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Server : Apache/2.4.18 (Ubuntu) System : Linux canvaswebdesign 3.13.0-71-generic #114-Ubuntu SMP Tue Dec 1 02:34:22 UTC 2015 x86_64 User : oppastar ( 1041) PHP Version : 7.0.33-0ubuntu0.16.04.15 Disable Function : pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority, Directory : /proc/self/root/lib/modules/4.4.0-119-generic/build/include/linux/spi/ |
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#ifndef __LINUX_SPI_GPIO_H
#define __LINUX_SPI_GPIO_H
/*
* For each bitbanged SPI bus, set up a platform_device node with:
* - name "spi_gpio"
* - id the same as the SPI bus number it implements
* - dev.platform data pointing to a struct spi_gpio_platform_data
*
* Or, see the driver code for information about speedups that are
* possible on platforms that support inlined access for GPIOs (no
* spi_gpio_platform_data is used).
*
* Use spi_board_info with these busses in the usual way, being sure
* that the controller_data being the GPIO used for each device's
* chipselect:
*
* static struct spi_board_info ... [] = {
* ...
* // this slave uses GPIO 42 for its chipselect
* .controller_data = (void *) 42,
* ...
* // this one uses GPIO 86 for its chipselect
* .controller_data = (void *) 86,
* ...
* };
*
* If chipselect is not used (there's only one device on the bus), assign
* SPI_GPIO_NO_CHIPSELECT to the controller_data:
* .controller_data = (void *) SPI_GPIO_NO_CHIPSELECT;
*
* If the MISO or MOSI pin is not available then it should be set to
* SPI_GPIO_NO_MISO or SPI_GPIO_NO_MOSI.
*
* If the bitbanged bus is later switched to a "native" controller,
* that platform_device and controller_data should be removed.
*/
#define SPI_GPIO_NO_CHIPSELECT ((unsigned long)-1l)
#define SPI_GPIO_NO_MISO ((unsigned long)-1l)
#define SPI_GPIO_NO_MOSI ((unsigned long)-1l)
/**
* struct spi_gpio_platform_data - parameter for bitbanged SPI master
* @sck: number of the GPIO used for clock output
* @mosi: number of the GPIO used for Master Output, Slave In (MOSI) data
* @miso: number of the GPIO used for Master Input, Slave Output (MISO) data
* @num_chipselect: how many slaves to allow
*
* All GPIO signals used with the SPI bus managed through this driver
* (chipselects, MOSI, MISO, SCK) must be configured as GPIOs, instead
* of some alternate function.
*
* It can be convenient to use this driver with pins that have alternate
* functions associated with a "native" SPI controller if a driver for that
* controller is not available, or is missing important functionality.
*
* On platforms which can do so, configure MISO with a weak pullup unless
* there's an external pullup on that signal. That saves power by avoiding
* floating signals. (A weak pulldown would save power too, but many
* drivers expect to see all-ones data as the no slave "response".)
*/
struct spi_gpio_platform_data {
unsigned sck;
unsigned long mosi;
unsigned long miso;
u16 num_chipselect;
};
#endif /* __LINUX_SPI_GPIO_H */