diff options
| -rw-r--r-- | drivers/auxdisplay/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/auxdisplay/Makefile | 1 | ||||
| -rw-r--r-- | drivers/auxdisplay/seg-led-gpio.c | 112 |
3 files changed, 124 insertions, 0 deletions
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig index d4be0a3695ce..151d95f96b11 100644 --- a/drivers/auxdisplay/Kconfig +++ b/drivers/auxdisplay/Kconfig @@ -211,6 +211,17 @@ config ARM_CHARLCD line and the Linux version on the second line, but that's still useful. +config SEG_LED_GPIO + tristate "Generic 7-segment LED display" + depends on GPIOLIB || COMPILE_TEST + select LINEDISP + help + This driver supports a generic 7-segment LED display made up + of GPIO pins connected to the individual segments. + + This driver can also be built as a module. If so, the module + will be called seg-led-gpio. + menuconfig PARPORT_PANEL tristate "Parallel port LCD/Keypad Panel support" depends on PARPORT diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile index a725010ca651..4a8ea41b0550 100644 --- a/drivers/auxdisplay/Makefile +++ b/drivers/auxdisplay/Makefile @@ -15,3 +15,4 @@ obj-$(CONFIG_PARPORT_PANEL) += panel.o obj-$(CONFIG_LCD2S) += lcd2s.o obj-$(CONFIG_LINEDISP) += line-display.o obj-$(CONFIG_MAX6959) += max6959.o +obj-$(CONFIG_SEG_LED_GPIO) += seg-led-gpio.o diff --git a/drivers/auxdisplay/seg-led-gpio.c b/drivers/auxdisplay/seg-led-gpio.c new file mode 100644 index 000000000000..5dc2a006cac5 --- /dev/null +++ b/drivers/auxdisplay/seg-led-gpio.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for a 7-segment LED display + * + * The decimal point LED present on some devices is currently not + * supported. + * + * Copyright (C) Allied Telesis Labs + */ + +#include <linux/bitmap.h> +#include <linux/container_of.h> +#include <linux/errno.h> +#include <linux/gpio/consumer.h> +#include <linux/map_to_7segment.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/types.h> +#include <linux/workqueue.h> + +#include "line-display.h" + +struct seg_led_priv { + struct linedisp linedisp; + struct delayed_work work; + struct gpio_descs *segment_gpios; +}; + +static void seg_led_update(struct work_struct *work) +{ + struct seg_led_priv *priv = container_of(work, struct seg_led_priv, work.work); + struct linedisp *linedisp = &priv->linedisp; + struct linedisp_map *map = linedisp->map; + DECLARE_BITMAP(values, 8) = { }; + + bitmap_set_value8(values, map_to_seg7(&map->map.seg7, linedisp->buf[0]), 0); + + gpiod_set_array_value_cansleep(priv->segment_gpios->ndescs, priv->segment_gpios->desc, + priv->segment_gpios->info, values); +} + +static int seg_led_linedisp_get_map_type(struct linedisp *linedisp) +{ + struct seg_led_priv *priv = container_of(linedisp, struct seg_led_priv, linedisp); + + INIT_DELAYED_WORK(&priv->work, seg_led_update); + return LINEDISP_MAP_SEG7; +} + +static void seg_led_linedisp_update(struct linedisp *linedisp) +{ + struct seg_led_priv *priv = container_of(linedisp, struct seg_led_priv, linedisp); + + schedule_delayed_work(&priv->work, 0); +} + +static const struct linedisp_ops seg_led_linedisp_ops = { + .get_map_type = seg_led_linedisp_get_map_type, + .update = seg_led_linedisp_update, +}; + +static int seg_led_probe(struct platform_device *pdev) +{ + struct seg_led_priv *priv; + struct device *dev = &pdev->dev; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + platform_set_drvdata(pdev, priv); + + priv->segment_gpios = devm_gpiod_get_array(dev, "segment", GPIOD_OUT_LOW); + if (IS_ERR(priv->segment_gpios)) + return PTR_ERR(priv->segment_gpios); + + if (priv->segment_gpios->ndescs < 7 || priv->segment_gpios->ndescs > 8) + return -EINVAL; + + return linedisp_register(&priv->linedisp, dev, 1, &seg_led_linedisp_ops); +} + +static int seg_led_remove(struct platform_device *pdev) +{ + struct seg_led_priv *priv = platform_get_drvdata(pdev); + + cancel_delayed_work_sync(&priv->work); + linedisp_unregister(&priv->linedisp); + + return 0; +} + +static const struct of_device_id seg_led_of_match[] = { + { .compatible = "gpio-7-segment"}, + {} +}; +MODULE_DEVICE_TABLE(of, seg_led_of_match); + +static struct platform_driver seg_led_driver = { + .probe = seg_led_probe, + .remove = seg_led_remove, + .driver = { + .name = "seg-led-gpio", + .of_match_table = seg_led_of_match, + }, +}; +module_platform_driver(seg_led_driver); + +MODULE_AUTHOR("Chris Packham <chris.packham@alliedtelesis.co.nz>"); +MODULE_DESCRIPTION("7 segment LED driver"); +MODULE_LICENSE("GPL"); |