1 files changed, 306 insertions, 0 deletions
diff --git a/drivers/misc/sim_detect.c b/drivers/misc/sim_detect.c
new file mode 100644
index 00000000000..e67f4fad3db
--- /dev/null
+++ b/drivers/misc/sim_detect.c
@@ -0,0 +1,306 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: BIBEK BASU <bibek.basu@stericsson.com>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/hrtimer.h>
+#include <linux/workqueue.h>
+#include <linux/uaccess.h>
+#include <linux/modem/modem_client.h>
+#include <mach/sim_detect.h>
+#include <linux/regulator/consumer.h>
+
+/* time in millisec */
+#define TIMER_DELAY	10
+
+struct sim_detect{
+	struct work_struct	timer_expired;
+	struct device	*dev;
+	struct modem *modem;
+	struct hrtimer timer;
+	struct mutex lock;
+	int voltage;
+	struct regulator *vinvsim_regulator;
+	bool regulator_enabled;
+};
+
+static ssize_t show_voltage(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	struct sim_detect *data = dev_get_drvdata(dev);
+	int ret, len;
+
+	ret = mutex_lock_interruptible(&data->lock);
+	if (ret < 0)
+		return ret;
+
+	len = sprintf(buf, "%i\n", data->voltage);
+
+	mutex_unlock(&data->lock);
+
+	return len;
+}
+
+static ssize_t write_voltage(struct device *dev, struct device_attribute *attr,
+			     const char *buf, size_t count)
+{
+	struct sim_detect *sim_detect = dev_get_drvdata(dev);
+	long val;
+	int ret;
+
+	/* check input */
+	if (strict_strtol(buf, 0, &val) != 0) {
+		dev_err(dev, "Invalid voltage class configured.\n");
+		return -EINVAL;
+	}
+
+	switch (val) {
+	case -1:
+	case 0:
+	case 1800000:
+	case 3000000:
+		break;
+	default:
+		dev_err(dev, "Invalid voltage class configured.\n");
+		return -EINVAL;
+	}
+
+	/* lock */
+	ret = mutex_lock_interruptible(&sim_detect->lock);
+	if (ret < 0)
+		return ret;
+
+	/* update state */
+	sim_detect->voltage = val;
+
+	/* call regulator */
+	switch (sim_detect->voltage) {
+	case 0:
+		/* SIM voltage is unknown, turn on regulator for 3 V SIM */
+	case 3000000:
+		/* Vinvsim supply is used only for 3 V SIM */
+		if (!sim_detect->regulator_enabled) {
+			ret = regulator_enable(sim_detect->vinvsim_regulator);
+			if (ret) {
+				dev_err(dev, "Failed to enable regulator.\n");
+				goto out_unlock;
+			}
+			sim_detect->regulator_enabled = true;
+		}
+		break;
+	case 1800000:
+	case -1:
+		/* Vbatvsim is used otherwise */
+		if (sim_detect->regulator_enabled) {
+			regulator_disable(sim_detect->vinvsim_regulator);
+			sim_detect->regulator_enabled = false;
+		}
+	}
+
+out_unlock:
+	/* unlock and return */
+	mutex_unlock(&sim_detect->lock);
+
+	return count;
+}
+
+static DEVICE_ATTR(voltage, S_IWUGO | S_IRUGO, show_voltage, write_voltage);
+
+static struct attribute *sim_attributes[] = {
+	&dev_attr_voltage.attr,
+	NULL
+};
+
+static const struct attribute_group sim_attr_group = {
+	.attrs	= sim_attributes,
+};
+
+static void inform_modem_release(struct work_struct *work)
+{
+	struct sim_detect *sim_detect =
+		container_of(work, struct sim_detect, timer_expired);
+
+	/* call Modem Access Framework api to release modem */
+	modem_release(sim_detect->modem);
+}
+
+static enum hrtimer_restart timer_callback(struct hrtimer *timer)
+{
+	struct sim_detect *sim_detect =
+		container_of(timer, struct sim_detect, timer);
+
+	schedule_work(&sim_detect->timer_expired);
+	return HRTIMER_NORESTART;
+}
+
+static irqreturn_t sim_activity_irq(int irq, void *dev)
+{
+	struct sim_detect *sim_detect = dev;
+
+	/* call Modem Access Framework api to acquire modem */
+	modem_request(sim_detect->modem);
+	/* start the timer for 10ms */
+	hrtimer_start(&sim_detect->timer,
+			ktime_set(0, TIMER_DELAY*NSEC_PER_MSEC),
+			HRTIMER_MODE_REL);
+	return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_PM
+/**
+ * sim_detect_suspend() - This routine puts the Sim detect in to sustend state.
+ * @dev:	pointer to device structure.
+ *
+ * This routine checks the current ongoing communication with Modem by
+ * examining the modem_get_usage and work_pending state.
+ * accordingly prevents suspend if modem communication
+ * is on-going.
+ */
+int sim_detect_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct sim_detect *sim_detect = platform_get_drvdata(pdev);
+
+	dev_dbg(&pdev->dev, "%s called...\n", __func__);
+	/* if modem is accessed, event system suspend */
+	if (modem_get_usage(sim_detect->modem)
+			|| work_pending(&sim_detect->timer_expired))
+		return -EBUSY;
+	else
+		return 0;
+}
+
+static const struct dev_pm_ops sim_detect_dev_pm_ops = {
+	.suspend = sim_detect_suspend,
+};
+#endif
+
+
+static int __devinit sim_detect_probe(struct platform_device *pdev)
+{
+	struct sim_detect_platform_data *plat = dev_get_platdata(&pdev->dev);
+	struct sim_detect *sim_detect;
+	int ret;
+
+	sim_detect = kzalloc(sizeof(struct sim_detect), GFP_KERNEL);
+	if (sim_detect == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	/* initialize data */
+	mutex_init(&sim_detect->lock);
+	sim_detect->voltage = 0;
+
+	sim_detect->dev = &pdev->dev;
+	INIT_WORK(&sim_detect->timer_expired, inform_modem_release);
+	hrtimer_init(&sim_detect->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	sim_detect->timer.function = timer_callback;
+
+	sim_detect->modem = modem_get(sim_detect->dev, "u8500-shrm-modem");
+	if (IS_ERR(sim_detect->modem)) {
+		ret = PTR_ERR(sim_detect->modem);
+		dev_err(sim_detect->dev, "Could not retrieve the modem\n");
+		goto out_free;
+	}
+
+	/* set drvdata */
+	platform_set_drvdata(pdev, sim_detect);
+
+	/* request irq */
+	ret = request_threaded_irq(plat->irq_num,
+		       NULL, sim_activity_irq,
+		       IRQF_TRIGGER_FALLING |
+		       IRQF_TRIGGER_RISING |
+		       IRQF_NO_SUSPEND,
+		       "sim activity", sim_detect);
+	if (ret < 0)
+		goto out_put_modem;
+
+	/* get regulator */
+	sim_detect->regulator_enabled = false;
+	sim_detect->vinvsim_regulator = regulator_get(sim_detect->dev,
+							 "vinvsim");
+	if (IS_ERR(sim_detect->vinvsim_regulator)) {
+		dev_err(&pdev->dev,
+			"Failed to get regulator. (dev_name %s).\n",
+			dev_name(sim_detect->dev));
+		ret = PTR_ERR(sim_detect->vinvsim_regulator);
+		goto out_free_irq;
+	}
+
+	/* register sysfs entry */
+	ret = sysfs_create_group(&pdev->dev.kobj, &sim_attr_group);
+	if (ret != 0) {
+		dev_err(&pdev->dev,
+			"Failed to create attribute group: %d\n", ret);
+		goto out_free_regulator;
+	}
+
+	return 0;
+
+out_free_regulator:
+	regulator_put(sim_detect->vinvsim_regulator);
+out_free_irq:
+	free_irq(plat->irq_num, sim_detect);
+out_put_modem:
+	modem_put(sim_detect->modem);
+	platform_set_drvdata(pdev, NULL);
+out_free:
+	kfree(sim_detect);
+	return ret;
+}
+
+static int __devexit sim_detect_remove(struct platform_device *pdev)
+{
+	struct sim_detect *sim_detect = platform_get_drvdata(pdev);
+
+	sysfs_remove_group(&pdev->dev.kobj, &sim_attr_group);
+	regulator_put(sim_detect->vinvsim_regulator);
+	modem_put(sim_detect->modem);
+	platform_set_drvdata(pdev, NULL);
+	kfree(sim_detect);
+	return 0;
+}
+
+static struct platform_driver sim_detect_driver = {
+	.driver = {
+		.name = "sim-detect",
+		.owner = THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm = &sim_detect_dev_pm_ops,
+#endif
+	},
+	.probe = sim_detect_probe,
+	.remove = __devexit_p(sim_detect_remove),
+};
+
+static int __init sim_detect_init(void)
+{
+	return platform_driver_register(&sim_detect_driver);
+}
+module_init(sim_detect_init);
+
+static void __exit sim_detect_exit(void)
+{
+	platform_driver_unregister(&sim_detect_driver);
+}
+module_exit(sim_detect_exit);
+
+MODULE_AUTHOR("BIBEK BASU <bibek.basu@stericsson.com>");
+MODULE_DESCRIPTION("Detects SIM Hot Swap and wakes modem");
+MODULE_ALIAS("platform:sim-detect");
+MODULE_LICENSE("GPL v2");