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/maplecontrol.c | 194 ++++++++++++++++++++++++++++++++++ 1 file changed, 194 insertions(+) create mode 100644 drivers/input/joystick/maplecontrol.c (limited to 'drivers/input/joystick/maplecontrol.c') diff --git a/drivers/input/joystick/maplecontrol.c b/drivers/input/joystick/maplecontrol.c new file mode 100644 index 000000000..6293b6e81 --- /dev/null +++ b/drivers/input/joystick/maplecontrol.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SEGA Dreamcast controller driver + * Based on drivers/usb/iforce.c + * + * Copyright Yaegashi Takeshi, 2001 + * Adrian McMenamin, 2008 - 2009 + */ + +#include +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Adrian McMenamin "); +MODULE_DESCRIPTION("SEGA Dreamcast controller driver"); +MODULE_LICENSE("GPL"); + +struct dc_pad { + struct input_dev *dev; + struct maple_device *mdev; +}; + +static void dc_pad_callback(struct mapleq *mq) +{ + unsigned short buttons; + struct maple_device *mapledev = mq->dev; + struct dc_pad *pad = maple_get_drvdata(mapledev); + struct input_dev *dev = pad->dev; + unsigned char *res = mq->recvbuf->buf; + + buttons = ~le16_to_cpup((__le16 *)(res + 8)); + + input_report_abs(dev, ABS_HAT0Y, + (buttons & 0x0010 ? -1 : 0) + (buttons & 0x0020 ? 1 : 0)); + input_report_abs(dev, ABS_HAT0X, + (buttons & 0x0040 ? -1 : 0) + (buttons & 0x0080 ? 1 : 0)); + input_report_abs(dev, ABS_HAT1Y, + (buttons & 0x1000 ? -1 : 0) + (buttons & 0x2000 ? 1 : 0)); + input_report_abs(dev, ABS_HAT1X, + (buttons & 0x4000 ? -1 : 0) + (buttons & 0x8000 ? 1 : 0)); + + input_report_key(dev, BTN_C, buttons & 0x0001); + input_report_key(dev, BTN_B, buttons & 0x0002); + input_report_key(dev, BTN_A, buttons & 0x0004); + input_report_key(dev, BTN_START, buttons & 0x0008); + input_report_key(dev, BTN_Z, buttons & 0x0100); + input_report_key(dev, BTN_Y, buttons & 0x0200); + input_report_key(dev, BTN_X, buttons & 0x0400); + input_report_key(dev, BTN_SELECT, buttons & 0x0800); + + input_report_abs(dev, ABS_GAS, res[10]); + input_report_abs(dev, ABS_BRAKE, res[11]); + input_report_abs(dev, ABS_X, res[12]); + input_report_abs(dev, ABS_Y, res[13]); + input_report_abs(dev, ABS_RX, res[14]); + input_report_abs(dev, ABS_RY, res[15]); +} + +static int dc_pad_open(struct input_dev *dev) +{ + struct dc_pad *pad = dev_get_platdata(&dev->dev); + + maple_getcond_callback(pad->mdev, dc_pad_callback, HZ/20, + MAPLE_FUNC_CONTROLLER); + + return 0; +} + +static void dc_pad_close(struct input_dev *dev) +{ + struct dc_pad *pad = dev_get_platdata(&dev->dev); + + maple_getcond_callback(pad->mdev, dc_pad_callback, 0, + MAPLE_FUNC_CONTROLLER); +} + +/* allow the controller to be used */ +static int probe_maple_controller(struct device *dev) +{ + static const short btn_bit[32] = { + BTN_C, BTN_B, BTN_A, BTN_START, -1, -1, -1, -1, + BTN_Z, BTN_Y, BTN_X, BTN_SELECT, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + }; + + static const short abs_bit[32] = { + -1, -1, -1, -1, ABS_HAT0Y, ABS_HAT0Y, ABS_HAT0X, ABS_HAT0X, + -1, -1, -1, -1, ABS_HAT1Y, ABS_HAT1Y, ABS_HAT1X, ABS_HAT1X, + ABS_GAS, ABS_BRAKE, ABS_X, ABS_Y, ABS_RX, ABS_RY, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + }; + + struct maple_device *mdev = to_maple_dev(dev); + struct maple_driver *mdrv = to_maple_driver(dev->driver); + int i, error; + struct dc_pad *pad; + struct input_dev *idev; + unsigned long data = be32_to_cpu(mdev->devinfo.function_data[0]); + + pad = kzalloc_obj(*pad); + idev = input_allocate_device(); + if (!pad || !idev) { + error = -ENOMEM; + goto fail; + } + + pad->dev = idev; + pad->mdev = mdev; + + maple_set_drvdata(mdev, pad); + + idev->open = dc_pad_open; + idev->close = dc_pad_close; + + for (i = 0; i < 32; i++) { + if (data & (1 << i)) { + if (btn_bit[i] >= 0) + __set_bit(btn_bit[i], idev->keybit); + else if (abs_bit[i] >= 0) + __set_bit(abs_bit[i], idev->absbit); + } + } + + if (idev->keybit[BIT_WORD(BTN_JOYSTICK)]) + idev->evbit[0] |= BIT_MASK(EV_KEY); + + if (idev->absbit[0]) + idev->evbit[0] |= BIT_MASK(EV_ABS); + + for (i = ABS_X; i <= ABS_BRAKE; i++) + input_set_abs_params(idev, i, 0, 255, 0, 0); + + for (i = ABS_HAT0X; i <= ABS_HAT3Y; i++) + input_set_abs_params(idev, i, 1, -1, 0, 0); + + idev->dev.platform_data = pad; + idev->dev.parent = &mdev->dev; + idev->name = mdev->product_name; + idev->id.bustype = BUS_HOST; + + error = input_register_device(idev); + if (error) + goto fail; + + mdev->driver = mdrv; + + return 0; + +fail: + input_free_device(idev); + kfree(pad); + maple_set_drvdata(mdev, NULL); + return error; +} + +static int remove_maple_controller(struct device *dev) +{ + struct maple_device *mdev = to_maple_dev(dev); + struct dc_pad *pad = maple_get_drvdata(mdev); + + mdev->callback = NULL; + input_unregister_device(pad->dev); + maple_set_drvdata(mdev, NULL); + kfree(pad); + + return 0; +} + +static struct maple_driver dc_pad_driver = { + .function = MAPLE_FUNC_CONTROLLER, + .drv = { + .name = "Dreamcast_controller", + .probe = probe_maple_controller, + .remove = remove_maple_controller, + }, +}; + +static int __init dc_pad_init(void) +{ + return maple_driver_register(&dc_pad_driver); +} + +static void __exit dc_pad_exit(void) +{ + maple_driver_unregister(&dc_pad_driver); +} + +module_init(dc_pad_init); +module_exit(dc_pad_exit); -- cgit v1.3.1