diff options
Diffstat (limited to 'drivers/gpio/sx151x.c')
| -rw-r--r-- | drivers/gpio/sx151x.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/drivers/gpio/sx151x.c b/drivers/gpio/sx151x.c new file mode 100644 index 0000000..167cf40 --- /dev/null +++ b/drivers/gpio/sx151x.c @@ -0,0 +1,242 @@ +/* + * (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, ®, &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, ®, &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 */ |