zephyr/drivers/pinmux/pinmux_quark_mcu.h
Kumar Gala ccad5bf3e3 drivers: convert to using newly introduced integer sized types
Convert code to use u{8,16,32,64}_t and s{8,16,32,64}_t instead of C99
integer types.

Jira: ZEP-2051

Change-Id: I08f51e2bfd475f6245771c1bd2df7ffc744c48c4
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2017-04-21 10:06:48 -05:00

64 lines
1.9 KiB
C

/* pinmux_quark_mcu.h - pinmux operation for generic Quark MCU boards */
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#define PINMUX_PULLUP_OFFSET 0x00
#define PINMUX_SLEW_OFFSET 0x10
#define PINMUX_INPUT_OFFSET 0x20
#define PINMUX_SELECT_OFFSET 0x30
#define PINMUX_SELECT_REGISTER(base, reg_offset) \
(base + PINMUX_SELECT_OFFSET + (reg_offset << 2))
/*
* A little decyphering of what is going on here:
*
* Each pinmux register rperesents a bank of 16 pins, 2 bits per pin for a total
* of four possible settings per pin.
*
* The first argument to the macro is name of the u32_t's that is being used
* to contain the bit patterns for all the configuration registers. The pin
* number divided by 16 selects the correct register bank based on the pin
* number.
*
* The pin number % 16 * 2 selects the position within the register bank for the
* bits controlling the pin.
*
* All but the lower two bits of the config values are masked off to ensure
* that we don't inadvertently affect other pins in the register bank.
*/
#define PIN_CONFIG(A, _pin, _func) \
(A[((_pin) / 16)] |= ((0x3 & (_func)) << (((_pin) % 16) * 2)))
static inline int _quark_mcu_set_mux(u32_t base, u32_t pin, u8_t func)
{
/*
* the registers are 32-bit wide, but each pin requires 1 bit
* to set the input enable bit.
*/
u32_t register_offset = (pin / 32) * 4;
/*
* Now figure out what is the full address for the register
* we are looking for. Add the base register to the register_mask
*/
volatile u32_t *mux_register = (u32_t *)(base + register_offset);
/*
* Finally grab the pin offset within the register
*/
u32_t pin_offset = pin % 32;
/*
* MAGIC NUMBER: 0x1 is used as the pullup is a single bit in a
* 32-bit register.
*/
(*(mux_register)) = ((*(mux_register)) & ~(0x1 << pin_offset)) |
((func & 0x01) << pin_offset);
return 0;
}