commit 42b8ce6f55facfa101462e694d33fc6bca471138 upstream. `do_cmd_ioctl()` in "comedi_fops.c" handles the `COMEDI_CMD` ioctl. This returns `-EAGAIN` if it has copied a modified `struct comedi_cmd` back to user-space. (This occurs when the low-level Comedi driver's `do_cmdtest()` handler returns non-zero to indicate a problem with the contents of the `struct comedi_cmd`, or when the `struct comedi_cmd` has the `CMDF_BOGUS` flag set.) `compat_cmd()` in "comedi_compat32.c" handles the 32-bit compatible version of the `COMEDI_CMD` ioctl. Currently, it never copies a 32-bit compatible version of `struct comedi_cmd` back to user-space, which is at odds with the way the regular `COMEDI_CMD` ioctl is handled. To fix it, change `compat_cmd()` to copy a 32-bit compatible version of the `struct comedi_cmd` back to user-space when the main ioctl handler returns `-EAGAIN`. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zefan Li <lizefan@huawei.com>
commit be8e89087ec2d2c8a1ad1e3db64bf4efdfc3c298 upstream. The hardware range code values and list of valid ranges for the AI subdevice is incorrect for several supported boards. The hardware range code values for all boards except PCI-DAS4020/12 is determined by calling `ai_range_bits_6xxx()` based on the maximum voltage of the range and whether it is bipolar or unipolar, however it only returns the correct hardware range code for the PCI-DAS60xx boards. For PCI-DAS6402/16 (and /12) it returns the wrong code for the unipolar ranges. For PCI-DAS64/Mx/16 it returns the wrong code for all the ranges and the comedi range table is incorrect. Change `ai_range_bits_6xxx()` to use a look-up table pointed to by new member `ai_range_codes` of `struct pcidas64_board` to map the comedi range table indices to the hardware range codes. Use a new comedi range table for the PCI-DAS64/Mx/16 boards (and the commented out variants). Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [Ian: Backported to 3.4] Signed-off-by: Zefan Li <lizefan@huawei.com>
commit 4b18f08be01a7b3c7b6df497137b6e3cb28adaa3 upstream. `do_cmd_ioctl()` is called with the comedi device's mutex locked to process the `COMEDI_CMD` ioctl to set up comedi's asynchronous command handling on a comedi subdevice. `comedi_read()` and `comedi_write()` are the `read` and `write` handlers for the comedi device, but do not lock the mutex (for performance reasons, as some things can hold the mutex for quite a long time). There is a race condition if `comedi_read()` or `comedi_write()` is running at the same time and for the same file object and comedi subdevice as `do_cmd_ioctl()`. `do_cmd_ioctl()` sets the subdevice's `busy` pointer to the file object way before it sets the `SRF_RUNNING` flag in the subdevice's `runflags` member. `comedi_read() and `comedi_write()` check the subdevice's `busy` pointer is pointing to the current file object, then if the `SRF_RUNNING` flag is not set, will call `do_become_nonbusy()` to shut down the asyncronous command. Bad things can happen if the asynchronous command is being shutdown and set up at the same time. To prevent the race, don't set the `busy` pointer until after the `SRF_RUNNING` flag has been set. Also, make sure the mutex is held in `comedi_read()` and `comedi_write()` while calling `do_become_nonbusy()` in order to avoid moving the race condition to a point within that function. Change some error handling `goto cleanup` statements in `do_cmd_ioctl()` to simple `return -ERRFOO` statements as a result of changing when the `busy` pointer is set. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e6391a182865efc896cb2a8d79e07b7ac2f45b48 upstream. The element of `das08_boards[]` for the 'das08jr-16-ao' board has the `ai_encoding` member set to `das08_encode12`. It should be set to `das08_encode16` same as the 'das08jr/16' board. After all, this board has 16-bit AI resolution. The description of the A/D LSB register at offset 0 seems incorrect in the user manual "cio-das08jr-16-ao.pdf" as it implies that the AI resolution is only 12 bits. The diagrams of the A/D LSB and MSB registers show 15 data bits and a sign bit, which matches what the software expects for the `das08_encode16` AI encoding method. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust indentation] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0283f7a100882684ad32b768f9f1ad81658a0b92 upstream. At some point, Measurement Computing / ComputerBoards redesigned the PCI-DIO48H to use a PLX PCI interface chip instead of an AMCC chip. This meant they had to put their hardware registers in the PCI BAR 2 region instead of PCI BAR 1. Unfortunately, they kept the same PCI device ID for the new design. This means the driver recognizes the newer cards, but doesn't work (and is likely to screw up the local configuration registers of the PLX chip) because it's using the wrong region. Since the PCI subvendor and subdevice IDs were both zero on the old design, but are the same as the vendor and device on the new design, we can tell the old design and new design apart easily enough. Split the existing entry for the PCI-DIO48H in `pci_8255_boards[]` into two new entries, referenced by different entries in the PCI device ID table `pci_8255_pci_table[]`. Use the same board name for both entries. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f6b316bcd8c421acd6fa5a6e18b4c846ecb9d965 upstream. Use comedi_dio_update_state() to handle the boilerplate code to update the subdevice s->state. Also, fix a bug where the state of the channels is returned in data[0]. The comedi core expects it to be returned in data[1]. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Reviewed-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2fd2bdfccae61efe18f6b92b6a45fbf936d75b48 upstream. pcmuio_detach() is called by the comedi core even if pcmuio_attach() returned an error, so `dev->private` might be `NULL`. Check for that before dereferencing it. Also, as pointed out by Dan Carpenter, there is no need to check the pointer passed to `kfree()` is non-NULL, so remove that check. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 677a31565692d596ef42ea589b53ba289abf4713 upstream. The `insn_bits` handler `ni_65xx_dio_insn_bits()` has a `for` loop that currently writes (optionally) and reads back up to 5 "ports" consisting of 8 channels each. It reads up to 32 1-bit channels but can only read and write a whole port at once - it needs to handle up to 5 ports as the first channel it reads might not be aligned on a port boundary. It breaks out of the loop early if the next port it handles is beyond the final port on the card. It also breaks out early on the 5th port in the loop if the first channel was aligned. Unfortunately, it doesn't check that the current port it is dealing with belongs to the comedi subdevice the `insn_bits` handler is acting on. That's a bug. Redo the `for` loop to terminate after the final port belonging to the subdevice, changing the loop variable in the process to simplify things a bit. The `for` loop could now try and handle more than 5 ports if the subdevice has more than 40 channels, but the test `if (bitshift >= 32)` ensures it will break out early after 4 or 5 ports (depending on whether the first channel is aligned on a port boundary). (`bitshift` will be between -7 and 7 inclusive on the first iteration, increasing by 8 for each subsequent operation.) Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2c4283ca7cdcc6605859c836fc536fcd83a4525f upstream. In dt282x_ai_insn_read() we call this macro like: wait_for(!mux_busy(), comedi_error(dev, "timeout\n"); return -ETIME;); Because the if statement doesn't have curly braces it means we always return -ETIME and the function never succeeds. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 69acbaac303e8cb948801a9ddd0ac24e86cc4a1b upstream. Comedi devices can do blocking read() or write() (or poll()) if an asynchronous command has been set up, blocking for data (for read()) or buffer space (for write()). Various events associated with the asynchronous command will wake up the blocked reader or writer (or poller). It is also possible to force the asynchronous command to terminate by issuing a `COMEDI_CANCEL` ioctl. That shuts down the asynchronous command, but does not currently wake up the blocked reader or writer (or poller). If the blocked task could be woken up, it would see that the command is no longer active and return. The caller of the `COMEDI_CANCEL` ioctl could attempt to wake up the blocked task by sending a signal, but that's a nasty workaround. Change `do_cancel_ioctl()` to wake up the wait queue after it returns from `do_cancel()`. `do_cancel()` can propagate an error return value from the low-level comedi driver's cancel routine, but it always shuts the command down regardless, so `do_cancel_ioctl()` can wake up he wait queue regardless of the return value from `do_cancel()`. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>