diff options
Diffstat (limited to 'drivers/i2c-slave/i2c_slave_core.c')
| -rw-r--r-- | drivers/i2c-slave/i2c_slave_core.c | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/drivers/i2c-slave/i2c_slave_core.c b/drivers/i2c-slave/i2c_slave_core.c new file mode 100644 index 000000000000..4d3a21a5f45f --- /dev/null +++ b/drivers/i2c-slave/i2c_slave_core.c @@ -0,0 +1,359 @@ +/* + * Copyright 2007-2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/module.h> +#include <linux/device.h> +#include <asm/uaccess.h> +#include "i2c_slave_device.h" + +int i2c_slave_major; + +static ssize_t i2c_slave_read(struct file *fd, char __user *buf, size_t len, + loff_t *ptr) +{ + i2c_slave_device_t *dev; + void *kbuf; + int ret; + + if (len == 0) + return 0; + + kbuf = kmalloc(len, GFP_KERNEL); + if (!kbuf) { + ret = -ENOMEM; + goto error0; + } + + dev = (i2c_slave_device_t *) fd->private_data; + if (!dev) { + ret = -ENODEV; + goto error1; + } + + ret = i2c_slave_device_read(dev, len, kbuf); + if (ret <= 0 || copy_to_user(buf, kbuf, len)) { + ret = -EFAULT; + } + + error1: + kfree(kbuf); + error0: + return ret; +} + +static ssize_t i2c_slave_write(struct file *fd, const char __user *buf, + size_t len, loff_t *ptr) +{ + i2c_slave_device_t *dev; + void *kbuf; + int ret; + + if (len == 0) + return 0; + + kbuf = kmalloc(len, GFP_KERNEL); + if (!kbuf) { + ret = -ENOMEM; + goto error0; + } + if (copy_from_user(kbuf, buf, len)) { + ret = -EFAULT; + goto error1; + } + + dev = (i2c_slave_device_t *) fd->private_data; + if (!dev) { + ret = -ENODEV; + goto error1; + } + + ret = i2c_slave_device_write(dev, len, (u8 *) kbuf); + + error1: + kfree(kbuf); + error0: + return ret; +} + +static int i2c_slave_ioctl(struct inode *inode, struct file *fd, + unsigned code, unsigned long value) +{ + /*todo */ + return 0; +} + +static int i2c_slave_open(struct inode *inode, struct file *fd) +{ + int ret; + unsigned int id; + i2c_slave_device_t *dev; + id = iminor(inode); + + if (id >= I2C_SLAVE_DEVICE_MAX) { + ret = -ENODEV; + goto error; + } + + dev = i2c_slave_device_find(id); + if (!dev) { + ret = -ENODEV; + goto error; + } + + i2c_slave_rb_clear(dev->receive_buffer); + i2c_slave_rb_clear(dev->send_buffer); + + if (i2c_slave_device_start(dev)) { + ret = -EBUSY; + goto error; + } + + fd->private_data = (void *)dev; + ret = 0; + + error: + return ret; +} + +static int i2c_slave_release(struct inode *inode, struct file *fd) +{ + int ret; + unsigned int id; + i2c_slave_device_t *dev; + id = iminor(inode); + + if (id >= I2C_SLAVE_DEVICE_MAX) { + ret = -ENODEV; + goto error; + } + + dev = i2c_slave_device_find(id); + if (!dev) { + ret = -ENODEV; + goto error; + } + + if (i2c_slave_device_stop(dev)) { + ret = -EBUSY; + goto error; + } + + ret = 0; + + error: + return ret; +} + +static const struct file_operations i2c_slave_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = i2c_slave_read, + .write = i2c_slave_write, + .ioctl = i2c_slave_ioctl, + .open = i2c_slave_open, + .release = i2c_slave_release, +}; + +static int i2c_slave_bus_match(struct device *dev, struct device_driver *drv) +{ + return 0; +} + +/* +static int i2c_slave_bus_probe(struct device *dev) +{ + struct device_driver *driver = dev->driver; + + if (driver) { + return driver->probe(dev); + } else { + dev_err(dev, "%s: no driver\n", __func__); + return -ENODEV; + } +} +*/ + +static int i2c_slave_bus_remove(struct device *dev) +{ + struct device_driver *driver = dev->driver; + + if (driver) { + if (!driver->remove) { + return 0; + } else { + return driver->remove(dev); + } + } else { + + dev_err(dev, "%s: no driver\n", __func__); + return -ENODEV; + } +} + +static void i2c_slave_bus_shutdown(struct device *dev) +{ + struct device_driver *driver = dev->driver; + + if (driver) { + + driver->shutdown(dev); + } else { + + dev_err(dev, "%s: no driver\n", __func__); + return; + } +} +static int i2c_slave_bus_suspend(struct device *dev, pm_message_t state) +{ + struct device_driver *driver = dev->driver; + + if (driver) { + + if (!driver->suspend) { + return 0; + } else { + return driver->suspend(dev, state); + } + } else { + + dev_err(dev, "%s: no driver\n", __func__); + return -ENODEV; + } +} + +static int i2c_slave_bus_resume(struct device *dev) +{ + struct device_driver *driver = dev->driver; + + if (driver) { + + if (!driver->resume) { + return 0; + } else { + return driver->resume(dev); + } + } else { + + dev_err(dev, "%s: no driver\n", __func__); + return -ENODEV; + } +} + +struct bus_type i2c_slave_bus_type = { + .name = "i2c-slave", + .match = i2c_slave_bus_match, + .remove = i2c_slave_bus_remove, + .shutdown = i2c_slave_bus_shutdown, + .suspend = i2c_slave_bus_suspend, + .resume = i2c_slave_bus_resume, +}; + +EXPORT_SYMBOL_GPL(i2c_slave_bus_type); + +static int i2c_slave_driver_probe(struct device *dev) +{ + return 0; +} + +static int i2c_slave_driver_remove(struct device *dev) +{ + return 0; +} + +static int i2c_slave_driver_shutdown(struct device *dev) +{ + return 0; +} + +static int i2c_slave_driver_suspend(struct device *dev, pm_message_t state) +{ + return 0; +} + +static int i2c_slave_driver_resume(struct device *dev) +{ + return 0; +} + +extern struct class *i2c_slave_class; + +static struct device_driver i2c_slave_driver = { + .name = "i2c-slave", + .owner = THIS_MODULE, + .bus = &i2c_slave_bus_type, + .probe = i2c_slave_driver_probe, + .remove = i2c_slave_driver_remove, + .shutdown = i2c_slave_driver_shutdown, + .suspend = i2c_slave_driver_suspend, + .resume = i2c_slave_driver_resume, +}; + +static int __init i2c_slave_dev_init(void) +{ + int ret; + + printk(KERN_INFO "i2c slave /dev entries driver\n"); + + ret = bus_register(&i2c_slave_bus_type); + if (ret) { + printk(KERN_ERR "%s: bus_register error\n", __func__); + goto out; + } + + i2c_slave_class = class_create(THIS_MODULE, "i2c-slave"); + if (IS_ERR(i2c_slave_class)) { + pr_err("%s: class_create error\n", __func__); + goto out_unreg_bus; + } + + i2c_slave_major = register_chrdev(0, "i2c-slave", &i2c_slave_fops); + if (i2c_slave_major <= 0) { + pr_err("%s: register_chrdev error\n", __func__); + goto out_unreg_class; + } + + ret = driver_register(&i2c_slave_driver); + if (ret) { + pr_err("%s: driver_register error\n", __func__); + goto out_unreg_chrdev; + } + + return 0; + + out_unreg_chrdev: + unregister_chrdev(i2c_slave_major, "i2c-slave"); + out_unreg_class: + class_destroy(i2c_slave_class); + out_unreg_bus: + bus_unregister(&i2c_slave_bus_type); + out: + pr_err("%s: init error\n", __func__); + return ret; +} + +static void __exit i2c_dev_exit(void) +{ + driver_unregister(&i2c_slave_driver); + class_destroy(i2c_slave_class); + unregister_chrdev(i2c_slave_major, "i2c-slave"); + bus_unregister(&i2c_slave_bus_type); +} + +module_init(i2c_slave_dev_init); +module_exit(i2c_dev_exit); + +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("I2C Slave Driver Core"); +MODULE_LICENSE("GPL"); |