linux-stable/drivers/gpio/gpio-xra1403.c
Thomas Gleixner 9952f6918d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 228 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.107155473@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:52 -07:00

227 lines
5.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* GPIO driver for EXAR XRA1403 16-bit GPIO expander
*
* Copyright (c) 2017, General Electric Company
*/
#include <linux/bitops.h>
#include <linux/gpio/driver.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/seq_file.h>
#include <linux/spi/spi.h>
#include <linux/regmap.h>
/* XRA1403 registers */
#define XRA_GSR 0x00 /* GPIO State */
#define XRA_OCR 0x02 /* Output Control */
#define XRA_PIR 0x04 /* Input Polarity Inversion */
#define XRA_GCR 0x06 /* GPIO Configuration */
#define XRA_PUR 0x08 /* Input Internal Pull-up Resistor Enable/Disable */
#define XRA_IER 0x0A /* Input Interrupt Enable */
#define XRA_TSCR 0x0C /* Output Three-State Control */
#define XRA_ISR 0x0E /* Input Interrupt Status */
#define XRA_REIR 0x10 /* Input Rising Edge Interrupt Enable */
#define XRA_FEIR 0x12 /* Input Falling Edge Interrupt Enable */
#define XRA_IFR 0x14 /* Input Filter Enable/Disable */
#define XRA_LAST 0x15 /* Bounds */
struct xra1403 {
struct gpio_chip chip;
struct regmap *regmap;
};
static const struct regmap_config xra1403_regmap_cfg = {
.reg_bits = 7,
.pad_bits = 1,
.val_bits = 8,
.max_register = XRA_LAST,
};
static unsigned int to_reg(unsigned int reg, unsigned int offset)
{
return reg + (offset > 7);
}
static int xra1403_direction_input(struct gpio_chip *chip, unsigned int offset)
{
struct xra1403 *xra = gpiochip_get_data(chip);
return regmap_update_bits(xra->regmap, to_reg(XRA_GCR, offset),
BIT(offset % 8), BIT(offset % 8));
}
static int xra1403_direction_output(struct gpio_chip *chip, unsigned int offset,
int value)
{
int ret;
struct xra1403 *xra = gpiochip_get_data(chip);
ret = regmap_update_bits(xra->regmap, to_reg(XRA_GCR, offset),
BIT(offset % 8), 0);
if (ret)
return ret;
ret = regmap_update_bits(xra->regmap, to_reg(XRA_OCR, offset),
BIT(offset % 8), value ? BIT(offset % 8) : 0);
return ret;
}
static int xra1403_get_direction(struct gpio_chip *chip, unsigned int offset)
{
int ret;
unsigned int val;
struct xra1403 *xra = gpiochip_get_data(chip);
ret = regmap_read(xra->regmap, to_reg(XRA_GCR, offset), &val);
if (ret)
return ret;
return !!(val & BIT(offset % 8));
}
static int xra1403_get(struct gpio_chip *chip, unsigned int offset)
{
int ret;
unsigned int val;
struct xra1403 *xra = gpiochip_get_data(chip);
ret = regmap_read(xra->regmap, to_reg(XRA_GSR, offset), &val);
if (ret)
return ret;
return !!(val & BIT(offset % 8));
}
static void xra1403_set(struct gpio_chip *chip, unsigned int offset, int value)
{
int ret;
struct xra1403 *xra = gpiochip_get_data(chip);
ret = regmap_update_bits(xra->regmap, to_reg(XRA_OCR, offset),
BIT(offset % 8), value ? BIT(offset % 8) : 0);
if (ret)
dev_err(chip->parent, "Failed to set pin: %d, ret: %d\n",
offset, ret);
}
#ifdef CONFIG_DEBUG_FS
static void xra1403_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
int reg;
struct xra1403 *xra = gpiochip_get_data(chip);
int value[XRA_LAST];
int i;
unsigned int gcr;
unsigned int gsr;
seq_puts(s, "xra reg:");
for (reg = 0; reg <= XRA_LAST; reg++)
seq_printf(s, " %2.2x", reg);
seq_puts(s, "\n value:");
for (reg = 0; reg < XRA_LAST; reg++) {
regmap_read(xra->regmap, reg, &value[reg]);
seq_printf(s, " %2.2x", value[reg]);
}
seq_puts(s, "\n");
gcr = value[XRA_GCR + 1] << 8 | value[XRA_GCR];
gsr = value[XRA_GSR + 1] << 8 | value[XRA_GSR];
for (i = 0; i < chip->ngpio; i++) {
const char *label = gpiochip_is_requested(chip, i);
if (!label)
continue;
seq_printf(s, " gpio-%-3d (%-12s) %s %s\n",
chip->base + i, label,
(gcr & BIT(i)) ? "in" : "out",
(gsr & BIT(i)) ? "hi" : "lo");
}
}
#else
#define xra1403_dbg_show NULL
#endif
static int xra1403_probe(struct spi_device *spi)
{
struct xra1403 *xra;
struct gpio_desc *reset_gpio;
int ret;
xra = devm_kzalloc(&spi->dev, sizeof(*xra), GFP_KERNEL);
if (!xra)
return -ENOMEM;
/* bring the chip out of reset if reset pin is provided*/
reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(reset_gpio))
dev_warn(&spi->dev, "Could not get reset-gpios\n");
xra->chip.direction_input = xra1403_direction_input;
xra->chip.direction_output = xra1403_direction_output;
xra->chip.get_direction = xra1403_get_direction;
xra->chip.get = xra1403_get;
xra->chip.set = xra1403_set;
xra->chip.dbg_show = xra1403_dbg_show;
xra->chip.ngpio = 16;
xra->chip.label = "xra1403";
xra->chip.base = -1;
xra->chip.can_sleep = true;
xra->chip.parent = &spi->dev;
xra->chip.owner = THIS_MODULE;
xra->regmap = devm_regmap_init_spi(spi, &xra1403_regmap_cfg);
if (IS_ERR(xra->regmap)) {
ret = PTR_ERR(xra->regmap);
dev_err(&spi->dev, "Failed to allocate regmap: %d\n", ret);
return ret;
}
ret = devm_gpiochip_add_data(&spi->dev, &xra->chip, xra);
if (ret < 0) {
dev_err(&spi->dev, "Unable to register gpiochip\n");
return ret;
}
spi_set_drvdata(spi, xra);
return 0;
}
static const struct spi_device_id xra1403_ids[] = {
{ "xra1403" },
{},
};
MODULE_DEVICE_TABLE(spi, xra1403_ids);
static const struct of_device_id xra1403_spi_of_match[] = {
{ .compatible = "exar,xra1403" },
{},
};
MODULE_DEVICE_TABLE(of, xra1403_spi_of_match);
static struct spi_driver xra1403_driver = {
.probe = xra1403_probe,
.id_table = xra1403_ids,
.driver = {
.name = "xra1403",
.of_match_table = of_match_ptr(xra1403_spi_of_match),
},
};
module_spi_driver(xra1403_driver);
MODULE_AUTHOR("Nandor Han <nandor.han@ge.com>");
MODULE_AUTHOR("Semi Malinen <semi.malinen@ge.com>");
MODULE_DESCRIPTION("GPIO expander driver for EXAR XRA1403");
MODULE_LICENSE("GPL v2");