diff options
Diffstat (limited to 'drivers/i2c/i2c-core-base.c')
-rw-r--r-- | drivers/i2c/i2c-core-base.c | 147 |
1 files changed, 122 insertions, 25 deletions
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 38af18645133..d389d4fb0623 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -185,7 +185,7 @@ static int i2c_generic_bus_free(struct i2c_adapter *adap) int i2c_generic_scl_recovery(struct i2c_adapter *adap) { struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; - int i = 0, scl = 1, ret; + int i = 0, scl = 1, ret = 0; if (bri->prepare_recovery) bri->prepare_recovery(adap); @@ -327,6 +327,8 @@ static int i2c_device_probe(struct device *dev) if (client->flags & I2C_CLIENT_HOST_NOTIFY) { dev_dbg(dev, "Using Host Notify IRQ\n"); + /* Keep adapter active when Host Notify is required */ + pm_runtime_get_sync(&client->adapter->dev); irq = i2c_smbus_host_notify_to_irq(client); } else if (dev->of_node) { irq = of_irq_get_byname(dev->of_node, "irq"); @@ -431,6 +433,8 @@ static int i2c_device_remove(struct device *dev) device_init_wakeup(&client->dev, false); client->irq = client->init_irq; + if (client->flags & I2C_CLIENT_HOST_NOTIFY) + pm_runtime_put(&client->adapter->dev); return status; } @@ -710,7 +714,7 @@ static int i2c_dev_irq_from_resources(const struct resource *resources, } /** - * i2c_new_device - instantiate an i2c device + * i2c_new_client_device - instantiate an i2c device * @adap: the adapter managing the device * @info: describes one I2C device; bus_num is ignored * Context: can sleep @@ -723,17 +727,17 @@ static int i2c_dev_irq_from_resources(const struct resource *resources, * before any i2c_adapter could exist. * * This returns the new i2c client, which may be saved for later use with - * i2c_unregister_device(); or NULL to indicate an error. + * i2c_unregister_device(); or an ERR_PTR to describe the error. */ -struct i2c_client * -i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) +static struct i2c_client * +i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) { struct i2c_client *client; int status; client = kzalloc(sizeof *client, GFP_KERNEL); if (!client) - return NULL; + return ERR_PTR(-ENOMEM); client->adapter = adap; @@ -799,7 +803,31 @@ out_err: client->name, client->addr, status); out_err_silent: kfree(client); - return NULL; + return ERR_PTR(status); +} +EXPORT_SYMBOL_GPL(i2c_new_client_device); + +/** + * i2c_new_device - instantiate an i2c device + * @adap: the adapter managing the device + * @info: describes one I2C device; bus_num is ignored + * Context: can sleep + * + * This deprecated function has the same functionality as + * @i2c_new_client_device, it just returns NULL instead of an ERR_PTR in case of + * an error for compatibility with current I2C API. It will be removed once all + * users are converted. + * + * This returns the new i2c client, which may be saved for later use with + * i2c_unregister_device(); or NULL to indicate an error. + */ +struct i2c_client * +i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) +{ + struct i2c_client *ret; + + ret = i2c_new_client_device(adap, info); + return IS_ERR(ret) ? NULL : ret; } EXPORT_SYMBOL_GPL(i2c_new_device); @@ -850,7 +878,7 @@ static struct i2c_driver dummy_driver = { }; /** - * i2c_new_dummy - return a new i2c device bound to a dummy driver + * i2c_new_dummy_device - return a new i2c device bound to a dummy driver * @adapter: the adapter managing the device * @address: seven bit address to be used * Context: can sleep @@ -865,18 +893,86 @@ static struct i2c_driver dummy_driver = { * different driver. * * This returns the new i2c client, which should be saved for later use with - * i2c_unregister_device(); or NULL to indicate an error. + * i2c_unregister_device(); or an ERR_PTR to describe the error. */ -struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) +static struct i2c_client * +i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address) { struct i2c_board_info info = { I2C_BOARD_INFO("dummy", address), }; - return i2c_new_device(adapter, &info); + return i2c_new_client_device(adapter, &info); +} +EXPORT_SYMBOL_GPL(i2c_new_dummy_device); + +/** + * i2c_new_dummy - return a new i2c device bound to a dummy driver + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This deprecated function has the same functionality as @i2c_new_dummy_device, + * it just returns NULL instead of an ERR_PTR in case of an error for + * compatibility with current I2C API. It will be removed once all users are + * converted. + * + * This returns the new i2c client, which should be saved for later use with + * i2c_unregister_device(); or NULL to indicate an error. + */ +struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) +{ + struct i2c_client *ret; + + ret = i2c_new_dummy_device(adapter, address); + return IS_ERR(ret) ? NULL : ret; } EXPORT_SYMBOL_GPL(i2c_new_dummy); +struct i2c_dummy_devres { + struct i2c_client *client; +}; + +static void devm_i2c_release_dummy(struct device *dev, void *res) +{ + struct i2c_dummy_devres *this = res; + + i2c_unregister_device(this->client); +} + +/** + * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver + * @dev: device the managed resource is bound to + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This is the device-managed version of @i2c_new_dummy_device. It returns the + * new i2c client or an ERR_PTR in case of an error. + */ +struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, + struct i2c_adapter *adapter, + u16 address) +{ + struct i2c_dummy_devres *dr; + struct i2c_client *client; + + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + client = i2c_new_dummy_device(adapter, address); + if (IS_ERR(client)) { + devres_free(dr); + } else { + dr->client = client; + devres_add(dev, dr); + } + + return client; +} +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); + /** * i2c_new_secondary_device - Helper to get the instantiated secondary address * and create the associated device @@ -996,9 +1092,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, info.flags |= I2C_CLIENT_SLAVE; } - client = i2c_new_device(adap, &info); - if (!client) - return -EINVAL; + client = i2c_new_client_device(adap, &info); + if (IS_ERR(client)) + return PTR_ERR(client); /* Keep track of the added device */ mutex_lock(&adap->userspace_clients_lock); @@ -1867,8 +1963,10 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) if (WARN_ON(!msgs || num < 1)) return -EINVAL; - if (WARN_ON(test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags))) - return -ESHUTDOWN; + + ret = __i2c_check_suspended(adap); + if (ret) + return ret; if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) return -EOPNOTSUPP; @@ -1890,7 +1988,11 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int 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 (i2c_in_atomic_xfer_mode() && adap->algo->master_xfer_atomic) + ret = adap->algo->master_xfer_atomic(adap, msgs, num); + else + ret = adap->algo->master_xfer(adap, msgs, num); + if (ret != -EAGAIN) break; if (time_after(jiffies, orig_jiffies + adap->timeout)) @@ -1946,14 +2048,9 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) * one (discarding status on the second message) or errno * (discarding status on the first one). */ - if (in_atomic() || irqs_disabled()) { - ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT); - if (!ret) - /* I2C activity is ongoing. */ - return -EAGAIN; - } else { - i2c_lock_bus(adap, I2C_LOCK_SEGMENT); - } + ret = __i2c_lock_bus_helper(adap); + if (ret) + return ret; ret = __i2c_transfer(adap, msgs, num); i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); |