diff options
Diffstat (limited to 'kernel/include/linux/spi/mcp23s08.h')
-rw-r--r-- | kernel/include/linux/spi/mcp23s08.h | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/kernel/include/linux/spi/mcp23s08.h b/kernel/include/linux/spi/mcp23s08.h new file mode 100644 index 000000000..aa07d7b32 --- /dev/null +++ b/kernel/include/linux/spi/mcp23s08.h @@ -0,0 +1,43 @@ + +/* FIXME driver should be able to handle IRQs... */ + +struct mcp23s08_chip_info { + bool is_present; /* true if populated */ + unsigned pullups; /* BIT(x) means enable pullup x */ +}; + +struct mcp23s08_platform_data { + /* For mcp23s08, up to 4 slaves (numbered 0..3) can share one SPI + * chipselect, each providing 1 gpio_chip instance with 8 gpios. + * For mpc23s17, up to 8 slaves (numbered 0..7) can share one SPI + * chipselect, each providing 1 gpio_chip (port A + port B) with + * 16 gpios. + */ + struct mcp23s08_chip_info chip[8]; + + /* "base" is the number of the first GPIO. Dynamic assignment is + * not currently supported, and even if there are gaps in chip + * addressing the GPIO numbers are sequential .. so for example + * if only slaves 0 and 3 are present, their GPIOs range from + * base to base+15 (or base+31 for s17 variant). + */ + unsigned base; + /* Marks the device as a interrupt controller. + * NOTE: The interrupt functionality is only supported for i2c + * versions of the chips. The spi chips can also do the interrupts, + * but this is not supported by the linux driver yet. + */ + bool irq_controller; + + /* Sets the mirror flag in the IOCON register. Devices + * with two interrupt outputs (these are the devices ending with 17 and + * those that have 16 IOs) have two IO banks: IO 0-7 form bank 1 and + * IO 8-15 are bank 2. These chips have two different interrupt outputs: + * One for bank 1 and another for bank 2. If irq-mirror is set, both + * interrupts are generated regardless of the bank that an input change + * occurred on. If it is not set, the interrupt are only generated for + * the bank they belong to. + * On devices with only one interrupt output this property is useless. + */ + bool mirror; +}; |