1 /* SPDX-License-Identifier: GPL-2.0 */ 2 struct mcp23s08_platform_data { 3 /* For mcp23s08, up to 4 slaves (numbered 0..3) can share one SPI 4 * chipselect, each providing 1 gpio_chip instance with 8 gpios. 5 * For mpc23s17, up to 8 slaves (numbered 0..7) can share one SPI 6 * chipselect, each providing 1 gpio_chip (port A + port B) with 7 * 16 gpios. 8 */ 9 u32 spi_present_mask; 10 11 /* "base" is the number of the first GPIO or -1 for dynamic 12 * assignment. If there are gaps in chip addressing the GPIO 13 * numbers are sequential .. so for example if only slaves 0 14 * and 3 are present, their GPIOs range from base to base+15 15 * (or base+31 for s17 variant). 16 */ 17 unsigned base; 18 }; 19