;
@@ -282,24 +329,34 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
return -EOPNOTSUPP;
}
- amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
- amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
+ status = amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
+ if (status)
+ return status;
+ status = amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
+ if (status)
+ return status;
/* FIXME this discards status from ec_read(); so temp[0] will
* hold stack garbage ... the rest of this routine will act
* nonsensically. Ignored ec_write() status might explain
* some such failures...
*/
- amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
+ status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
+ if (status)
+ return status;
if (~temp[0] & AMD_SMB_STS_DONE) {
udelay(500);
- amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
+ status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
+ if (status)
+ return status;
}
if (~temp[0] & AMD_SMB_STS_DONE) {
msleep(1);
- amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
+ status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
+ if (status)
+ return status;
}
if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS))
@@ -311,24 +368,35 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
switch (size) {
case I2C_SMBUS_BYTE:
case I2C_SMBUS_BYTE_DATA:
- amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
+ status = amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
+ if (status)
+ return status;
break;
case I2C_SMBUS_WORD_DATA:
case I2C_SMBUS_PROC_CALL:
- amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
- amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
+ status = amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
+ if (status)
+ return status;
+ status = amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
+ if (status)
+ return status;
data->word = (temp[1] << 8) | temp[0];
break;
case I2C_SMBUS_BLOCK_DATA:
case I2C_SMBUS_BLOCK_PROC_CALL:
- amd_ec_read(smbus, AMD_SMB_BCNT, &len);
+ status = amd_ec_read(smbus, AMD_SMB_BCNT, &len);
+ if (status)
+ return status;
len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
case I2C_SMBUS_I2C_BLOCK_DATA:
- for (i = 0; i < len; i++)
- amd_ec_read(smbus, AMD_SMB_DATA + i,
- data->block + i + 1);
+ for (i = 0; i < len; i++) {
+ status = amd_ec_read(smbus, AMD_SMB_DATA + i,
+ data->block + i + 1);
+ if (status)
+ return status;
+ }
data->block[0] = len;
break;
}
--
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