// SPDX-License-Identifier: GPL-2.0+ /* * (C) Copyright 2011 * Dirk Eibach, Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc */ /* * Driver for NXP's pca9698 40 bit I2C gpio expander */ #include <common.h> #include <i2c.h> #include <malloc.h> #include <linux/errno.h> #include <pca9698.h> /* * The pca9698 registers */ #define PCA9698_REG_INPUT 0x00 #define PCA9698_REG_OUTPUT 0x08 #define PCA9698_REG_POLARITY 0x10 #define PCA9698_REG_CONFIG 0x18 #define PCA9698_BUFFER_SIZE 5 #define PCA9698_GPIO_COUNT 40 static int pca9698_read40(u8 addr, u8 offset, u8 *buffer) { u8 command = offset | 0x80; /* autoincrement */ return i2c_read(addr, command, 1, buffer, PCA9698_BUFFER_SIZE); } static int pca9698_write40(u8 addr, u8 offset, u8 *buffer) { u8 command = offset | 0x80; /* autoincrement */ return i2c_write(addr, command, 1, buffer, PCA9698_BUFFER_SIZE); } static void pca9698_set_bit(unsigned gpio, u8 *buffer, unsigned value) { unsigned byte = gpio / 8; unsigned bit = gpio % 8; if (value) buffer[byte] |= (1 << bit); else buffer[byte] &= ~(1 << bit); } int pca9698_request(unsigned gpio, const char *label) { if (gpio >= PCA9698_GPIO_COUNT) return -EINVAL; return 0; } void pca9698_free(unsigned gpio) { } int pca9698_direction_input(u8 addr, unsigned gpio) { u8 data[PCA9698_BUFFER_SIZE]; int res; res = pca9698_read40(addr, PCA9698_REG_CONFIG, data); if (res) return res; pca9698_set_bit(gpio, data, 1); return pca9698_write40(addr, PCA9698_REG_CONFIG, data); } int pca9698_direction_output(u8 addr, unsigned gpio, int value) { u8 data[PCA9698_BUFFER_SIZE]; int res; res = pca9698_set_value(addr, gpio, value); if (res) return res; res = pca9698_read40(addr, PCA9698_REG_CONFIG, data); if (res) return res; pca9698_set_bit(gpio, data, 0); return pca9698_write40(addr, PCA9698_REG_CONFIG, data); } int pca9698_get_value(u8 addr, unsigned gpio) { unsigned config_byte = gpio / 8; unsigned config_bit = gpio % 8; unsigned value; u8 data[PCA9698_BUFFER_SIZE]; int res; res = pca9698_read40(addr, PCA9698_REG_INPUT, data); if (res) return -1; value = data[config_byte] & (1 << config_bit); return !!value; } int pca9698_set_value(u8 addr, unsigned gpio, int value) { u8 data[PCA9698_BUFFER_SIZE]; int res; res = pca9698_read40(addr, PCA9698_REG_OUTPUT, data); if (res) return res; pca9698_set_bit(gpio, data, value); return pca9698_write40(addr, PCA9698_REG_OUTPUT, data); }