linux/drivers/auxdisplay/max6959.c
Andy Shevchenko a9bcd02fa4 auxdisplay: Add driver for MAX695x 7-segment LED controllers
Add initial driver for the MAX6958 and MAX6959 7-segment LED
controllers.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-02-26 20:02:35 +02:00

195 lines
4.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* MAX6958/6959 7-segment LED display controller
* Datasheet:
* https://www.analog.com/media/en/technical-documentation/data-sheets/MAX6958-MAX6959.pdf
*
* Copyright (c) 2024, Intel Corporation.
* Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
*/
#include <linux/array_size.h>
#include <linux/bitrev.h>
#include <linux/bits.h>
#include <linux/container_of.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <linux/map_to_7segment.h>
#include "line-display.h"
/* Registers */
#define REG_DECODE_MODE 0x01
#define REG_INTENSITY 0x02
#define REG_SCAN_LIMIT 0x03
#define REG_CONFIGURATION 0x04
#define REG_CONFIGURATION_S_BIT BIT(0)
#define REG_DIGIT(x) (0x20 + (x))
#define REG_DIGIT0 0x20
#define REG_DIGIT1 0x21
#define REG_DIGIT2 0x22
#define REG_DIGIT3 0x23
#define REG_SEGMENTS 0x24
#define REG_MAX REG_SEGMENTS
struct max6959_priv {
struct linedisp linedisp;
struct delayed_work work;
struct regmap *regmap;
};
static void max6959_disp_update(struct work_struct *work)
{
struct max6959_priv *priv = container_of(work, struct max6959_priv, work.work);
struct linedisp *linedisp = &priv->linedisp;
struct linedisp_map *map = linedisp->map;
char *s = linedisp->buf;
u8 buf[4];
/* Map segments according to datasheet */
buf[0] = bitrev8(map_to_seg7(&map->map.seg7, *s++)) >> 1;
buf[1] = bitrev8(map_to_seg7(&map->map.seg7, *s++)) >> 1;
buf[2] = bitrev8(map_to_seg7(&map->map.seg7, *s++)) >> 1;
buf[3] = bitrev8(map_to_seg7(&map->map.seg7, *s++)) >> 1;
regmap_bulk_write(priv->regmap, REG_DIGIT(0), buf, ARRAY_SIZE(buf));
}
static int max6959_linedisp_get_map_type(struct linedisp *linedisp)
{
struct max6959_priv *priv = container_of(linedisp, struct max6959_priv, linedisp);
INIT_DELAYED_WORK(&priv->work, max6959_disp_update);
return LINEDISP_MAP_SEG7;
}
static void max6959_linedisp_update(struct linedisp *linedisp)
{
struct max6959_priv *priv = container_of(linedisp, struct max6959_priv, linedisp);
schedule_delayed_work(&priv->work, 0);
}
static const struct linedisp_ops max6959_linedisp_ops = {
.get_map_type = max6959_linedisp_get_map_type,
.update = max6959_linedisp_update,
};
static int max6959_enable(struct max6959_priv *priv, bool enable)
{
u8 mask = REG_CONFIGURATION_S_BIT;
u8 value = enable ? mask : 0;
return regmap_update_bits(priv->regmap, REG_CONFIGURATION, mask, value);
}
static void max6959_power_off(void *priv)
{
max6959_enable(priv, false);
}
static int max6959_power_on(struct max6959_priv *priv)
{
struct device *dev = regmap_get_device(priv->regmap);
int ret;
ret = max6959_enable(priv, true);
if (ret)
return ret;
return devm_add_action_or_reset(dev, max6959_power_off, priv);
}
static const struct regmap_config max6959_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = REG_MAX,
.cache_type = REGCACHE_MAPLE,
};
static int max6959_i2c_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct max6959_priv *priv;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->regmap = devm_regmap_init_i2c(client, &max6959_regmap_config);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
ret = max6959_power_on(priv);
if (ret)
return ret;
ret = linedisp_register(&priv->linedisp, dev, 4, &max6959_linedisp_ops);
if (ret)
return ret;
i2c_set_clientdata(client, priv);
return 0;
}
static void max6959_i2c_remove(struct i2c_client *client)
{
struct max6959_priv *priv = i2c_get_clientdata(client);
cancel_delayed_work_sync(&priv->work);
linedisp_unregister(&priv->linedisp);
}
static int max6959_suspend(struct device *dev)
{
return max6959_enable(dev_get_drvdata(dev), false);
}
static int max6959_resume(struct device *dev)
{
return max6959_enable(dev_get_drvdata(dev), true);
}
static DEFINE_SIMPLE_DEV_PM_OPS(max6959_pm_ops, max6959_suspend, max6959_resume);
static const struct i2c_device_id max6959_i2c_id[] = {
{ "max6959" },
{ }
};
MODULE_DEVICE_TABLE(i2c, max6959_i2c_id);
static const struct of_device_id max6959_of_table[] = {
{ .compatible = "maxim,max6959" },
{ }
};
MODULE_DEVICE_TABLE(of, max6959_of_table);
static struct i2c_driver max6959_i2c_driver = {
.driver = {
.name = "max6959",
.pm = pm_sleep_ptr(&max6959_pm_ops),
.of_match_table = max6959_of_table,
},
.probe = max6959_i2c_probe,
.remove = max6959_i2c_remove,
.id_table = max6959_i2c_id,
};
module_i2c_driver(max6959_i2c_driver);
MODULE_DESCRIPTION("MAX6958/6959 7-segment LED controller");
MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(LINEDISP);