On 11/2/24 10:46, Ahmad Khalifa wrote:
Add a userspace-configured driver that can receive IOCTRL commands to monitor devices over IO or ACPI access. - registers a miscdevice at /dev/trim-control - awaits attach/detach ioctrl commands with device details - reads sensor values from: 1. IO select registers, 2. IO direct registers or 3. ACPI method calls (single arg) - applies basic conversions: multiply, divide, dividend divisor Useful when there is prior knowledge of the device or when experimenting with newer devices using old device info. Another use is for debugging other drivers when raw reg values need to be compared with what the full driver prints out. Drawbacks: Not aware of any device. It's readonly. Readonly does not make it safe as it still writes for address select and bank select. Needs an ioctrl and cannot be modloaded through config or modalias
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diff --git a/trivialmon.c b/trivialmon.c new file mode 100644 index 0000000..11e5829 --- /dev/null +++ b/trivialmon.c @@ -0,0 +1,844 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * trivialmon - Trivial Hardware Monitor Driver (Trim) + * + * Userspace-configured monitor controlled through IOCTL + * + * DISCLAIMER: Don't run this with other hwmon modules for the same device. + * You could easily FRY your motherboard! You could also easily FRY YOUR CPU! + *
This is way too risky to add to the kernel. I think it is much better kept out-of-tree, with lots of disclaimers and users (hopefully) understanding what they get into when loading this module. I had thought about something similar some time ago, though limited to i2c devices and using some kind of command language, not open ended ioctls. I gave up on it for the same reason: For some i2c devices, just reading from a register may be understood as command, such as "restore factory configuration". If such a command is executed on the wrong chip, such as a power controller or a display controller, it can easily make the hardware unusable. It is bad enough that this can happen with a kernel driver as well, or with someone executing i2c commands from userspace directly. I really don't want to make that even easier. Guenter
