Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1498402 > unrolled thread

[PATCH] char/pcmcia: add scr24x_cs chip card interface driver

Back to article view | Back to linux.kernel

Contents

  [PATCH] char/pcmcia: add scr24x_cs chip card interface driver Lubomir Rintel <lkundrak@v3.sk> - 2016-10-10 18:10 +0200
    Re: [PATCH] char/pcmcia: add scr24x_cs chip card interface driver Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-10-10 19:40 +0200
      Re: [PATCH] char/pcmcia: add scr24x_cs chip card interface driver Arnd Bergmann <arnd@arndb.de> - 2016-10-10 21:30 +0200

#1498402 — [PATCH] char/pcmcia: add scr24x_cs chip card interface driver

This implements only the very basic protocol "Mode A", just to make the
device functional. Patches to implement "Mode C" that uses better bulking
and is interrupt-driver may follow.

The device essentially speaks the same protocol as USB CCID devices do over
the bulk endpoints. The driver exchanges the command submissions and
responses over a plain read()/write() interface, compatible with legacy
OpenCT's pcmcia_block driver.

Patches for the newer CCID driver are available:
https://github.com/lkundrak/CCID/tree/lr/pcmcia_block

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
---
 MAINTAINERS                     |   5 +
 drivers/char/pcmcia/Kconfig     |  11 ++
 drivers/char/pcmcia/Makefile    |   1 +
 drivers/char/pcmcia/scr24x_cs.c | 357 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 374 insertions(+)
 create mode 100644 drivers/char/pcmcia/scr24x_cs.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 5327bbe..8dc6a9f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10608,6 +10608,11 @@ W:	http://www.sunplus.com
 S:	Supported
 F:	arch/score/
 
+SCR24X CHIP CARD INTERFACE DRIVER
+M:	Lubomir Rintel <lkundrak@v3.sk>
+S:	Supported
+F:	drivers/char/pcmcia/scr24x_cs.c
+
 SYSTEM CONTROL & POWER INTERFACE (SCPI) Message Protocol drivers
 M:	Sudeep Holla <sudeep.holla@arm.com>
 L:	linux-arm-kernel@lists.infradead.org
diff --git a/drivers/char/pcmcia/Kconfig b/drivers/char/pcmcia/Kconfig
index 8d3dfb0..1d1e7da 100644
--- a/drivers/char/pcmcia/Kconfig
+++ b/drivers/char/pcmcia/Kconfig
@@ -43,6 +43,17 @@ config CARDMAN_4040
 	  (http://www.omnikey.com/), or a current development version of OpenCT
 	  (http://www.opensc-project.org/opensc).
 
+config SCR24X
+	tristate "SCR24x Chip Card Interface support"
+	depends on PCMCIA
+	help
+	  Enable support for the SCR24x PCMCIA Chip Card Interface.
+
+	  To compile this driver as a module, choose M here.
+	  The module will be called scr24x_cs..
+
+	  If unsure say N.
+
 config IPWIRELESS
 	tristate "IPWireless 3G UMTS PCMCIA card support"
 	depends on PCMCIA && NETDEVICES && TTY
diff --git a/drivers/char/pcmcia/Makefile b/drivers/char/pcmcia/Makefile
index 0aae209..5b836bc 100644
--- a/drivers/char/pcmcia/Makefile
+++ b/drivers/char/pcmcia/Makefile
@@ -7,3 +7,4 @@
 obj-$(CONFIG_SYNCLINK_CS) += synclink_cs.o
 obj-$(CONFIG_CARDMAN_4000) += cm4000_cs.o
 obj-$(CONFIG_CARDMAN_4040) += cm4040_cs.o
+obj-$(CONFIG_SCR24X) += scr24x_cs.o
diff --git a/drivers/char/pcmcia/scr24x_cs.c b/drivers/char/pcmcia/scr24x_cs.c
new file mode 100644
index 0000000..24379ac
--- /dev/null
+++ b/drivers/char/pcmcia/scr24x_cs.c
@@ -0,0 +1,357 @@
+/*
+ * 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.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/cdev.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;
+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 nonseekable_open(inode, filp);
+}
+
+static int scr24x_release(struct inode *inode, struct file *filp)
+{
+	struct scr24x_dev *dev = filp->private_data;
+
+	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;
+	}
+	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);
+
+	dev->devno = find_first_zero_bit(scr24x_minors, SCR24X_DEVS);
+	if (dev->devno >= SCR24X_DEVS)
+		return -EBUSY;
+
+	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:
+	clear_bit(dev->devno, scr24x_minors);
+	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");
-- 
2.7.4

[toc] | [next] | [standalone]

#1498451

On Mon, Oct 10, 2016 at 05:58:15PM +0200, Lubomir Rintel wrote:
> This implements only the very basic protocol "Mode A", just to make the
> device functional. Patches to implement "Mode C" that uses better bulking
> and is interrupt-driver may follow.
> 
> The device essentially speaks the same protocol as USB CCID devices do over
> the bulk endpoints. The driver exchanges the command submissions and
> responses over a plain read()/write() interface, compatible with legacy
> OpenCT's pcmcia_block driver.
> 
> Patches for the newer CCID driver are available:
> https://github.com/lkundrak/CCID/tree/lr/pcmcia_block
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> ---
>  MAINTAINERS                     |   5 +
>  drivers/char/pcmcia/Kconfig     |  11 ++
>  drivers/char/pcmcia/Makefile    |   1 +
>  drivers/char/pcmcia/scr24x_cs.c | 357 ++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 374 insertions(+)
>  create mode 100644 drivers/char/pcmcia/scr24x_cs.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 5327bbe..8dc6a9f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -10608,6 +10608,11 @@ W:	http://www.sunplus.com
>  S:	Supported
>  F:	arch/score/
>  
> +SCR24X CHIP CARD INTERFACE DRIVER
> +M:	Lubomir Rintel <lkundrak@v3.sk>
> +S:	Supported
> +F:	drivers/char/pcmcia/scr24x_cs.c
> +
>  SYSTEM CONTROL & POWER INTERFACE (SCPI) Message Protocol drivers
>  M:	Sudeep Holla <sudeep.holla@arm.com>
>  L:	linux-arm-kernel@lists.infradead.org
> diff --git a/drivers/char/pcmcia/Kconfig b/drivers/char/pcmcia/Kconfig
> index 8d3dfb0..1d1e7da 100644
> --- a/drivers/char/pcmcia/Kconfig
> +++ b/drivers/char/pcmcia/Kconfig
> @@ -43,6 +43,17 @@ config CARDMAN_4040
>  	  (http://www.omnikey.com/), or a current development version of OpenCT
>  	  (http://www.opensc-project.org/opensc).
>  
> +config SCR24X
> +	tristate "SCR24x Chip Card Interface support"
> +	depends on PCMCIA
> +	help
> +	  Enable support for the SCR24x PCMCIA Chip Card Interface.
> +
> +	  To compile this driver as a module, choose M here.
> +	  The module will be called scr24x_cs..
> +
> +	  If unsure say N.

A new PCMCIA driver?  What decade is this?  :)

> +
>  config IPWIRELESS
>  	tristate "IPWireless 3G UMTS PCMCIA card support"
>  	depends on PCMCIA && NETDEVICES && TTY
> diff --git a/drivers/char/pcmcia/Makefile b/drivers/char/pcmcia/Makefile
> index 0aae209..5b836bc 100644
> --- a/drivers/char/pcmcia/Makefile
> +++ b/drivers/char/pcmcia/Makefile
> @@ -7,3 +7,4 @@
>  obj-$(CONFIG_SYNCLINK_CS) += synclink_cs.o
>  obj-$(CONFIG_CARDMAN_4000) += cm4000_cs.o
>  obj-$(CONFIG_CARDMAN_4040) += cm4040_cs.o
> +obj-$(CONFIG_SCR24X) += scr24x_cs.o
> diff --git a/drivers/char/pcmcia/scr24x_cs.c b/drivers/char/pcmcia/scr24x_cs.c
> new file mode 100644
> index 0000000..24379ac
> --- /dev/null
> +++ b/drivers/char/pcmcia/scr24x_cs.c
> @@ -0,0 +1,357 @@
> +/*
> + * 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.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2, or (at your option)
> + * any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; see the file COPYING.  If not, write to
> + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/delay.h>
> +#include <linux/cdev.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;
> +dev_t scr24x_devt;

global variable?  And why do you need a char device for this type of
hardware?  Isn't there already an existing interface for this device
class?


> +
> +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 nonseekable_open(inode, filp);
> +}
> +
> +static int scr24x_release(struct inode *inode, struct file *filp)
> +{
> +	struct scr24x_dev *dev = filp->private_data;
> +
> +	kref_put(&dev->refcnt, scr24x_delete);

No locking?

thanks,

greg k-h

[toc] | [prev] | [next] | [standalone]

#1498491

On Monday, October 10, 2016 7:33:45 PM CEST Greg Kroah-Hartman wrote:
> > +
> > +#define SCR24X_DEVS 8
> > +static DECLARE_BITMAP(scr24x_minors, SCR24X_DEVS);
> > +
> > +static struct class *scr24x_class;
> > +dev_t scr24x_devt;
> 
> global variable?  And why do you need a char device for this type of
> hardware?  Isn't there already an existing interface for this device
> class?

It looks like this is modeled after the other two chip card drivers
in drivers/char/pcmcia/, which are also char devices. Looking at
https://pcsclite.alioth.debian.org/ccid.html, it seems that other
drivers for this protocol are typically in user space when they are
for USB devices, so apparently no existing subsystem abstraction
in the kernel.

This reminds me that there is just one other driver in drivers/char/pcmcia
(synclink_cs), and that should be moved to drivers/tty/ with the other
synclink variants. If we do this, we could rename drivers/char/pcmcia
to something that implies "smartcard".

	Arnd

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web