Merge "misc: Add APQ8084 Docking Station driver"

Documentation/devicetree/bindings/misc/apq8084_dock.txt

@@ -0,0 +1,17 @@
+QTI APQ8084 Docking Station
+
+This device describes the interface used when connecting to the
+Docking Station's USB hub and Ethernet ports. The interface
+consists of GPIOs used for controlling the main power supply
+and reset lines.
+
+Required properties:
+ - compatible: Should be "qti,apq8084-dock"
+ - qti,dock-detect-gpio: phandle to a GPIO node corresponding to the input
+                         signal indicating when the dock is connected
+ - qti,dock-enable-gpio: phandle to a GPIO node corresponding to the output
+                         signal that turns on/off power to the ports
+ - qti,dock-hub-reset-gpio: phandle to a GPIO node corresponding to the output
+                            signal that resets the USB ports
+ - qti,dock-eth-reset-gpio: phandle to a GPIO node corresponding to the output
+                            signal that resets the Ethernet ports

drivers/misc/Kconfig

@@ -602,6 +602,13 @@ config TI_DRV2667
 	  To compile this driver as a module, choose M here: the
 	  module will be called ti_drv2667.
 
+config APQ8084_DOCKING_STATION
+	tristate "QTI APQ8084 Docking Station USB/Ethernet support"
+	depends on OF_GPIO
+	help
+	  This option enables support for the USB and Ethernet ports found on
+	  the QTI APQ8084 Docking Station.
+
 source "drivers/misc/c2port/Kconfig"
 source "drivers/misc/eeprom/Kconfig"
 source "drivers/misc/cb710/Kconfig"

drivers/misc/Makefile

@@ -61,3 +61,4 @@ obj-$(CONFIG_QSEECOM) += qseecom.o
 obj-$(CONFIG_QFP_FUSE) += qfp_fuse.o
 obj-$(CONFIG_TI_DRV2667) += ti_drv2667.o
 obj-$(CONFIG_QPNP_MISC) += qpnp-misc.o
+obj-$(CONFIG_APQ8084_DOCKING_STATION)	+= apq8084_dock.o

drivers/misc/apq8084_dock.c

@@ -0,0 +1,168 @@
+/* Copyright (c) 2013, The Linux Foundation. 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.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeup.h>
+#include <linux/workqueue.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+
+struct apq8084_dock {
+	struct device		*dev;
+	struct work_struct	dock_work;
+	int			dock_detect;
+	int			dock_hub_reset;
+	int			dock_eth_reset;
+	int			dock_enable;
+};
+
+static void dock_detected_work(struct work_struct *w)
+{
+	struct apq8084_dock *dock = container_of(w, struct apq8084_dock,
+						 dock_work);
+	int docked;
+
+	docked = gpio_get_value(dock->dock_detect);
+	gpio_direction_output(dock->dock_enable, 0);
+
+	if (docked) {
+		/* assert RESETs before turning on power */
+		gpio_direction_output(dock->dock_hub_reset, 1);
+		gpio_direction_output(dock->dock_eth_reset, 1);
+		gpio_direction_output(dock->dock_enable, 1);
+
+		msleep(20); /* short delay before de-asserting RESETs */
+		gpio_direction_output(dock->dock_hub_reset, 0);
+		gpio_direction_output(dock->dock_eth_reset, 0);
+	}
+
+	/* Allow system suspend */
+	pm_relax(dock->dev);
+}
+
+static irqreturn_t dock_detected(int irq, void *data)
+{
+	struct apq8084_dock *dock = data;
+
+	/* Ensure suspend can't happen until after work function commpletes */
+	pm_stay_awake(dock->dev);
+	schedule_work(&dock->dock_work);
+	return IRQ_HANDLED;
+}
+
+static int apq8084_dock_probe(struct platform_device *pdev)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct apq8084_dock *dock;
+	int ret;
+
+	dock = devm_kzalloc(&pdev->dev, sizeof(*dock), GFP_KERNEL);
+	if (!dock)
+		return -ENOMEM;
+
+	dock->dev = &pdev->dev;
+	platform_set_drvdata(pdev, dock);
+	INIT_WORK(&dock->dock_work, dock_detected_work);
+
+	dock->dock_detect = of_get_named_gpio(node, "qti,dock-detect-gpio", 0);
+	if (dock->dock_detect < 0) {
+		dev_err(dock->dev, "unable to get dock-detect-gpio\n");
+		return dock->dock_detect;
+	}
+
+	ret = devm_gpio_request(dock->dev, dock->dock_detect, "dock_detect");
+	if (ret)
+		return ret;
+
+	ret = devm_request_irq(&pdev->dev, gpio_to_irq(dock->dock_detect),
+				dock_detected, IRQF_TRIGGER_RISING |
+				IRQF_TRIGGER_FALLING | IRQF_SHARED,
+				"dock_detect_irq", dock);
+	if (ret)
+		return ret;
+
+	dock->dock_hub_reset = of_get_named_gpio(node,
+						 "qti,dock-hub-reset-gpio", 0);
+	if (dock->dock_hub_reset < 0) {
+		dev_err(dock->dev, "unable to get dock-hub-reset-gpio\n");
+		return dock->dock_hub_reset;
+	}
+
+	ret = devm_gpio_request(dock->dev, dock->dock_hub_reset,
+				"dock_hub_reset");
+	if (ret)
+		return ret;
+
+	dock->dock_eth_reset = of_get_named_gpio(node,
+						 "qti,dock-eth-reset-gpio", 0);
+	if (dock->dock_eth_reset < 0) {
+		dev_err(dock->dev, "unable to get dock-eth-reset-gpio\n");
+		return dock->dock_eth_reset;
+	}
+
+	ret = devm_gpio_request(dock->dev, dock->dock_eth_reset,
+				"dock_eth_reset");
+	if (ret)
+		return ret;
+
+	dock->dock_enable = of_get_named_gpio(node, "qti,dock-enable-gpio", 0);
+	if (dock->dock_enable < 0) {
+		dev_err(dock->dev, "unable to get dock-enable-gpio\n");
+		return dock->dock_enable;
+	}
+
+	ret = devm_gpio_request(dock->dev, dock->dock_enable, "dock_enable");
+	if (ret)
+		return ret;
+
+	schedule_work(&dock->dock_work);
+	device_init_wakeup(dock->dev, true);
+	enable_irq_wake(gpio_to_irq(dock->dock_detect));
+
+	return 0;
+}
+
+static int apq8084_dock_remove(struct platform_device *pdev)
+{
+	struct apq8084_dock *dock = platform_get_drvdata(pdev);
+
+	disable_irq_wake(gpio_to_irq(dock->dock_detect));
+	cancel_work_sync(&dock->dock_work);
+
+	return 0;
+}
+
+static struct of_device_id of_match_table[] = {
+	{       .compatible = "qti,apq8084-dock",
+	}
+};
+
+static struct platform_driver apq8084_dock_driver = {
+	.driver         = {
+		.name   = "apq8084-dock-driver",
+		.of_match_table = of_match_table,
+	},
+	.probe          = apq8084_dock_probe,
+	.remove		= apq8084_dock_remove,
+};
+
+module_platform_driver(apq8084_dock_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("QTI APQ8084 Docking Station driver");