diff options
Diffstat (limited to 'drivers/gpio/gpio-wm831x.c')
| -rw-r--r-- | drivers/gpio/gpio-wm831x.c | 315 |
1 files changed, 315 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-wm831x.c b/drivers/gpio/gpio-wm831x.c new file mode 100644 index 000000000..a3a32a770 --- /dev/null +++ b/drivers/gpio/gpio-wm831x.c @@ -0,0 +1,315 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * gpiolib support for Wolfson WM831x PMICs + * + * Copyright 2009 Wolfson Microelectronics PLC. + * + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + * + */ + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/gpio/driver.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_putc(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 = &wm831x->pdata; + 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; +#ifdef CONFIG_OF_GPIO + wm831x_gpio->gpio_chip.of_node = wm831x->dev->of_node; +#endif + + 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"); |