Patch -km-3 :
Replace use of ADAP_LOCK and DRV_LOCK with down(&core_lists).
In many cases we need both, some return path forgot UNLOCK, and locks
were claimed in varying order and sometimes not at all.
Replace use of I2C_LOCK with down(&adapter->bus).
Remove unused adapter, driver and client counts.
--
Ky?sti M?lkki <kyosti.malkki at welho.com>
-------------- next part --------------
diff -ur lk-i2c-km-2/drivers/i2c/i2c-core.c lk-i2c-km-3/drivers/i2c/i2c-core.c
--- lk-i2c-km-2/drivers/i2c/i2c-core.c 2003-12-22 23:43:33.000000000 +0200
+++ lk-i2c-km-3/drivers/i2c/i2c-core.c 2003-12-23 12:36:43.000000000 +0200
@@ -34,32 +34,14 @@
/* ----- global defines ---------------------------------------------------- */
-/* exclusive access to the bus */
-#define I2C_LOCK(adap) down(&adap->lock)
-#define I2C_UNLOCK(adap) up(&adap->lock)
-
-#define ADAP_LOCK() down(&adap_lock)
-#define ADAP_UNLOCK() up(&adap_lock)
-
-#define DRV_LOCK() down(&driver_lock)
-#define DRV_UNLOCK() up(&driver_lock)
-
#define DEB(x) if (i2c_debug>=1) x;
#define DEB2(x) if (i2c_debug>=2) x;
/* ----- global variables -------------------------------------------------- */
-/**** lock for writing to global variables: the adapter & driver list */
-struct semaphore adap_lock;
-struct semaphore driver_lock;
-
-/**** adapter list */
+DECLARE_MUTEX(core_lists);
static struct i2c_adapter *adapters[I2C_ADAP_MAX];
-static int adap_count;
-
-/**** drivers list */
static struct i2c_driver *drivers[I2C_DRIVER_MAX];
-static int driver_count;
/**** debug level */
static int i2c_debug=1;
@@ -111,7 +93,7 @@
{
int i,j,res;
- ADAP_LOCK();
+ down(&core_lists);
for (i = 0; i < I2C_ADAP_MAX; i++)
if (NULL == adapters[i])
break;
@@ -124,12 +106,10 @@
}
adapters[i] = adap;
- adap_count++;
- ADAP_UNLOCK();
/* init data types */
- init_MUTEX(&adap->lock);
-
+ init_MUTEX(&adap->bus);
+ init_MUTEX(&adap->list);
#ifdef CONFIG_PROC_FS
if (i2cproc_initialized) {
@@ -154,36 +134,25 @@
#endif /* def CONFIG_PROC_FS */
/* inform drivers of new adapters */
- DRV_LOCK();
for (j=0;j<I2C_DRIVER_MAX;j++)
if (drivers[j]!=NULL &&
(drivers[j]->flags&(I2C_DF_NOTIFY|I2C_DF_DUMMY)))
/* We ignore the return code; if it fails, too bad */
drivers[j]->attach_adapter(adap);
- DRV_UNLOCK();
DEB(printk(KERN_DEBUG "i2c-core.o: adapter %s registered as adapter %d.\n",
adap->name,i));
-
- return 0;
-
-
-ERROR1:
- ADAP_LOCK();
- adapters[i] = NULL;
- adap_count--;
-ERROR0:
- ADAP_UNLOCK();
+ ERROR0:
+ up(&core_lists);
return res;
}
int i2c_del_adapter(struct i2c_adapter *adap)
{
- int i,j,res;
-
- ADAP_LOCK();
+ int i,j, res=0;
+ down(&core_lists);
for (i = 0; i < I2C_ADAP_MAX; i++)
if (adap == adapters[i])
break;
@@ -199,17 +168,14 @@
* *detach* it! Of course, each dummy driver should know about
* this or hell will break loose...
*/
- DRV_LOCK();
for (j = 0; j < I2C_DRIVER_MAX; j++)
if (drivers[j] && (drivers[j]->flags & I2C_DF_DUMMY))
if ((res = drivers[j]->attach_adapter(adap))) {
printk(KERN_WARNING "i2c-core.o: can't detach adapter %s "
"while detaching driver %s: driver not "
"detached!",adap->name,drivers[j]->name);
- goto ERROR1;
+ goto ERROR0;
}
- DRV_UNLOCK();
-
/* detach any active clients. This must be done first, because
* it can fail; in which case we give upp. */
@@ -237,17 +203,9 @@
#endif /* def CONFIG_PROC_FS */
adapters[i] = NULL;
- adap_count--;
-
- ADAP_UNLOCK();
- DEB(printk(KERN_DEBUG "i2c-core.o: adapter unregistered: %s\n",adap->name));
- return 0;
-
-ERROR0:
- ADAP_UNLOCK();
- return res;
-ERROR1:
- DRV_UNLOCK();
+ DEB(printk(KERN_DEBUG "i2c-core.o: adapter unregistered: %s\n",adap->name));
+ ERROR0:
+ up(&core_lists);
return res;
}
@@ -261,7 +219,8 @@
int i2c_add_driver(struct i2c_driver *driver)
{
int i;
- DRV_LOCK();
+
+ down(&core_lists);
for (i = 0; i < I2C_DRIVER_MAX; i++)
if (NULL == drivers[i])
break;
@@ -270,19 +229,12 @@
" i2c-core.o: register_driver(%s) "
"- enlarge I2C_DRIVER_MAX.\n",
driver->name);
- DRV_UNLOCK();
+ up(&core_lists);
return -ENOMEM;
}
-
- drivers[i] = driver;
- driver_count++;
-
- DRV_UNLOCK(); /* driver was successfully added */
-
+ drivers[i] = driver;
DEB(printk(KERN_DEBUG "i2c-core.o: driver %s registered.\n",driver->name));
- ADAP_LOCK();
-
/* now look for instances of driver on our adapters
*/
if (driver->flags& (I2C_DF_NOTIFY|I2C_DF_DUMMY)) {
@@ -291,15 +243,15 @@
/* Ignore errors */
driver->attach_adapter(adapters[i]);
}
- ADAP_UNLOCK();
+ up(&core_lists);
return 0;
}
int i2c_del_driver(struct i2c_driver *driver)
{
- int i,j,k,res;
+ int i,j,k,res = 0;
- DRV_LOCK();
+ down(&core_lists);
for (i = 0; i < I2C_DRIVER_MAX; i++)
if (driver == drivers[i])
break;
@@ -307,7 +259,7 @@
printk(KERN_WARNING " i2c-core.o: unregister_driver: "
"[%s] not found\n",
driver->name);
- DRV_UNLOCK();
+ up(&core_lists);
return -ENODEV;
}
/* Have a look at each adapter, if clients of this driver are still
@@ -319,7 +271,6 @@
* invalid operation might (will!) result, when using stale client
* pointers.
*/
- ADAP_LOCK(); /* should be moved inside the if statement... */
for (k=0;k<I2C_ADAP_MAX;k++) {
struct i2c_adapter *adap = adapters[k];
if (adap == NULL) /* skip empty entries. */
@@ -338,8 +289,7 @@
"not be detached properly; driver "
"not unloaded!",driver->name,
adap->name);
- ADAP_UNLOCK();
- return res;
+ goto ERROR0;
}
} else {
for (j=0;j<I2C_CLIENT_MAX;j++) {
@@ -362,31 +312,41 @@
driver->name,
client->addr,
adap->name);
- ADAP_UNLOCK();
- return res;
+ goto ERROR0;
}
}
}
}
}
- ADAP_UNLOCK();
drivers[i] = NULL;
- driver_count--;
- DRV_UNLOCK();
-
DEB(printk(KERN_DEBUG "i2c-core.o: driver unregistered: %s\n",driver->name));
- return 0;
+
+ ERROR0:
+ up(&core_lists);
+ return res;
}
-int i2c_check_addr (struct i2c_adapter *adapter, int addr)
+static int __i2c_check_addr (struct i2c_adapter *adapter, int addr)
{
int i;
for (i = 0; i < I2C_CLIENT_MAX ; i++)
if (adapter->clients[i] && (adapter->clients[i]->addr == addr))
return -EBUSY;
+
return 0;
}
+int i2c_check_addr (struct i2c_adapter *adapter, int addr)
+{
+ int rval;
+
+ down(&adapter->list);
+ rval = __i2c_check_addr(adapter, addr);
+ up(&adapter->list);
+
+ return rval;
+}
+
int i2c_attach_client(struct i2c_client *client)
{
struct i2c_adapter *adapter = client->adapter;
@@ -395,6 +355,7 @@
if (i2c_check_addr(client->adapter,client->addr))
return -EBUSY;
+ down(&adapter->list);
for (i = 0; i < I2C_CLIENT_MAX; i++)
if (NULL == adapter->clients[i])
break;
@@ -402,11 +363,11 @@
printk(KERN_WARNING
" i2c-core.o: attach_client(%s) - enlarge I2C_CLIENT_MAX.\n",
client->name);
+ up(&adapter->list);
return -ENOMEM;
}
-
adapter->clients[i] = client;
- adapter->client_count++;
+ up(&adapter->list);
if (adapter->client_register)
if (adapter->client_register(client))
@@ -428,16 +389,6 @@
struct i2c_adapter *adapter = client->adapter;
int i,res;
- for (i = 0; i < I2C_CLIENT_MAX; i++)
- if (client == adapter->clients[i])
- break;
- if (I2C_CLIENT_MAX == i) {
- printk(KERN_WARNING " i2c-core.o: unregister_client "
- "[%s] not found\n",
- client->name);
- return -ENODEV;
- }
-
if( (client->flags & I2C_CLIENT_ALLOW_USE) &&
(client->usage_count>0))
return -EBUSY;
@@ -449,8 +400,19 @@
return res;
}
+ down(&adapter->list);
+ for (i = 0; i < I2C_CLIENT_MAX; i++)
+ if (client == adapter->clients[i])
+ break;
+ if (I2C_CLIENT_MAX == i) {
+ printk(KERN_WARNING " i2c-core.o: unregister_client "
+ "[%s] not found\n",
+ client->name);
+ up(&adapter->list);
+ return -ENODEV;
+ }
adapter->clients[i] = NULL;
- adapter->client_count--;
+ up(&adapter->list);
DEB(printk(KERN_DEBUG "i2c-core.o: client [%s] unregistered.\n",client->name));
return 0;
@@ -482,6 +444,7 @@
client->adapter->dec_use(client->adapter);
}
+#if 0 /* just forget about this for now --km */
struct i2c_client *i2c_get_client(int driver_id, int adapter_id,
struct i2c_client *prev)
{
@@ -548,6 +511,7 @@
return 0;
}
+#endif
int i2c_use_client(struct i2c_client *client)
{
@@ -598,6 +562,7 @@
int i;
int nr = 0;
/* Note that it is safe to write a `little' beyond len. Yes, really. */
+ down(&core_lists);
for (i = 0; (i < I2C_ADAP_MAX) && (nr < len); i++)
if (adapters[i]) {
nr += sprintf(buf+nr, "i2c-%d\t", i);
@@ -614,6 +579,7 @@
adapters[i]->name,
adapters[i]->algo->name);
}
+ up(&core_lists);
return nr;
}
@@ -624,61 +590,77 @@
struct inode * inode = file->f_dentry->d_inode;
char *kbuf;
struct i2c_client *client;
+ struct i2c_adapter *adap;
int i,j,k,order_nr,len=0;
size_t len_total;
int order[I2C_CLIENT_MAX];
+#define OUTPUT_LENGTH_PER_LINE 70
- if (count > 4000)
- return -EINVAL;
len_total = file->f_pos + count;
- /* Too bad if this gets longer (unlikely) */
- if (len_total > 4000)
- len_total = 4000;
- for (i = 0; i < I2C_ADAP_MAX; i++)
- if (adapters[i]->inode == inode->i_ino) {
- /* We need a bit of slack in the kernel buffer; this makes the
- sprintf safe. */
- if (! (kbuf = kmalloc(count + 80,GFP_KERNEL)))
- return -ENOMEM;
- /* Order will hold the indexes of the clients
- sorted by address */
- order_nr=0;
- for (j = 0; j < I2C_CLIENT_MAX; j++) {
- if ((client = adapters[i]->clients[j]) &&
- (client->driver->id != I2C_DRIVERID_I2CDEV)) {
- for(k = order_nr;
- (k > 0) &&
- adapters[i]->clients[order[k-1]]->
- addr > client->addr;
- k--)
- order[k] = order[k-1];
- order[k] = j;
- order_nr++;
- }
- }
+ if (len_total > (I2C_CLIENT_MAX * OUTPUT_LENGTH_PER_LINE) )
+ /* adjust to maximum file size */
+ len_total = (I2C_CLIENT_MAX * OUTPUT_LENGTH_PER_LINE);
+
+ down(&core_lists);
+ /* adap = file->private_data; ?? --km */
+ for (i = 0; i < I2C_ADAP_MAX; i++) {
+ adap = adapters[i];
+ if (adap && (adap->inode == inode->i_ino))
+ break;
+ }
+ if ( I2C_ADAP_MAX == i ) {
+ up(&core_lists);
+ return -ENOENT;
+ }
+
+ /* We need a bit of slack in the kernel buffer; this makes the
+ sprintf safe. */
+ if (! (kbuf = kmalloc(len_total +
+ OUTPUT_LENGTH_PER_LINE,
+ GFP_KERNEL)))
+ return -ENOMEM;
+
+ /* Order will hold the indexes of the clients
+ sorted by address */
+ order_nr=0;
+ down(&adap->list);
+ for (j = 0; j < I2C_CLIENT_MAX; j++) {
+ if ((client = adap->clients[j]) &&
+ (client->driver->id != I2C_DRIVERID_I2CDEV)) {
+ for(k = order_nr;
+ (k > 0) &&
+ adap->clients[order[k-1]]->
+ addr > client->addr;
+ k--)
+ order[k] = order[k-1];
+ order[k] = j;
+ order_nr++;
+ }
+ }
- for (j = 0; (j < order_nr) && (len < len_total); j++) {
- client = adapters[i]->clients[order[j]];
- len += sprintf(kbuf+len,"%02x\t%-32s\t%-32s\n",
- client->addr,
- client->name,
- client->driver->name);
- }
- len = len - file->f_pos;
- if (len > count)
- len = count;
- if (len < 0)
- len = 0;
- if (copy_to_user (buf,kbuf+file->f_pos, len)) {
- kfree(kbuf);
- return -EFAULT;
- }
- file->f_pos += len;
- kfree(kbuf);
- return len;
- }
- return -ENOENT;
+ for (j = 0; (j < order_nr) && (len < len_total); j++) {
+ client = adap->clients[order[j]];
+ len += sprintf(kbuf+len,"%02x\t%-32s\t%-32s\n",
+ client->addr,
+ client->name,
+ client->driver->name);
+ }
+ up(&adap->list);
+ up(&core_lists);
+
+ len = len - file->f_pos;
+ if (len > count)
+ len = count;
+ if (len < 0)
+ len = 0;
+ if (copy_to_user (buf,kbuf+file->f_pos, len)) {
+ kfree(kbuf);
+ return -EFAULT;
+ }
+ file->f_pos += len;
+ kfree(kbuf);
+ return len;
}
static int __init i2cproc_init(void)
@@ -731,9 +713,9 @@
DEB2(printk(KERN_DEBUG "i2c-core.o: master_xfer: %s with %d msgs.\n",
adap->name,num));
- I2C_LOCK(adap);
+ down(&adap->bus);
ret = adap->algo->master_xfer(adap,msgs,num);
- I2C_UNLOCK(adap);
+ up(&adap->bus);
return ret;
} else {
@@ -758,9 +740,9 @@
DEB2(printk(KERN_DEBUG "i2c-core.o: master_send: writing %d bytes on %s.\n",
count,client->adapter->name));
- I2C_LOCK(adap);
+ down(&adap->bus);
ret = adap->algo->master_xfer(adap,&msg,1);
- I2C_UNLOCK(adap);
+ up(&adap->bus);
/* if everything went ok (i.e. 1 msg transmitted), return #bytes
* transmitted, else error code.
@@ -788,9 +770,9 @@
DEB2(printk(KERN_DEBUG "i2c-core.o: master_recv: reading %d bytes on %s.\n",
count,client->adapter->name));
- I2C_LOCK(adap);
+ down(&adap->bus);
ret = adap->algo->master_xfer(adap,&msg,1);
- I2C_UNLOCK(adap);
+ up(&adap->bus);
DEB2(printk(KERN_DEBUG "i2c-core.o: master_recv: return:%d (count:%d, addr:0x%02x)\n",
ret, count, client->addr));
@@ -1231,12 +1213,7 @@
printk(KERN_INFO "i2c-core.o: i2c core module version %s (%s)\n", I2C_VERSION, I2C_DATE);
memset(adapters,0,sizeof(adapters));
memset(drivers,0,sizeof(drivers));
- adap_count=0;
- driver_count=0;
- init_MUTEX(&adap_lock);
- init_MUTEX(&driver_lock);
-
i2cproc_init();
return 0;
Only in lk-i2c-km-3/drivers/i2c: i2c-core.c~
diff -ur lk-i2c-km-2/include/linux/i2c.h lk-i2c-km-3/include/linux/i2c.h
--- lk-i2c-km-2/include/linux/i2c.h 2003-12-23 00:41:41.000000000 +0200
+++ lk-i2c-km-3/include/linux/i2c.h 2003-12-23 12:33:15.000000000 +0200
@@ -235,11 +235,11 @@
/* and can be set via the i2c_ioctl call */
/* data fields that are valid for all devices */
- struct semaphore lock;
+ struct semaphore bus;
+ struct semaphore list;
unsigned int flags;/* flags specifying div. data */
struct i2c_client *clients[I2C_CLIENT_MAX];
- int client_count;
int timeout;
int retries;
Only in lk-i2c-km-3/include/linux: i2c.h~
