diff options
| author | Ian Abbott <abbotti@mev.co.uk> | 2026-01-30 19:47:26 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-04-02 16:49:36 +0300 |
| commit | 241cb8dee0f83856c728f4fe2c29e331386c92f2 (patch) | |
| tree | 3ce78c4aea703b632dcd22299ba9bc12ddac4e76 /include | |
| parent | 8f3481028b05e3418b6fe7119428ab44a5b2eb20 (diff) | |
| download | linux-241cb8dee0f83856c728f4fe2c29e331386c92f2.tar.xz | |
comedi: add comedi_check_request_region()
There is an existing comedi_request_region(dev, start, len) function
used by COMEDI drivers for legacy devices to request an I/O port region
starting at a specified base address (which must be non-zero) and with a
specified length. It uses request_region(). On success, it sets
dev->iobase and dev->iolen and returns 0. There is a alternative
function __comedi_request_region(dev, start, len) which does the same
thing without setting dev->iobase and dev->iolen.
Most hardware devices have restrictions on the allowed I/O port base
address and alignment, so add new functions
comedi_check_request_region(dev, start, len, minstart, maxend, minalign)
and __comedi_check_request_region(dev, start, len, minstart, maxend,
minalign) to perform these additional checks. Turn the original
functions into static inline wrapper functions that call the new
functions.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://patch.msgid.link/20260130170416.49994-2-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/comedi/comedidev.h | 53 |
1 files changed, 49 insertions, 4 deletions
diff --git a/include/linux/comedi/comedidev.h b/include/linux/comedi/comedidev.h index 35fdc41845ce..577a08f37aee 100644 --- a/include/linux/comedi/comedidev.h +++ b/include/linux/comedi/comedidev.h @@ -1026,10 +1026,55 @@ int comedi_load_firmware(struct comedi_device *dev, struct device *hw_dev, unsigned long context), unsigned long context); -int __comedi_request_region(struct comedi_device *dev, - unsigned long start, unsigned long len); -int comedi_request_region(struct comedi_device *dev, - unsigned long start, unsigned long len); +int __comedi_check_request_region(struct comedi_device *dev, + unsigned long start, unsigned long len, + unsigned long minstart, unsigned long maxend, + unsigned long minalign); +int comedi_check_request_region(struct comedi_device *dev, + unsigned long start, unsigned long len, + unsigned long minstart, unsigned long maxend, + unsigned long minalign); + +/** + * __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. + */ +static inline int __comedi_request_region(struct comedi_device *dev, + unsigned long start, + unsigned long len) +{ + return __comedi_check_request_region(dev, start, len, 0, ~0ul, 1); +} + +/** + * 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. + */ +static inline int comedi_request_region(struct comedi_device *dev, + unsigned long start, unsigned long len) +{ + return comedi_check_request_region(dev, start, len, 0, ~0ul, 1); +} + void comedi_legacy_detach(struct comedi_device *dev); int comedi_auto_config(struct device *hardware_device, |