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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-01 19:10:44 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-01 19:10:44 (GMT)
commit06d2fe153b9b35e57221e35831a26918f462db68 (patch)
treef77cb72dfba7f2a47ceb93e120abd9399a24a1b9 /drivers/extcon/extcon-gpio.c
parent3aebd34b1200a902a8662da8845824a02f00772e (diff)
parente0f21e6d52cc245e7d4f7e02ca4b7b6571660ec2 (diff)
downloadlinux-fsl-qoriq-06d2fe153b9b35e57221e35831a26918f462db68.tar.xz
Merge tag 'driver-core-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core merge from Greg Kroah-Hartman: "Here is the big driver core update for 3.7-rc1. A number of firmware_class.c updates (as you saw a month or so ago), and some hyper-v updates and some printk fixes as well. All patches that are outside of the drivers/base area have been acked by the respective maintainers, and have all been in the linux-next tree for a while. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" * tag 'driver-core-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (95 commits) memory: tegra{20,30}-mc: Fix reading incorrect register in mc_readl() device.h: Add missing inline to #ifndef CONFIG_PRINTK dev_vprintk_emit memory: emif: Add ifdef CONFIG_DEBUG_FS guard for emif_debugfs_[init|exit] Documentation: Fixes some translation error in Documentation/zh_CN/gpio.txt Documentation: Remove 3 byte redundant code at the head of the Documentation/zh_CN/arm/booting Documentation: Chinese translation of Documentation/video4linux/omap3isp.txt device and dynamic_debug: Use dev_vprintk_emit and dev_printk_emit dev: Add dev_vprintk_emit and dev_printk_emit netdev_printk/netif_printk: Remove a superfluous logging colon netdev_printk/dynamic_netdev_dbg: Directly call printk_emit dev_dbg/dynamic_debug: Update to use printk_emit, optimize stack driver-core: Shut up dev_dbg_reatelimited() without DEBUG tools/hv: Parse /etc/os-release tools/hv: Check for read/write errors tools/hv: Fix exit() error code tools/hv: Fix file handle leak Tools: hv: Implement the KVP verb - KVP_OP_GET_IP_INFO Tools: hv: Rename the function kvp_get_ip_address() Tools: hv: Implement the KVP verb - KVP_OP_SET_IP_INFO Tools: hv: Add an example script to configure an interface ...
Diffstat (limited to 'drivers/extcon/extcon-gpio.c')
-rw-r--r--drivers/extcon/extcon-gpio.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
new file mode 100644
index 0000000..3cc152e
--- /dev/null
+++ b/drivers/extcon/extcon-gpio.c
@@ -0,0 +1,165 @@
+/*
+ * drivers/extcon/extcon_gpio.c
+ *
+ * Single-state GPIO extcon driver based on extcon class
+ *
+ * Copyright (C) 2008 Google, Inc.
+ * Author: Mike Lockwood <lockwood@android.com>
+ *
+ * Modified by MyungJoo Ham <myungjoo.ham@samsung.com> to support extcon
+ * (originally switch class is supported)
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/extcon.h>
+#include <linux/workqueue.h>
+#include <linux/gpio.h>
+#include <linux/extcon.h>
+#include <linux/extcon/extcon_gpio.h>
+
+struct gpio_extcon_data {
+ struct extcon_dev edev;
+ unsigned gpio;
+ const char *state_on;
+ const char *state_off;
+ int irq;
+ struct delayed_work work;
+ unsigned long debounce_jiffies;
+};
+
+static void gpio_extcon_work(struct work_struct *work)
+{
+ int state;
+ struct gpio_extcon_data *data =
+ container_of(to_delayed_work(work), struct gpio_extcon_data,
+ work);
+
+ state = gpio_get_value(data->gpio);
+ extcon_set_state(&data->edev, state);
+}
+
+static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
+{
+ struct gpio_extcon_data *extcon_data = dev_id;
+
+ schedule_delayed_work(&extcon_data->work,
+ extcon_data->debounce_jiffies);
+ return IRQ_HANDLED;
+}
+
+static ssize_t extcon_gpio_print_state(struct extcon_dev *edev, char *buf)
+{
+ struct gpio_extcon_data *extcon_data =
+ container_of(edev, struct gpio_extcon_data, edev);
+ const char *state;
+ if (extcon_get_state(edev))
+ state = extcon_data->state_on;
+ else
+ state = extcon_data->state_off;
+
+ if (state)
+ return sprintf(buf, "%s\n", state);
+ return -EINVAL;
+}
+
+static int __devinit gpio_extcon_probe(struct platform_device *pdev)
+{
+ struct gpio_extcon_platform_data *pdata = pdev->dev.platform_data;
+ struct gpio_extcon_data *extcon_data;
+ int ret = 0;
+
+ if (!pdata)
+ return -EBUSY;
+ if (!pdata->irq_flags) {
+ dev_err(&pdev->dev, "IRQ flag is not specified.\n");
+ return -EINVAL;
+ }
+
+ extcon_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data),
+ GFP_KERNEL);
+ if (!extcon_data)
+ return -ENOMEM;
+
+ extcon_data->edev.name = pdata->name;
+ extcon_data->gpio = pdata->gpio;
+ extcon_data->state_on = pdata->state_on;
+ extcon_data->state_off = pdata->state_off;
+ if (pdata->state_on && pdata->state_off)
+ extcon_data->edev.print_state = extcon_gpio_print_state;
+ extcon_data->debounce_jiffies = msecs_to_jiffies(pdata->debounce);
+
+ ret = extcon_dev_register(&extcon_data->edev, &pdev->dev);
+ if (ret < 0)
+ return ret;
+
+ ret = devm_gpio_request_one(&pdev->dev, extcon_data->gpio, GPIOF_DIR_IN,
+ pdev->name);
+ if (ret < 0)
+ goto err;
+
+ INIT_DELAYED_WORK(&extcon_data->work, gpio_extcon_work);
+
+ extcon_data->irq = gpio_to_irq(extcon_data->gpio);
+ if (extcon_data->irq < 0) {
+ ret = extcon_data->irq;
+ goto err;
+ }
+
+ ret = request_any_context_irq(extcon_data->irq, gpio_irq_handler,
+ pdata->irq_flags, pdev->name,
+ extcon_data);
+ if (ret < 0)
+ goto err;
+
+ platform_set_drvdata(pdev, extcon_data);
+ /* Perform initial detection */
+ gpio_extcon_work(&extcon_data->work.work);
+
+ return 0;
+
+err:
+ extcon_dev_unregister(&extcon_data->edev);
+
+ return ret;
+}
+
+static int __devexit gpio_extcon_remove(struct platform_device *pdev)
+{
+ struct gpio_extcon_data *extcon_data = platform_get_drvdata(pdev);
+
+ cancel_delayed_work_sync(&extcon_data->work);
+ free_irq(extcon_data->irq, extcon_data);
+ extcon_dev_unregister(&extcon_data->edev);
+
+ return 0;
+}
+
+static struct platform_driver gpio_extcon_driver = {
+ .probe = gpio_extcon_probe,
+ .remove = __devexit_p(gpio_extcon_remove),
+ .driver = {
+ .name = "extcon-gpio",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(gpio_extcon_driver);
+
+MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
+MODULE_DESCRIPTION("GPIO extcon driver");
+MODULE_LICENSE("GPL");