diff options
| -rw-r--r-- | MAINTAINERS | 1 | ||||
| -rw-r--r-- | drivers/gpio/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/gpio/Makefile | 1 | ||||
| -rw-r--r-- | drivers/gpio/gpio-moxtet.c | 179 |
4 files changed, 190 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 1869e83f514a..a71ab252ad7e 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1635,6 +1635,7 @@ F: Documentation/ABI/testing/sysfs-bus-moxtet-devices F: Documentation/devicetree/bindings/bus/moxtet.txt F: include/linux/moxtet.h F: drivers/bus/moxtet.c +F: drivers/gpio/gpio-moxtet.c ARM/EBSA110 MACHINE SUPPORT M: Russell King <linux@armlinux.org.uk> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index bb13c266c329..eef4886a3bc3 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -1445,6 +1445,15 @@ config GPIO_XRA1403 help GPIO driver for EXAR XRA1403 16-bit SPI-based GPIO expander. +config GPIO_MOXTET + tristate "Turris Mox Moxtet bus GPIO expander" + depends on MOXTET + help + Say yes here if you are building for the Turris Mox router. + This is the driver needed for configuring the GPIOs via the Moxtet + bus. For example the Mox module with SFP cage needs this driver + so that phylink can use corresponding GPIOs. + endmenu menu "USB GPIO expanders" diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index a4e91175c708..2e10caec23ae 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -93,6 +93,7 @@ obj-$(CONFIG_GPIO_ML_IOH) += gpio-ml-ioh.o obj-$(CONFIG_GPIO_MLXBF) += gpio-mlxbf.o obj-$(CONFIG_GPIO_MM_LANTIQ) += gpio-mm-lantiq.o obj-$(CONFIG_GPIO_MOCKUP) += gpio-mockup.o +obj-$(CONFIG_GPIO_MOXTET) += gpio-moxtet.o obj-$(CONFIG_GPIO_MPC5200) += gpio-mpc5200.o obj-$(CONFIG_GPIO_MPC8XXX) += gpio-mpc8xxx.o obj-$(CONFIG_GPIO_MSIC) += gpio-msic.o diff --git a/drivers/gpio/gpio-moxtet.c b/drivers/gpio/gpio-moxtet.c new file mode 100644 index 000000000000..3fd729994a38 --- /dev/null +++ b/drivers/gpio/gpio-moxtet.c @@ -0,0 +1,179 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Turris Mox Moxtet GPIO expander + * + * Copyright (C) 2018 Marek Behun <marek.behun@nic.cz> + */ + +#include <linux/bitops.h> +#include <linux/gpio/driver.h> +#include <linux/moxtet.h> +#include <linux/module.h> + +#define MOXTET_GPIO_NGPIOS 12 +#define MOXTET_GPIO_INPUTS 4 + +struct moxtet_gpio_desc { + u16 in_mask; + u16 out_mask; +}; + +static const struct moxtet_gpio_desc descs[] = { + [TURRIS_MOX_MODULE_SFP] = { + .in_mask = GENMASK(2, 0), + .out_mask = GENMASK(5, 4), + }, +}; + +struct moxtet_gpio_chip { + struct device *dev; + struct gpio_chip gpio_chip; + const struct moxtet_gpio_desc *desc; +}; + +static int moxtet_gpio_get_value(struct gpio_chip *gc, unsigned int offset) +{ + struct moxtet_gpio_chip *chip = gpiochip_get_data(gc); + int ret; + + if (chip->desc->in_mask & BIT(offset)) { + ret = moxtet_device_read(chip->dev); + } else if (chip->desc->out_mask & BIT(offset)) { + ret = moxtet_device_written(chip->dev); + if (ret >= 0) + ret <<= MOXTET_GPIO_INPUTS; + } else { + return -EINVAL; + } + + if (ret < 0) + return ret; + + return !!(ret & BIT(offset)); +} + +static void moxtet_gpio_set_value(struct gpio_chip *gc, unsigned int offset, + int val) +{ + struct moxtet_gpio_chip *chip = gpiochip_get_data(gc); + int state; + + state = moxtet_device_written(chip->dev); + if (state < 0) + return; + + offset -= MOXTET_GPIO_INPUTS; + + if (val) + state |= BIT(offset); + else + state &= ~BIT(offset); + + moxtet_device_write(chip->dev, state); +} + +static int moxtet_gpio_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + struct moxtet_gpio_chip *chip = gpiochip_get_data(gc); + + /* All lines are hard wired to be either input or output, not both. */ + if (chip->desc->in_mask & BIT(offset)) + return 1; + else if (chip->desc->out_mask & BIT(offset)) + return 0; + else + return -EINVAL; +} + +static int moxtet_gpio_direction_input(struct gpio_chip *gc, + unsigned int offset) +{ + struct moxtet_gpio_chip *chip = gpiochip_get_data(gc); + + if (chip->desc->in_mask & BIT(offset)) + return 0; + else if (chip->desc->out_mask & BIT(offset)) + return -ENOTSUPP; + else + return -EINVAL; +} + +static int moxtet_gpio_direction_output(struct gpio_chip *gc, + unsigned int offset, int val) +{ + struct moxtet_gpio_chip *chip = gpiochip_get_data(gc); + + if (chip->desc->out_mask & BIT(offset)) + moxtet_gpio_set_value(gc, offset, val); + else if (chip->desc->in_mask & BIT(offset)) + return -ENOTSUPP; + else + return -EINVAL; + + return 0; +} + +static int moxtet_gpio_probe(struct device *dev) +{ + struct moxtet_gpio_chip *chip; + struct device_node *nc = dev->of_node; + int id; + + id = to_moxtet_device(dev)->id; + + if (id >= ARRAY_SIZE(descs)) { + dev_err(dev, "%pOF Moxtet device id 0x%x is not supported by gpio-moxtet driver\n", + nc, id); + return -ENOTSUPP; + } + + chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->dev = dev; + chip->gpio_chip.parent = dev; + chip->desc = &descs[id]; + + dev_set_drvdata(dev, chip); + + chip->gpio_chip.label = dev_name(dev); + chip->gpio_chip.get_direction = moxtet_gpio_get_direction; + chip->gpio_chip.direction_input = moxtet_gpio_direction_input; + chip->gpio_chip.direction_output = moxtet_gpio_direction_output; + chip->gpio_chip.get = moxtet_gpio_get_value; + chip->gpio_chip.set = moxtet_gpio_set_value; + chip->gpio_chip.base = -1; + + chip->gpio_chip.ngpio = MOXTET_GPIO_NGPIOS; + + chip->gpio_chip.can_sleep = true; + chip->gpio_chip.owner = THIS_MODULE; + + return devm_gpiochip_add_data(dev, &chip->gpio_chip, chip); +} + +static const struct of_device_id moxtet_gpio_dt_ids[] = { + { .compatible = "cznic,moxtet-gpio", }, + {}, +}; +MODULE_DEVICE_TABLE(of, moxtet_gpio_dt_ids); + +static const enum turris_mox_module_id moxtet_gpio_module_table[] = { + TURRIS_MOX_MODULE_SFP, + 0, +}; + +static struct moxtet_driver moxtet_gpio_driver = { + .driver = { + .name = "moxtet-gpio", + .of_match_table = moxtet_gpio_dt_ids, + .probe = moxtet_gpio_probe, + }, + .id_table = moxtet_gpio_module_table, +}; +module_moxtet_driver(moxtet_gpio_driver); + +MODULE_AUTHOR("Marek Behun <marek.behun@nic.cz>"); +MODULE_DESCRIPTION("Turris Mox Moxtet GPIO expander"); +MODULE_LICENSE("GPL v2"); |