Initial Contribution
msm-2.6.38: tag AU_LINUX_ANDROID_GINGERBREAD.02.03.04.00.142
Signed-off-by: Bryan Huntsman <bryanh@codeaurora.org>
diff --git a/drivers/regulator/gpio-regulator.c b/drivers/regulator/gpio-regulator.c
new file mode 100644
index 0000000..b91e32f
--- /dev/null
+++ b/drivers/regulator/gpio-regulator.c
@@ -0,0 +1,221 @@
+/*
+ * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/gpio-regulator.h>
+
+struct gpio_vreg {
+ struct regulator_desc desc;
+ struct regulator_dev *rdev;
+ char *gpio_label;
+ char *name;
+ unsigned gpio;
+ int active_low;
+ bool gpio_requested;
+};
+
+static int gpio_vreg_request_gpio(struct gpio_vreg *vreg)
+{
+ int rc = 0;
+
+ /* Request GPIO now if it hasn't been requested before. */
+ if (!vreg->gpio_requested) {
+ rc = gpio_request(vreg->gpio, vreg->gpio_label);
+ if (rc < 0)
+ pr_err("failed to request gpio %u (%s), rc=%d\n",
+ vreg->gpio, vreg->gpio_label, rc);
+ else
+ vreg->gpio_requested = true;
+
+ rc = gpio_sysfs_set_active_low(vreg->gpio, vreg->active_low);
+ if (rc < 0)
+ pr_err("active_low=%d failed for gpio %u, rc=%d\n",
+ vreg->active_low, vreg->gpio, rc);
+ }
+
+ return rc;
+}
+
+static int gpio_vreg_is_enabled(struct regulator_dev *rdev)
+{
+ struct gpio_vreg *vreg = rdev_get_drvdata(rdev);
+ int rc;
+
+ rc = gpio_vreg_request_gpio(vreg);
+ if (rc < 0)
+ return rc;
+
+ return (gpio_get_value_cansleep(vreg->gpio) ? 1 : 0) ^ vreg->active_low;
+}
+
+static int gpio_vreg_enable(struct regulator_dev *rdev)
+{
+ struct gpio_vreg *vreg = rdev_get_drvdata(rdev);
+ int rc;
+
+ rc = gpio_vreg_request_gpio(vreg);
+ if (rc < 0)
+ return rc;
+
+ return gpio_direction_output(vreg->gpio, !vreg->active_low);
+}
+
+static int gpio_vreg_disable(struct regulator_dev *rdev)
+{
+ struct gpio_vreg *vreg = rdev_get_drvdata(rdev);
+ int rc;
+
+ rc = gpio_vreg_request_gpio(vreg);
+ if (rc < 0)
+ return rc;
+
+ return gpio_direction_output(vreg->gpio, vreg->active_low);
+}
+
+static struct regulator_ops gpio_vreg_ops = {
+ .enable = gpio_vreg_enable,
+ .disable = gpio_vreg_disable,
+ .is_enabled = gpio_vreg_is_enabled,
+};
+
+static int __devinit gpio_vreg_probe(struct platform_device *pdev)
+{
+ const struct gpio_regulator_platform_data *pdata;
+ struct gpio_vreg *vreg;
+ int rc = 0;
+
+ pdata = pdev->dev.platform_data;
+
+ if (!pdata) {
+ pr_err("platform data required.\n");
+ return -EINVAL;
+ }
+
+ if (!pdata->gpio_label) {
+ pr_err("gpio_label required.\n");
+ return -EINVAL;
+ }
+
+ if (!pdata->regulator_name) {
+ pr_err("regulator_name required.\n");
+ return -EINVAL;
+ }
+
+ vreg = kzalloc(sizeof(struct gpio_vreg), GFP_KERNEL);
+ if (!vreg) {
+ pr_err("kzalloc failed.\n");
+ return -ENOMEM;
+ }
+
+ vreg->name = kstrdup(pdata->regulator_name, GFP_KERNEL);
+ if (!vreg->name) {
+ pr_err("kzalloc failed.\n");
+ rc = -ENOMEM;
+ goto free_vreg;
+ }
+
+ vreg->gpio_label = kstrdup(pdata->gpio_label, GFP_KERNEL);
+ if (!vreg->gpio_label) {
+ pr_err("kzalloc failed.\n");
+ rc = -ENOMEM;
+ goto free_name;
+ }
+
+ vreg->gpio = pdata->gpio;
+ vreg->active_low = (pdata->active_low ? 1 : 0);
+ vreg->gpio_requested = false;
+
+ vreg->desc.name = vreg->name;
+ vreg->desc.id = pdev->id;
+ vreg->desc.ops = &gpio_vreg_ops;
+ vreg->desc.type = REGULATOR_VOLTAGE;
+ vreg->desc.owner = THIS_MODULE;
+
+ vreg->rdev = regulator_register(&vreg->desc, &pdev->dev,
+ &pdata->init_data, vreg);
+ if (IS_ERR(vreg->rdev)) {
+ rc = PTR_ERR(vreg->rdev);
+ pr_err("%s: regulator_register failed, rc=%d.\n", vreg->name,
+ rc);
+ goto free_gpio_label;
+ }
+
+ platform_set_drvdata(pdev, vreg);
+
+ pr_info("id=%d, name=%s, gpio=%u, gpio_label=%s\n", pdev->id,
+ vreg->name, vreg->gpio, vreg->gpio_label);
+
+ return rc;
+
+free_gpio_label:
+ kfree(vreg->gpio_label);
+free_name:
+ kfree(vreg->name);
+free_vreg:
+ kfree(vreg);
+
+ return rc;
+}
+
+static int __devexit gpio_vreg_remove(struct platform_device *pdev)
+{
+ struct gpio_vreg *vreg = platform_get_drvdata(pdev);
+
+ if (vreg->gpio_requested)
+ gpio_free(vreg->gpio);
+
+ regulator_unregister(vreg->rdev);
+ kfree(vreg->name);
+ kfree(vreg->gpio_label);
+ kfree(vreg);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+static struct platform_driver gpio_vreg_driver = {
+ .probe = gpio_vreg_probe,
+ .remove = __devexit_p(gpio_vreg_remove),
+ .driver = {
+ .name = GPIO_REGULATOR_DEV_NAME,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init gpio_vreg_init(void)
+{
+ return platform_driver_register(&gpio_vreg_driver);
+}
+
+static void __exit gpio_vreg_exit(void)
+{
+ platform_driver_unregister(&gpio_vreg_driver);
+}
+
+postcore_initcall(gpio_vreg_init);
+module_exit(gpio_vreg_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("GPIO regulator driver");
+MODULE_VERSION("1.0");
+MODULE_ALIAS("platform:" GPIO_REGULATOR_DEV_NAME);