1 files changed, 545 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/board-sapphire-h2w.c b/arch/arm/mach-msm/board-sapphire-h2w.c
new file mode 100644
index 000000000000..aa83e216974d
--- /dev/null
+++ b/arch/arm/mach-msm/board-sapphire-h2w.c
@@ -0,0 +1,545 @@
+/*
+ *  H2W device detection driver.
+ *
+ * Copyright (C) 2008 HTC Corporation.
+ * Copyright (C) 2008 Google, Inc.
+ *
+ * Authors:
+ *  Laurence Chen <Laurence_Chen@htc.com>
+ *  Nick Pelly <npelly@google.com>
+ *
+ * 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.
+ *
+ */
+
+/*  For detecting HTC 2 Wire devices, such as wired headset.
+
+    Logically, the H2W driver is always present, and H2W state (hi->state)
+    indicates what is currently plugged into the H2W interface.
+
+    When the headset is plugged in, CABLE_IN1 is pulled low. When the headset
+    button is pressed, CABLE_IN2 is pulled low. These two lines are shared with
+    the TX and RX (respectively) of UART3 - used for serial debugging.
+
+    This headset driver keeps the CPLD configured as UART3 for as long as
+    possible, so that we can do serial FIQ debugging even when the kernel is
+    locked and this driver no longer runs. So it only configures the CPLD to
+    GPIO while the headset is plugged in, and for 10ms during detection work.
+
+    Unfortunately we can't leave the CPLD as UART3 while a headset is plugged
+    in, UART3 is pullup on TX but the headset is pull-down, causing a 55 mA
+    drain on sapphire.
+
+    The headset detection work involves setting CPLD to GPIO, and then pulling
+    CABLE_IN1 high with a stronger pullup than usual. A H2W headset will still
+    pull this line low, whereas other attachments such as a serial console
+    would get pulled up by this stronger pullup.
+
+    Headset insertion/removal causes UEvent's to be sent, and
+    /sys/class/switch/h2w/state to be updated.
+
+    Button presses are interpreted as input event (KEY_MEDIA). Button presses
+    are ignored if the headset is plugged in, so the buttons on 11 pin -> 3.5mm
+    jack adapters do not work until a headset is plugged into the adapter. This
+    is to avoid serial RX traffic causing spurious button press events.
+
+    We tend to check the status of CABLE_IN1 a few more times than strictly
+    necessary during headset detection, to avoid spurious headset insertion
+    events caused by serial debugger TX traffic.
+*/
+
+
+#include <linux/module.h>
+#include <linux/sysdev.h>
+#include <linux/fs.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/hrtimer.h>
+#include <linux/switch.h>
+#include <linux/input.h>
+#include <linux/debugfs.h>
+#include <linux/gpio.h>
+#include <asm/atomic.h>
+#include <mach/board.h>
+#include <mach/vreg.h>
+#include <asm/mach-types.h>
+#include "board-sapphire.h"
+
+#ifdef CONFIG_DEBUG_SAPPHIRE_H2W
+#define H2W_DBG(fmt, arg...) printk(KERN_INFO "[H2W] %s " fmt "\n", __FUNCTION__, ## arg)
+#else
+#define H2W_DBG(fmt, arg...) do {} while (0)
+#endif
+
+static struct workqueue_struct *g_detection_work_queue;
+static void detection_work(struct work_struct *work);
+static DECLARE_WORK(g_detection_work, detection_work);
+enum {
+	NO_DEVICE	= 0,
+	HTC_HEADSET	= 1,
+};
+
+enum {
+	UART3		= 0,
+	GPIO		= 1,
+};
+
+struct h2w_info {
+	struct switch_dev sdev;
+	struct input_dev *input;
+
+	atomic_t btn_state;
+	int ignore_btn;
+
+	unsigned int irq;
+	unsigned int irq_btn;
+
+	struct hrtimer timer;
+	ktime_t debounce_time;
+
+	struct hrtimer btn_timer;
+	ktime_t btn_debounce_time;
+};
+static struct h2w_info *hi;
+
+static ssize_t sapphire_h2w_print_name(struct switch_dev *sdev, char *buf)
+{
+	switch (switch_get_state(&hi->sdev)) {
+	case NO_DEVICE:
+		return sprintf(buf, "No Device\n");
+	case HTC_HEADSET:
+		return sprintf(buf, "Headset\n");
+	}
+	return -EINVAL;
+}
+
+static void configure_cpld(int route)
+{
+	H2W_DBG(" route = %s", route == UART3 ? "UART3" : "GPIO");
+	switch (route) {
+	case UART3:
+		gpio_set_value(SAPPHIRE_GPIO_H2W_SEL0, 0);
+		gpio_set_value(SAPPHIRE_GPIO_H2W_SEL1, 1);
+		break;
+	case GPIO:
+		gpio_set_value(SAPPHIRE_GPIO_H2W_SEL0, 0);
+		gpio_set_value(SAPPHIRE_GPIO_H2W_SEL1, 0);
+		break;
+	}
+}
+
+static void button_pressed(void)
+{
+	H2W_DBG("");
+	atomic_set(&hi->btn_state, 1);
+	input_report_key(hi->input, KEY_MEDIA, 1);
+	input_sync(hi->input);
+}
+
+static void button_released(void)
+{
+	H2W_DBG("");
+	atomic_set(&hi->btn_state, 0);
+	input_report_key(hi->input, KEY_MEDIA, 0);
+	input_sync(hi->input);
+}
+
+#ifdef CONFIG_MSM_SERIAL_DEBUGGER
+extern void msm_serial_debug_enable(int);
+#endif
+
+static void insert_headset(void)
+{
+	unsigned long irq_flags;
+
+	H2W_DBG("");
+
+	switch_set_state(&hi->sdev, HTC_HEADSET);
+	configure_cpld(GPIO);
+
+#ifdef CONFIG_MSM_SERIAL_DEBUGGER
+	msm_serial_debug_enable(false);
+#endif
+
+
+	/* On some non-standard headset adapters (usually those without a
+	 * button) the btn line is pulled down at the same time as the detect
+	 * line. We can check here by sampling the button line, if it is
+	 * low then it is probably a bad adapter so ignore the button.
+	 * If the button is released then we stop ignoring the button, so that
+	 * the user can recover from the situation where a headset is plugged
+	 * in with button held down.
+	 */
+	hi->ignore_btn = !gpio_get_value(SAPPHIRE_GPIO_CABLE_IN2);
+
+	/* Enable button irq */
+	local_irq_save(irq_flags);
+	enable_irq(hi->irq_btn);
+	local_irq_restore(irq_flags);
+
+	hi->debounce_time = ktime_set(0, 20000000);  /* 20 ms */
+}
+
+static void remove_headset(void)
+{
+	unsigned long irq_flags;
+
+	H2W_DBG("");
+
+	switch_set_state(&hi->sdev, NO_DEVICE);
+	configure_cpld(UART3);
+
+	/* Disable button */
+	local_irq_save(irq_flags);
+	disable_irq(hi->irq_btn);
+	local_irq_restore(irq_flags);
+
+	if (atomic_read(&hi->btn_state))
+		button_released();
+
+	hi->debounce_time = ktime_set(0, 100000000);  /* 100 ms */
+}
+
+static void detection_work(struct work_struct *work)
+{
+	unsigned long irq_flags;
+	int clk, cable_in1;
+
+	H2W_DBG("");
+
+	if (gpio_get_value(SAPPHIRE_GPIO_CABLE_IN1) != 0) {
+		/* Headset not plugged in */
+		if (switch_get_state(&hi->sdev) == HTC_HEADSET)
+			remove_headset();
+		return;
+	}
+
+	/* Something plugged in, lets make sure its a headset */
+
+	/* Switch CPLD to GPIO to do detection */
+	configure_cpld(GPIO);
+	/* Disable headset interrupt while detecting.*/
+	local_irq_save(irq_flags);
+	disable_irq(hi->irq);
+	local_irq_restore(irq_flags);
+
+	/* Set GPIO_CABLE_IN1 as output high */
+	gpio_direction_output(SAPPHIRE_GPIO_CABLE_IN1, 1);
+	/* Delay 10ms for pin stable. */
+	msleep(10);
+	/* Save H2W_CLK */
+	clk = gpio_get_value(SAPPHIRE_GPIO_H2W_CLK_GPI);
+	/* Set GPIO_CABLE_IN1 as input */
+	gpio_direction_input(SAPPHIRE_GPIO_CABLE_IN1);
+
+	/* Restore IRQs */
+	local_irq_save(irq_flags);
+	enable_irq(hi->irq);
+	local_irq_restore(irq_flags);
+
+	cable_in1 = gpio_get_value(SAPPHIRE_GPIO_CABLE_IN1);
+
+	if (cable_in1 == 0 && clk == 0) {
+		if (switch_get_state(&hi->sdev) == NO_DEVICE)
+			insert_headset();
+	} else {
+		configure_cpld(UART3);
+		H2W_DBG("CABLE_IN1 was low, but not a headset "
+			"(recent cable_in1 = %d, clk = %d)", cable_in1, clk);
+	}
+}
+
+static enum hrtimer_restart button_event_timer_func(struct hrtimer *data)
+{
+	H2W_DBG("");
+
+	if (switch_get_state(&hi->sdev) == HTC_HEADSET) {
+		if (gpio_get_value(SAPPHIRE_GPIO_CABLE_IN2)) {
+			if (hi->ignore_btn)
+				hi->ignore_btn = 0;
+			else if (atomic_read(&hi->btn_state))
+				button_released();
+		} else {
+			if (!hi->ignore_btn && !atomic_read(&hi->btn_state))
+				button_pressed();
+		}
+	}
+
+	return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart detect_event_timer_func(struct hrtimer *data)
+{
+	H2W_DBG("");
+
+	queue_work(g_detection_work_queue, &g_detection_work);
+	return HRTIMER_NORESTART;
+}
+
+static irqreturn_t detect_irq_handler(int irq, void *dev_id)
+{
+	int value1, value2;
+	int retry_limit = 10;
+
+	H2W_DBG("");
+	do {
+		value1 = gpio_get_value(SAPPHIRE_GPIO_CABLE_IN1);
+		set_irq_type(hi->irq, value1 ?
+				IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH);
+		value2 = gpio_get_value(SAPPHIRE_GPIO_CABLE_IN1);
+	} while (value1 != value2 && retry_limit-- > 0);
+
+	H2W_DBG("value2 = %d (%d retries)", value2, (10-retry_limit));
+
+	if ((switch_get_state(&hi->sdev) == NO_DEVICE) ^ value2) {
+		if (switch_get_state(&hi->sdev) == HTC_HEADSET)
+			hi->ignore_btn = 1;
+		/* Do the rest of the work in timer context */
+		hrtimer_start(&hi->timer, hi->debounce_time, HRTIMER_MODE_REL);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t button_irq_handler(int irq, void *dev_id)
+{
+	int value1, value2;
+	int retry_limit = 10;
+
+	H2W_DBG("");
+	do {
+		value1 = gpio_get_value(SAPPHIRE_GPIO_CABLE_IN2);
+		set_irq_type(hi->irq_btn, value1 ?
+				IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH);
+		value2 = gpio_get_value(SAPPHIRE_GPIO_CABLE_IN2);
+	} while (value1 != value2 && retry_limit-- > 0);
+
+	H2W_DBG("value2 = %d (%d retries)", value2, (10-retry_limit));
+
+	hrtimer_start(&hi->btn_timer, hi->btn_debounce_time, HRTIMER_MODE_REL);
+
+	return IRQ_HANDLED;
+}
+
+#if defined(CONFIG_DEBUG_FS)
+static void h2w_debug_set(void *data, u64 val)
+{
+	switch_set_state(&hi->sdev, (int)val);
+}
+
+static u64 h2w_debug_get(void *data)
+{
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(h2w_debug_fops, h2w_debug_get, h2w_debug_set, "%llu\n");
+static int __init h2w_debug_init(void)
+{
+	struct dentry *dent;
+
+	dent = debugfs_create_dir("h2w", 0);
+	if (IS_ERR(dent))
+		return PTR_ERR(dent);
+
+	debugfs_create_file("state", 0644, dent, NULL, &h2w_debug_fops);
+
+	return 0;
+}
+
+device_initcall(h2w_debug_init);
+#endif
+
+static int sapphire_h2w_probe(struct platform_device *pdev)
+{
+	int ret;
+	unsigned long irq_flags;
+
+	printk(KERN_INFO "H2W: Registering H2W (headset) driver\n");
+	hi = kzalloc(sizeof(struct h2w_info), GFP_KERNEL);
+	if (!hi)
+		return -ENOMEM;
+
+	atomic_set(&hi->btn_state, 0);
+	hi->ignore_btn = 0;
+
+	hi->debounce_time = ktime_set(0, 100000000);  /* 100 ms */
+	hi->btn_debounce_time = ktime_set(0, 10000000); /* 10 ms */
+	hi->sdev.name = "h2w";
+	hi->sdev.print_name = sapphire_h2w_print_name;
+
+	ret = switch_dev_register(&hi->sdev);
+	if (ret < 0)
+		goto err_switch_dev_register;
+
+	g_detection_work_queue = create_workqueue("detection");
+	if (g_detection_work_queue == NULL) {
+		ret = -ENOMEM;
+		goto err_create_work_queue;
+	}
+
+	ret = gpio_request(SAPPHIRE_GPIO_CABLE_IN1, "h2w_detect");
+	if (ret < 0)
+		goto err_request_detect_gpio;
+
+	ret = gpio_request(SAPPHIRE_GPIO_CABLE_IN2, "h2w_button");
+	if (ret < 0)
+		goto err_request_button_gpio;
+
+	ret = gpio_direction_input(SAPPHIRE_GPIO_CABLE_IN1);
+	if (ret < 0)
+		goto err_set_detect_gpio;
+
+	ret = gpio_direction_input(SAPPHIRE_GPIO_CABLE_IN2);
+	if (ret < 0)
+		goto err_set_button_gpio;
+
+	hi->irq = gpio_to_irq(SAPPHIRE_GPIO_CABLE_IN1);
+	if (hi->irq < 0) {
+		ret = hi->irq;
+		goto err_get_h2w_detect_irq_num_failed;
+	}
+
+	hi->irq_btn = gpio_to_irq(SAPPHIRE_GPIO_CABLE_IN2);
+	if (hi->irq_btn < 0) {
+		ret = hi->irq_btn;
+		goto err_get_button_irq_num_failed;
+	}
+
+	/* Set CPLD MUX to H2W <-> CPLD GPIO */
+	configure_cpld(UART3);
+	/* Set the CPLD connected H2W GPIO's to input */
+	gpio_set_value(SAPPHIRE_GPIO_H2W_CLK_DIR, 0);
+	gpio_set_value(SAPPHIRE_GPIO_H2W_DAT_DIR, 0);
+
+	hrtimer_init(&hi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hi->timer.function = detect_event_timer_func;
+	hrtimer_init(&hi->btn_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hi->btn_timer.function = button_event_timer_func;
+
+	ret = request_irq(hi->irq, detect_irq_handler,
+			  IRQF_TRIGGER_LOW, "h2w_detect", NULL);
+	if (ret < 0)
+		goto err_request_detect_irq;
+
+	/* Disable button until plugged in */
+	set_irq_flags(hi->irq_btn, IRQF_VALID | IRQF_NOAUTOEN);
+	ret = request_irq(hi->irq_btn, button_irq_handler,
+			  IRQF_TRIGGER_LOW, "h2w_button", NULL);
+	if (ret < 0)
+		goto err_request_h2w_headset_button_irq;
+
+	ret = set_irq_wake(hi->irq, 1);
+	if (ret < 0)
+		goto err_request_input_dev;
+	ret = set_irq_wake(hi->irq_btn, 1);
+	if (ret < 0)
+		goto err_request_input_dev;
+
+	hi->input = input_allocate_device();
+	if (!hi->input) {
+		ret = -ENOMEM;
+		goto err_request_input_dev;
+	}
+
+	hi->input->name = "h2w headset";
+	hi->input->evbit[0] = BIT_MASK(EV_KEY);
+	hi->input->keybit[BIT_WORD(KEY_MEDIA)] = BIT_MASK(KEY_MEDIA);
+
+	ret = input_register_device(hi->input);
+	if (ret < 0)
+		goto err_register_input_dev;
+
+	return 0;
+
+err_register_input_dev:
+	input_free_device(hi->input);
+err_request_input_dev:
+	free_irq(hi->irq_btn, 0);
+err_request_h2w_headset_button_irq:
+	free_irq(hi->irq, 0);
+err_request_detect_irq:
+err_get_button_irq_num_failed:
+err_get_h2w_detect_irq_num_failed:
+err_set_button_gpio:
+err_set_detect_gpio:
+	gpio_free(SAPPHIRE_GPIO_CABLE_IN2);
+err_request_button_gpio:
+	gpio_free(SAPPHIRE_GPIO_CABLE_IN1);
+err_request_detect_gpio:
+	destroy_workqueue(g_detection_work_queue);
+err_create_work_queue:
+	switch_dev_unregister(&hi->sdev);
+err_switch_dev_register:
+	printk(KERN_ERR "H2W: Failed to register driver\n");
+
+	return ret;
+}
+
+static int sapphire_h2w_remove(struct platform_device *pdev)
+{
+	H2W_DBG("");
+	if (switch_get_state(&hi->sdev))
+		remove_headset();
+	input_unregister_device(hi->input);
+	gpio_free(SAPPHIRE_GPIO_CABLE_IN2);
+	gpio_free(SAPPHIRE_GPIO_CABLE_IN1);
+	free_irq(hi->irq_btn, 0);
+	free_irq(hi->irq, 0);
+	destroy_workqueue(g_detection_work_queue);
+	switch_dev_unregister(&hi->sdev);
+
+	return 0;
+}
+
+static struct platform_device sapphire_h2w_device = {
+	.name		= "sapphire-h2w",
+};
+
+static struct platform_driver sapphire_h2w_driver = {
+	.probe		= sapphire_h2w_probe,
+	.remove		= sapphire_h2w_remove,
+	.driver		= {
+		.name		= "sapphire-h2w",
+		.owner		= THIS_MODULE,
+	},
+};
+
+static int __init sapphire_h2w_init(void)
+{
+	if (!machine_is_sapphire())
+		return 0;
+	int ret;
+	H2W_DBG("");
+	ret = platform_driver_register(&sapphire_h2w_driver);
+	if (ret)
+		return ret;
+	return platform_device_register(&sapphire_h2w_device);
+}
+
+static void __exit sapphire_h2w_exit(void)
+{
+	platform_device_unregister(&sapphire_h2w_device);
+	platform_driver_unregister(&sapphire_h2w_driver);
+}
+
+module_init(sapphire_h2w_init);
+module_exit(sapphire_h2w_exit);
+
+MODULE_AUTHOR("Laurence Chen <Laurence_Chen@htc.com>");
+MODULE_DESCRIPTION("HTC 2 Wire detection driver for sapphire");
+MODULE_LICENSE("GPL");