linux-stable/drivers/gpio/gpio-sama5d2-piobu.c
Lee Jones 392a584698 gpio: gpio-sama5d2-piobu: Demote all kerneldoc headers to basic comment blocks
No attempt has been made to provide proper descriptions for each of
the function arguments throughout the file.  Simply demote all
kerneldoc headers to basic function headers.

Fixes the following W=1 kernel build warnings:

 drivers/gpio/gpio-sama5d2-piobu.c:59: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_setup_pin'
 drivers/gpio/gpio-sama5d2-piobu.c:59: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_setup_pin'
 drivers/gpio/gpio-sama5d2-piobu.c:81: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_write_value'
 drivers/gpio/gpio-sama5d2-piobu.c:81: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_write_value'
 drivers/gpio/gpio-sama5d2-piobu.c:81: warning: Function parameter or member 'mask' not described in 'sama5d2_piobu_write_value'
 drivers/gpio/gpio-sama5d2-piobu.c:81: warning: Function parameter or member 'value' not described in 'sama5d2_piobu_write_value'
 drivers/gpio/gpio-sama5d2-piobu.c:97: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_read_value'
 drivers/gpio/gpio-sama5d2-piobu.c:97: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_read_value'
 drivers/gpio/gpio-sama5d2-piobu.c:97: warning: Function parameter or member 'mask' not described in 'sama5d2_piobu_read_value'
 drivers/gpio/gpio-sama5d2-piobu.c:116: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_get_direction'
 drivers/gpio/gpio-sama5d2-piobu.c:116: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_get_direction'
 drivers/gpio/gpio-sama5d2-piobu.c:131: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_direction_input'
 drivers/gpio/gpio-sama5d2-piobu.c:131: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_direction_input'
 drivers/gpio/gpio-sama5d2-piobu.c:140: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_direction_output'
 drivers/gpio/gpio-sama5d2-piobu.c:140: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_direction_output'
 drivers/gpio/gpio-sama5d2-piobu.c:140: warning: Function parameter or member 'value' not described in 'sama5d2_piobu_direction_output'
 drivers/gpio/gpio-sama5d2-piobu.c:154: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_get'
 drivers/gpio/gpio-sama5d2-piobu.c:154: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_get'
 drivers/gpio/gpio-sama5d2-piobu.c:174: warning: Function parameter or member 'chip' not described in 'sama5d2_piobu_set'
 drivers/gpio/gpio-sama5d2-piobu.c:174: warning: Function parameter or member 'pin' not described in 'sama5d2_piobu_set'
 drivers/gpio/gpio-sama5d2-piobu.c:174: warning: Function parameter or member 'value' not described in 'sama5d2_piobu_set'

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Andrei Stefanescu <andrei.stefanescu@microchip.com>
Link: https://lore.kernel.org/r/20200630133345.2232932-6-lee.jones@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-07-08 09:24:07 +02:00

249 lines
6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* SAMA5D2 PIOBU GPIO controller
*
* Copyright (C) 2018 Microchip Technology Inc. and its subsidiaries
*
* Author: Andrei Stefanescu <andrei.stefanescu@microchip.com>
*
*/
#include <linux/bits.h>
#include <linux/gpio/driver.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define PIOBU_NUM 8
#define PIOBU_REG_SIZE 4
/*
* backup mode protection register for tamper detection
* normal mode protection register for tamper detection
* wakeup signal generation
*/
#define PIOBU_BMPR 0x7C
#define PIOBU_NMPR 0x80
#define PIOBU_WKPR 0x90
#define PIOBU_BASE 0x18 /* PIOBU offset from SECUMOD base register address. */
#define PIOBU_DET_OFFSET 16
/* In the datasheet this bit is called OUTPUT */
#define PIOBU_DIRECTION BIT(8)
#define PIOBU_OUT BIT(8)
#define PIOBU_IN 0
#define PIOBU_SOD BIT(9)
#define PIOBU_PDS BIT(10)
#define PIOBU_HIGH BIT(9)
#define PIOBU_LOW 0
struct sama5d2_piobu {
struct gpio_chip chip;
struct regmap *regmap;
};
/*
* sama5d2_piobu_setup_pin() - prepares a pin for set_direction call
*
* Do not consider pin for tamper detection (normal and backup modes)
* Do not consider pin as tamper wakeup interrupt source
*/
static int sama5d2_piobu_setup_pin(struct gpio_chip *chip, unsigned int pin)
{
int ret;
struct sama5d2_piobu *piobu = container_of(chip, struct sama5d2_piobu,
chip);
unsigned int mask = BIT(PIOBU_DET_OFFSET + pin);
ret = regmap_update_bits(piobu->regmap, PIOBU_BMPR, mask, 0);
if (ret)
return ret;
ret = regmap_update_bits(piobu->regmap, PIOBU_NMPR, mask, 0);
if (ret)
return ret;
return regmap_update_bits(piobu->regmap, PIOBU_WKPR, mask, 0);
}
/*
* sama5d2_piobu_write_value() - writes value & mask at the pin's PIOBU register
*/
static int sama5d2_piobu_write_value(struct gpio_chip *chip, unsigned int pin,
unsigned int mask, unsigned int value)
{
int reg;
struct sama5d2_piobu *piobu = container_of(chip, struct sama5d2_piobu,
chip);
reg = PIOBU_BASE + pin * PIOBU_REG_SIZE;
return regmap_update_bits(piobu->regmap, reg, mask, value);
}
/*
* sama5d2_piobu_read_value() - read the value with masking from the pin's PIOBU
* register
*/
static int sama5d2_piobu_read_value(struct gpio_chip *chip, unsigned int pin,
unsigned int mask)
{
struct sama5d2_piobu *piobu = container_of(chip, struct sama5d2_piobu,
chip);
unsigned int val, reg;
int ret;
reg = PIOBU_BASE + pin * PIOBU_REG_SIZE;
ret = regmap_read(piobu->regmap, reg, &val);
if (ret < 0)
return ret;
return val & mask;
}
/*
* sama5d2_piobu_get_direction() - gpiochip get_direction
*/
static int sama5d2_piobu_get_direction(struct gpio_chip *chip,
unsigned int pin)
{
int ret = sama5d2_piobu_read_value(chip, pin, PIOBU_DIRECTION);
if (ret < 0)
return ret;
return (ret == PIOBU_IN) ? GPIO_LINE_DIRECTION_IN :
GPIO_LINE_DIRECTION_OUT;
}
/*
* sama5d2_piobu_direction_input() - gpiochip direction_input
*/
static int sama5d2_piobu_direction_input(struct gpio_chip *chip,
unsigned int pin)
{
return sama5d2_piobu_write_value(chip, pin, PIOBU_DIRECTION, PIOBU_IN);
}
/*
* sama5d2_piobu_direction_output() - gpiochip direction_output
*/
static int sama5d2_piobu_direction_output(struct gpio_chip *chip,
unsigned int pin, int value)
{
unsigned int val = PIOBU_OUT;
if (value)
val |= PIOBU_HIGH;
return sama5d2_piobu_write_value(chip, pin, PIOBU_DIRECTION | PIOBU_SOD,
val);
}
/*
* sama5d2_piobu_get() - gpiochip get
*/
static int sama5d2_piobu_get(struct gpio_chip *chip, unsigned int pin)
{
/* if pin is input, read value from PDS else read from SOD */
int ret = sama5d2_piobu_get_direction(chip, pin);
if (ret == GPIO_LINE_DIRECTION_IN)
ret = sama5d2_piobu_read_value(chip, pin, PIOBU_PDS);
else if (ret == GPIO_LINE_DIRECTION_OUT)
ret = sama5d2_piobu_read_value(chip, pin, PIOBU_SOD);
if (ret < 0)
return ret;
return !!ret;
}
/*
* sama5d2_piobu_set() - gpiochip set
*/
static void sama5d2_piobu_set(struct gpio_chip *chip, unsigned int pin,
int value)
{
if (!value)
value = PIOBU_LOW;
else
value = PIOBU_HIGH;
sama5d2_piobu_write_value(chip, pin, PIOBU_SOD, value);
}
static int sama5d2_piobu_probe(struct platform_device *pdev)
{
struct sama5d2_piobu *piobu;
int ret, i;
piobu = devm_kzalloc(&pdev->dev, sizeof(*piobu), GFP_KERNEL);
if (!piobu)
return -ENOMEM;
platform_set_drvdata(pdev, piobu);
piobu->chip.label = pdev->name;
piobu->chip.parent = &pdev->dev;
piobu->chip.of_node = pdev->dev.of_node;
piobu->chip.owner = THIS_MODULE,
piobu->chip.get_direction = sama5d2_piobu_get_direction,
piobu->chip.direction_input = sama5d2_piobu_direction_input,
piobu->chip.direction_output = sama5d2_piobu_direction_output,
piobu->chip.get = sama5d2_piobu_get,
piobu->chip.set = sama5d2_piobu_set,
piobu->chip.base = -1,
piobu->chip.ngpio = PIOBU_NUM,
piobu->chip.can_sleep = 0,
piobu->regmap = syscon_node_to_regmap(pdev->dev.of_node);
if (IS_ERR(piobu->regmap)) {
dev_err(&pdev->dev, "Failed to get syscon regmap %ld\n",
PTR_ERR(piobu->regmap));
return PTR_ERR(piobu->regmap);
}
ret = devm_gpiochip_add_data(&pdev->dev, &piobu->chip, piobu);
if (ret) {
dev_err(&pdev->dev, "Failed to add gpiochip %d\n", ret);
return ret;
}
for (i = 0; i < PIOBU_NUM; ++i) {
ret = sama5d2_piobu_setup_pin(&piobu->chip, i);
if (ret) {
dev_err(&pdev->dev, "Failed to setup pin: %d %d\n",
i, ret);
return ret;
}
}
return 0;
}
static const struct of_device_id sama5d2_piobu_ids[] = {
{ .compatible = "atmel,sama5d2-secumod" },
{},
};
MODULE_DEVICE_TABLE(of, sama5d2_piobu_ids);
static struct platform_driver sama5d2_piobu_driver = {
.driver = {
.name = "sama5d2-piobu",
.of_match_table = of_match_ptr(sama5d2_piobu_ids)
},
.probe = sama5d2_piobu_probe,
};
module_platform_driver(sama5d2_piobu_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("SAMA5D2 PIOBU controller driver");
MODULE_AUTHOR("Andrei Stefanescu <andrei.stefanescu@microchip.com>");