ioc: kernel-driver: Create framework for serdev driver

ioc/kernel-driver/.gitignore

@@ -4,3 +4,5 @@
 modules.order
 Module.symvers
 *.pro.user
+.*
+*.a

ioc/kernel-driver/Makefile

@@ -1,12 +1,12 @@
-obj-m := lw35-ioc.o
+obj-m := lw35ioc.o
-KDIR := ~/projects/arm-linux/current
+KDIR := ~/projects/linux/opi-current
 PWD := $(shell pwd)
-default: lw35-ioc.ko
+default: lw35ioc.ko
-lw35-ioc.ko: lw35-ioc.c
+lw35ioc.ko: lw35ioc.c
-	$(MAKE) -C $(KDIR) SUBDIRS=$(PWD) modules
+	$(MAKE) -C $(KDIR) M=$(PWD)
 
-deploy: lw35-ioc.ko
+deploy: lw35ioc.ko
-	scp $< markus@opi:/home/markus/lw35-ioc/deploy
+	scp $< markus@opi:/home/markus/projects/lw35/deploy/
 
 clean:
 	rm -f ./*.o ./*.ko ./*.mod.c modules.order Module.symvers

ioc/kernel-driver/device-tree-opi-pc.dtb

@@ -1,28 +0,0 @@
-/*
-	Reading: https://www.kernel.org/doc/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
-*/
-
-&spi1 {
-	status = "okay";
-	lw35ioc@0 {
-		compatible = "brother,lw35ioc";
-		reg = <0x0>;
-		spi-max-frequency = <2000000>;
-		
-		pinctrl-names = "default";
-		pinctrl-0 = <&lw35ioc>;
-		data-gpios = <&pio 0 7 GPIO_ACTIVE_HIGH>; /* TODO: get real IO num */
-		
-		interrupt-parent = <&pio>;
-		interrupts = <52 2>;
-	};
-};
-
-&pio {
-	lmg6202ulyt_opc: lmg6202ulyt_pins {
-		pins = "PA7";
-		function = "gpio_out";
-		interrupt-controller;
-		#interrupt-cells = <1>;
-	};
-};

ioc/kernel-driver/device-tree-opi-pc.patch

@@ -0,0 +1,18 @@
+diff --git a/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts b/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts
+index 5aff8ecc66cb..c8201e79dff3 100644
+--- a/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts
++++ b/arch/arm/boot/dts/sun8i-h3-orangepi-pc.dts
+@@ -211,9 +211,12 @@
+ };
+ 
+ &uart1 {
++	status = "okay";
+ 	pinctrl-names = "default";
+ 	pinctrl-0 = <&uart1_pins>;
+-	status = "disabled";
++	lw35ioc@0 {
++		compatible = "brother,lw35";
++	};
+ };
+ 
+ &uart2 {

ioc/kernel-driver/lw35-ioc.c

@@ -1,78 +0,0 @@
-#include <linux/init.h>
-#include <linux/dma-mapping.h>
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/delay.h>
-#include <linux/spi/spi.h>
-#include <linux/of_device.h>
-#include <linux/gpio/consumer.h>
-#include <linux/interrupt.h>
-
-/*
- * irq in general: https://notes.shichao.io/lkd/ch7/
- * raspi irqs: http://morethanuser.blogspot.com/2013/04/raspberry-pi-gpio-interrupts-in-kernel.html
- * kdoc devtree irq: https://www.kernel.org/doc/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
- * GPIOD doc (including irq): https://www.kernel.org/doc/Documentation/gpio/consumer.txt
- */
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Markus Koch");
-MODULE_DESCRIPTION("LW35 I/O Controller Driver");
-MODULE_VERSION("0.1");
-
-static char *testparam = "param";
-module_param(testparam, charp, S_IRUGO);
-MODULE_PARM_DESC(testparam, "A test parameter");
-
-static struct of_device_id lw35ioc_dt_ids[] = {
-{ .compatible = "brother,lw35", },
-{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, lw35ioc_dt_ids);
-
-struct lw35ioc_priv {
-	struct spi_device *spi;
-	
-	// USER VARS HERE
-};
-
-static int lw35ioc_probe(struct spi_device *spi)
-{
-	struct lw35ioc_priv *priv = NULL;
-
-	printk(KERN_INFO "lw35ioc: probe\n");
-
-	priv = devm_kzalloc(&spi->dev,
-			    sizeof(struct lw35ioc_priv),
-			    GFP_KERNEL);
-	if (!priv)
-		return -ENOMEM;
-	spi_set_drvdata(spi, priv);
-
-	priv->spi = spi;
-
-	printk(KERN_INFO "lw35ioc: Loaded driver\n");
-
-	return 0;
-
-	// Error handlers go here
-}
-
-static int lw35ioc_remove(struct spi_device *spi)
-{
-	struct lw35ioc_priv *priv = spi_get_drvdata(spi);
-
-	return 0;
-}
-
-static struct spi_driver lw35ioc_driver = {
-	.probe = lw35ioc_probe,
-	.remove = lw35ioc_remove,
-	.driver = {
-		.name = "lw35ioc",
-		.owner = THIS_MODULE,
-		.of_match_table = lw35ioc_dt_ids,
-	},
-};
-module_spi_driver(lw35ioc_driver);
-

ioc/kernel-driver/lw35ioc.c

@@ -0,0 +1,102 @@
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/serdev.h>
+#include <linux/types.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Markus Koch");
+MODULE_DESCRIPTION("LW-35 I/O Controller Driver");
+MODULE_VERSION("0.1");
+
+static int debug_level = 0;
+module_param(debug_level, int, 0);
+MODULE_PARM_DESC(debug_level, "Debug level");
+
+static struct of_device_id lw35ioc_dt_ids[] = {
+{ .compatible = "brother,lw35", },
+{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, lw35ioc_dt_ids);
+
+struct lw35ioc_priv {
+	struct serdev_device *serdev;
+	
+	// USER VARS HERE
+};
+
+static int lw35ioc_receive_buf(struct serdev_device *serdev,
+				    const unsigned char *data,
+				    size_t count)
+{
+	dev_info(&serdev->dev, "RX: %c\n", data[0]);
+	return 1; // TODO: return proper value
+}
+
+static void lw35ioc_write_wakeup(struct serdev_device *serdev)
+{
+	dev_info(&serdev->dev, "Write wakeup\n");
+	// schedule work here
+}
+
+static struct serdev_device_ops lw35ioc_serdev_ops = {
+	.receive_buf = lw35ioc_receive_buf,
+	.write_wakeup = lw35ioc_write_wakeup,
+};
+
+static int lw35ioc_probe(struct serdev_device *serdev)
+{
+	struct lw35ioc_priv *priv = NULL;
+	int ret;
+	u32 speed = 9600;
+
+	printk(KERN_INFO "lw35ioc: probe\n");
+
+        priv = devm_kzalloc(&serdev->dev,
+                    sizeof(struct lw35ioc_priv),
+                    GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+	priv->serdev = serdev;
+	serdev_device_set_drvdata(serdev, priv);
+	serdev_device_set_client_ops(serdev, &lw35ioc_serdev_ops);
+
+	ret = serdev_device_open(serdev);
+	if (ret) {
+		dev_err(&serdev->dev, "Unable to open device.\n");
+		goto fail0;
+	}
+
+	speed = serdev_device_set_baudrate(serdev, speed);
+	dev_info(&serdev->dev, "Using baudrate: %u\n", speed);
+
+	dev_info(&serdev->dev, "Loaded driver\n");
+
+	return 0;
+
+fail0:
+	return ret;
+}
+
+static void lw35ioc_remove(struct serdev_device *serdev)
+{
+	struct lw35ioc_priv *priv = serdev_device_get_drvdata(serdev);
+	dev_info(&serdev->dev, "remove\n");
+	return;
+}
+
+static struct serdev_device_driver lw35ioc_driver = {
+	.probe = lw35ioc_probe,
+	.remove = lw35ioc_remove,
+	.driver = {
+		.name = "lw35ioc",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(lw35ioc_dt_ids),
+	},
+};
+
+module_serdev_device_driver(lw35ioc_driver);
+

ioc/kernel-driver/lw35ioc.pro

@@ -6,4 +6,4 @@ CONFIG -= qt
 INCLUDEPATH += /home/markus/projects/arm-linux/current/include
 
 SOURCES += \
-        lw35-ioc.c
+        lw35ioc.c