u-boot/drivers/gpio/sx151x.c
Viktar Palstsiuk 7d9ec6a0af Add support for SX151x SPI GPIO Expanders
Signed-off-by: Viktar Palstsiuk <viktar.palstsiuk@promwad.com>
2013-11-08 09:39:13 -05:00

242 lines
5.1 KiB
C

/*
* (C) Copyright 2013
* Viktar Palstsiuk, Promwad, viktar.palstsiuk@promwad.com
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* Driver for Semtech SX151x SPI GPIO Expanders
*/
#include <common.h>
#include <spi.h>
#include <sx151x.h>
#ifndef CONFIG_SX151X_SPI_BUS
#define CONFIG_SX151X_SPI_BUS 0
#endif
/*
* The SX151x registers
*/
#ifdef CONFIG_SX151X_GPIO_COUNT_8
/* 8bit: SX1511 */
#define SX151X_REG_DIR 0x07
#define SX151X_REG_DATA 0x08
#else
/* 16bit: SX1512 */
#define SX151X_REG_DIR 0x0F
#define SX151X_REG_DATA 0x11
#endif
#define SX151X_REG_RESET 0x7D
static int sx151x_spi_write(int chip, unsigned char reg, unsigned char val)
{
struct spi_slave *slave;
unsigned char buf[2];
int ret;
slave = spi_setup_slave(CONFIG_SX151X_SPI_BUS, chip, 1000000,
SPI_MODE_0);
if (!slave)
return 0;
spi_claim_bus(slave);
buf[0] = reg;
buf[1] = val;
ret = spi_xfer(slave, 16, buf, NULL, SPI_XFER_BEGIN | SPI_XFER_END);
if (ret < 0)
printf("spi%d.%d write fail: can't write %02x to %02x: %d\n",
CONFIG_SX151X_SPI_BUS, chip, val, reg, ret);
else
printf("spi%d.%d write 0x%02x to register 0x%02x\n",
CONFIG_SX151X_SPI_BUS, chip, val, reg);
spi_release_bus(slave);
spi_free_slave(slave);
return ret;
}
static int sx151x_spi_read(int chip, unsigned char reg)
{
struct spi_slave *slave;
int ret;
slave = spi_setup_slave(CONFIG_SX151X_SPI_BUS, chip, 1000000,
SPI_MODE_0);
if (!slave)
return 0;
spi_claim_bus(slave);
ret = spi_w8r8(slave, reg | 0x80);
if (ret < 0)
printf("spi%d.%d read fail: can't read %02x: %d\n",
CONFIG_SX151X_SPI_BUS, chip, reg, ret);
else
printf("spi%d.%d read register 0x%02x: 0x%02x\n",
CONFIG_SX151X_SPI_BUS, chip, reg, ret);
spi_release_bus(slave);
spi_free_slave(slave);
return ret;
}
static inline void sx151x_find_cfg(int gpio, unsigned char *reg, unsigned char *mask)
{
*reg -= gpio / 8;
*mask = 1 << (gpio % 8);
}
static int sx151x_write_cfg(int chip, unsigned char gpio, unsigned char reg, int val)
{
unsigned char mask;
unsigned char data;
int ret;
sx151x_find_cfg(gpio, &reg, &mask);
ret = sx151x_spi_read(chip, reg);
if (ret < 0)
return ret;
else
data = ret;
data &= ~mask;
data |= (val << (gpio % 8)) & mask;
return sx151x_spi_write(chip, reg, data);
}
int sx151x_get_value(int chip, int gpio)
{
unsigned char reg = SX151X_REG_DATA;
unsigned char mask;
int ret;
sx151x_find_cfg(gpio, &reg, &mask);
ret = sx151x_spi_read(chip, reg);
if (ret >= 0)
ret = (ret & mask) != 0 ? 1 : 0;
return ret;
}
int sx151x_set_value(int chip, int gpio, int val)
{
return sx151x_write_cfg(chip, gpio, SX151X_REG_DATA, (val ? 1 : 0));
}
int sx151x_direction_input(int chip, int gpio)
{
return sx151x_write_cfg(chip, gpio, SX151X_REG_DIR, 1);
}
int sx151x_direction_output(int chip, int gpio)
{
return sx151x_write_cfg(chip, gpio, SX151X_REG_DIR, 0);
}
int sx151x_reset(int chip)
{
int err;
err = sx151x_spi_write(chip, SX151X_REG_RESET, 0x12);
if (err < 0)
return err;
err = sx151x_spi_write(chip, SX151X_REG_RESET, 0x34);
return err;
}
#ifdef CONFIG_CMD_SX151X
int do_sx151x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int ret = CMD_RET_USAGE, chip = 0, gpio = 0, val = 0;
if (argc < 3)
return CMD_RET_USAGE;
/* arg2 used as chip number */
chip = simple_strtoul(argv[2], NULL, 10);
if (strcmp(argv[1], "reset") == 0) {
ret = sx151x_reset(chip);
if (!ret) {
printf("Device at spi%d.%d was reset\n",
CONFIG_SX151X_SPI_BUS, chip);
}
return ret;
}
if (argc < 4)
return CMD_RET_USAGE;
/* arg3 used as gpio number */
gpio = simple_strtoul(argv[3], NULL, 10);
if (strcmp(argv[1], "get") == 0) {
ret = sx151x_get_value(chip, gpio);
if (ret < 0)
printf("Failed to get value at spi%d.%d gpio %d\n",
CONFIG_SX151X_SPI_BUS, chip, gpio);
else {
printf("Value at spi%d.%d gpio %d is %d\n",
CONFIG_SX151X_SPI_BUS, chip, gpio, ret);
ret = 0;
}
return ret;
}
if (argc < 5)
return CMD_RET_USAGE;
/* arg4 used as value or direction */
val = simple_strtoul(argv[4], NULL, 10);
if (strcmp(argv[1], "set") == 0) {
ret = sx151x_set_value(chip, gpio, val);
if (ret < 0)
printf("Failed to set value at spi%d.%d gpio %d\n",
CONFIG_SX151X_SPI_BUS, chip, gpio);
else
printf("New value at spi%d.%d gpio %d is %d\n",
CONFIG_SX151X_SPI_BUS, chip, gpio, val);
return ret;
} else if (strcmp(argv[1], "dir") == 0) {
if (val == 0)
ret = sx151x_direction_output(chip, gpio);
else
ret = sx151x_direction_input(chip, gpio);
if (ret < 0)
printf("Failed to set direction of spi%d.%d gpio %d\n",
CONFIG_SX151X_SPI_BUS, chip, gpio);
else
printf("New direction of spi%d.%d gpio %d is %d\n",
CONFIG_SX151X_SPI_BUS, chip, gpio, val);
return ret;
}
printf("Please see usage\n");
return ret;
}
U_BOOT_CMD(
sx151x, 5, 1, do_sx151x,
"sx151x gpio access",
"dir chip gpio 0|1\n"
" - set gpio direction (0 for output, 1 for input)\n"
"sx151x get chip gpio\n"
" - get gpio value\n"
"sx151x set chip gpio 0|1\n"
" - set gpio value\n"
"sx151x reset chip\n"
" - reset chip"
);
#endif /* CONFIG_CMD_SX151X */