diff options
Diffstat (limited to 'drivers/i2c/i2c-core.c')
| -rw-r--r-- | drivers/i2c/i2c-core.c | 43 |
1 files changed, 27 insertions, 16 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 85e2e919d1cd..5ed622ee65c3 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -29,7 +29,6 @@ #include <linux/i2c.h> #include <linux/init.h> #include <linux/idr.h> -#include <linux/platform_device.h> #include <linux/mutex.h> #include <linux/completion.h> #include <linux/hardirq.h> @@ -451,16 +450,6 @@ static int i2c_register_adapter(struct i2c_adapter *adap) mutex_lock(&core_lock); - /* Add the adapter to the driver core. - * If the parent pointer is not set up, - * we add this adapter to the host bus. - */ - if (adap->dev.parent == NULL) { - adap->dev.parent = &platform_bus; - pr_debug("I2C adapter driver [%s] forgot to specify " - "physical device\n", adap->name); - } - /* Set default timeout to 1 second if not already set */ if (adap->timeout == 0) adap->timeout = HZ; @@ -1022,7 +1011,8 @@ module_exit(i2c_exit); */ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { - int ret; + unsigned long orig_jiffies; + int ret, try; /* REVISIT the fault reporting model here is weak: * @@ -1060,7 +1050,15 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) mutex_lock_nested(&adap->bus_lock, adap->level); } - ret = adap->algo->master_xfer(adap,msgs,num); + /* Retry automatically on arbitration loss */ + orig_jiffies = jiffies; + for (ret = 0, try = 0; try <= adap->retries; try++) { + ret = adap->algo->master_xfer(adap, msgs, num); + if (ret != -EAGAIN) + break; + if (time_after(jiffies, orig_jiffies + adap->timeout)) + break; + } mutex_unlock(&adap->bus_lock); return ret; @@ -1509,7 +1507,7 @@ struct i2c_adapter* i2c_get_adapter(int id) struct i2c_adapter *adapter; mutex_lock(&core_lock); - adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id); + adapter = idr_find(&i2c_adapter_idr, id); if (adapter && !try_module_get(adapter->owner)) adapter = NULL; @@ -1995,14 +1993,27 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, char read_write, u8 command, int protocol, union i2c_smbus_data *data) { + unsigned long orig_jiffies; + int try; s32 res; flags &= I2C_M_TEN | I2C_CLIENT_PEC; if (adapter->algo->smbus_xfer) { mutex_lock(&adapter->bus_lock); - res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write, - command, protocol, data); + + /* Retry automatically on arbitration loss */ + orig_jiffies = jiffies; + for (res = 0, try = 0; try <= adapter->retries; try++) { + res = adapter->algo->smbus_xfer(adapter, addr, flags, + read_write, command, + protocol, data); + if (res != -EAGAIN) + break; + if (time_after(jiffies, + orig_jiffies + adapter->timeout)) + break; + } mutex_unlock(&adapter->bus_lock); } else res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write, |
