linux/drivers/i2c/busses/i2c-nforce2-s4985.c
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00

250 lines
7.0 KiB
C

/*
* i2c-nforce2-s4985.c - i2c-nforce2 extras for the Tyan S4985 motherboard
*
* Copyright (C) 2008 Jean Delvare <jdelvare@suse.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
/*
* We select the channels by sending commands to the Philips
* PCA9556 chip at I2C address 0x18. The main adapter is used for
* the non-multiplexed part of the bus, and 4 virtual adapters
* are defined for the multiplexed addresses: 0x50-0x53 (memory
* module EEPROM) located on channels 1-4. We define one virtual
* adapter per CPU, which corresponds to one multiplexed channel:
* CPU0: virtual adapter 1, channel 1
* CPU1: virtual adapter 2, channel 2
* CPU2: virtual adapter 3, channel 3
* CPU3: virtual adapter 4, channel 4
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
extern struct i2c_adapter *nforce2_smbus;
static struct i2c_adapter *s4985_adapter;
static struct i2c_algorithm *s4985_algo;
/* Wrapper access functions for multiplexed SMBus */
static DEFINE_MUTEX(nforce2_lock);
static s32 nforce2_access_virt0(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
union i2c_smbus_data *data)
{
int error;
/* We exclude the multiplexed addresses */
if ((addr & 0xfc) == 0x50 || (addr & 0xfc) == 0x30
|| addr == 0x18)
return -ENXIO;
mutex_lock(&nforce2_lock);
error = nforce2_smbus->algo->smbus_xfer(adap, addr, flags, read_write,
command, size, data);
mutex_unlock(&nforce2_lock);
return error;
}
/* We remember the last used channels combination so as to only switch
channels when it is really needed. This greatly reduces the SMBus
overhead, but also assumes that nobody will be writing to the PCA9556
in our back. */
static u8 last_channels;
static inline s32 nforce2_access_channel(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
union i2c_smbus_data *data,
u8 channels)
{
int error;
/* We exclude the non-multiplexed addresses */
if ((addr & 0xfc) != 0x50 && (addr & 0xfc) != 0x30)
return -ENXIO;
mutex_lock(&nforce2_lock);
if (last_channels != channels) {
union i2c_smbus_data mplxdata;
mplxdata.byte = channels;
error = nforce2_smbus->algo->smbus_xfer(adap, 0x18, 0,
I2C_SMBUS_WRITE, 0x01,
I2C_SMBUS_BYTE_DATA,
&mplxdata);
if (error)
goto UNLOCK;
last_channels = channels;
}
error = nforce2_smbus->algo->smbus_xfer(adap, addr, flags, read_write,
command, size, data);
UNLOCK:
mutex_unlock(&nforce2_lock);
return error;
}
static s32 nforce2_access_virt1(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
union i2c_smbus_data *data)
{
/* CPU0: channel 1 enabled */
return nforce2_access_channel(adap, addr, flags, read_write, command,
size, data, 0x02);
}
static s32 nforce2_access_virt2(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
union i2c_smbus_data *data)
{
/* CPU1: channel 2 enabled */
return nforce2_access_channel(adap, addr, flags, read_write, command,
size, data, 0x04);
}
static s32 nforce2_access_virt3(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
union i2c_smbus_data *data)
{
/* CPU2: channel 3 enabled */
return nforce2_access_channel(adap, addr, flags, read_write, command,
size, data, 0x08);
}
static s32 nforce2_access_virt4(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size,
union i2c_smbus_data *data)
{
/* CPU3: channel 4 enabled */
return nforce2_access_channel(adap, addr, flags, read_write, command,
size, data, 0x10);
}
static int __init nforce2_s4985_init(void)
{
int i, error;
union i2c_smbus_data ioconfig;
if (!nforce2_smbus)
return -ENODEV;
/* Configure the PCA9556 multiplexer */
ioconfig.byte = 0x00; /* All I/O to output mode */
error = i2c_smbus_xfer(nforce2_smbus, 0x18, 0, I2C_SMBUS_WRITE, 0x03,
I2C_SMBUS_BYTE_DATA, &ioconfig);
if (error) {
dev_err(&nforce2_smbus->dev, "PCA9556 configuration failed\n");
error = -EIO;
goto ERROR0;
}
/* Unregister physical bus */
i2c_del_adapter(nforce2_smbus);
printk(KERN_INFO "Enabling SMBus multiplexing for Tyan S4985\n");
/* Define the 5 virtual adapters and algorithms structures */
s4985_adapter = kcalloc(5, sizeof(struct i2c_adapter), GFP_KERNEL);
if (!s4985_adapter) {
error = -ENOMEM;
goto ERROR1;
}
s4985_algo = kcalloc(5, sizeof(struct i2c_algorithm), GFP_KERNEL);
if (!s4985_algo) {
error = -ENOMEM;
goto ERROR2;
}
/* Fill in the new structures */
s4985_algo[0] = *(nforce2_smbus->algo);
s4985_algo[0].smbus_xfer = nforce2_access_virt0;
s4985_adapter[0] = *nforce2_smbus;
s4985_adapter[0].algo = s4985_algo;
s4985_adapter[0].dev.parent = nforce2_smbus->dev.parent;
for (i = 1; i < 5; i++) {
s4985_algo[i] = *(nforce2_smbus->algo);
s4985_adapter[i] = *nforce2_smbus;
snprintf(s4985_adapter[i].name, sizeof(s4985_adapter[i].name),
"SMBus nForce2 adapter (CPU%d)", i - 1);
s4985_adapter[i].algo = s4985_algo + i;
s4985_adapter[i].dev.parent = nforce2_smbus->dev.parent;
}
s4985_algo[1].smbus_xfer = nforce2_access_virt1;
s4985_algo[2].smbus_xfer = nforce2_access_virt2;
s4985_algo[3].smbus_xfer = nforce2_access_virt3;
s4985_algo[4].smbus_xfer = nforce2_access_virt4;
/* Register virtual adapters */
for (i = 0; i < 5; i++) {
error = i2c_add_adapter(s4985_adapter + i);
if (error) {
printk(KERN_ERR "i2c-nforce2-s4985: "
"Virtual adapter %d registration "
"failed, module not inserted\n", i);
for (i--; i >= 0; i--)
i2c_del_adapter(s4985_adapter + i);
goto ERROR3;
}
}
return 0;
ERROR3:
kfree(s4985_algo);
s4985_algo = NULL;
ERROR2:
kfree(s4985_adapter);
s4985_adapter = NULL;
ERROR1:
/* Restore physical bus */
i2c_add_adapter(nforce2_smbus);
ERROR0:
return error;
}
static void __exit nforce2_s4985_exit(void)
{
if (s4985_adapter) {
int i;
for (i = 0; i < 5; i++)
i2c_del_adapter(s4985_adapter+i);
kfree(s4985_adapter);
s4985_adapter = NULL;
}
kfree(s4985_algo);
s4985_algo = NULL;
/* Restore physical bus */
if (i2c_add_adapter(nforce2_smbus))
printk(KERN_ERR "i2c-nforce2-s4985: "
"Physical bus restoration failed\n");
}
MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
MODULE_DESCRIPTION("S4985 SMBus multiplexing");
MODULE_LICENSE("GPL");
module_init(nforce2_s4985_init);
module_exit(nforce2_s4985_exit);