input: keyboard: rpmsg-keys: add rpmsg-keys driver

Add rpmsg-keys driver for i.mx7ulp.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>

4 files changed, 355 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/input/rpmsg-keys.txt b/Documentation/devicetree/bindings/input/rpmsg-keys.txt
new file mode 100644
index 000000000000..d9279802cc9c
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/rpmsg-keys.txt
@@ -0,0 +1,33 @@
+Device-Tree bindings for input/keyboard/rpmsg-keys.c keys driver over
+rpmsg. On i.mx7ULP keys are connected on M4 side, so rpmsg-keys driver
+needed to get the key status from M4 side by rpmsg.
+
+Required properties:
+	- compatible = "fsl,rpmsg-keys";
+
+Each button/key looked as the sub node:
+Required properties:
+	- label: the key name
+	- linux,code: the key value defined in
+		include/dt-bindings/input/input.h
+Optional property:
+	- rpmsg-key,wakeup: wakeup feature, the keys can wakeup from
+	suspend if the keys with this property pressed.
+
+Example nodes:
+	rpmsg_keys: rpmsg-keys {
+		compatible = "fsl,rpmsg-keys";
+
+		volume-up {
+			label = "Volume Up";
+			rpmsg-key,wakeup;
+			linux,code = <KEY_VOLUMEUP>;
+		};
+
+		volume-down {
+			label = "Volume Down";
+			rpmsg-key,wakeup;
+			linux,code = <KEY_VOLUMEDOWN>;
+		};
+	};
+
diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 8911bc2ec42a..41e2e0dc3efb 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -448,6 +448,17 @@ config KEYBOARD_MPR121
 	  To compile this driver as a module, choose M here: the
 	  module will be called mpr121_touchkey.
 
+config KEYBOARD_RPMSG
+       tristate "i.MX Rpmsg Keys Driver"
+       depends on (SOC_IMX7ULP)
+       depends on RPMSG
+       depends on OF
+       help
+         This is rpmsg keys driver on i.mx7ulp, because some keys located
+         in M4 side.
+
+
+
 config KEYBOARD_SNVS_PWRKEY
 	tristate "IMX SNVS Power Key Driver"
 	depends on ARCH_MXC || COMPILE_TEST
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 9510325c0c5d..e8aa02b4733c 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -54,6 +54,7 @@ obj-$(CONFIG_KEYBOARD_PXA930_ROTARY)	+= pxa930_rotary.o
 obj-$(CONFIG_KEYBOARD_QT1050)           += qt1050.o
 obj-$(CONFIG_KEYBOARD_QT1070)           += qt1070.o
 obj-$(CONFIG_KEYBOARD_QT2160)		+= qt2160.o
+obj-$(CONFIG_KEYBOARD_RPMSG)		+= rpmsg-keys.o
 obj-$(CONFIG_KEYBOARD_SAMSUNG)		+= samsung-keypad.o
 obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
 obj-$(CONFIG_KEYBOARD_SNVS_PWRKEY)	+= snvs_pwrkey.o
diff --git a/drivers/input/keyboard/rpmsg-keys.c b/drivers/input/keyboard/rpmsg-keys.c
new file mode 100644
index 000000000000..f6012e87f9a6
--- /dev/null
+++ b/drivers/input/keyboard/rpmsg-keys.c
@@ -0,0 +1,310 @@
+/*
+ * Copyright 2017 NXP
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/err.h>
+#include <linux/slab.h>
+#include <linux/imx_rpmsg.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_qos.h>
+#include <linux/rpmsg.h>
+#include <linux/uaccess.h>
+#include <linux/virtio.h>
+
+#define RPMSG_TIMEOUT 1000
+
+enum key_cmd_type {
+	KEY_RPMSG_SETUP,
+	KEY_RPMSG_REPLY,
+	KEY_RPMSG_NOTIFY,
+};
+
+enum keys_type {
+	KEY_PRESS = 1,
+	KEY_RELEASE,
+	KEY_BOTH,
+};
+
+struct key_rpmsg_data {
+	struct imx_rpmsg_head header;
+	u8 key_index;
+	union {
+		u8 event;
+		u8 retcode;
+	};
+	u8 wakeup;
+} __attribute__((packed));
+
+struct rpmsg_keys_button {
+	unsigned int code;
+	enum keys_type type;
+	int wakeup;
+	struct input_dev *input;
+};
+
+struct rpmsg_keys_drvdata {
+	struct input_dev *input;
+	struct rpmsg_device *rpdev;
+	struct device *dev;
+	struct key_rpmsg_data *msg;
+	bool ack;
+	struct pm_qos_request pm_qos_req;
+	struct delayed_work keysetup_work;
+	struct completion cmd_complete;
+	int nbuttons;
+	struct rpmsg_keys_button buttons[0];
+};
+
+static struct rpmsg_keys_drvdata *keys_rpmsg;
+
+static int key_send_message(struct key_rpmsg_data *msg,
+			struct rpmsg_keys_drvdata *info, bool ack)
+{
+	int err;
+
+	if (!info->rpdev) {
+		dev_dbg(info->dev,
+			"rpmsg channel not ready, m4 image ready?\n");
+		return -EINVAL;
+	}
+
+	pm_qos_add_request(&info->pm_qos_req,
+			PM_QOS_CPU_DMA_LATENCY, 0);
+
+	if (ack) {
+		info->ack = true;
+		reinit_completion(&info->cmd_complete);
+	}
+
+	err = rpmsg_send(info->rpdev->ept, (void *)msg,
+			    sizeof(struct key_rpmsg_data));
+	if (err) {
+		dev_err(&info->rpdev->dev, "rpmsg_send failed: %d\n", err);
+		goto err_out;
+	}
+
+	if (ack) {
+		err = wait_for_completion_timeout(&info->cmd_complete,
+					msecs_to_jiffies(RPMSG_TIMEOUT));
+		if (!err) {
+			dev_err(&info->rpdev->dev, "rpmsg_send timeout!\n");
+			err = -ETIMEDOUT;
+			goto err_out;
+		}
+
+		if (info->msg->retcode != 0) {
+			dev_err(&info->rpdev->dev, "rpmsg not ack %d!\n",
+				info->msg->retcode);
+			err = -EINVAL;
+			goto err_out;
+		}
+
+		err = 0;
+	}
+
+err_out:
+	info->ack = true;
+	pm_qos_remove_request(&info->pm_qos_req);
+
+	return err;
+}
+
+static int keys_rpmsg_cb(struct rpmsg_device *rpdev,
+	void *data, int len, void *priv, u32 src)
+{
+	struct key_rpmsg_data *msg = (struct key_rpmsg_data *)data;
+
+	if (msg->header.type == KEY_RPMSG_REPLY) {
+		keys_rpmsg->msg = msg;
+		complete(&keys_rpmsg->cmd_complete);
+		return 0;
+	} else if (msg->header.type == KEY_RPMSG_NOTIFY) {
+		keys_rpmsg->msg = msg;
+		keys_rpmsg->ack = false;
+	} else
+		dev_err(&keys_rpmsg->rpdev->dev, "wrong command type!\n");
+
+	input_event(keys_rpmsg->input, EV_KEY, msg->key_index, msg->event);
+	input_sync(keys_rpmsg->input);
+
+	return 0;
+}
+
+static void keys_init_handler(struct work_struct *work)
+{
+	struct key_rpmsg_data msg;
+	int i;
+
+	/* setup keys */
+	for (i = 0; i < keys_rpmsg->nbuttons; i++) {
+		struct rpmsg_keys_button *button = &keys_rpmsg->buttons[i];
+
+		msg.header.cate = IMX_RPMSG_KEY;
+		msg.header.major = IMX_RMPSG_MAJOR;
+		msg.header.minor = IMX_RMPSG_MINOR;
+		msg.header.type = KEY_RPMSG_SETUP;
+		msg.header.cmd = 0;
+		msg.key_index = button->code;
+		msg.wakeup = button->wakeup;
+		msg.event = button->type;
+		if (key_send_message(&msg, keys_rpmsg, true))
+			dev_err(&keys_rpmsg->rpdev->dev,
+				"key %d setup failed!\n", button->code);
+	}
+}
+
+static int keys_rpmsg_probe(struct rpmsg_device *rpdev)
+{
+	keys_rpmsg->rpdev = rpdev;
+
+	dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
+			rpdev->src, rpdev->dst);
+
+	init_completion(&keys_rpmsg->cmd_complete);
+
+	INIT_DELAYED_WORK(&keys_rpmsg->keysetup_work,
+				keys_init_handler);
+	schedule_delayed_work(&keys_rpmsg->keysetup_work,
+			msecs_to_jiffies(100));
+
+	return 0;
+}
+
+static struct rpmsg_device_id keys_rpmsg_id_table[] = {
+	{ .name	= "rpmsg-keypad-channel" },
+	{ },
+};
+
+static struct rpmsg_driver keys_rpmsg_driver = {
+	.drv.name	= "key_rpmsg",
+	.drv.owner	= THIS_MODULE,
+	.id_table	= keys_rpmsg_id_table,
+	.probe		= keys_rpmsg_probe,
+	.callback	= keys_rpmsg_cb,
+};
+
+static struct rpmsg_keys_drvdata *
+rpmsg_keys_get_devtree_pdata(struct device *dev)
+{
+	struct device_node *node, *pp;
+	struct rpmsg_keys_drvdata *ddata;
+	struct rpmsg_keys_button *button;
+	int nbuttons;
+	int i;
+
+	node = dev->of_node;
+	if (!node)
+		return ERR_PTR(-ENODEV);
+
+	nbuttons = of_get_child_count(node);
+	if (nbuttons == 0)
+		return ERR_PTR(-ENODEV);
+
+	ddata = devm_kzalloc(dev,
+			     sizeof(*ddata) + nbuttons *
+			     sizeof(struct rpmsg_keys_button),
+			     GFP_KERNEL);
+	if (!ddata)
+		return ERR_PTR(-ENOMEM);
+
+	ddata->nbuttons = nbuttons;
+
+	i = 0;
+	for_each_child_of_node(node, pp) {
+		button = &ddata->buttons[i++];
+
+		if (of_property_read_u32(pp, "linux,code", &button->code)) {
+			dev_err(dev, "Button without keycode: 0x%x\n",
+				button->code);
+			return ERR_PTR(-EINVAL);
+		}
+
+		button->wakeup = !!of_get_property(pp, "rpmsg-key,wakeup",
+							NULL);
+		button->type = KEY_BOTH;
+	}
+
+	return ddata;
+}
+
+static int rpmsg_keys_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rpmsg_keys_drvdata *ddata;
+	int i, error;
+	struct input_dev *input;
+
+	ddata = rpmsg_keys_get_devtree_pdata(dev);
+	if (IS_ERR(ddata))
+		return PTR_ERR(ddata);
+
+	input = devm_input_allocate_device(dev);
+	if (!input) {
+		dev_err(dev, "failed to allocate input device\n");
+		return -ENOMEM;
+	}
+
+	ddata->input = input;
+
+	keys_rpmsg = ddata;
+	platform_set_drvdata(pdev, ddata);
+
+	input->name = pdev->name;
+	input->phys = "rpmsg-keys/input0";
+	input->dev.parent = &pdev->dev;
+
+	input->id.bustype = BUS_HOST;
+
+	for (i = 0; i < ddata->nbuttons; i++) {
+		struct rpmsg_keys_button *button = &ddata->buttons[i];
+
+		input_set_capability(input, EV_KEY, button->code);
+	}
+
+	error = input_register_device(input);
+	if (error) {
+		dev_err(dev, "Unable to register input device, error: %d\n",
+			error);
+		goto err_out;
+	}
+
+	return register_rpmsg_driver(&keys_rpmsg_driver);
+err_out:
+	return error;
+}
+
+static const struct of_device_id rpmsg_keys_of_match[] = {
+	{ .compatible = "fsl,rpmsg-keys", },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(of, rpmsg_keys_of_match);
+
+static struct platform_driver rpmsg_keys_device_driver = {
+	.probe		= rpmsg_keys_probe,
+	.driver		=  {
+		.name	= "rpmsg-keys",
+		.of_match_table = of_match_ptr(rpmsg_keys_of_match)
+	}
+};
+
+module_platform_driver(rpmsg_keys_device_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Robin Gong <yibin.gong@nxp.com>");
+MODULE_DESCRIPTION("Keyboard driver based on rpmsg");