diff options
Diffstat (limited to 'drivers/staging/comedi/drivers.c')
| -rw-r--r-- | drivers/staging/comedi/drivers.c | 1184 |
1 files changed, 0 insertions, 1184 deletions
diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c deleted file mode 100644 index 750a6ff3c03c..000000000000 --- a/drivers/staging/comedi/drivers.c +++ /dev/null @@ -1,1184 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* - * 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> - */ - -#include <linux/device.h> -#include <linux/module.h> -#include <linux/errno.h> -#include <linux/kernel.h> -#include <linux/ioport.h> -#include <linux/slab.h> -#include <linux/dma-direction.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); - -/** - * comedi_set_hw_dev() - Set hardware device associated with COMEDI device - * @dev: COMEDI device. - * @hw_dev: Hardware device. - * - * For automatically configured COMEDI devices (resulting from a call to - * comedi_auto_config() or one of its wrappers from the low-level COMEDI - * driver), comedi_set_hw_dev() is called automatically by the COMEDI core - * to associate the COMEDI device with the hardware device. It can also be - * called directly by "legacy" low-level COMEDI drivers that rely on the - * %COMEDI_DEVCONFIG ioctl to configure the hardware as long as the hardware - * has a &struct device. - * - * If @dev->hw_dev is NULL, it gets a reference to @hw_dev and sets - * @dev->hw_dev, otherwise, it does nothing. Calling it multiple times - * with the same hardware device is not considered an error. If it gets - * a reference to the hardware device, it will be automatically 'put' when - * the device is detached from COMEDI. - * - * Returns 0 if @dev->hw_dev was NULL or the same as @hw_dev, otherwise - * returns -EEXIST. - */ -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. - * @size: Size of the memory to allocate. - * - * The allocated memory is zero-filled. @dev->private points to it on - * return. The memory will be automatically freed when the COMEDI device is - * "detached". - * - * Returns a pointer to the allocated memory, or NULL on failure. - */ -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); - -/** - * comedi_alloc_subdevices() - Allocate subdevices for COMEDI device - * @dev: COMEDI device. - * @num_subdevices: Number of subdevices to allocate. - * - * Allocates and initializes an array of &struct comedi_subdevice for the - * COMEDI device. If successful, sets @dev->subdevices to point to the - * first one and @dev->n_subdevices to the number. - * - * Returns 0 on success, -EINVAL if @num_subdevices is < 1, or -ENOMEM if - * failed to allocate the memory. - */ -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. - * - * This is called by low-level COMEDI drivers to allocate an array to record - * the last values written to a subdevice's analog output channels (at least - * by the %INSN_WRITE instruction), to allow them to be read back by an - * %INSN_READ instruction. It also provides a default handler for the - * %INSN_READ instruction unless one has already been set. - * - * On success, @s->readback points to the first element of the array, which - * is zero-filled. The low-level driver is responsible for updating its - * contents. @s->insn_read will be set to comedi_readback_insn_read() - * unless it is already non-NULL. - * - * Returns 0 on success, -EINVAL if the subdevice has no channels, or - * -ENOMEM on allocation failure. - */ -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; - - lockdep_assert_held(&dev->attach_lock); - lockdep_assert_held(&dev->mutex); - if (dev->subdevices) { - for (i = 0; i < dev->n_subdevices; i++) { - s = &dev->subdevices[i]; - if (comedi_can_auto_free_spriv(s)) - 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) -{ - lockdep_assert_held(&dev->mutex); - 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; -} - -static int insn_device_inval(struct comedi_device *dev, - struct comedi_insn *insn, unsigned int *data) -{ - return -EINVAL; -} - -static unsigned int get_zero_valid_routes(struct comedi_device *dev, - unsigned int n_pairs, - unsigned int *pair_data) -{ - return 0; -} - -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. - * @s: COMEDI subdevice. - * @insn: COMEDI instruction. - * @data: Pointer to return the readback data. - * - * Handles the %INSN_READ instruction for subdevices that use the readback - * array allocated by comedi_alloc_subdev_readback(). It may be used - * directly as the subdevice's handler (@s->insn_read) or called via a - * wrapper. - * - * @insn->n is normally 1, which will read a single value. If higher, the - * same element of the readback array will be read multiple times. - * - * Returns @insn->n on success, or -EINVAL if @s->readback is NULL. - */ -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. - * @s: COMEDI subdevice. - * @insn: COMEDI instruction. - * @cb: Callback to check for the condition. - * @context: Private context from the driver. - * - * Busy-waits for up to a second (%COMEDI_TIMEOUT_MS) for the condition or - * some error (other than -EBUSY) to occur. The parameters @dev, @s, @insn, - * and @context are passed to the callback function, which returns -EBUSY to - * continue waiting or some other value to stop waiting (generally 0 if the - * condition occurred, or some error value). - * - * Returns -ETIMEDOUT if timed out, otherwise the return value from the - * callback function. - */ -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. - * @s: COMEDI subdevice. - * @insn: COMEDI instruction. - * @data: Instruction parameters and return data. - * @mask: io_bits mask for grouped channels, or 0 for single channel. - * - * If @mask is 0, it is replaced with a single-bit mask corresponding to the - * channel number specified by @insn->chanspec. Otherwise, @mask - * corresponds to a group of channels (which should include the specified - * channel) that are always configured together as inputs or outputs. - * - * Partially handles the %INSN_CONFIG_DIO_INPUT, %INSN_CONFIG_DIO_OUTPUTS, - * and %INSN_CONFIG_DIO_QUERY instructions. The first two update - * @s->io_bits to record the directions of the masked channels. The last - * one sets @data[1] to the current direction of the group of channels - * (%COMEDI_INPUT) or %COMEDI_OUTPUT) as recorded in @s->io_bits. - * - * The caller is responsible for updating the DIO direction in the hardware - * registers if this function returns 0. - * - * Returns 0 for a %INSN_CONFIG_DIO_INPUT or %INSN_CONFIG_DIO_OUTPUT - * instruction, @insn->n (> 0) for a %INSN_CONFIG_DIO_QUERY instruction, or - * -EINVAL for some other instruction. - */ -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. - * @data: The channel mask and bits to update. - * - * Updates @s->state which holds the internal state of the outputs for DIO - * or DO subdevices (up to 32 channels). @data[0] contains a bit-mask of - * the channels to be updated. @data[1] contains a bit-mask of those - * channels to be set to '1'. The caller is responsible for updating the - * outputs in hardware according to @s->state. As a minimum, the channels - * in the returned bit-mask need to be updated. - * - * Returns @mask with non-existent channels removed. - */ -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_cmd() - Get length of asynchronous command "scan" in - * bytes - * @s: COMEDI subdevice. - * @cmd: COMEDI command. - * - * Determines the overall scan length according to the subdevice type and the - * number of channels in the scan for the specified command. - * - * 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_cmd(struct comedi_subdevice *s, - struct comedi_cmd *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_cmd); - -/** - * comedi_bytes_per_scan() - Get length of asynchronous command "scan" in bytes - * @s: COMEDI subdevice. - * - * Determines the overall scan length according to the subdevice type and the - * number of channels in the scan for the current command. - * - * 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; - - return comedi_bytes_per_scan_cmd(s, cmd); -} -EXPORT_SYMBOL_GPL(comedi_bytes_per_scan); - -static 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 (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; -} - -/** - * comedi_nscans_left() - Return the number of scans left in the command - * @s: COMEDI subdevice. - * @nscans: The expected number of scans or 0 for all available scans. - * - * If @nscans is 0, it is set to the number of scans available in the - * async buffer. - * - * If the async command has a stop_src of %TRIG_COUNT, the @nscans will be - * checked against the number of scans remaining to complete the command. - * - * The return value will then be either the expected number of scans or the - * number of scans remaining to complete the command, whichever is fewer. - */ -unsigned int comedi_nscans_left(struct comedi_subdevice *s, - unsigned int nscans) -{ - if (nscans == 0) { - unsigned int nbytes = comedi_buf_read_n_available(s); - - nscans = nbytes / comedi_bytes_per_scan(s); - } - return __comedi_nscans_left(s, nscans); -} -EXPORT_SYMBOL_GPL(comedi_nscans_left); - -/** - * comedi_nsamples_left() - Return the number of samples left in the command - * @s: COMEDI subdevice. - * @nsamples: The expected number of samples. - * - * Returns the number of samples remaining to complete the command, or the - * specified expected number of samples (@nsamples), whichever is fewer. - */ -unsigned int comedi_nsamples_left(struct comedi_subdevice *s, - unsigned int nsamples) -{ - struct comedi_async *async = s->async; - struct comedi_cmd *cmd = &async->cmd; - unsigned long long scans_left; - unsigned long long samples_left; - - if (cmd->stop_src != TRIG_COUNT) - return nsamples; - - scans_left = __comedi_nscans_left(s, cmd->stop_arg); - if (!scans_left) - return 0; - - samples_left = scans_left * cmd->scan_end_arg - - comedi_bytes_to_samples(s, async->scan_progress); - - if (samples_left < nsamples) - return samples_left; - return nsamples; -} -EXPORT_SYMBOL_GPL(comedi_nsamples_left); - -/** - * comedi_inc_scan_progress() - Update scan progress in asynchronous command - * @s: COMEDI subdevice. - * @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 (%COMEDI_CB_EOS) 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. - * @s: COMEDI subdevice. - * - * Handles outstanding asynchronous acquisition event flags associated - * with the subdevice. Call the subdevice's @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) - 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 _insn; - unsigned int chan = CR_CHAN(insn->chanspec); - unsigned int base_chan = (chan < 32) ? 0 : chan; - unsigned int _data[2]; - int ret; - - memset(_data, 0, sizeof(_data)); - memset(&_insn, 0, sizeof(_insn)); - _insn.insn = INSN_BITS; - _insn.chanspec = base_chan; - _insn.n = 2; - _insn.subdev = insn->subdev; - - if (insn->insn == INSN_WRITE) { - if (!(s->subdev_flags & SDF_WRITABLE)) - return -EINVAL; - _data[0] = 1 << (chan - base_chan); /* mask */ - _data[1] = data[0] ? (1 << (chan - base_chan)) : 0; /* bits */ - } - - ret = s->insn_bits(dev, s, &_insn, _data); - if (ret < 0) - return ret; - - if (insn->insn == INSN_READ) - data[0] = (_data[1] >> (chan - base_chan)) & 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; - - lockdep_assert_held(&dev->mutex); - 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; - } - if (!s->cancel) - dev_warn(dev->class_dev, - "async subdevices should have a cancel() function\n"); - - 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; - - lockdep_assert_held(&dev->mutex); - if (!dev->insn_device_config) - dev->insn_device_config = insn_device_inval; - - if (!dev->get_valid_routes) - dev->get_valid_routes = get_zero_valid_routes; - - 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; - - lockdep_assert_held(&dev->mutex); - 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. - * @device: Hardware device. - * @name: The name of the firmware image. - * @cb: Callback to the upload the firmware image. - * @context: Private context from the driver. - * - * Sends a firmware request for the hardware device and waits for it. Calls - * the callback function to upload the firmware to the device, them releases - * the firmware. - * - * Returns 0 on success, -EINVAL if @cb is NULL, or a negative error number - * from the firmware request or the callback function. - */ -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 region for a legacy driver - * @dev: COMEDI device. - * @start: Base address of the I/O region. - * @len: Length of the I/O region. - * - * Requests the specified I/O port region which must start at a non-zero - * address. - * - * Returns 0 on success, -EINVAL if @start is 0, or -EIO if the request - * fails. - */ -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 region for a legacy driver - * @dev: COMEDI device. - * @start: Base address of the I/O region. - * @len: Length of the I/O region. - * - * Requests the specified I/O port region which must start at a non-zero - * address. - * - * On success, @dev->iobase is set to the base address of the region and - * @dev->iolen is set to its length. - * - * Returns 0 on success, -EINVAL if @start is 0, or -EIO if the request - * fails. - */ -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. - * - * This is a simple, generic 'detach' handler for legacy COMEDI devices that - * just use a single I/O port region and possibly an IRQ and that don't need - * any special clean-up for their private device or subdevice storage. It - * can also be called by a driver-specific 'detach' handler. - * - * If @dev->irq is non-zero, the IRQ will be freed. If @dev->iobase and - * @dev->iolen are both non-zero, the I/O port region will be released. - */ -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; - - lockdep_assert_held(&dev->mutex); - 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 = -EIO; - 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; -} - -/** - * comedi_auto_config() - Create a COMEDI device for a hardware device - * @hardware_device: Hardware device. - * @driver: COMEDI low-level driver for the hardware device. - * @context: Driver context for the auto_attach handler. - * - * Allocates a new COMEDI device for the hardware device and calls the - * low-level driver's 'auto_attach' handler to set-up the hardware and - * allocate the COMEDI subdevices. Additional "post-configuration" setting - * up is performed on successful return from the 'auto_attach' handler. - * If the 'auto_attach' handler fails, the low-level driver's 'detach' - * handler will be called as part of the clean-up. - * - * This is usually called from a wrapper function in a bus-specific COMEDI - * module, which in turn is usually called from a bus device 'probe' - * function in the low-level driver. - * - * Returns 0 on success, -EINVAL if the parameters are invalid or the - * post-configuration determines the driver has set the COMEDI device up - * incorrectly, -ENOMEM if failed to allocate memory, -EBUSY if run out of - * COMEDI minor device numbers, or some negative error number returned by - * the driver's 'auto_attach' handler. - */ -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! %s called with NULL hardware_device\n", __func__); - return -EINVAL; - } - if (!driver) { - dev_warn(hardware_device, - "BUG! %s called with NULL comedi driver\n", __func__); - 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. */ - lockdep_assert_held(&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); - - if (ret < 0) { - dev_warn(hardware_device, - "driver '%s' failed to auto-configure device.\n", - driver->driver_name); - mutex_unlock(&dev->mutex); - 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); - mutex_unlock(&dev->mutex); - } - return ret; -} -EXPORT_SYMBOL_GPL(comedi_auto_config); - -/** - * comedi_auto_unconfig() - Unconfigure auto-allocated COMEDI device - * @hardware_device: Hardware device previously passed to - * comedi_auto_config(). - * - * Cleans up and eventually destroys the COMEDI device allocated by - * comedi_auto_config() for the same hardware device. As part of this - * clean-up, the low-level COMEDI driver's 'detach' handler will be called. - * (The COMEDI device itself will persist in an unattached state if it is - * still open, until it is released, and any mmapped buffers will persist - * until they are munmapped.) - * - * This is usually called from a wrapper module in a bus-specific COMEDI - * module, which in turn is usually set as the bus device 'remove' function - * in the low-level COMEDI driver. - */ -void comedi_auto_unconfig(struct device *hardware_device) -{ - if (!hardware_device) - return; - comedi_release_hardware_device(hardware_device); -} -EXPORT_SYMBOL_GPL(comedi_auto_unconfig); - -/** - * comedi_driver_register() - Register a low-level COMEDI driver - * @driver: Low-level COMEDI driver. - * - * The low-level COMEDI driver is added to the list of registered COMEDI - * drivers. This is used by the handler for the "/proc/comedi" file and is - * also used by the handler for the %COMEDI_DEVCONFIG ioctl to configure - * "legacy" COMEDI devices (for those low-level drivers that support it). - * - * Returns 0. - */ -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); - -/** - * comedi_driver_unregister() - Unregister a low-level COMEDI driver - * @driver: Low-level COMEDI driver. - * - * The low-level COMEDI driver is removed from the list of registered COMEDI - * drivers. Detaches any COMEDI devices attached to the driver, which will - * result in the low-level driver's 'detach' handler being called for those - * devices before this function returns. - */ -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); |