115fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell#ifndef __LINUX_PCF857X_H 215fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell#define __LINUX_PCF857X_H 315fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell 415fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell/** 515fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * struct pcf857x_platform_data - data to set up pcf857x driver 615fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * @gpio_base: number of the chip's first GPIO 715fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * @n_latch: optional bit-inverse of initial register value; if 815fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * you leave this initialized to zero the driver will act 915fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * like the chip was just reset 1015fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * @setup: optional callback issued once the GPIOs are valid 1115fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * @teardown: optional callback issued before the GPIOs are invalidated 1215fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * @context: optional parameter passed to setup() and teardown() 1315fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * 1415fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * In addition to the I2C_BOARD_INFO() state appropriate to each chip, 15eb8a79080984eb9819406a55e4dd17043c380a09Jean Delvare * the i2c_board_info used with the pcf875x driver must provide its 1615fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * platform_data (pointer to one of these structures) with at least 1715fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * the gpio_base value initialized. 1815fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * 1915fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * The @setup callback may be used with the kind of board-specific glue 2015fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * which hands the (now-valid) GPIOs to other drivers, or which puts 2115fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * devices in their initial states using these GPIOs. 2215fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * 2315fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * These GPIO chips are only "quasi-bidirectional"; read the chip specs 2415fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * to understand the behavior. They don't have separate registers to 2515fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * record which pins are used for input or output, record which output 2615fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * values are driven, or provide access to input values. That must be 2715fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * inferred by reading the chip's value and knowing the last value written 2815fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * to it. If you leave n_latch initialized to zero, that last written 2915fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell * value is presumed to be all ones (as if the chip were just reset). 3015fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell */ 3115fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownellstruct pcf857x_platform_data { 3215fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell unsigned gpio_base; 3315fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell unsigned n_latch; 3415fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell 3515fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell int (*setup)(struct i2c_client *client, 3615fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell int gpio, unsigned ngpio, 3715fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell void *context); 3815fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell int (*teardown)(struct i2c_client *client, 3915fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell int gpio, unsigned ngpio, 4015fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell void *context); 4115fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell void *context; 4215fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell}; 4315fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell 4415fae37d9f5f21571a9618d8353164b6ddfea6f6David Brownell#endif /* __LINUX_PCF857X_H */ 45