From 0cc43a1806f078f7fd414850d8f1f1761696e4af Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Mon, 10 Jan 2011 22:11:23 +0100 Subject: i2c: Constify i2c_client where possible Helper functions for I2C and SMBus transactions don't modify the i2c_client that is passed to them, so it can be marked const. Signed-off-by: Jean Delvare --- drivers/i2c/i2c-core.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 6b4cc567645b..c7db6980e3a3 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1362,7 +1362,7 @@ EXPORT_SYMBOL(i2c_transfer); * * Returns negative errno, or else the number of bytes written. */ -int i2c_master_send(struct i2c_client *client, const char *buf, int count) +int i2c_master_send(const struct i2c_client *client, const char *buf, int count) { int ret; struct i2c_adapter *adap = client->adapter; @@ -1389,7 +1389,7 @@ EXPORT_SYMBOL(i2c_master_send); * * Returns negative errno, or else the number of bytes read. */ -int i2c_master_recv(struct i2c_client *client, char *buf, int count) +int i2c_master_recv(const struct i2c_client *client, char *buf, int count) { struct i2c_adapter *adap = client->adapter; struct i2c_msg msg; @@ -1679,7 +1679,7 @@ static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) * This executes the SMBus "receive byte" protocol, returning negative errno * else the byte received from the device. */ -s32 i2c_smbus_read_byte(struct i2c_client *client) +s32 i2c_smbus_read_byte(const struct i2c_client *client) { union i2c_smbus_data data; int status; @@ -1699,7 +1699,7 @@ EXPORT_SYMBOL(i2c_smbus_read_byte); * This executes the SMBus "send byte" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) +s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) { return i2c_smbus_xfer(client->adapter, client->addr, client->flags, I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); @@ -1714,7 +1714,7 @@ EXPORT_SYMBOL(i2c_smbus_write_byte); * This executes the SMBus "read byte" protocol, returning negative errno * else a data byte received from the device. */ -s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) +s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) { union i2c_smbus_data data; int status; @@ -1735,7 +1735,8 @@ EXPORT_SYMBOL(i2c_smbus_read_byte_data); * This executes the SMBus "write byte" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value) +s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, + u8 value) { union i2c_smbus_data data; data.byte = value; @@ -1753,7 +1754,7 @@ EXPORT_SYMBOL(i2c_smbus_write_byte_data); * This executes the SMBus "read word" protocol, returning negative errno * else a 16-bit unsigned "word" received from the device. */ -s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command) +s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) { union i2c_smbus_data data; int status; @@ -1774,7 +1775,8 @@ EXPORT_SYMBOL(i2c_smbus_read_word_data); * This executes the SMBus "write word" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value) +s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, + u16 value) { union i2c_smbus_data data; data.word = value; @@ -1793,7 +1795,8 @@ EXPORT_SYMBOL(i2c_smbus_write_word_data); * This executes the SMBus "process call" protocol, returning negative errno * else a 16-bit unsigned "word" received from the device. */ -s32 i2c_smbus_process_call(struct i2c_client *client, u8 command, u16 value) +s32 i2c_smbus_process_call(const struct i2c_client *client, u8 command, + u16 value) { union i2c_smbus_data data; int status; @@ -1821,7 +1824,7 @@ EXPORT_SYMBOL(i2c_smbus_process_call); * support this; its emulation through I2C messaging relies on a specific * mechanism (I2C_M_RECV_LEN) which may not be implemented. */ -s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, u8 *values) { union i2c_smbus_data data; @@ -1848,7 +1851,7 @@ EXPORT_SYMBOL(i2c_smbus_read_block_data); * This executes the SMBus "block write" protocol, returning negative errno * else zero on success. */ -s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values) { union i2c_smbus_data data; @@ -1864,7 +1867,7 @@ s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, EXPORT_SYMBOL(i2c_smbus_write_block_data); /* Returns the number of read bytes */ -s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, u8 *values) { union i2c_smbus_data data; @@ -1884,7 +1887,7 @@ s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, } EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); -s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, +s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, u8 length, const u8 *values) { union i2c_smbus_data data; -- cgit v1.2.3 From 5219bf884b6e2b54e734ca1799b6f0014bb2b4b7 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Fri, 14 Jan 2011 22:03:49 +0100 Subject: i2c: Unregister dummy devices last on adapter removal Remove real devices first and dummy devices last. This gives device driver which instantiated dummy devices themselves a chance to clean them up before we do. Signed-off-by: Jean Delvare Tested-by: Hans Verkuil Cc: stable@kernel.org --- drivers/i2c/i2c-core.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index c7db6980e3a3..b916675605b4 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1019,6 +1019,14 @@ static int i2c_do_del_adapter(struct i2c_driver *driver, } static int __unregister_client(struct device *dev, void *dummy) +{ + struct i2c_client *client = i2c_verify_client(dev); + if (client && strcmp(client->name, "dummy")) + i2c_unregister_device(client); + return 0; +} + +static int __unregister_dummy(struct device *dev, void *dummy) { struct i2c_client *client = i2c_verify_client(dev); if (client) @@ -1075,8 +1083,12 @@ int i2c_del_adapter(struct i2c_adapter *adap) mutex_unlock(&adap->userspace_clients_lock); /* Detach any active clients. This can't fail, thus we do not - checking the returned value. */ + * check the returned value. This is a two-pass process, because + * we can't remove the dummy devices during the first pass: they + * could have been instantiated by real devices wishing to clean + * them up properly, so we give them a chance to do that first. */ res = device_for_each_child(&adap->dev, NULL, __unregister_client); + res = device_for_each_child(&adap->dev, NULL, __unregister_dummy); #ifdef CONFIG_I2C_COMPAT class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, -- cgit v1.2.3 From d529de2994880d345d7588f92d5a426f63089ba3 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Fri, 14 Jan 2011 22:03:49 +0100 Subject: i2c: Factor out runtime suspend checks from PM operations When devices use dev_pm_ops the I2C API is implementing standard functionality for integration with runtime PM and for checking for the presence of a per device op. The PM core provides pm_generic_ functions implementing this behaviour - use them to reduce coupling with future PM updates. Signed-off-by: Mark Brown Signed-off-by: Jean Delvare --- drivers/i2c/i2c-core.c | 68 +++++++++++++++----------------------------------- 1 file changed, 20 insertions(+), 48 deletions(-) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index b916675605b4..0f9dc7dc15f1 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -196,88 +196,60 @@ static int i2c_device_pm_suspend(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm) { - if (pm_runtime_suspended(dev)) - return 0; - else - return pm->suspend ? pm->suspend(dev) : 0; - } - - return i2c_legacy_suspend(dev, PMSG_SUSPEND); + if (pm) + return pm_generic_suspend(dev); + else + return i2c_legacy_suspend(dev, PMSG_SUSPEND); } static int i2c_device_pm_resume(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - int ret; if (pm) - ret = pm->resume ? pm->resume(dev) : 0; + return pm_generic_resume(dev); else - ret = i2c_legacy_resume(dev); - - return ret; + return i2c_legacy_resume(dev); } static int i2c_device_pm_freeze(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm) { - if (pm_runtime_suspended(dev)) - return 0; - else - return pm->freeze ? pm->freeze(dev) : 0; - } - - return i2c_legacy_suspend(dev, PMSG_FREEZE); + if (pm) + return pm_generic_freeze(dev); + else + return i2c_legacy_suspend(dev, PMSG_FREEZE); } static int i2c_device_pm_thaw(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm) { - if (pm_runtime_suspended(dev)) - return 0; - else - return pm->thaw ? pm->thaw(dev) : 0; - } - - return i2c_legacy_resume(dev); + if (pm) + return pm_generic_thaw(dev); + else + return i2c_legacy_resume(dev); } static int i2c_device_pm_poweroff(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (pm) { - if (pm_runtime_suspended(dev)) - return 0; - else - return pm->poweroff ? pm->poweroff(dev) : 0; - } - - return i2c_legacy_suspend(dev, PMSG_HIBERNATE); + if (pm) + return pm_generic_poweroff(dev); + else + return i2c_legacy_suspend(dev, PMSG_HIBERNATE); } static int i2c_device_pm_restore(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - int ret; if (pm) - ret = pm->restore ? pm->restore(dev) : 0; + return pm_generic_restore(dev); else - ret = i2c_legacy_resume(dev); - - if (!ret) { - pm_runtime_disable(dev); - pm_runtime_set_active(dev); - pm_runtime_enable(dev); - } - - return ret; + return i2c_legacy_resume(dev); } #else /* !CONFIG_PM_SLEEP */ #define i2c_device_pm_suspend NULL -- cgit v1.2.3 From f4e8db31a83ad019e9ae06edb9c2f89de66bc7b7 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Fri, 14 Jan 2011 22:03:50 +0100 Subject: i2c: Encourage move to dev_pm_ops by warning on use of legacy methods Since the PM core wishes to transition away from the legacy suspend and resume methods and since removing them makes using PM core features like runtime PM much easier start warning when a driver is registered using the legacy methods. Signed-off-by: Mark Brown Signed-off-by: Jean Delvare --- drivers/i2c/i2c-core.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/i2c/i2c-core.c') diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 0f9dc7dc15f1..f0bd5bcdf563 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -1124,6 +1124,14 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver) if (res) return res; + /* Drivers should switch to dev_pm_ops instead. */ + if (driver->suspend) + pr_warn("i2c-core: driver [%s] using legacy suspend method\n", + driver->driver.name); + if (driver->resume) + pr_warn("i2c-core: driver [%s] using legacy resume method\n", + driver->driver.name); + pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); INIT_LIST_HEAD(&driver->clients); -- cgit v1.2.3