leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity
271a8b428f
linux/drivers/gpio/gpio-wm831x.c
Mika Westerberg 2956b5d94a pinctrl / gpio: Introduce .set_config() callback for GPIO chips 
Currently we already have two pin configuration related callbacks
available for GPIO chips .set_single_ended() and .set_debounce(). In
future we expect to have even more, which does not scale well if we need
to add yet another callback to the GPIO chip structure for each possible
configuration parameter.

Better solution is to reuse what we already have available in the
generic pinconf.

To support this, we introduce a new .set_config() callback for GPIO
chips. The callback takes a single packed pin configuration value as
parameter. This can then be extended easily beyond what is currently
supported by just adding new types to the generic pinconf enum.

If the GPIO driver is backed up by a pinctrl driver the GPIO driver can
just assign gpiochip_generic_config() (introduced in this patch) to
.set_config and that will take care configuration requests are directed
to the pinctrl driver.

We then convert the existing drivers over .set_config() and finally
remove the .set_single_ended() and .set_debounce() callbacks.

Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26 15:27:37 +01:00

317 lines
7.6 KiB
C
Raw Blame History

/*
* gpiolib support for Wolfson WM831x PMICs
*
* Copyright 2009 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/mfd/core.h>
#include <linux/platform_device.h>
#include <linux/seq_file.h>
#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/pdata.h>
#include <linux/mfd/wm831x/gpio.h>
#include <linux/mfd/wm831x/irq.h>
struct wm831x_gpio {
struct wm831x *wm831x;
struct gpio_chip gpio_chip;
};
static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
int val = WM831X_GPN_DIR;
if (wm831x->has_gpio_ena)
val |= WM831X_GPN_TRI;
return wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
WM831X_GPN_DIR | WM831X_GPN_TRI |
WM831X_GPN_FN_MASK, val);
}
static int wm831x_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
int ret;
ret = wm831x_reg_read(wm831x, WM831X_GPIO_LEVEL);
if (ret < 0)
return ret;
if (ret & 1 << offset)
return 1;
else
return 0;
}
static void wm831x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
wm831x_set_bits(wm831x, WM831X_GPIO_LEVEL, 1 << offset,
value << offset);
}
static int wm831x_gpio_direction_out(struct gpio_chip *chip,
unsigned offset, int value)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
int val = 0;
int ret;
if (wm831x->has_gpio_ena)
val |= WM831X_GPN_TRI;
ret = wm831x_set_bits(wm831x, WM831X_GPIO1_CONTROL + offset,
WM831X_GPN_DIR | WM831X_GPN_TRI |
WM831X_GPN_FN_MASK, val);
if (ret < 0)
return ret;
/* Can only set GPIO state once it's in output mode */
wm831x_gpio_set(chip, offset, value);
return 0;
}
static int wm831x_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
return irq_create_mapping(wm831x->irq_domain,
WM831X_IRQ_GPIO_1 + offset);
}
static int wm831x_gpio_set_debounce(struct wm831x *wm831x, unsigned offset,
unsigned debounce)
{
int reg = WM831X_GPIO1_CONTROL + offset;
int ret, fn;
ret = wm831x_reg_read(wm831x, reg);
if (ret < 0)
return ret;
switch (ret & WM831X_GPN_FN_MASK) {
case 0:
case 1:
break;
default:
/* Not in GPIO mode */
return -EBUSY;
}
if (debounce >= 32 && debounce <= 64)
fn = 0;
else if (debounce >= 4000 && debounce <= 8000)
fn = 1;
else
return -EINVAL;
return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
}
static int wm831x_set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
int reg = WM831X_GPIO1_CONTROL + offset;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
return wm831x_set_bits(wm831x, reg,
WM831X_GPN_OD_MASK, WM831X_GPN_OD);
case PIN_CONFIG_DRIVE_PUSH_PULL:
return wm831x_set_bits(wm831x, reg,
WM831X_GPN_OD_MASK, 0);
case PIN_CONFIG_INPUT_DEBOUNCE:
return wm831x_gpio_set_debounce(wm831x, offset,
pinconf_to_config_argument(config));
default:
break;
}
return -ENOTSUPP;
}
#ifdef CONFIG_DEBUG_FS
static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
struct wm831x *wm831x = wm831x_gpio->wm831x;
int i, tristated;
for (i = 0; i < chip->ngpio; i++) {
int gpio = i + chip->base;
int reg;
const char *label, *pull, *powerdomain;
/* We report the GPIO even if it's not requested since
* we're also reporting things like alternate
* functions which apply even when the GPIO is not in
* use as a GPIO.
*/
label = gpiochip_is_requested(chip, i);
if (!label)
label = "Unrequested";
seq_printf(s, " gpio-%-3d (%-20.20s) ", gpio, label);
reg = wm831x_reg_read(wm831x, WM831X_GPIO1_CONTROL + i);
if (reg < 0) {
dev_err(wm831x->dev,
"GPIO control %d read failed: %d\n",
gpio, reg);
seq_printf(s, "\n");
continue;
}
switch (reg & WM831X_GPN_PULL_MASK) {
case WM831X_GPIO_PULL_NONE:
pull = "nopull";
break;
case WM831X_GPIO_PULL_DOWN:
pull = "pulldown";
break;
case WM831X_GPIO_PULL_UP:
pull = "pullup";
break;
default:
pull = "INVALID PULL";
break;
}
switch (i + 1) {
case 1 ... 3:
case 7 ... 9:
if (reg & WM831X_GPN_PWR_DOM)
powerdomain = "VPMIC";
else
powerdomain = "DBVDD";
break;
case 4 ... 6:
case 10 ... 12:
if (reg & WM831X_GPN_PWR_DOM)
powerdomain = "SYSVDD";
else
powerdomain = "DBVDD";
break;
case 13 ... 16:
powerdomain = "TPVDD";
break;
default:
BUG();
break;
}
tristated = reg & WM831X_GPN_TRI;
if (wm831x->has_gpio_ena)
tristated = !tristated;
seq_printf(s, " %s %s %s %s%s\n"
" %s%s (0x%4x)\n",
reg & WM831X_GPN_DIR ? "in" : "out",
wm831x_gpio_get(chip, i) ? "high" : "low",
pull,
powerdomain,
reg & WM831X_GPN_POL ? "" : " inverted",
reg & WM831X_GPN_OD ? "open-drain" : "push-pull",
tristated ? " tristated" : "",
reg);
}
}
#else
#define wm831x_gpio_dbg_show NULL
#endif
static const struct gpio_chip template_chip = {
.label = "wm831x",
.owner = THIS_MODULE,
.direction_input = wm831x_gpio_direction_in,
.get = wm831x_gpio_get,
.direction_output = wm831x_gpio_direction_out,
.set = wm831x_gpio_set,
.to_irq = wm831x_gpio_to_irq,
.set_config = wm831x_set_config,
.dbg_show = wm831x_gpio_dbg_show,
.can_sleep = true,
};
static int wm831x_gpio_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
struct wm831x_gpio *wm831x_gpio;
int ret;
wm831x_gpio = devm_kzalloc(&pdev->dev, sizeof(*wm831x_gpio),
GFP_KERNEL);
if (wm831x_gpio == NULL)
return -ENOMEM;
wm831x_gpio->wm831x = wm831x;
wm831x_gpio->gpio_chip = template_chip;
wm831x_gpio->gpio_chip.ngpio = wm831x->num_gpio;
wm831x_gpio->gpio_chip.parent = &pdev->dev;
if (pdata && pdata->gpio_base)
wm831x_gpio->gpio_chip.base = pdata->gpio_base;
else
wm831x_gpio->gpio_chip.base = -1;
ret = devm_gpiochip_add_data(&pdev->dev, &wm831x_gpio->gpio_chip,
wm831x_gpio);
if (ret < 0) {
dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
return ret;
}
platform_set_drvdata(pdev, wm831x_gpio);
return ret;
}
static struct platform_driver wm831x_gpio_driver = {
.driver.name = "wm831x-gpio",
.probe = wm831x_gpio_probe,
};
static int __init wm831x_gpio_init(void)
{
return platform_driver_register(&wm831x_gpio_driver);
}
subsys_initcall(wm831x_gpio_init);
static void __exit wm831x_gpio_exit(void)
{
platform_driver_unregister(&wm831x_gpio_driver);
}
module_exit(wm831x_gpio_exit);
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("GPIO interface for WM831x PMICs");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm831x-gpio");
Reference in New Issue View Git Blame Copy Permalink