First Commit

libraries/ssd1306/tools/kernelmod/ssd1306_main.c

@@ -0,0 +1,246 @@
+/*
+    MIT License
+
+    Copyright (C) 2018, Alexey Dynda
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in all
+    copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+    SOFTWARE.
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/string.h>
+
+#include "ssd1306.h"
+#include "intf/ssd1306_interface.h"
+#include "intf/i2c/ssd1306_i2c.h"
+#include "font6x8.h"
+
+#define DEVICE_CLASS_NAME "ssd1306_lcd"
+
+static int bus = 1;
+static int addr = 0x3C;
+static struct i2c_client *s_client = NULL;
+static struct ssd1306_data *s_data = NULL;
+//static struct class *ssd1306_class = NULL;
+
+module_param(bus, int, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+module_param(addr, int, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+
+MODULE_PARM_DESC(bus, " I2C Bus number, default 1");
+MODULE_PARM_DESC(addr, " I2C device address, default 0x3C");
+
+struct ssd1306_data {
+	struct mutex lock;
+	u8 index;
+	/// According to https://www.kernel.org/doc/Documentation/i2c/dev-interface
+	/// block buffers need not be longer than 32 bytes
+	u8 data[24];
+};
+
+
+static void ssd1306_smbus_end(void);
+
+static void ssd1306_smbus_start(void) {
+	s_data->index = 0;
+}
+
+static void ssd1306_smbus_send(u8 data) {
+	if (s_data->index >= sizeof(s_data->data)) {
+		ssd1306_smbus_end();
+		ssd1306_smbus_start();
+		s_data->data[0] = 0x40;
+		s_data->index++;
+	}
+	s_data->data[s_data->index] = data;
+	s_data->index++;
+}
+
+static void ssd1306_smbus_send_bytes(const u8 *buffer, u16 size)
+{
+	while (size--) {
+		ssd1306_smbus_send(*buffer);
+		buffer++;
+	}
+}
+
+static void ssd1306_smbus_end(void) {
+	if (s_data->index) {
+		i2c_smbus_write_i2c_block_data(s_client, s_data->data[0], s_data->index - 1, &s_data->data[1]);
+		s_data->index=0;
+	}
+}
+
+static void ssd1306_smbus_close(void) {
+}
+
+
+static ssize_t show_commands(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+//	struct ssd1306_data *data = i2c_get_clientdata(to_i2c_client(dev));
+	return sprintf(buf, 	"clear\n"
+				"pixel x,y\n"
+	);
+}
+
+static ssize_t execute_command(struct device *dev,
+			       struct device_attribute *attr,
+			       const char *buf, size_t count)
+{
+	char cmd[16];
+	s_client = to_i2c_client(dev);
+	s_data = i2c_get_clientdata(s_client);
+
+	mutex_lock(&s_data->lock);
+	sscanf(buf, "%15s", cmd);
+	if (!strcmp(cmd, "clear"))
+		ssd1306_clearScreen();
+	else if (!strcmp(cmd, "pixel")) {
+		int x, y;
+		sscanf(&buf[strlen(cmd) + 1], "%d,%d", &x, &y);
+		ssd1306_putPixel(x,y);
+	}
+	mutex_unlock(&s_data->lock);
+	return count;
+}
+
+static DEVICE_ATTR(command, S_IWUSR | S_IWGRP | S_IRUGO, show_commands, execute_command);
+
+static struct attribute *ssd1306_attributes[] = {
+	&dev_attr_command.attr,
+	NULL
+};
+
+static const struct attribute_group ssd1306_attr_group = {
+	.attrs = ssd1306_attributes,
+};
+
+static int ssd1306_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct ssd1306_data *data;
+	int err;
+
+	data = devm_kzalloc(&client->dev, sizeof(struct ssd1306_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, data);
+	mutex_init(&data->lock);
+	s_data = data;
+	ssd1306_startTransmission = ssd1306_smbus_start;
+	ssd1306_endTransmission = ssd1306_smbus_end;
+	ssd1306_sendByte = ssd1306_smbus_send;
+	ssd1306_sendBytes = ssd1306_smbus_send_bytes;
+	ssd1306_closeInterface = ssd1306_smbus_close;
+
+	mutex_lock(&data->lock);
+	s_client = client;
+	ssd1306_128x64_init();
+	ssd1306_fillScreen(0x00);
+	ssd1306_setFixedFont(ssd1306xled_font6x8);
+	ssd1306_printFixed (0,  8, "Line 1. text", 0); // STYLE_NORMAL
+	mutex_unlock(&data->lock);
+
+
+//	ssd1306_class = class_create(THIS_MODULE, DEVICE_CLASS_NAME);
+	/* Register sysfs hooks */
+	err = sysfs_create_group(&client->dev.kobj, &ssd1306_attr_group);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int ssd1306_remove(struct i2c_client *client)
+{
+//	struct ssd1306_data *data = i2c_get_clientdata(client);
+	sysfs_remove_group(&client->dev.kobj, &ssd1306_attr_group);
+	return 0;
+}
+
+
+static const struct i2c_device_id ssd1306_device_id[] = {
+	{ "ssd1306", 0 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, ssd1306_device_id);
+
+static struct i2c_driver ssd1306_driver = {
+	.probe = ssd1306_probe,
+	.remove = ssd1306_remove,
+	.id_table = ssd1306_device_id,
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "ssd1306"
+	},
+};
+
+
+static int __init ssd1306_driver_init(void)
+{
+	int ret;
+	struct i2c_adapter *adapter;
+	struct i2c_board_info board_info = {
+		.type = "ssd1306",
+		.addr = addr,
+
+	};
+	adapter = i2c_get_adapter(bus);
+	if (!adapter)
+		return -EINVAL;
+	s_client = i2c_new_device(adapter, &board_info);
+	if (!s_client) {
+		i2c_put_adapter(adapter);
+		return -EINVAL;
+	}
+	ret = i2c_add_driver(&ssd1306_driver);
+	if (ret) {
+		i2c_put_adapter(adapter);
+		return ret;
+	}
+	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) {
+		i2c_put_adapter(adapter);
+		dev_err(&s_client->dev, "i2c bus error\n");
+        	return -ENODEV;
+	}
+	i2c_put_adapter(adapter);
+	dev_info(&s_client->dev, "registered ssd1306\n");
+	return ret;
+}
+
+static void __exit ssd1306_driver_exit(void)
+{
+	if (s_client)
+		i2c_unregister_device(s_client);
+	i2c_del_driver(&ssd1306_driver);
+}
+
+MODULE_LICENSE("Dual MIT/GPL");
+MODULE_AUTHOR("Aleksei Dynda <alexey.dynda@gmail.com>");
+MODULE_DESCRIPTION("ssd1306 oled control driver");
+
+module_init(ssd1306_driver_init);
+module_exit(ssd1306_driver_exit);