From b2433d861eaf349f4dcdc9281e75b139c1809dd3 Mon Sep 17 00:00:00 2001 From: Geoff Thorpe Date: Wed, 2 Nov 2011 11:44:44 -0400 Subject: uio: documentation fixups The 'name' attribute of struct uio_mem wasn't documented, and the note about 'kobj' is stale and needs to be changed to 'map'. Signed-off-by: Geoff Thorpe Signed-off-by: "Hans J. Koch" Signed-off-by: Greg Kroah-Hartman --- Documentation/DocBook/uio-howto.tmpl | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl index 54883de5d5f9..ac3d0018140c 100644 --- a/Documentation/DocBook/uio-howto.tmpl +++ b/Documentation/DocBook/uio-howto.tmpl @@ -520,6 +520,11 @@ Here's a description of the fields of struct uio_mem: + +const char *name: Optional. Set this to help identify +the memory region, it will show up in the corresponding sysfs node. + + int memtype: Required if the mapping is used. Set this to UIO_MEM_PHYS if you you have physical memory on your @@ -553,7 +558,7 @@ instead to remember such an address. -Please do not touch the kobj element of +Please do not touch the map element of struct uio_mem! It is used by the UIO framework to set up sysfs files for this mapping. Simply leave it alone. -- cgit v1.2.3 From 93f3350c46fa5dfcc9650eb19b186e71ffc924c3 Mon Sep 17 00:00:00 2001 From: Claudio Scordino Date: Wed, 9 Nov 2011 15:51:49 +0100 Subject: RS485: fix inconsistencies in the meaning of some variables The crisv10.c and the atmel_serial.c serial drivers intepret the fields of the serial_rs485 structure in a different way. In particular, crisv10.c uses SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND for the voltage of the RTS pin; atmel_serial.c, instead, uses these values to know if a delay must be set before and after sending. This patch makes the usage of these variables consistent across all drivers and fixes the Documentation as well. From now on, SER_RS485_RTS_AFTER_SEND and SER_RS485_RTS_ON_SEND will be used to set the voltage of the RTS pin (as in the crisv10.c driver); the delay will be understood by looking only at the value of delay_rts_before_send and delay_rts_after_send. Signed-off-by: Claudio Scordino Signed-off-by: Darron Black Acked-by: Jesper Nilsson Acked-by: Nicolas Ferre Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- Documentation/serial/serial-rs485.txt | 14 +++++++++++--- drivers/tty/serial/atmel_serial.c | 16 +++------------- drivers/tty/serial/crisv10.c | 10 ++-------- include/linux/serial.h | 14 ++++++++------ 4 files changed, 24 insertions(+), 30 deletions(-) (limited to 'Documentation') diff --git a/Documentation/serial/serial-rs485.txt b/Documentation/serial/serial-rs485.txt index 079cb3df62cf..41c8378c0b2f 100644 --- a/Documentation/serial/serial-rs485.txt +++ b/Documentation/serial/serial-rs485.txt @@ -97,15 +97,23 @@ struct serial_rs485 rs485conf; - /* Set RS485 mode: */ + /* Enable RS485 mode: */ rs485conf.flags |= SER_RS485_ENABLED; + /* Set logical level for RTS pin equal to 1 when sending: */ + rs485conf.flags |= SER_RS485_RTS_ON_SEND; + /* or, set logical level for RTS pin equal to 0 when sending: */ + rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND); + + /* Set logical level for RTS pin equal to 1 after sending: */ + rs485conf.flags |= SER_RS485_RTS_AFTER_SEND; + /* or, set logical level for RTS pin equal to 0 after sending: */ + rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND); + /* Set rts delay before send, if needed: */ - rs485conf.flags |= SER_RS485_RTS_BEFORE_SEND; rs485conf.delay_rts_before_send = ...; /* Set rts delay after send, if needed: */ - rs485conf.flags |= SER_RS485_RTS_AFTER_SEND; rs485conf.delay_rts_after_send = ...; /* Set this flag if you want to receive data even whilst sending data */ diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 4a0f86fa1e90..4c823f341d98 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -228,7 +228,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf) if (rs485conf->flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); atmel_port->tx_done_mask = ATMEL_US_TXEMPTY; - if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND) + if ((rs485conf->delay_rts_after_send) > 0) UART_PUT_TTGR(port, rs485conf->delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; } else { @@ -304,7 +304,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl) if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + if ((atmel_port->rs485.delay_rts_after_send) > 0) UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; @@ -1228,7 +1228,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, if (atmel_port->rs485.flags & SER_RS485_ENABLED) { dev_dbg(port->dev, "Setting UART to RS485\n"); - if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + if ((atmel_port->rs485.delay_rts_after_send) > 0) UART_PUT_TTGR(port, atmel_port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; @@ -1447,16 +1447,6 @@ static void __devinit atmel_of_init_port(struct atmel_uart_port *atmel_port, rs485conf->delay_rts_after_send = rs485_delay[1]; rs485conf->flags = 0; - if (rs485conf->delay_rts_before_send == 0 && - rs485conf->delay_rts_after_send == 0) { - rs485conf->flags |= SER_RS485_RTS_ON_SEND; - } else { - if (rs485conf->delay_rts_before_send) - rs485conf->flags |= SER_RS485_RTS_BEFORE_SEND; - if (rs485conf->delay_rts_after_send) - rs485conf->flags |= SER_RS485_RTS_AFTER_SEND; - } - if (of_get_property(np, "rs485-rx-during-tx", NULL)) rs485conf->flags |= SER_RS485_RX_DURING_TX; diff --git a/drivers/tty/serial/crisv10.c b/drivers/tty/serial/crisv10.c index b7435043f2fe..1dfba7b779c8 100644 --- a/drivers/tty/serial/crisv10.c +++ b/drivers/tty/serial/crisv10.c @@ -3234,9 +3234,8 @@ rs_write(struct tty_struct *tty, e100_disable_rx(info); e100_enable_rx_irq(info); #endif - if ((info->rs485.flags & SER_RS485_RTS_BEFORE_SEND) && - (info->rs485.delay_rts_before_send > 0)) - msleep(info->rs485.delay_rts_before_send); + if (info->rs485.delay_rts_before_send > 0) + msleep(info->rs485.delay_rts_before_send); } #endif /* CONFIG_ETRAX_RS485 */ @@ -3693,10 +3692,6 @@ rs_ioctl(struct tty_struct *tty, rs485data.delay_rts_before_send = rs485ctrl.delay_rts_before_send; rs485data.flags = 0; - if (rs485data.delay_rts_before_send != 0) - rs485data.flags |= SER_RS485_RTS_BEFORE_SEND; - else - rs485data.flags &= ~(SER_RS485_RTS_BEFORE_SEND); if (rs485ctrl.enabled) rs485data.flags |= SER_RS485_ENABLED; @@ -4531,7 +4526,6 @@ static int __init rs_init(void) /* Set sane defaults */ info->rs485.flags &= ~(SER_RS485_RTS_ON_SEND); info->rs485.flags |= SER_RS485_RTS_AFTER_SEND; - info->rs485.flags &= ~(SER_RS485_RTS_BEFORE_SEND); info->rs485.delay_rts_before_send = 0; info->rs485.flags &= ~(SER_RS485_ENABLED); #endif diff --git a/include/linux/serial.h b/include/linux/serial.h index 97ff8e27a6cc..3d86517fe7d5 100644 --- a/include/linux/serial.h +++ b/include/linux/serial.h @@ -207,13 +207,15 @@ struct serial_icounter_struct { struct serial_rs485 { __u32 flags; /* RS485 feature flags */ -#define SER_RS485_ENABLED (1 << 0) -#define SER_RS485_RTS_ON_SEND (1 << 1) -#define SER_RS485_RTS_AFTER_SEND (1 << 2) -#define SER_RS485_RTS_BEFORE_SEND (1 << 3) +#define SER_RS485_ENABLED (1 << 0) /* If enabled */ +#define SER_RS485_RTS_ON_SEND (1 << 1) /* Logical level for + RTS pin when + sending */ +#define SER_RS485_RTS_AFTER_SEND (1 << 2) /* Logical level for + RTS pin after sent*/ #define SER_RS485_RX_DURING_TX (1 << 4) - __u32 delay_rts_before_send; /* Milliseconds */ - __u32 delay_rts_after_send; /* Milliseconds */ + __u32 delay_rts_before_send; /* Delay before send (milliseconds) */ + __u32 delay_rts_after_send; /* Delay after send (milliseconds) */ __u32 padding[5]; /* Memory is cheap, new structs are a royal PITA .. */ }; -- cgit v1.2.3 From cbb44514048a250647c6c6b3df27ff62cb71f7d5 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Wed, 23 Nov 2011 11:33:07 +0100 Subject: i2c: Fix device name for 10-bit slave address 10-bit addresses overlap with traditional 7-bit addresses, leading in device name collisions. Add an arbitrary offset to 10-bit addresses to prevent this collision. The offset was chosen so that the address is still easily recognizable. Signed-off-by: Jean Delvare Acked-by: Wolfram Sang --- Documentation/i2c/ten-bit-addresses | 36 +++++++++++++++++++----------------- drivers/i2c/i2c-core.c | 4 +++- 2 files changed, 22 insertions(+), 18 deletions(-) (limited to 'Documentation') diff --git a/Documentation/i2c/ten-bit-addresses b/Documentation/i2c/ten-bit-addresses index e9890709c508..cdfe13901b99 100644 --- a/Documentation/i2c/ten-bit-addresses +++ b/Documentation/i2c/ten-bit-addresses @@ -1,22 +1,24 @@ The I2C protocol knows about two kinds of device addresses: normal 7 bit addresses, and an extended set of 10 bit addresses. The sets of addresses do not intersect: the 7 bit address 0x10 is not the same as the 10 bit -address 0x10 (though a single device could respond to both of them). You -select a 10 bit address by adding an extra byte after the address -byte: - S Addr7 Rd/Wr .... -becomes - S 11110 Addr10 Rd/Wr -S is the start bit, Rd/Wr the read/write bit, and if you count the number -of bits, you will see the there are 8 after the S bit for 7 bit addresses, -and 16 after the S bit for 10 bit addresses. +address 0x10 (though a single device could respond to both of them). -WARNING! The current 10 bit address support is EXPERIMENTAL. There are -several places in the code that will cause SEVERE PROBLEMS with 10 bit -addresses, even though there is some basic handling and hooks. Also, -almost no supported adapter handles the 10 bit addresses correctly. +I2C messages to and from 10-bit address devices have a different format. +See the I2C specification for the details. -As soon as a real 10 bit address device is spotted 'in the wild', we -can and will add proper support. Right now, 10 bit address devices -are defined by the I2C protocol, but we have never seen a single device -which supports them. +The current 10 bit address support is minimal. It should work, however +you can expect some problems along the way: +* Not all bus drivers support 10-bit addresses. Some don't because the + hardware doesn't support them (SMBus doesn't require 10-bit address + support for example), some don't because nobody bothered adding the + code (or it's there but not working properly.) Software implementation + (i2c-algo-bit) is known to work. +* Some optional features do not support 10-bit addresses. This is the + case of automatic detection and instantiation of devices by their, + drivers, for example. +* Many user-space packages (for example i2c-tools) lack support for + 10-bit addresses. + +Note that 10-bit address devices are still pretty rare, so the limitations +listed above could stay for a long time, maybe even forever if nobody +needs them to be fixed. diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 131079a3e292..1e5606185b4f 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -539,8 +539,10 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) client->dev.type = &i2c_client_type; client->dev.of_node = info->of_node; + /* For 10-bit clients, add an arbitrary offset to avoid collisions */ dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), - client->addr); + client->addr | ((client->flags & I2C_CLIENT_TEN) + ? 0xa000 : 0)); status = device_register(&client->dev); if (status) goto out_err; -- cgit v1.2.3 From 5841eb6402707a387b216373e65c9c28e8136663 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 23 Nov 2011 21:18:39 +0100 Subject: PM / Domains: Document how PM domains are used by the PM core The current power management documentation in Documentation/power/ either doesn't cover PM domains at all, or gives inaccurate information about them, so update the relevant files in there to follow the code. Signed-off-by: Rafael J. Wysocki --- Documentation/power/devices.txt | 42 ++++++++++++++++++++++++-------------- Documentation/power/runtime_pm.txt | 29 ++++++++++++++++---------- 2 files changed, 45 insertions(+), 26 deletions(-) (limited to 'Documentation') diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 646a89e0c07d..4342acbeee10 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -123,9 +123,10 @@ please refer directly to the source code for more information about it. Subsystem-Level Methods ----------------------- The core methods to suspend and resume devices reside in struct dev_pm_ops -pointed to by the pm member of struct bus_type, struct device_type and -struct class. They are mostly of interest to the people writing infrastructure -for buses, like PCI or USB, or device type and device class drivers. +pointed to by the ops member of struct dev_pm_domain, or by the pm member of +struct bus_type, struct device_type and struct class. They are mostly of +interest to the people writing infrastructure for platforms and buses, like PCI +or USB, or device type and device class drivers. Bus drivers implement these methods as appropriate for the hardware and the drivers using it; PCI works differently from USB, and so on. Not many people @@ -251,18 +252,29 @@ various phases always run after tasks have been frozen and before they are unfrozen. Furthermore, the *_noirq phases run at a time when IRQ handlers have been disabled (except for those marked with the IRQ_WAKEUP flag). -All phases use bus, type, or class callbacks (that is, methods defined in -dev->bus->pm, dev->type->pm, or dev->class->pm). These callbacks are mutually -exclusive, so if the device type provides a struct dev_pm_ops object pointed to -by its pm field (i.e. both dev->type and dev->type->pm are defined), the -callbacks included in that object (i.e. dev->type->pm) will be used. Otherwise, -if the class provides a struct dev_pm_ops object pointed to by its pm field -(i.e. both dev->class and dev->class->pm are defined), the PM core will use the -callbacks from that object (i.e. dev->class->pm). Finally, if the pm fields of -both the device type and class objects are NULL (or those objects do not exist), -the callbacks provided by the bus (that is, the callbacks from dev->bus->pm) -will be used (this allows device types to override callbacks provided by bus -types or classes if necessary). +All phases use PM domain, bus, type, or class callbacks (that is, methods +defined in dev->pm_domain->ops, dev->bus->pm, dev->type->pm, or dev->class->pm). +These callbacks are regarded by the PM core as mutually exclusive. Moreover, +PM domain callbacks always take precedence over bus, type and class callbacks, +while type callbacks take precedence over bus and class callbacks, and class +callbacks take precedence over bus callbacks. To be precise, the following +rules are used to determine which callback to execute in the given phase: + + 1. If dev->pm_domain is present, the PM core will attempt to execute the + callback included in dev->pm_domain->ops. If that callback is not + present, no action will be carried out for the given device. + + 2. Otherwise, if both dev->type and dev->type->pm are present, the callback + included in dev->type->pm will be executed. + + 3. Otherwise, if both dev->class and dev->class->pm are present, the + callback included in dev->class->pm will be executed. + + 4. Otherwise, if both dev->bus and dev->bus->pm are present, the callback + included in dev->bus->pm will be executed. + +This allows PM domains and device types to override callbacks provided by bus +types or device classes if necessary. These callbacks may in turn invoke device- or driver-specific methods stored in dev->driver->pm, but they don't have to. diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 5336149f831b..79b10a090c9f 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -44,17 +44,24 @@ struct dev_pm_ops { }; The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks -are executed by the PM core for either the power domain, or the device type -(if the device power domain's struct dev_pm_ops does not exist), or the class -(if the device power domain's and type's struct dev_pm_ops object does not -exist), or the bus type (if the device power domain's, type's and class' -struct dev_pm_ops objects do not exist) of the given device, so the priority -order of callbacks from high to low is that power domain callbacks, device -type callbacks, class callbacks and bus type callbacks, and the high priority -one will take precedence over low priority one. The bus type, device type and -class callbacks are referred to as subsystem-level callbacks in what follows, -and generally speaking, the power domain callbacks are used for representing -power domains within a SoC. +are executed by the PM core for the device's subsystem that may be either of +the following: + + 1. PM domain of the device, if the device's PM domain object, dev->pm_domain, + is present. + + 2. Device type of the device, if both dev->type and dev->type->pm are present. + + 3. Device class of the device, if both dev->class and dev->class->pm are + present. + + 4. Bus type of the device, if both dev->bus and dev->bus->pm are present. + +The PM core always checks which callback to use in the order given above, so the +priority order of callbacks from high to low is: PM domain, device type, class +and bus type. Moreover, the high-priority one will always take precedence over +a low-priority one. The PM domain, bus type, device type and class callbacks +are referred to as subsystem-level callbacks in what follows. By default, the callbacks are always invoked in process context with interrupts enabled. However, subsystems can use the pm_runtime_irq_safe() helper function -- cgit v1.2.3 From fa8ce723936460fcf7e49f508fd5dbd5125e39c4 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 23 Nov 2011 21:19:57 +0100 Subject: PM / Sleep: Correct inaccurate information in devices.txt The documentation file Documentation/power/devices.txt contains some information that isn't correct any more due to code modifications made after that file had been created (or updated last time). Fix this. Signed-off-by: Rafael J. Wysocki --- Documentation/power/devices.txt | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'Documentation') diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 4342acbeee10..ed3228884133 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -250,7 +250,7 @@ for every device before the next phase begins. Not all busses or classes support all these callbacks and not all drivers use all the callbacks. The various phases always run after tasks have been frozen and before they are unfrozen. Furthermore, the *_noirq phases run at a time when IRQ handlers have -been disabled (except for those marked with the IRQ_WAKEUP flag). +been disabled (except for those marked with the IRQF_NO_SUSPEND flag). All phases use PM domain, bus, type, or class callbacks (that is, methods defined in dev->pm_domain->ops, dev->bus->pm, dev->type->pm, or dev->class->pm). @@ -295,9 +295,8 @@ When the system goes into the standby or memory sleep state, the phases are: After the prepare callback method returns, no new children may be registered below the device. The method may also prepare the device or - driver in some way for the upcoming system power transition (for - example, by allocating additional memory required for this purpose), but - it should not put the device into a low-power state. + driver in some way for the upcoming system power transition, but it + should not put the device into a low-power state. 2. The suspend methods should quiesce the device to stop it from performing I/O. They also may save the device registers and put it into the -- cgit v1.2.3 From 907565921966260921e4c4581ed8985ef4cf9a67 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 23 Nov 2011 21:20:07 +0100 Subject: PM / Runtime: Make documentation follow the new behavior of irq_safe The runtime PM core code behavior related to the power.irq_safe device flag has changed recently and the documentation should be modified to reflect it. Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'Documentation') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 79b10a090c9f..c2ae8bf77d46 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -65,11 +65,12 @@ are referred to as subsystem-level callbacks in what follows. By default, the callbacks are always invoked in process context with interrupts enabled. However, subsystems can use the pm_runtime_irq_safe() helper function -to tell the PM core that a device's ->runtime_suspend() and ->runtime_resume() -callbacks should be invoked in atomic context with interrupts disabled. -This implies that these callback routines must not block or sleep, but it also -means that the synchronous helper functions listed at the end of Section 4 can -be used within an interrupt handler or in an atomic context. +to tell the PM core that their ->runtime_suspend(), ->runtime_resume() and +->runtime_idle() callbacks may be invoked in atomic context with interrupts +disabled for a given device. This implies that the callback routines in +question must not block or sleep, but it also means that the synchronous helper +functions listed at the end of Section 4 may be used for that device within an +interrupt handler or generally in an atomic context. The subsystem-level suspend callback is _entirely_ _responsible_ for handling the suspend of the device as appropriate, which may, but need not include -- cgit v1.2.3 From fafba48d4dd6fcbb1fd7ac4ab0ba22ef45b9796c Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 23 Nov 2011 21:20:15 +0100 Subject: PM / Sleep: Update documentation related to system wakeup The system wakeup section of Documentation/power/devices.txt is outdated, so make it agree with the current code. Signed-off-by: Rafael J. Wysocki --- Documentation/power/devices.txt | 60 ++++++++++++++++++++++++++--------------- 1 file changed, 38 insertions(+), 22 deletions(-) (limited to 'Documentation') diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index ed3228884133..3139fb505dce 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -140,41 +140,57 @@ sequencing in the driver model tree. /sys/devices/.../power/wakeup files ----------------------------------- -All devices in the driver model have two flags to control handling of wakeup -events (hardware signals that can force the device and/or system out of a low -power state). These flags are initialized by bus or device driver code using +All device objects in the driver model contain fields that control the handling +of system wakeup events (hardware signals that can force the system out of a +sleep state). These fields are initialized by bus or device driver code using device_set_wakeup_capable() and device_set_wakeup_enable(), defined in include/linux/pm_wakeup.h. -The "can_wakeup" flag just records whether the device (and its driver) can +The "power.can_wakeup" flag just records whether the device (and its driver) can physically support wakeup events. The device_set_wakeup_capable() routine -affects this flag. The "should_wakeup" flag controls whether the device should -try to use its wakeup mechanism. device_set_wakeup_enable() affects this flag; -for the most part drivers should not change its value. The initial value of -should_wakeup is supposed to be false for the majority of devices; the major -exceptions are power buttons, keyboards, and Ethernet adapters whose WoL -(wake-on-LAN) feature has been set up with ethtool. It should also default -to true for devices that don't generate wakeup requests on their own but merely -forward wakeup requests from one bus to another (like PCI bridges). +affects this flag. The "power.wakeup" field is a pointer to an object of type +struct wakeup_source used for controlling whether or not the device should use +its system wakeup mechanism and for notifying the PM core of system wakeup +events signaled by the device. This object is only present for wakeup-capable +devices (i.e. devices whose "can_wakeup" flags are set) and is created (or +removed) by device_set_wakeup_capable(). Whether or not a device is capable of issuing wakeup events is a hardware matter, and the kernel is responsible for keeping track of it. By contrast, whether or not a wakeup-capable device should issue wakeup events is a policy decision, and it is managed by user space through a sysfs attribute: the -power/wakeup file. User space can write the strings "enabled" or "disabled" to -set or clear the "should_wakeup" flag, respectively. This file is only present -for wakeup-capable devices (i.e. devices whose "can_wakeup" flags are set) -and is created (or removed) by device_set_wakeup_capable(). Reads from the -file will return the corresponding string. - -The device_may_wakeup() routine returns true only if both flags are set. +"power/wakeup" file. User space can write the strings "enabled" or "disabled" +to it to indicate whether or not, respectively, the device is supposed to signal +system wakeup. This file is only present if the "power.wakeup" object exists +for the given device and is created (or removed) along with that object, by +device_set_wakeup_capable(). Reads from the file will return the corresponding +string. + +The "power/wakeup" file is supposed to contain the "disabled" string initially +for the majority of devices; the major exceptions are power buttons, keyboards, +and Ethernet adapters whose WoL (wake-on-LAN) feature has been set up with +ethtool. It should also default to "enabled" for devices that don't generate +wakeup requests on their own but merely forward wakeup requests from one bus to +another (like PCI Express ports). + +The device_may_wakeup() routine returns true only if the "power.wakeup" object +exists and the corresponding "power/wakeup" file contains the string "enabled". This information is used by subsystems, like the PCI bus type code, to see whether or not to enable the devices' wakeup mechanisms. If device wakeup mechanisms are enabled or disabled directly by drivers, they also should use device_may_wakeup() to decide what to do during a system sleep transition. -However for runtime power management, wakeup events should be enabled whenever -the device and driver both support them, regardless of the should_wakeup flag. - +Device drivers, however, are not supposed to call device_set_wakeup_enable() +directly in any case. + +It ought to be noted that system wakeup is conceptually different from "remote +wakeup" used by runtime power management, although it may be supported by the +same physical mechanism. Remote wakeup is a feature allowing devices in +low-power states to trigger specific interrupts to signal conditions in which +they should be put into the full-power state. Those interrupts may or may not +be used to signal system wakeup events, depending on the hardware design. On +some systems it is impossible to trigger them from system sleep states. In any +case, remote wakeup should always be enabled for runtime power management for +all devices and drivers that support it. /sys/devices/.../power/control files ------------------------------------ -- cgit v1.2.3 From e43fce14088d9910b545c30c9a7127deb289d477 Mon Sep 17 00:00:00 2001 From: Pawel Moll Date: Tue, 8 Nov 2011 11:35:20 +0000 Subject: of: Add Silicon Image vendor prefix "sil" is the most commonly used abbreviation for Silicon Image products. Signed-off-by: Pawel Moll --- Documentation/devicetree/bindings/vendor-prefixes.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt index e8552782b440..874921e97802 100644 --- a/Documentation/devicetree/bindings/vendor-prefixes.txt +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -33,6 +33,7 @@ qcom Qualcomm, Inc. ramtron Ramtron International samsung Samsung Semiconductor schindler Schindler +sil Silicon Image simtek sirf SiRF Technology, Inc. stericsson ST-Ericsson -- cgit v1.2.3 From b52f75a595e8a70ee453bd6fb8023ee294f7a729 Mon Sep 17 00:00:00 2001 From: Arnd Hannemann Date: Wed, 16 Nov 2011 17:35:37 +0100 Subject: Fix URL of btrfs-progs git repository in docs The location of the btrfs-progs repository has been changed. This patch updates the documentation accordingly. Signed-off-by: Arnd Hannemann --- Documentation/filesystems/btrfs.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/filesystems/btrfs.txt b/Documentation/filesystems/btrfs.txt index 64087c34327f..7671352216f1 100644 --- a/Documentation/filesystems/btrfs.txt +++ b/Documentation/filesystems/btrfs.txt @@ -63,8 +63,8 @@ IRC network. Userspace tools for creating and manipulating Btrfs file systems are available from the git repository at the following location: - http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-progs-unstable.git - git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs-unstable.git + http://git.kernel.org/?p=linux/kernel/git/mason/btrfs-progs.git + git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-progs.git These include the following tools: -- cgit v1.2.3