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path: root/drivers/gpio/gpio-ws16c48.c
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2017-03-16gpio: ws16c48: make use of raw_spinlock variantsJulia Cartwright
The ws16c48 gpio driver currently implements an irq_chip for handling interrupts; due to how irq_chip handling is done, it's necessary for the irq_chip methods to be invoked from hardirq context, even on a a real-time kernel. Because the spinlock_t type becomes a "sleeping" spinlock w/ RT kernels, it is not suitable to be used with irq_chips. A quick audit of the operations under the lock reveal that they do only minimal, bounded work, and are therefore safe to do under a raw spinlock. Signed-off-by: Julia Cartwright <julia@ni.com> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-02-01gpio: ws16c48: Add support for GPIO namesWilliam Breathitt Gray
This patch sets the gpio_chip names option with an array of GPIO line names that match the manual documentation for the WinSystems WS16C48. This should make it easier for users to identify which GPIO line corresponds to a respective GPIO pin on the device. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-02-01gpio: ws16c48: Remove unnecessary driver_data setWilliam Breathitt Gray
Setting driver_data was necessary to access private data in the ws16c48_remove function. Now that the ws16c48_remove function is gone, driver_data is no longer used. This patch removes the relevant code. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26gpio: ws16c48: Utilize devm_ functions in driver probe callbackWilliam Breathitt Gray
The devm_ resource manager functions allow memory to be automatically released when a device is unbound. This patch takes advantage of the resource manager functions and replaces the gpiochip_add_data call and request_irq call with the devm_gpiochip_add_data call and devm_request_irq call respectively. In addition, the ws16c48_remove function has been removed as no longer necessary due to the use of the relevant devm_ resource manager functions. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26gpio: ws16c48: Add set_multiple callback function supportWilliam Breathitt Gray
The WinSystems WS16C48 provides registers where 8 lines of GPIO may be set at a time. This patch add support for the set_multiple callback function, thus allowing multiple GPIO output lines to be set more efficiently in groups. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-05-02gpio: ws16c48: Utilize the ISA bus driverWilliam Breathitt Gray
The WinSystems WS16C48 communicates via the ISA bus. As such, it is more appropriate to use the ISA bus driver over the platform driver to control the WinSystems WS16C48 GPIO driver. This patch also adds support for multiple devices via the base and irq module array parameters. Each element of the base array corresponds to a discrete device; each element of the irq array corresponds to the respective device addressed in the respective base array element. Acked-by: Linus Walleij <linus.walleij@linaro.org> Cc: Alexandre Courbot <gnurou@gmail.com> Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-16gpio: ws16c48: Use devm_request_regionWilliam Breathitt Gray
By the time request_region is called in the WinSystems WS16C48 GPIO driver, a corresponding device structure has already been allocated. The devm_request_region function should be used to help simplify the cleanup code and reduce the possible points of failure. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16gpio: misc: Pass correct license string to MODULE_LICENSEWilliam Breathitt Gray
The GPIO driver copyright boilerplate lacks the "or later" verbiage regarding GPL compliant distribution. The MODULE_LICENSE string should reflect the actual copyright license terms used. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-01-28gpio: Add GPIO support for the WinSystems WS16C48William Breathitt Gray
The WinSystems WS16C48 device provides 48 lines of digital I/O. In addition, the first 24 lines may be used for interrupt-handled edge detection; rising edge detection and falling edge detection are supported. This driver provides GPIO and IRQ support for these 48 channels of digital I/O. The base port address for the device may be configured via the ws16c48_base module parameter. The interrupt line number for the device may be configured via the ws16c48_irq module parameter. Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>