| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * SCR24x PCMCIA Smart Card Reader Driver |
| * |
| * Copyright (C) 2005-2006 TL Sudheendran |
| * Copyright (C) 2016 Lubomir Rintel |
| * |
| * Derived from "scr24x_v4.2.6_Release.tar.gz" driver by TL Sudheendran. |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/module.h> |
| #include <linux/delay.h> |
| #include <linux/cdev.h> |
| #include <linux/slab.h> |
| #include <linux/fs.h> |
| #include <linux/io.h> |
| #include <linux/uaccess.h> |
| |
| #include <pcmcia/cistpl.h> |
| #include <pcmcia/ds.h> |
| |
| #define CCID_HEADER_SIZE 10 |
| #define CCID_LENGTH_OFFSET 1 |
| #define CCID_MAX_LEN 271 |
| |
| #define SCR24X_DATA(n) (1 + n) |
| #define SCR24X_CMD_STATUS 7 |
| #define CMD_START 0x40 |
| #define CMD_WRITE_BYTE 0x41 |
| #define CMD_READ_BYTE 0x42 |
| #define STATUS_BUSY 0x80 |
| |
| struct scr24x_dev { |
| struct device *dev; |
| struct cdev c_dev; |
| unsigned char buf[CCID_MAX_LEN]; |
| int devno; |
| struct mutex lock; |
| struct kref refcnt; |
| u8 __iomem *regs; |
| }; |
| |
| #define SCR24X_DEVS 8 |
| static DECLARE_BITMAP(scr24x_minors, SCR24X_DEVS); |
| |
| static struct class *scr24x_class; |
| static dev_t scr24x_devt; |
| |
| static void scr24x_delete(struct kref *kref) |
| { |
| struct scr24x_dev *dev = container_of(kref, struct scr24x_dev, |
| refcnt); |
| |
| kfree(dev); |
| } |
| |
| static int scr24x_wait_ready(struct scr24x_dev *dev) |
| { |
| u_char status; |
| int timeout = 100; |
| |
| do { |
| status = ioread8(dev->regs + SCR24X_CMD_STATUS); |
| if (!(status & STATUS_BUSY)) |
| return 0; |
| |
| msleep(20); |
| } while (--timeout); |
| |
| return -EIO; |
| } |
| |
| static int scr24x_open(struct inode *inode, struct file *filp) |
| { |
| struct scr24x_dev *dev = container_of(inode->i_cdev, |
| struct scr24x_dev, c_dev); |
| |
| kref_get(&dev->refcnt); |
| filp->private_data = dev; |
| |
| return stream_open(inode, filp); |
| } |
| |
| static int scr24x_release(struct inode *inode, struct file *filp) |
| { |
| struct scr24x_dev *dev = filp->private_data; |
| |
| /* We must not take the dev->lock here as scr24x_delete() |
| * might be called to remove the dev structure altogether. |
| * We don't need the lock anyway, since after the reference |
| * acquired in probe() is released in remove() the chrdev |
| * is already unregistered and noone can possibly acquire |
| * a reference via open() anymore. */ |
| kref_put(&dev->refcnt, scr24x_delete); |
| return 0; |
| } |
| |
| static int read_chunk(struct scr24x_dev *dev, size_t offset, size_t limit) |
| { |
| size_t i, y; |
| int ret; |
| |
| for (i = offset; i < limit; i += 5) { |
| iowrite8(CMD_READ_BYTE, dev->regs + SCR24X_CMD_STATUS); |
| ret = scr24x_wait_ready(dev); |
| if (ret < 0) |
| return ret; |
| |
| for (y = 0; y < 5 && i + y < limit; y++) |
| dev->buf[i + y] = ioread8(dev->regs + SCR24X_DATA(y)); |
| } |
| |
| return 0; |
| } |
| |
| static ssize_t scr24x_read(struct file *filp, char __user *buf, size_t count, |
| loff_t *ppos) |
| { |
| struct scr24x_dev *dev = filp->private_data; |
| int ret; |
| int len; |
| |
| if (count < CCID_HEADER_SIZE) |
| return -EINVAL; |
| |
| if (mutex_lock_interruptible(&dev->lock)) |
| return -ERESTARTSYS; |
| |
| if (!dev->dev) { |
| ret = -ENODEV; |
| goto out; |
| } |
| |
| ret = scr24x_wait_ready(dev); |
| if (ret < 0) |
| goto out; |
| len = CCID_HEADER_SIZE; |
| ret = read_chunk(dev, 0, len); |
| if (ret < 0) |
| goto out; |
| |
| len += le32_to_cpu(*(__le32 *)(&dev->buf[CCID_LENGTH_OFFSET])); |
| if (len > sizeof(dev->buf)) { |
| ret = -EIO; |
| goto out; |
| } |
| ret = read_chunk(dev, CCID_HEADER_SIZE, len); |
| if (ret < 0) |
| goto out; |
| |
| if (len < count) |
| count = len; |
| |
| if (copy_to_user(buf, dev->buf, count)) { |
| ret = -EFAULT; |
| goto out; |
| } |
| |
| ret = count; |
| out: |
| mutex_unlock(&dev->lock); |
| return ret; |
| } |
| |
| static ssize_t scr24x_write(struct file *filp, const char __user *buf, |
| size_t count, loff_t *ppos) |
| { |
| struct scr24x_dev *dev = filp->private_data; |
| size_t i, y; |
| int ret; |
| |
| if (mutex_lock_interruptible(&dev->lock)) |
| return -ERESTARTSYS; |
| |
| if (!dev->dev) { |
| ret = -ENODEV; |
| goto out; |
| } |
| |
| if (count > sizeof(dev->buf)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| if (copy_from_user(dev->buf, buf, count)) { |
| ret = -EFAULT; |
| goto out; |
| } |
| |
| ret = scr24x_wait_ready(dev); |
| if (ret < 0) |
| goto out; |
| |
| iowrite8(CMD_START, dev->regs + SCR24X_CMD_STATUS); |
| ret = scr24x_wait_ready(dev); |
| if (ret < 0) |
| goto out; |
| |
| for (i = 0; i < count; i += 5) { |
| for (y = 0; y < 5 && i + y < count; y++) |
| iowrite8(dev->buf[i + y], dev->regs + SCR24X_DATA(y)); |
| |
| iowrite8(CMD_WRITE_BYTE, dev->regs + SCR24X_CMD_STATUS); |
| ret = scr24x_wait_ready(dev); |
| if (ret < 0) |
| goto out; |
| } |
| |
| ret = count; |
| out: |
| mutex_unlock(&dev->lock); |
| return ret; |
| } |
| |
| static const struct file_operations scr24x_fops = { |
| .owner = THIS_MODULE, |
| .read = scr24x_read, |
| .write = scr24x_write, |
| .open = scr24x_open, |
| .release = scr24x_release, |
| .llseek = no_llseek, |
| }; |
| |
| static int scr24x_config_check(struct pcmcia_device *link, void *priv_data) |
| { |
| if (resource_size(link->resource[PCMCIA_IOPORT_0]) != 0x11) |
| return -ENODEV; |
| return pcmcia_request_io(link); |
| } |
| |
| static int scr24x_probe(struct pcmcia_device *link) |
| { |
| struct scr24x_dev *dev; |
| int ret; |
| |
| dev = kzalloc(sizeof(*dev), GFP_KERNEL); |
| if (!dev) |
| return -ENOMEM; |
| |
| dev->devno = find_first_zero_bit(scr24x_minors, SCR24X_DEVS); |
| if (dev->devno >= SCR24X_DEVS) { |
| ret = -EBUSY; |
| goto err; |
| } |
| |
| mutex_init(&dev->lock); |
| kref_init(&dev->refcnt); |
| |
| link->priv = dev; |
| link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_SET_IO; |
| |
| ret = pcmcia_loop_config(link, scr24x_config_check, NULL); |
| if (ret < 0) |
| goto err; |
| |
| dev->dev = &link->dev; |
| dev->regs = devm_ioport_map(&link->dev, |
| link->resource[PCMCIA_IOPORT_0]->start, |
| resource_size(link->resource[PCMCIA_IOPORT_0])); |
| if (!dev->regs) { |
| ret = -EIO; |
| goto err; |
| } |
| |
| cdev_init(&dev->c_dev, &scr24x_fops); |
| dev->c_dev.owner = THIS_MODULE; |
| ret = cdev_add(&dev->c_dev, MKDEV(MAJOR(scr24x_devt), dev->devno), 1); |
| if (ret < 0) |
| goto err; |
| |
| ret = pcmcia_enable_device(link); |
| if (ret < 0) { |
| pcmcia_disable_device(link); |
| goto err; |
| } |
| |
| device_create(scr24x_class, NULL, MKDEV(MAJOR(scr24x_devt), dev->devno), |
| NULL, "scr24x%d", dev->devno); |
| |
| dev_info(&link->dev, "SCR24x Chip Card Interface\n"); |
| return 0; |
| |
| err: |
| if (dev->devno < SCR24X_DEVS) |
| clear_bit(dev->devno, scr24x_minors); |
| kfree (dev); |
| return ret; |
| } |
| |
| static void scr24x_remove(struct pcmcia_device *link) |
| { |
| struct scr24x_dev *dev = (struct scr24x_dev *)link->priv; |
| |
| device_destroy(scr24x_class, MKDEV(MAJOR(scr24x_devt), dev->devno)); |
| mutex_lock(&dev->lock); |
| pcmcia_disable_device(link); |
| cdev_del(&dev->c_dev); |
| clear_bit(dev->devno, scr24x_minors); |
| dev->dev = NULL; |
| mutex_unlock(&dev->lock); |
| |
| kref_put(&dev->refcnt, scr24x_delete); |
| } |
| |
| static const struct pcmcia_device_id scr24x_ids[] = { |
| PCMCIA_DEVICE_PROD_ID12("HP", "PC Card Smart Card Reader", |
| 0x53cb94f9, 0xbfdf89a5), |
| PCMCIA_DEVICE_PROD_ID1("SCR241 PCMCIA", 0x6271efa3), |
| PCMCIA_DEVICE_PROD_ID1("SCR243 PCMCIA", 0x2054e8de), |
| PCMCIA_DEVICE_PROD_ID1("SCR24x PCMCIA", 0x54a33665), |
| PCMCIA_DEVICE_NULL |
| }; |
| MODULE_DEVICE_TABLE(pcmcia, scr24x_ids); |
| |
| static struct pcmcia_driver scr24x_driver = { |
| .owner = THIS_MODULE, |
| .name = "scr24x_cs", |
| .probe = scr24x_probe, |
| .remove = scr24x_remove, |
| .id_table = scr24x_ids, |
| }; |
| |
| static int __init scr24x_init(void) |
| { |
| int ret; |
| |
| scr24x_class = class_create(THIS_MODULE, "scr24x"); |
| if (IS_ERR(scr24x_class)) |
| return PTR_ERR(scr24x_class); |
| |
| ret = alloc_chrdev_region(&scr24x_devt, 0, SCR24X_DEVS, "scr24x"); |
| if (ret < 0) { |
| class_destroy(scr24x_class); |
| return ret; |
| } |
| |
| ret = pcmcia_register_driver(&scr24x_driver); |
| if (ret < 0) { |
| unregister_chrdev_region(scr24x_devt, SCR24X_DEVS); |
| class_destroy(scr24x_class); |
| } |
| |
| return ret; |
| } |
| |
| static void __exit scr24x_exit(void) |
| { |
| pcmcia_unregister_driver(&scr24x_driver); |
| unregister_chrdev_region(scr24x_devt, SCR24X_DEVS); |
| class_destroy(scr24x_class); |
| } |
| |
| module_init(scr24x_init); |
| module_exit(scr24x_exit); |
| |
| MODULE_AUTHOR("Lubomir Rintel"); |
| MODULE_DESCRIPTION("SCR24x PCMCIA Smart Card Reader Driver"); |
| MODULE_LICENSE("GPL"); |