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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/mux/gpio.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mux/gpio.c')
-rw-r--r-- | drivers/mux/gpio.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/drivers/mux/gpio.c b/drivers/mux/gpio.c new file mode 100644 index 000000000..cc5f2c186 --- /dev/null +++ b/drivers/mux/gpio.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * GPIO-controlled multiplexer driver + * + * Copyright (C) 2017 Axentia Technologies AB + * + * Author: Peter Rosin <peda@axentia.se> + */ + +#include <linux/bitmap.h> +#include <linux/err.h> +#include <linux/gpio/consumer.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/mux/driver.h> +#include <linux/platform_device.h> +#include <linux/property.h> + +struct mux_gpio { + struct gpio_descs *gpios; +}; + +static int mux_gpio_set(struct mux_control *mux, int state) +{ + struct mux_gpio *mux_gpio = mux_chip_priv(mux->chip); + DECLARE_BITMAP(values, BITS_PER_TYPE(state)); + u32 value = state; + + bitmap_from_arr32(values, &value, BITS_PER_TYPE(value)); + + gpiod_set_array_value_cansleep(mux_gpio->gpios->ndescs, + mux_gpio->gpios->desc, + mux_gpio->gpios->info, values); + + return 0; +} + +static const struct mux_control_ops mux_gpio_ops = { + .set = mux_gpio_set, +}; + +static const struct of_device_id mux_gpio_dt_ids[] = { + { .compatible = "gpio-mux", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, mux_gpio_dt_ids); + +static int mux_gpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mux_chip *mux_chip; + struct mux_gpio *mux_gpio; + int pins; + s32 idle_state; + int ret; + + pins = gpiod_count(dev, "mux"); + if (pins < 0) + return pins; + + mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux_gpio)); + if (IS_ERR(mux_chip)) + return PTR_ERR(mux_chip); + + mux_gpio = mux_chip_priv(mux_chip); + mux_chip->ops = &mux_gpio_ops; + + mux_gpio->gpios = devm_gpiod_get_array(dev, "mux", GPIOD_OUT_LOW); + if (IS_ERR(mux_gpio->gpios)) + return dev_err_probe(dev, PTR_ERR(mux_gpio->gpios), + "failed to get gpios\n"); + WARN_ON(pins != mux_gpio->gpios->ndescs); + mux_chip->mux->states = BIT(pins); + + ret = device_property_read_u32(dev, "idle-state", (u32 *)&idle_state); + if (ret >= 0 && idle_state != MUX_IDLE_AS_IS) { + if (idle_state < 0 || idle_state >= mux_chip->mux->states) { + dev_err(dev, "invalid idle-state %u\n", idle_state); + return -EINVAL; + } + + mux_chip->mux->idle_state = idle_state; + } + + ret = devm_mux_chip_register(dev, mux_chip); + if (ret < 0) + return ret; + + dev_info(dev, "%u-way mux-controller registered\n", + mux_chip->mux->states); + + return 0; +} + +static struct platform_driver mux_gpio_driver = { + .driver = { + .name = "gpio-mux", + .of_match_table = mux_gpio_dt_ids, + }, + .probe = mux_gpio_probe, +}; +module_platform_driver(mux_gpio_driver); + +MODULE_DESCRIPTION("GPIO-controlled multiplexer driver"); +MODULE_AUTHOR("Peter Rosin <peda@axentia.se>"); +MODULE_LICENSE("GPL v2"); |