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path: root/drivers/gpio/gpio-wm831x.c
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Diffstat (limited to 'drivers/gpio/gpio-wm831x.c')
-rw-r--r--drivers/gpio/gpio-wm831x.c308
1 files changed, 308 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-wm831x.c b/drivers/gpio/gpio-wm831x.c
new file mode 100644
index 000000000..58ce75c18
--- /dev/null
+++ b/drivers/gpio/gpio-wm831x.c
@@ -0,0 +1,308 @@
+/*
+ * 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 inline struct wm831x_gpio *to_wm831x_gpio(struct gpio_chip *chip)
+{
+ return container_of(chip, struct wm831x_gpio, gpio_chip);
+}
+
+static int wm831x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
+{
+ struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(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 = to_wm831x_gpio(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 = to_wm831x_gpio(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 = to_wm831x_gpio(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 = to_wm831x_gpio(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 gpio_chip *chip, unsigned offset,
+ unsigned debounce)
+{
+ struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(chip);
+ struct wm831x *wm831x = wm831x_gpio->wm831x;
+ 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);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+ struct wm831x_gpio *wm831x_gpio = to_wm831x_gpio(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" : "CMOS",
+ tristated ? " tristated" : "",
+ reg);
+ }
+}
+#else
+#define wm831x_gpio_dbg_show NULL
+#endif
+
+static 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_debounce = wm831x_gpio_set_debounce,
+ .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.dev = &pdev->dev;
+ if (pdata && pdata->gpio_base)
+ wm831x_gpio->gpio_chip.base = pdata->gpio_base;
+ else
+ wm831x_gpio->gpio_chip.base = -1;
+
+ ret = gpiochip_add(&wm831x_gpio->gpio_chip);
+ 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 int wm831x_gpio_remove(struct platform_device *pdev)
+{
+ struct wm831x_gpio *wm831x_gpio = platform_get_drvdata(pdev);
+
+ gpiochip_remove(&wm831x_gpio->gpio_chip);
+ return 0;
+}
+
+static struct platform_driver wm831x_gpio_driver = {
+ .driver.name = "wm831x-gpio",
+ .driver.owner = THIS_MODULE,
+ .probe = wm831x_gpio_probe,
+ .remove = wm831x_gpio_remove,
+};
+
+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");
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-19 19:01:02 +0000