From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- drivers/input/joystick/magellan.c | 205 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 205 insertions(+) create mode 100644 drivers/input/joystick/magellan.c (limited to 'drivers/input/joystick/magellan.c') diff --git a/drivers/input/joystick/magellan.c b/drivers/input/joystick/magellan.c new file mode 100644 index 000000000..201a049c8 --- /dev/null +++ b/drivers/input/joystick/magellan.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 1999-2001 Vojtech Pavlik + */ + +/* + * Magellan and Space Mouse 6dof controller driver for Linux + */ + +#include +#include +#include +#include +#include + +#define DRIVER_DESC "Magellan and SpaceMouse 6dof controller driver" + +MODULE_AUTHOR("Vojtech Pavlik "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/* + * Definitions & global arrays. + */ + +#define MAGELLAN_MAX_LENGTH 32 + +static int magellan_buttons[] = { BTN_0, BTN_1, BTN_2, BTN_3, BTN_4, BTN_5, BTN_6, BTN_7, BTN_8 }; +static int magellan_axes[] = { ABS_X, ABS_Y, ABS_Z, ABS_RX, ABS_RY, ABS_RZ }; + +/* + * Per-Magellan data. + */ + +struct magellan { + struct input_dev *dev; + int idx; + unsigned char data[MAGELLAN_MAX_LENGTH]; + char phys[32]; +}; + +/* + * magellan_crunch_nibbles() verifies that the bytes sent from the Magellan + * have correct upper nibbles for the lower ones, if not, the packet will + * be thrown away. It also strips these upper halves to simplify further + * processing. + */ + +static int magellan_crunch_nibbles(unsigned char *data, int count) +{ + static const unsigned char nibbles[16] __nonstring = "0AB3D56GH9:Kdev; + unsigned char *data = magellan->data; + int i, t; + + if (!magellan->idx) return; + + switch (magellan->data[0]) { + + case 'd': /* Axis data */ + if (magellan->idx != 25) return; + if (magellan_crunch_nibbles(data, 24)) return; + for (i = 0; i < 6; i++) + input_report_abs(dev, magellan_axes[i], + (data[(i << 2) + 1] << 12 | data[(i << 2) + 2] << 8 | + data[(i << 2) + 3] << 4 | data[(i << 2) + 4]) - 32768); + break; + + case 'k': /* Button data */ + if (magellan->idx != 4) return; + if (magellan_crunch_nibbles(data, 3)) return; + t = (data[1] << 1) | (data[2] << 5) | data[3]; + for (i = 0; i < 9; i++) input_report_key(dev, magellan_buttons[i], (t >> i) & 1); + break; + } + + input_sync(dev); +} + +static irqreturn_t magellan_interrupt(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct magellan* magellan = serio_get_drvdata(serio); + + if (data == '\r') { + magellan_process_packet(magellan); + magellan->idx = 0; + } else { + if (magellan->idx < MAGELLAN_MAX_LENGTH) + magellan->data[magellan->idx++] = data; + } + return IRQ_HANDLED; +} + +/* + * magellan_disconnect() is the opposite of magellan_connect() + */ + +static void magellan_disconnect(struct serio *serio) +{ + struct magellan* magellan = serio_get_drvdata(serio); + + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_unregister_device(magellan->dev); + kfree(magellan); +} + +/* + * magellan_connect() is the routine that is called when someone adds a + * new serio device that supports Magellan protocol and registers it as + * an input device. + */ + +static int magellan_connect(struct serio *serio, struct serio_driver *drv) +{ + struct magellan *magellan; + struct input_dev *input_dev; + int err = -ENOMEM; + int i; + + magellan = kzalloc_obj(*magellan); + input_dev = input_allocate_device(); + if (!magellan || !input_dev) + goto fail1; + + magellan->dev = input_dev; + snprintf(magellan->phys, sizeof(magellan->phys), "%s/input0", serio->phys); + + input_dev->name = "LogiCad3D Magellan / SpaceMouse"; + input_dev->phys = magellan->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_MAGELLAN; + input_dev->id.product = 0x0001; + input_dev->id.version = 0x0100; + input_dev->dev.parent = &serio->dev; + + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + + for (i = 0; i < 9; i++) + set_bit(magellan_buttons[i], input_dev->keybit); + + for (i = 0; i < 6; i++) + input_set_abs_params(input_dev, magellan_axes[i], -360, 360, 0, 0); + + serio_set_drvdata(serio, magellan); + + err = serio_open(serio, drv); + if (err) + goto fail2; + + err = input_register_device(magellan->dev); + if (err) + goto fail3; + + return 0; + + fail3: serio_close(serio); + fail2: serio_set_drvdata(serio, NULL); + fail1: input_free_device(input_dev); + kfree(magellan); + return err; +} + +/* + * The serio driver structure. + */ + +static const struct serio_device_id magellan_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_MAGELLAN, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, magellan_serio_ids); + +static struct serio_driver magellan_drv = { + .driver = { + .name = "magellan", + }, + .description = DRIVER_DESC, + .id_table = magellan_serio_ids, + .interrupt = magellan_interrupt, + .connect = magellan_connect, + .disconnect = magellan_disconnect, +}; + +module_serio_driver(magellan_drv); -- cgit v1.3.1