--- /dev/null
+/*
+ module/drivers.c
+ functions for manipulating drivers
+
+ COMEDI - Linux Control and Measurement Device Interface
+ Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
+ Copyright (C) 2002 Frank Mori Hess <fmhess@users.sourceforge.net>
+
+ 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;
+/* protects access to 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)
+ 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);
+
+/**
+ * comedi_alloc_subdev_readback() - Allocate memory for the subdevice readback.
+ * @s: comedi_subdevice struct
+ */
+int comedi_alloc_subdev_readback(struct comedi_subdevice *s)
+{
+ if (!s->n_chan)
+ return -EINVAL;
+
+ s->readback = kcalloc(s->n_chan, sizeof(*s->readback), GFP_KERNEL);
+ if (!s->readback)
+ return -ENOMEM;
+
+ if (!s->insn_read)
+ s->insn_read = comedi_readback_insn_read;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(comedi_alloc_subdev_readback);
+
+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 & COMEDI_SRF_FREE_SPRIV)
+ kfree(s->private);
+ comedi_free_subdevice_minor(s);
+ if (s->async) {
+ comedi_buf_alloc(dev, s, 0);
+ kfree(s->async);
+ }
+ kfree(s->readback);
+ }
+ kfree(dev->subdevices);
+ dev->subdevices = NULL;
+ dev->n_subdevices = 0;
+ }
+ kfree(dev->private);
+ kfree(dev->pacer);
+ dev->private = NULL;
+ dev->pacer = NULL;
+ dev->driver = NULL;
+ dev->board_name = NULL;
+ dev->board_ptr = NULL;
+ dev->mmio = 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_readback_insn_read() - A generic (*insn_read) for subdevice readback.
+ * @dev: comedi_device struct
+ * @s: comedi_subdevice struct
+ * @insn: comedi_insn struct
+ * @data: pointer to return the readback data
+ */
+int comedi_readback_insn_read(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned int *data)
+{
+ unsigned int chan = CR_CHAN(insn->chanspec);
+ int i;
+
+ if (!s->readback)
+ return -EINVAL;
+
+ for (i = 0; i < insn->n; i++)
+ data[i] = s->readback[chan];
+
+ return insn->n;
+}
+EXPORT_SYMBOL_GPL(comedi_readback_insn_read);
+
+/**
+ * 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);
+
+/**
+ * comedi_bytes_per_scan - get length of asynchronous command "scan" in bytes
+ * @s: comedi_subdevice struct
+ *
+ * Determines the overall scan length according to the subdevice type and the
+ * number of channels in the scan.
+ *
+ * For digital input, output or input/output subdevices, samples for multiple
+ * channels are assumed to be packed into one or more unsigned short or
+ * unsigned int values according to the subdevice's SDF_LSAMPL flag. For other
+ * types of subdevice, samples are assumed to occupy a whole unsigned short or
+ * unsigned int according to the SDF_LSAMPL flag.
+ *
+ * Returns the overall scan length in bytes.
+ */
+unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s)
+{
+ struct comedi_cmd *cmd = &s->async->cmd;
+ unsigned int num_samples;
+ unsigned int bits_per_sample;
+
+ switch (s->type) {
+ case COMEDI_SUBD_DI:
+ case COMEDI_SUBD_DO:
+ case COMEDI_SUBD_DIO:
+ bits_per_sample = 8 * comedi_bytes_per_sample(s);
+ num_samples = DIV_ROUND_UP(cmd->scan_end_arg, bits_per_sample);
+ break;
+ default:
+ num_samples = cmd->scan_end_arg;
+ break;
+ }
+ return comedi_samples_to_bytes(s, num_samples);
+}
+EXPORT_SYMBOL_GPL(comedi_bytes_per_scan);
+
+/**
+ * comedi_nscans_left - return the number of scans left in the command
+ * @s: comedi_subdevice struct
+ * @nscans: the expected number of scans
+ *
+ * If nscans is 0, the number of scans available in the async buffer will be
+ * used. Otherwise the expected number of scans will be used.
+ *
+ * If the async command has a stop_src of TRIG_COUNT, the nscans will be
+ * checked against the number of scans left in the command.
+ *
+ * The return value will then be either the expected number of scans or the
+ * number of scans remaining in the command.
+ */
+unsigned int comedi_nscans_left(struct comedi_subdevice *s,
+ unsigned int nscans)
+{
+ struct comedi_async *async = s->async;
+ struct comedi_cmd *cmd = &async->cmd;
+
+ if (nscans == 0) {
+ unsigned int nbytes = comedi_buf_read_n_available(s);
+
+ nscans = nbytes / comedi_bytes_per_scan(s);
+ }
+
+ if (cmd->stop_src == TRIG_COUNT) {
+ unsigned int scans_left = 0;
+
+ if (async->scans_done < cmd->stop_arg)
+ scans_left = cmd->stop_arg - async->scans_done;
+
+ if (nscans > scans_left)
+ nscans = scans_left;
+ }
+ return nscans;
+}
+EXPORT_SYMBOL_GPL(comedi_nscans_left);
+
+/**
+ * comedi_nsamples_left - return the number of samples left in the command
+ * @s: comedi_subdevice struct
+ * @nsamples: the expected number of samples
+ *
+ * Returns the expected number of samples of the number of samples remaining
+ * in the command.
+ */
+unsigned int comedi_nsamples_left(struct comedi_subdevice *s,
+ unsigned int nsamples)
+{
+ struct comedi_async *async = s->async;
+ struct comedi_cmd *cmd = &async->cmd;
+
+ if (cmd->stop_src == TRIG_COUNT) {
+ /* +1 to force comedi_nscans_left() to return the scans left */
+ unsigned int nscans = (nsamples / cmd->scan_end_arg) + 1;
+ unsigned int scans_left = comedi_nscans_left(s, nscans);
+ unsigned int scan_pos =
+ comedi_bytes_to_samples(s, async->scan_progress);
+ unsigned long long samples_left = 0;
+
+ if (scans_left) {
+ samples_left = ((unsigned long long)scans_left *
+ cmd->scan_end_arg) - scan_pos;
+ }
+
+ if (samples_left < nsamples)
+ nsamples = samples_left;
+ }
+ return nsamples;
+}
+EXPORT_SYMBOL_GPL(comedi_nsamples_left);
+
+/**
+ * comedi_inc_scan_progress - update scan progress in asynchronous command
+ * @s: comedi_subdevice struct
+ * @num_bytes: amount of data in bytes to increment scan progress
+ *
+ * Increments the scan progress by the number of bytes specified by num_bytes.
+ * If the scan progress reaches or exceeds the scan length in bytes, reduce
+ * it modulo the scan length in bytes and set the "end of scan" asynchronous
+ * event flag to be processed later.
+ */
+void comedi_inc_scan_progress(struct comedi_subdevice *s,
+ unsigned int num_bytes)
+{
+ struct comedi_async *async = s->async;
+ struct comedi_cmd *cmd = &async->cmd;
+ unsigned int scan_length = comedi_bytes_per_scan(s);
+
+ /* track the 'cur_chan' for non-SDF_PACKED subdevices */
+ if (!(s->subdev_flags & SDF_PACKED)) {
+ async->cur_chan += comedi_bytes_to_samples(s, num_bytes);
+ async->cur_chan %= cmd->chanlist_len;
+ }
+
+ async->scan_progress += num_bytes;
+ if (async->scan_progress >= scan_length) {
+ unsigned int nscans = async->scan_progress / scan_length;
+
+ if (async->scans_done < (UINT_MAX - nscans))
+ async->scans_done += nscans;
+ else
+ async->scans_done = UINT_MAX;
+
+ async->scan_progress %= scan_length;
+ async->events |= COMEDI_CB_EOS;
+ }
+}
+EXPORT_SYMBOL_GPL(comedi_inc_scan_progress);
+
+/**
+ * comedi_handle_events - handle events and possibly stop acquisition
+ * @dev: comedi_device struct
+ * @s: comedi_subdevice struct
+ *
+ * Handles outstanding asynchronous acquisition event flags associated
+ * with the subdevice. Call the subdevice's "->cancel()" handler if the
+ * "end of acquisition", "error" or "overflow" event flags are set in order
+ * to stop the acquisition at the driver level.
+ *
+ * Calls comedi_event() to further process the event flags, which may mark
+ * the asynchronous command as no longer running, possibly terminated with
+ * an error, and may wake up tasks.
+ *
+ * Return a bit-mask of the handled events.
+ */
+unsigned int comedi_handle_events(struct comedi_device *dev,
+ struct comedi_subdevice *s)
+{
+ unsigned int events = s->async->events;
+
+ if (events == 0)
+ return events;
+
+ if (events & COMEDI_CB_CANCEL_MASK)
+ s->cancel(dev, s);
+
+ comedi_event(dev, s);
+
+ return events;
+}
+EXPORT_SYMBOL_GPL(comedi_handle_events);
+
+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);
+ 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) {
+ /* 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) {
+ /* 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;
+ }
+ 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)
+ 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);
Code Review / kvmfornfv.git / blobdiff