1 files changed, 726 insertions, 0 deletions

diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
new file mode 100644
index 00000000000..299726f39e2
--- /dev/null
+++ b/drivers/staging/comedi/drivers.c
@@ -0,0 +1,726 @@
+/*
+    module/drivers.c
+    functions for manipulating drivers
+
+    COMEDI - Linux Control and Measurement Device Interface
+    Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
+
+    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 of the License, 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.
+*/
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kconfig.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/fcntl.h>
+#include <linux/ioport.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>	/* for SuSE brokenness */
+#include <linux/vmalloc.h>
+#include <linux/cdev.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/firmware.h>
+
+#include "comedidev.h"
+#include "comedi_internal.h"
+
+struct comedi_driver *comedi_drivers;
+DEFINE_MUTEX(comedi_drivers_list_lock);
+
+int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev)
+{
+	if (hw_dev == dev->hw_dev)
+		return 0;
+	if (dev->hw_dev != NULL)
+		return -EEXIST;
+	dev->hw_dev = get_device(hw_dev);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(comedi_set_hw_dev);
+
+static void comedi_clear_hw_dev(struct comedi_device *dev)
+{
+	put_device(dev->hw_dev);
+	dev->hw_dev = NULL;
+}
+
+/**
+ * comedi_alloc_devpriv() - Allocate memory for the device private data.
+ * @dev: comedi_device struct
+ * @size: size of the memory to allocate
+ */
+void *comedi_alloc_devpriv(struct comedi_device *dev, size_t size)
+{
+	dev->private = kzalloc(size, GFP_KERNEL);
+	return dev->private;
+}
+EXPORT_SYMBOL_GPL(comedi_alloc_devpriv);
+
+int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
+{
+	struct comedi_subdevice *s;
+	int i;
+
+	if (num_subdevices < 1)
+		return -EINVAL;
+
+	s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+	dev->subdevices = s;
+	dev->n_subdevices = num_subdevices;
+
+	for (i = 0; i < num_subdevices; ++i) {
+		s = &dev->subdevices[i];
+		s->device = dev;
+		s->index = i;
+		s->async_dma_dir = DMA_NONE;
+		spin_lock_init(&s->spin_lock);
+		s->minor = -1;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
+
+static void comedi_device_detach_cleanup(struct comedi_device *dev)
+{
+	int i;
+	struct comedi_subdevice *s;
+
+	if (dev->subdevices) {
+		for (i = 0; i < dev->n_subdevices; i++) {
+			s = &dev->subdevices[i];
+			if (s->runflags & SRF_FREE_SPRIV)
+				kfree(s->private);
+			comedi_free_subdevice_minor(s);
+			if (s->async) {
+				comedi_buf_alloc(dev, s, 0);
+				kfree(s->async);
+			}
+		}
+		kfree(dev->subdevices);
+		dev->subdevices = NULL;
+		dev->n_subdevices = 0;
+	}
+	kfree(dev->private);
+	dev->private = NULL;
+	dev->driver = NULL;
+	dev->board_name = NULL;
+	dev->board_ptr = NULL;
+	dev->iobase = 0;
+	dev->iolen = 0;
+	dev->ioenabled = false;
+	dev->irq = 0;
+	dev->read_subdev = NULL;
+	dev->write_subdev = NULL;
+	dev->open = NULL;
+	dev->close = NULL;
+	comedi_clear_hw_dev(dev);
+}
+
+void comedi_device_detach(struct comedi_device *dev)
+{
+	comedi_device_cancel_all(dev);
+	down_write(&dev->attach_lock);
+	dev->attached = false;
+	dev->detach_count++;
+	if (dev->driver)
+		dev->driver->detach(dev);
+	comedi_device_detach_cleanup(dev);
+	up_write(&dev->attach_lock);
+}
+
+static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s)
+{
+	return -EINVAL;
+}
+
+int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s,
+	       struct comedi_insn *insn, unsigned int *data)
+{
+	return -EINVAL;
+}
+
+/**
+ * comedi_timeout() - busy-wait for a driver condition to occur.
+ * @dev: comedi_device struct
+ * @s: comedi_subdevice struct
+ * @insn: comedi_insn struct
+ * @cb: callback to check for the condition
+ * @context: private context from the driver
+ */
+int comedi_timeout(struct comedi_device *dev,
+		   struct comedi_subdevice *s,
+		   struct comedi_insn *insn,
+		   int (*cb)(struct comedi_device *dev,
+			     struct comedi_subdevice *s,
+			     struct comedi_insn *insn,
+			     unsigned long context),
+		   unsigned long context)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(COMEDI_TIMEOUT_MS);
+	int ret;
+
+	while (time_before(jiffies, timeout)) {
+		ret = cb(dev, s, insn, context);
+		if (ret != -EBUSY)
+			return ret;	/* success (0) or non EBUSY errno */
+		cpu_relax();
+	}
+	return -ETIMEDOUT;
+}
+EXPORT_SYMBOL_GPL(comedi_timeout);
+
+/**
+ * comedi_dio_insn_config() - boilerplate (*insn_config) for DIO subdevices.
+ * @dev: comedi_device struct
+ * @s: comedi_subdevice struct
+ * @insn: comedi_insn struct
+ * @data: parameters for the @insn
+ * @mask: io_bits mask for grouped channels
+ */
+int comedi_dio_insn_config(struct comedi_device *dev,
+			   struct comedi_subdevice *s,
+			   struct comedi_insn *insn,
+			   unsigned int *data,
+			   unsigned int mask)
+{
+	unsigned int chan_mask = 1 << CR_CHAN(insn->chanspec);
+
+	if (!mask)
+		mask = chan_mask;
+
+	switch (data[0]) {
+	case INSN_CONFIG_DIO_INPUT:
+		s->io_bits &= ~mask;
+		break;
+
+	case INSN_CONFIG_DIO_OUTPUT:
+		s->io_bits |= mask;
+		break;
+
+	case INSN_CONFIG_DIO_QUERY:
+		data[1] = (s->io_bits & mask) ? COMEDI_OUTPUT : COMEDI_INPUT;
+		return insn->n;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(comedi_dio_insn_config);
+
+/**
+ * comedi_dio_update_state() - update the internal state of DIO subdevices.
+ * @s: comedi_subdevice struct
+ * @data: the channel mask and bits to update
+ */
+unsigned int comedi_dio_update_state(struct comedi_subdevice *s,
+				     unsigned int *data)
+{
+	unsigned int chanmask = (s->n_chan < 32) ? ((1 << s->n_chan) - 1)
+						 : 0xffffffff;
+	unsigned int mask = data[0] & chanmask;
+	unsigned int bits = data[1];
+
+	if (mask) {
+		s->state &= ~mask;
+		s->state |= (bits & mask);
+	}
+
+	return mask;
+}
+EXPORT_SYMBOL_GPL(comedi_dio_update_state);
+
+static int insn_rw_emulate_bits(struct comedi_device *dev,
+				struct comedi_subdevice *s,
+				struct comedi_insn *insn, unsigned int *data)
+{
+	struct comedi_insn new_insn;
+	int ret;
+	static const unsigned channels_per_bitfield = 32;
+
+	unsigned chan = CR_CHAN(insn->chanspec);
+	const unsigned base_bitfield_channel =
+	    (chan < channels_per_bitfield) ? 0 : chan;
+	unsigned int new_data[2];
+
+	memset(new_data, 0, sizeof(new_data));
+	memset(&new_insn, 0, sizeof(new_insn));
+	new_insn.insn = INSN_BITS;
+	new_insn.chanspec = base_bitfield_channel;
+	new_insn.n = 2;
+	new_insn.subdev = insn->subdev;
+
+	if (insn->insn == INSN_WRITE) {
+		if (!(s->subdev_flags & SDF_WRITABLE))
+			return -EINVAL;
+		new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */
+		new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel))
+			      : 0; /* bits */
+	}
+
+	ret = s->insn_bits(dev, s, &new_insn, new_data);
+	if (ret < 0)
+		return ret;
+
+	if (insn->insn == INSN_READ)
+		data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1;
+
+	return 1;
+}
+
+static int __comedi_device_postconfig_async(struct comedi_device *dev,
+					    struct comedi_subdevice *s)
+{
+	struct comedi_async *async;
+	unsigned int buf_size;
+	int ret;
+
+	if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) {
+		dev_warn(dev->class_dev,
+			 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n");
+		return -EINVAL;
+	}
+	if (!s->do_cmdtest) {
+		dev_warn(dev->class_dev,
+			 "async subdevices must have a do_cmdtest() function\n");
+		return -EINVAL;
+	}
+
+	async = kzalloc(sizeof(*async), GFP_KERNEL);
+	if (!async)
+		return -ENOMEM;
+
+	init_waitqueue_head(&async->wait_head);
+	s->async = async;
+
+	async->max_bufsize = comedi_default_buf_maxsize_kb * 1024;
+	buf_size = comedi_default_buf_size_kb * 1024;
+	if (buf_size > async->max_bufsize)
+		buf_size = async->max_bufsize;
+
+	if (comedi_buf_alloc(dev, s, buf_size) < 0) {
+		dev_warn(dev->class_dev, "Buffer allocation failed\n");
+		return -ENOMEM;
+	}
+	if (s->buf_change) {
+		ret = s->buf_change(dev, s, buf_size);
+		if (ret < 0)
+			return ret;
+	}
+
+	comedi_alloc_subdevice_minor(s);
+
+	return 0;
+}
+
+static int __comedi_device_postconfig(struct comedi_device *dev)
+{
+	struct comedi_subdevice *s;
+	int ret;
+	int i;
+
+	for (i = 0; i < dev->n_subdevices; i++) {
+		s = &dev->subdevices[i];
+
+		if (s->type == COMEDI_SUBD_UNUSED)
+			continue;
+
+		if (s->type == COMEDI_SUBD_DO) {
+			if (s->n_chan < 32)
+				s->io_bits = (1 << s->n_chan) - 1;
+			else
+				s->io_bits = 0xffffffff;
+		}
+
+		if (s->len_chanlist == 0)
+			s->len_chanlist = 1;
+
+		if (s->do_cmd) {
+			ret = __comedi_device_postconfig_async(dev, s);
+			if (ret)
+				return ret;
+		}
+
+		if (!s->range_table && !s->range_table_list)
+			s->range_table = &range_unknown;
+
+		if (!s->insn_read && s->insn_bits)
+			s->insn_read = insn_rw_emulate_bits;
+		if (!s->insn_write && s->insn_bits)
+			s->insn_write = insn_rw_emulate_bits;
+
+		if (!s->insn_read)
+			s->insn_read = insn_inval;
+		if (!s->insn_write)
+			s->insn_write = insn_inval;
+		if (!s->insn_bits)
+			s->insn_bits = insn_inval;
+		if (!s->insn_config)
+			s->insn_config = insn_inval;
+
+		if (!s->poll)
+			s->poll = poll_invalid;
+	}
+
+	return 0;
+}
+
+/* do a little post-config cleanup */
+static int comedi_device_postconfig(struct comedi_device *dev)
+{
+	int ret;
+
+	ret = __comedi_device_postconfig(dev);
+	if (ret < 0)
+		return ret;
+	down_write(&dev->attach_lock);
+	dev->attached = true;
+	up_write(&dev->attach_lock);
+	return 0;
+}
+
+/*
+ * Generic recognize function for drivers that register their supported
+ * board names.
+ *
+ * 'driv->board_name' points to a 'const char *' member within the
+ * zeroth element of an array of some private board information
+ * structure, say 'struct foo_board' containing a member 'const char
+ * *board_name' that is initialized to point to a board name string that
+ * is one of the candidates matched against this function's 'name'
+ * parameter.
+ *
+ * 'driv->offset' is the size of the private board information
+ * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is
+ * the length of the array of private board information structures.
+ *
+ * If one of the board names in the array of private board information
+ * structures matches the name supplied to this function, the function
+ * returns a pointer to the pointer to the board name, otherwise it
+ * returns NULL.  The return value ends up in the 'board_ptr' member of
+ * a 'struct comedi_device' that the low-level comedi driver's
+ * 'attach()' hook can convert to a point to a particular element of its
+ * array of private board information structures by subtracting the
+ * offset of the member that points to the board name.  (No subtraction
+ * is required if the board name pointer is the first member of the
+ * private board information structure, which is generally the case.)
+ */
+static void *comedi_recognize(struct comedi_driver *driv, const char *name)
+{
+	char **name_ptr = (char **)driv->board_name;
+	int i;
+
+	for (i = 0; i < driv->num_names; i++) {
+		if (strcmp(*name_ptr, name) == 0)
+			return name_ptr;
+		name_ptr = (void *)name_ptr + driv->offset;
+	}
+
+	return NULL;
+}
+
+static void comedi_report_boards(struct comedi_driver *driv)
+{
+	unsigned int i;
+	const char *const *name_ptr;
+
+	pr_info("comedi: valid board names for %s driver are:\n",
+		driv->driver_name);
+
+	name_ptr = driv->board_name;
+	for (i = 0; i < driv->num_names; i++) {
+		pr_info(" %s\n", *name_ptr);
+		name_ptr = (const char **)((char *)name_ptr + driv->offset);
+	}
+
+	if (driv->num_names == 0)
+		pr_info(" %s\n", driv->driver_name);
+}
+
+/**
+ * comedi_load_firmware() - Request and load firmware for a device.
+ * @dev: comedi_device struct
+ * @hw_device: device struct for the comedi_device
+ * @name: the name of the firmware image
+ * @cb: callback to the upload the firmware image
+ * @context: private context from the driver
+ */
+int comedi_load_firmware(struct comedi_device *dev,
+			 struct device *device,
+			 const char *name,
+			 int (*cb)(struct comedi_device *dev,
+				   const u8 *data, size_t size,
+				   unsigned long context),
+			 unsigned long context)
+{
+	const struct firmware *fw;
+	int ret;
+
+	if (!cb)
+		return -EINVAL;
+
+	ret = request_firmware(&fw, name, device);
+	if (ret == 0) {
+		ret = cb(dev, fw->data, fw->size, context);
+		release_firmware(fw);
+	}
+
+	return ret < 0 ? ret : 0;
+}
+EXPORT_SYMBOL_GPL(comedi_load_firmware);
+
+/**
+ * __comedi_request_region() - Request an I/O reqion for a legacy driver.
+ * @dev: comedi_device struct
+ * @start: base address of the I/O reqion
+ * @len: length of the I/O region
+ */
+int __comedi_request_region(struct comedi_device *dev,
+			    unsigned long start, unsigned long len)
+{
+	if (!start) {
+		dev_warn(dev->class_dev,
+			 "%s: a I/O base address must be specified\n",
+			 dev->board_name);
+		return -EINVAL;
+	}
+
+	if (!request_region(start, len, dev->board_name)) {
+		dev_warn(dev->class_dev, "%s: I/O port conflict (%#lx,%lu)\n",
+			 dev->board_name, start, len);
+		return -EIO;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__comedi_request_region);
+
+/**
+ * comedi_request_region() - Request an I/O reqion for a legacy driver.
+ * @dev: comedi_device struct
+ * @start: base address of the I/O reqion
+ * @len: length of the I/O region
+ */
+int comedi_request_region(struct comedi_device *dev,
+			  unsigned long start, unsigned long len)
+{
+	int ret;
+
+	ret = __comedi_request_region(dev, start, len);
+	if (ret == 0) {
+		dev->iobase = start;
+		dev->iolen = len;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(comedi_request_region);
+
+/**
+ * comedi_legacy_detach() - A generic (*detach) function for legacy drivers.
+ * @dev: comedi_device struct
+ */
+void comedi_legacy_detach(struct comedi_device *dev)
+{
+	if (dev->irq) {
+		free_irq(dev->irq, dev);
+		dev->irq = 0;
+	}
+	if (dev->iobase && dev->iolen) {
+		release_region(dev->iobase, dev->iolen);
+		dev->iobase = 0;
+		dev->iolen = 0;
+	}
+}
+EXPORT_SYMBOL_GPL(comedi_legacy_detach);
+
+int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it)
+{
+	struct comedi_driver *driv;
+	int ret;
+
+	if (dev->attached)
+		return -EBUSY;
+
+	mutex_lock(&comedi_drivers_list_lock);
+	for (driv = comedi_drivers; driv; driv = driv->next) {
+		if (!try_module_get(driv->module))
+			continue;
+		if (driv->num_names) {
+			dev->board_ptr = comedi_recognize(driv, it->board_name);
+			if (dev->board_ptr)
+				break;
+		} else if (strcmp(driv->driver_name, it->board_name) == 0)
+			break;
+		module_put(driv->module);
+	}
+	if (driv == NULL) {
+		/*  recognize has failed if we get here */
+		/*  report valid board names before returning error */
+		for (driv = comedi_drivers; driv; driv = driv->next) {
+			if (!try_module_get(driv->module))
+				continue;
+			comedi_report_boards(driv);
+			module_put(driv->module);
+		}
+		ret = -EIO;
+		goto out;
+	}
+	if (driv->attach == NULL) {
+		/* driver does not support manual configuration */
+		dev_warn(dev->class_dev,
+			 "driver '%s' does not support attach using comedi_config\n",
+			 driv->driver_name);
+		module_put(driv->module);
+		ret = -ENOSYS;
+		goto out;
+	}
+	/* initialize dev->driver here so
+	 * comedi_error() can be called from attach */
+	dev->driver = driv;
+	dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr
+					 : dev->driver->driver_name;
+	ret = driv->attach(dev, it);
+	if (ret >= 0)
+		ret = comedi_device_postconfig(dev);
+	if (ret < 0) {
+		comedi_device_detach(dev);
+		module_put(driv->module);
+	}
+	/* On success, the driver module count has been incremented. */
+out:
+	mutex_unlock(&comedi_drivers_list_lock);
+	return ret;
+}
+
+int comedi_auto_config(struct device *hardware_device,
+		       struct comedi_driver *driver, unsigned long context)
+{
+	struct comedi_device *dev;
+	int ret;
+
+	if (!hardware_device) {
+		pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n");
+		return -EINVAL;
+	}
+	if (!driver) {
+		dev_warn(hardware_device,
+			 "BUG! comedi_auto_config called with NULL comedi driver\n");
+		return -EINVAL;
+	}
+
+	if (!driver->auto_attach) {
+		dev_warn(hardware_device,
+			 "BUG! comedi driver '%s' has no auto_attach handler\n",
+			 driver->driver_name);
+		return -EINVAL;
+	}
+
+	dev = comedi_alloc_board_minor(hardware_device);
+	if (IS_ERR(dev)) {
+		dev_warn(hardware_device,
+			 "driver '%s' could not create device.\n",
+			 driver->driver_name);
+		return PTR_ERR(dev);
+	}
+	/* Note: comedi_alloc_board_minor() locked dev->mutex. */
+
+	dev->driver = driver;
+	dev->board_name = dev->driver->driver_name;
+	ret = driver->auto_attach(dev, context);
+	if (ret >= 0)
+		ret = comedi_device_postconfig(dev);
+	mutex_unlock(&dev->mutex);
+
+	if (ret < 0) {
+		dev_warn(hardware_device,
+			 "driver '%s' failed to auto-configure device.\n",
+			 driver->driver_name);
+		comedi_release_hardware_device(hardware_device);
+	} else {
+		/*
+		 * class_dev should be set properly here
+		 *  after a successful auto config
+		 */
+		dev_info(dev->class_dev,
+			 "driver '%s' has successfully auto-configured '%s'.\n",
+			 driver->driver_name, dev->board_name);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(comedi_auto_config);
+
+void comedi_auto_unconfig(struct device *hardware_device)
+{
+	if (hardware_device == NULL)
+		return;
+	comedi_release_hardware_device(hardware_device);
+}
+EXPORT_SYMBOL_GPL(comedi_auto_unconfig);
+
+int comedi_driver_register(struct comedi_driver *driver)
+{
+	mutex_lock(&comedi_drivers_list_lock);
+	driver->next = comedi_drivers;
+	comedi_drivers = driver;
+	mutex_unlock(&comedi_drivers_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(comedi_driver_register);
+
+void comedi_driver_unregister(struct comedi_driver *driver)
+{
+	struct comedi_driver *prev;
+	int i;
+
+	/* unlink the driver */
+	mutex_lock(&comedi_drivers_list_lock);
+	if (comedi_drivers == driver) {
+		comedi_drivers = driver->next;
+	} else {
+		for (prev = comedi_drivers; prev->next; prev = prev->next) {
+			if (prev->next == driver) {
+				prev->next = driver->next;
+				break;
+			}
+		}
+	}
+	mutex_unlock(&comedi_drivers_list_lock);
+
+	/* check for devices using this driver */
+	for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
+		struct comedi_device *dev = comedi_dev_get_from_minor(i);
+
+		if (!dev)
+			continue;
+
+		mutex_lock(&dev->mutex);
+		if (dev->attached && dev->driver == driver) {
+			if (dev->use_count)
+				dev_warn(dev->class_dev,
+					 "BUG! detaching device with use_count=%d\n",
+					 dev->use_count);
+			comedi_device_detach(dev);
+		}
+		mutex_unlock(&dev->mutex);
+		comedi_dev_put(dev);
+	}
+}
+EXPORT_SYMBOL_GPL(comedi_driver_unregister);