diff options
Diffstat (limited to 'drivers/tty/serial/sc16is7xx_spi.c')
| -rw-r--r-- | drivers/tty/serial/sc16is7xx_spi.c | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/drivers/tty/serial/sc16is7xx_spi.c b/drivers/tty/serial/sc16is7xx_spi.c new file mode 100644 index 00000000000000..73df36f8a7fd86 --- /dev/null +++ b/drivers/tty/serial/sc16is7xx_spi.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* SC16IS7xx SPI interface driver */ + +#include <linux/dev_printk.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/spi/spi.h> +#include <linux/string.h> +#include <linux/units.h> + +#include "sc16is7xx.h" + +/* SPI definitions */ +#define SC16IS7XX_SPI_READ_BIT BIT(7) + +static int sc16is7xx_spi_probe(struct spi_device *spi) +{ + const struct sc16is7xx_devtype *devtype; + struct regmap *regmaps[SC16IS7XX_MAX_PORTS]; + struct regmap_config regcfg; + unsigned int i; + int ret; + + /* Setup SPI bus */ + spi->bits_per_word = 8; + /* For all variants, only mode 0 is supported */ + if ((spi->mode & SPI_MODE_X_MASK) != SPI_MODE_0) + return dev_err_probe(&spi->dev, -EINVAL, "Unsupported SPI mode\n"); + + spi->mode = spi->mode ? : SPI_MODE_0; + spi->max_speed_hz = spi->max_speed_hz ? : 4 * HZ_PER_MHZ; + ret = spi_setup(spi); + if (ret) + return ret; + + devtype = spi_get_device_match_data(spi); + if (!devtype) + return dev_err_probe(&spi->dev, -ENODEV, "Failed to match device\n"); + + memcpy(®cfg, &sc16is7xx_regcfg, sizeof(struct regmap_config)); + + for (i = 0; i < devtype->nr_uart; i++) { + regcfg.name = sc16is7xx_regmap_name(i); + /* + * If read_flag_mask is 0, the regmap code sets it to a default + * of 0x80. Since we specify our own mask, we must add the READ + * bit ourselves: + */ + regcfg.read_flag_mask = sc16is7xx_regmap_port_mask(i) | + SC16IS7XX_SPI_READ_BIT; + regcfg.write_flag_mask = sc16is7xx_regmap_port_mask(i); + regmaps[i] = devm_regmap_init_spi(spi, ®cfg); + } + + return sc16is7xx_probe(&spi->dev, devtype, regmaps, spi->irq); +} + +static void sc16is7xx_spi_remove(struct spi_device *spi) +{ + sc16is7xx_remove(&spi->dev); +} + +static const struct spi_device_id sc16is7xx_spi_id_table[] = { + { "sc16is74x", (kernel_ulong_t)&sc16is74x_devtype, }, + { "sc16is740", (kernel_ulong_t)&sc16is74x_devtype, }, + { "sc16is741", (kernel_ulong_t)&sc16is74x_devtype, }, + { "sc16is750", (kernel_ulong_t)&sc16is750_devtype, }, + { "sc16is752", (kernel_ulong_t)&sc16is752_devtype, }, + { "sc16is760", (kernel_ulong_t)&sc16is760_devtype, }, + { "sc16is762", (kernel_ulong_t)&sc16is762_devtype, }, + { } +}; +MODULE_DEVICE_TABLE(spi, sc16is7xx_spi_id_table); + +static struct spi_driver sc16is7xx_spi_driver = { + .driver = { + .name = SC16IS7XX_NAME, + .of_match_table = sc16is7xx_dt_ids, + }, + .probe = sc16is7xx_spi_probe, + .remove = sc16is7xx_spi_remove, + .id_table = sc16is7xx_spi_id_table, +}; + +module_spi_driver(sc16is7xx_spi_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("SC16IS7xx SPI interface driver"); +MODULE_IMPORT_NS(SERIAL_NXP_SC16IS7XX); |