--- /dev/null
+/*
+ * Microcontroller Message Bus
+ *
+ * Copyright (c) 2009 Michael Buesch <mb@bu3sch.de>
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include "ucmb.h"
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
+#include <linux/fs.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_gpio.h>
+#include <linux/spi/spi_bitbang.h>
+#include <linux/gfp.h>
+
+
+#define PFX "ucmb: "
+
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Microcontroller Message Bus");
+MODULE_AUTHOR("Michael Buesch");
+
+
+struct ucmb {
+ /* Misc character device driver */
+ struct miscdevice mdev;
+ struct file_operations mdev_fops;
+
+ /* SPI driver */
+ struct spi_device *sdev;
+
+ /* SPI-GPIO driver */
+ struct spi_gpio_platform_data spi_gpio_pdata;
+ struct platform_device spi_gpio_pdev;
+};
+
+static int ucmb_spi_busnum_count = 1337;
+
+
+static struct ucmb_platform_data ucmb_list[] = {
+ { //FIXME don't define it here.
+ .name = "ucmb",
+ .gpio_sck = 0,
+ .gpio_miso = 1,
+ .gpio_mosi = 2,
+ },
+};
+
+
+static int __devinit ucmb_spi_probe(struct spi_device *sdev)
+{
+ return 0;
+}
+
+static int __devexit ucmb_spi_remove(struct spi_device *sdev)
+{
+ return 0;
+}
+
+static struct spi_driver ucmb_spi_driver = {
+ .driver = {
+ .name = "ucmb",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+ .probe = ucmb_spi_probe,
+ .remove = __devexit_p(ucmb_spi_remove),
+};
+
+static inline struct ucmb * filp_to_ucmb(struct file *filp)
+{
+ return container_of(filp->f_op, struct ucmb, mdev_fops);
+}
+
+/* FIXME offp */
+static ssize_t ucmb_read(struct file *filp, char __user *user_buf,
+ size_t size, loff_t *offp)
+{
+ struct ucmb *ucmb = filp_to_ucmb(filp);
+ u8 *buf;
+ int err;
+
+ err = -E2BIG;
+ if (size > PAGE_SIZE)
+ goto out;
+
+ err = -ENOMEM;
+ buf = (char *)__get_free_page(GFP_KERNEL);
+ if (!buf)
+ goto out;
+
+ err = spi_read(ucmb->sdev, buf, size);
+ if (err)
+ goto out_free;
+
+ err = -EFAULT;
+ if (copy_to_user(user_buf, buf, size))
+ goto out_free;
+
+ err = 0;
+
+out_free:
+ __free_page((unsigned long)buf);
+out:
+ return err ? err : size;
+}
+
+/* FIXME offp */
+static ssize_t ucmb_write(struct file *filp, const char __user *user_buf,
+ size_t size, loff_t *offp)
+{
+ struct ucmb *ucmb = filp_to_ucmb(filp);
+ u8 *buf;
+ int err;
+
+ err = -ENOMEM;
+ buf = (char *)__get_free_page(GFP_KERNEL);
+ if (!buf)
+ goto out;
+
+ size = min(PAGE_SIZE, size);
+ err = -EFAULT;
+ if (copy_from_user(buf, user_buf, size))
+ goto out_free;
+
+ err = spi_write(ucmb->sdev, buf, size);
+
+out_free:
+ __free_page((unsigned long)buf);
+out:
+ return err ? err : size;
+}
+
+static int __devinit ucmb_probe(struct platform_device *pdev)
+{
+ struct ucmb_platform_data *pdata;
+ struct ucmb *ucmb;
+ int err;
+ const int bus_num = ucmb_spi_busnum_count++;
+ struct spi_bitbang *bb;
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -ENXIO;
+
+ ucmb = kzalloc(sizeof(struct ucmb), GFP_KERNEL);
+ if (!ucmb)
+ return -ENOMEM;
+
+ /* Create the SPI GPIO bus master. */
+
+#ifdef CONFIG_SPI_GPIO_MODULE
+ err = request_module("spi_gpio");
+ if (err)
+ printk(KERN_WARNING PFX "Failed to request spi_gpio module\n");
+#endif /* CONFIG_SPI_GPIO_MODULE */
+
+ ucmb->spi_gpio_pdata.sck = pdata->gpio_sck;
+ ucmb->spi_gpio_pdata.mosi = pdata->gpio_mosi;
+ ucmb->spi_gpio_pdata.miso = pdata->gpio_miso;
+ ucmb->spi_gpio_pdata.num_chipselect = 1;
+
+ ucmb->spi_gpio_pdev.name = "spi_gpio";
+ ucmb->spi_gpio_pdev.id = bus_num;
+ ucmb->spi_gpio_pdev.dev.platform_data = &ucmb->spi_gpio_pdata;
+
+ err = platform_device_register(&ucmb->spi_gpio_pdev);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to register SPI-GPIO platform device\n");
+ goto err_free_ucmb;
+ }
+ bb = platform_get_drvdata(&ucmb->spi_gpio_pdev);
+ if (!bb || !bb->master) {
+ printk(KERN_ERR PFX "No bitbanged master device found.\n");
+ goto err_unreg_spi_gpio_pdev;
+ }
+
+ /* Create the SPI device. */
+
+ ucmb->sdev = spi_alloc_device(bb->master);
+ if (!ucmb->sdev) {
+ printk(KERN_ERR PFX "Failed to allocate SPI device\n");
+ goto err_unreg_spi_gpio_pdev;
+ }
+ ucmb->sdev->max_speed_hz = 5000000;
+ ucmb->sdev->chip_select = 0;
+ ucmb->sdev->mode = SPI_MODE_0;
+ strlcpy(ucmb->sdev->modalias, "ucmb", /* We are the SPI driver. */
+ sizeof(ucmb->sdev->modalias));
+ ucmb->sdev->controller_data = (void *)SPI_GPIO_NO_CHIPSELECT;
+ err = spi_add_device(ucmb->sdev);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to add SPI device\n");
+ goto err_free_spi_device;
+ }
+
+ /* Create the Misc char device. */
+
+ ucmb->mdev.minor = MISC_DYNAMIC_MINOR;
+ ucmb->mdev.name = pdata->name;
+ ucmb->mdev.parent = &pdev->dev;
+ ucmb->mdev_fops.read = ucmb_read;
+ ucmb->mdev_fops.write = ucmb_write;
+ ucmb->mdev.fops = &ucmb->mdev_fops;
+
+ err = misc_register(&ucmb->mdev);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to register miscdev %s\n",
+ ucmb->mdev.name);
+ goto err_unreg_spi_device;
+ }
+
+ platform_set_drvdata(pdev, ucmb);
+
+ printk(KERN_INFO PFX "Registered message bus \"%s\"\n", pdata->name);
+
+ return 0;
+
+err_unreg_spi_device:
+ spi_unregister_device(ucmb->sdev);
+err_free_spi_device:
+ spi_dev_put(ucmb->sdev);
+err_unreg_spi_gpio_pdev:
+ platform_device_unregister(&ucmb->spi_gpio_pdev);
+err_free_ucmb:
+ kfree(ucmb);
+
+ return err;
+}
+
+static int __devexit ucmb_remove(struct platform_device *pdev)
+{
+ struct ucmb *ucmb = platform_get_drvdata(pdev);
+ int err;
+
+ err = misc_deregister(&ucmb->mdev);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to unregister miscdev %s\n",
+ ucmb->mdev.name);
+ }
+ spi_unregister_device(ucmb->sdev);
+ spi_dev_put(ucmb->sdev);
+ platform_device_unregister(&ucmb->spi_gpio_pdev);
+
+ kfree(ucmb);
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+static struct platform_driver ucmb_driver = {
+ .driver = {
+ .name = "ucmb",
+ .owner = THIS_MODULE,
+ },
+ .probe = ucmb_probe,
+ .remove = __devexit_p(ucmb_probe),
+};
+
+static int ucmb_modinit(void)
+{
+ struct ucmb_platform_data *pdata;
+ struct platform_device *pdev;
+ int err, i;
+
+ printk(KERN_INFO "Microcontroller message bus driver\n");
+
+ err = platform_driver_register(&ucmb_driver);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to register platform driver\n");
+ return err;
+ }
+ err = spi_register_driver(&ucmb_spi_driver);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to register SPI driver\n");
+ platform_driver_unregister(&ucmb_driver);
+ return err;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(ucmb_list); i++) {
+ pdata = &ucmb_list[i];
+
+ pdev = platform_device_alloc("ucmb", i);
+ if (!pdev) {
+ printk(KERN_ERR PFX "Failed to allocate platform device.\n");
+ break;
+ }
+ err = platform_device_add_data(pdev, pdata, sizeof(*pdata));
+ if (err) {
+ printk(KERN_ERR PFX "Failed to add platform data.\n");
+ platform_device_put(pdev);
+ break;
+ }
+ err = platform_device_add(pdev);
+ if (err) {
+ printk(KERN_ERR PFX "Failed to register platform device.\n");
+ platform_device_put(pdev);
+ break;
+ }
+ pdata->pdev = pdev;
+ }
+
+ return 0;
+}
+module_init(ucmb_modinit);
+
+static void ucmb_modexit(void)
+{
+ struct ucmb_platform_data *pdata;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ucmb_list); i++) {
+ pdata = &ucmb_list[i];
+
+ if (pdata->pdev) {
+ platform_device_unregister(pdata->pdev);
+ platform_device_put(pdata->pdev);
+ }
+ }
+ spi_unregister_driver(&ucmb_spi_driver);
+ platform_driver_unregister(&ucmb_driver);
+}
+module_exit(ucmb_modexit);
projects / openwrt / svn-archive / archive.git / commitdiff