Copyright	(c) 2016 Drew Hess
License	BSD3
Maintainer	Drew Hess <src@drewhess.com>
Stability	experimental
Portability	non-portable
Safe Haskell	Safe
Language	Haskell2010

System.GPIO.Linux.Sysfs.Types

Contents

sysfs-specific types
Exceptions

Description

Types used by the various Linux sysfs GPIO implementations.

`sysfs`-specific types

data SysfsEdge Source #

Linux GPIO pins that can be configured to generate inputs have an edge attribute in the sysfs GPIO filesystem. This type represents the values that the edge attribute can take.

Note that in Linux sysfs GPIO, the signal edge referred to by the edge attribute refers to the signal's logical value; i.e., it takes into account the value of the pin's active_low attribute.

This type is isomorphic to the PinInterruptMode type. See toPinInterruptMode and toSysfsEdge.

Constructors

None	Interrupts disabled
Rising	Interrupt on the (logical) signal's rising edge
Falling	Interrupt on the (logical) signal's falling edge
Both	Interrupt on any change to the signal level

Instances

Bounded SysfsEdge Source #
Methods minBound :: SysfsEdge # maxBound :: SysfsEdge #
Enum SysfsEdge Source #
Methods succ :: SysfsEdge -> SysfsEdge # pred :: SysfsEdge -> SysfsEdge # toEnum :: Int -> SysfsEdge # fromEnum :: SysfsEdge -> Int # enumFrom :: SysfsEdge -> [SysfsEdge] # enumFromThen :: SysfsEdge -> SysfsEdge -> [SysfsEdge] # enumFromTo :: SysfsEdge -> SysfsEdge -> [SysfsEdge] # enumFromThenTo :: SysfsEdge -> SysfsEdge -> SysfsEdge -> [SysfsEdge] #
Eq SysfsEdge Source #
Methods (==) :: SysfsEdge -> SysfsEdge -> Bool # (/=) :: SysfsEdge -> SysfsEdge -> Bool #
Data SysfsEdge Source #
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> SysfsEdge -> c SysfsEdge # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c SysfsEdge # toConstr :: SysfsEdge -> Constr # dataTypeOf :: SysfsEdge -> DataType # dataCast1 :: Typeable (* -> ) t => (forall d. Data d => c (t d)) -> Maybe (c SysfsEdge) # dataCast2 :: Typeable ( -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c SysfsEdge) # gmapT :: (forall b. Data b => b -> b) -> SysfsEdge -> SysfsEdge # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> SysfsEdge -> r # gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> SysfsEdge -> r # gmapQ :: (forall d. Data d => d -> u) -> SysfsEdge -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> SysfsEdge -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> SysfsEdge -> m SysfsEdge # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> SysfsEdge -> m SysfsEdge # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> SysfsEdge -> m SysfsEdge #
Ord SysfsEdge Source #
Methods compare :: SysfsEdge -> SysfsEdge -> Ordering # (<) :: SysfsEdge -> SysfsEdge -> Bool # (<=) :: SysfsEdge -> SysfsEdge -> Bool # (>) :: SysfsEdge -> SysfsEdge -> Bool # (>=) :: SysfsEdge -> SysfsEdge -> Bool # max :: SysfsEdge -> SysfsEdge -> SysfsEdge # min :: SysfsEdge -> SysfsEdge -> SysfsEdge #
Read SysfsEdge Source #
Methods readsPrec :: Int -> ReadS SysfsEdge # readList :: ReadS [SysfsEdge] # readPrec :: ReadPrec SysfsEdge # readListPrec :: ReadPrec [SysfsEdge] #
Show SysfsEdge Source #
Methods showsPrec :: Int -> SysfsEdge -> ShowS # show :: SysfsEdge -> String # showList :: [SysfsEdge] -> ShowS #
Generic SysfsEdge Source #
Associated Types type Rep SysfsEdge :: * -> * # Methods from :: SysfsEdge -> Rep SysfsEdge x # to :: Rep SysfsEdge x -> SysfsEdge #
Arbitrary SysfsEdge Source #
Methods arbitrary :: Gen SysfsEdge # shrink :: SysfsEdge -> [SysfsEdge] #
type Rep SysfsEdge Source #
type Rep SysfsEdge = D1 (MetaData "SysfsEdge" "System.GPIO.Linux.Sysfs.Types" "hpio-0.8.0.4-GJzojGXJbp82GVXKhRl2KX" False) ((:+:) ((:+:) (C1 (MetaCons "None" PrefixI False) U1) (C1 (MetaCons "Rising" PrefixI False) U1)) ((:+:) (C1 (MetaCons "Falling" PrefixI False) U1) (C1 (MetaCons "Both" PrefixI False) U1)))

toPinInterruptMode :: SysfsEdge -> PinInterruptMode Source #

Convert a SysfsEdge value to its equivalent PinInterruptMode value.

>>> toPinInterruptMode None
Disabled
>>> toPinInterruptMode Rising
RisingEdge
>>> toPinInterruptMode Falling
FallingEdge
>>> toPinInterruptMode Both
Level

toSysfsEdge :: PinInterruptMode -> SysfsEdge Source #

Convert a PinInterruptMode value to its equivalent SysfsEdge value.

>>> toSysfsEdge Disabled
None
>>> toSysfsEdge RisingEdge
Rising
>>> toSysfsEdge FallingEdge
Falling
>>> toSysfsEdge Level
Both

Exceptions

data SysfsException Source #

Exceptions that can be thrown by sysfs computations (in addition to standard IOError exceptions, of course).

The UnexpectedX values are truly exceptional and mean that, while the sysfs attribute for the given pin exists, the contents of the attribute do not match any expected value for that attribute, which probably means that the package is incompatible with the sysfs filesystem due to a kernel-level change.

Constructors

SysfsNotPresent	The `sysfs` filesystem does not exist
SysfsError	Something in the `sysfs` filesystem does not behave as expected (could indicate a change in `sysfs` behavior that the package does not expect)
SysfsPermissionDenied	The `sysfs` operation is not permitted due to insufficient permissions
PermissionDenied Pin	The operation on the specified pin is not permitted, either due to insufficient permissions, or because the pin's attribute cannot be modified (e.g., trying to write to a pin that's configured for input)
InvalidOperation Pin	The operation is invalid for the specified pin, or in the specified pin's current configuration
AlreadyExported Pin	The pin has already been exported
InvalidPin Pin	The specified pin does not exist
NotExported Pin	The pin has been un-exported or does not exist
UnsupportedInputMode PinInputMode Pin	The pin does not support the specified input mode
UnsupportedOutputMode PinOutputMode Pin	The pin does not support the specified output mode
NoDirectionAttribute Pin	The pin does not have a `direction` attribute
NoEdgeAttribute Pin	The pin does not have an `edge` attribute
UnexpectedDirection Pin String	An unexpected value was read from the pin's `direction` attribute
UnexpectedValue Pin String	An unexpected value was read from the pin's `value` attribute
UnexpectedEdge Pin String	An unexpected value was read from the pin's `edge` attribute
UnexpectedActiveLow Pin String	An unexpected value was read from the pin's `active_low` attribute
UnexpectedContents FilePath String	An unexpected value was read from the specified file
InternalError String	An internal error has occurred in the interpreter, something which should "never happen" and should be reported to the package maintainer

Instances

Eq SysfsException Source #
Methods (==) :: SysfsException -> SysfsException -> Bool # (/=) :: SysfsException -> SysfsException -> Bool #
Show SysfsException Source #
Methods showsPrec :: Int -> SysfsException -> ShowS # show :: SysfsException -> String # showList :: [SysfsException] -> ShowS #
Exception SysfsException Source #
Methods toException :: SysfsException -> SomeException # fromException :: SomeException -> Maybe SysfsException # displayException :: SysfsException -> String #

sysfs-specific types

Exceptions

`sysfs`-specific types