drivers/char/pcmcia/scr24x_cs.c - linux - Git at Google

 // 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;
 	dev->c_dev.ops = &scr24x_fops;
 	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");
	// 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;
	dev->c_dev.ops = &scr24x_fops;
	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");