| Message ID | FCAC702C-F84A-47F9-8C78-BBBB34D08500@live.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Touch Bar DRM driver for x86 Macs | expand |
Hi Am 26.02.25 um 17:04 schrieb Aditya Garg: > From: Kerem Karabay <kekrby@gmail.com> > > The Touch Bars found on x86 Macs support two USB configurations: one > where the device presents itself as a HID keyboard and can display > predefined sets of keys, and one where the operating system has full > control over what is displayed. > > This commit adds support for the display functionality of the second > configuration. Functionality for the first configuration has been > merged in the HID tree. > > Note that this driver has only been tested on T2 Macs, and only includes > the USB device ID for these devices. Testing on T1 Macs would be > appreciated. > > Credit goes to Ben (Bingxing) Wang on GitHub for reverse engineering > most of the protocol. > > Also, as requested by Andy, I would like to clarify the use of __packed > structs in this driver: > > - All the packed structs are aligned except for appletbdrm_msg_information. > - We have to pack appletbdrm_msg_information since it is requirement of > the protocol. > - We compared binaries compiled by keeping the rest structs __packed and > not __packed using bloat-o-meter, and __packed was not affecting code > generation. > - To maintain consistency, rest structs have been kept __packed. > > I would also like to point out that since the driver was reverse-engineered > the actual data types of the protocol might be different, including, but > not limited to, endianness. > > Link: https://github.com/imbushuo/DFRDisplayKm > Signed-off-by: Kerem Karabay <kekrby@gmail.com> > Co-developed-by: Atharva Tiwari <evepolonium@gmail.com> > Signed-off-by: Atharva Tiwari <evepolonium@gmail.com> > Co-developed-by: Aditya Garg <gargaditya08@live.com> > Signed-off-by: Aditya Garg <gargaditya08@live.com> > Signed-off-by: Aun-Ali Zaidi <admin@kodeit.net> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Thanks for the effort. As far as I'm concerned, this driver looks good. If no further comments come in, I can add it to the DRM tree in a few days. Best regards Thomas > --- > v2 -> > - Add the driver to MAINTAINERS. > - Allocate memory for request and response in plane's atomic-check helper > - Void the use of drm_fb_blit() > - Implement atomic_disable > - Make PRIME work > - Remove the date field from struct drm_driver > - intersect damage with dst_clip > - Register DRM device in appletbdrm_probe > - Clear the display as the final call in probe > - Select hid_multitouch as well in kconfig > > v3 -> > - Change commit message to credit Ben (Bingxing) Wang > > v4 -> > - Use "Link:" in commit message > - Specify why __packed has been used in commit message > - Use %p4cc instead of %p4ch for errors > - Add myself to Maintainers > - Remove #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > - Add missing header files > - Use return 0; instead of return ret; in static int appletbdrm_send_request > - Better errno types used in appletbdrm_read_response > - Use BITS_TO_BYTES() to convert APPLETBDRM_BITS_PER_PIXEL to bytes > - Remove redundant else in plane_helper_atomic_check > - Remove unnecessary use of 0xff in request->msg_id = timestamp & 0xff; > - Remove duplicated struct device in struct appletbdrm_device > - clear frames_size and request_size as well in primary_plane_helper_atomic_update > - Allocate using kzalloc instead of kmemdup > - Use drm_err() instead of dev_err_probe() > - Avoid clearing drm->mode_config.min_width and height to 0 > - Use put_device() to release the DMA device in appletbdrm_disconnect > > v5 -> > - Convert leftover dev_err_probe to drm_err > - Add missing period in comment > - Use struct device *dmadev instead of struct device *dev in struct appletbdrm_device > - Instead of using __APPLETBDRM_MSG_STR4(str4) macro, the hex values have been directly used > - Remove modules that were not needed from kconfig > > v6 -> > - Clear the drm pointer to NULL in probe > - Add back else if in atomic_check for the sake of consistency with other drm drivers > > v7 -> > - Remove unused variable old_appletbdrm_state > - Remove unused header linux/dev_printk.h > - Add drm/drm_print.h since we are using drm_err > > MAINTAINERS | 8 + > drivers/gpu/drm/tiny/Kconfig | 12 + > drivers/gpu/drm/tiny/Makefile | 1 + > drivers/gpu/drm/tiny/appletbdrm.c | 841 ++++++++++++++++++++++++++++++ > 4 files changed, 862 insertions(+) > create mode 100644 drivers/gpu/drm/tiny/appletbdrm.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index efee40ea5..f7c97eb24 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -7148,6 +7148,14 @@ S: Supported > T: git https://gitlab.freedesktop.org/drm/misc/kernel.git > F: drivers/gpu/drm/sun4i/sun8i* > > +DRM DRIVER FOR APPLE TOUCH BARS > +M: Aun-Ali Zaidi <admin@kodeit.net> > +M: Aditya Garg <gargaditya08@live.com> > +L: dri-devel@lists.freedesktop.org > +S: Maintained > +T: git https://gitlab.freedesktop.org/drm/misc/kernel.git > +F: drivers/gpu/drm/tiny/appletbdrm.c > + > DRM DRIVER FOR ARM PL111 CLCD > M: Linus Walleij <linus.walleij@linaro.org> > S: Maintained > diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig > index 94cbdb133..54c84c980 100644 > --- a/drivers/gpu/drm/tiny/Kconfig > +++ b/drivers/gpu/drm/tiny/Kconfig > @@ -1,5 +1,17 @@ > # SPDX-License-Identifier: GPL-2.0-only > > +config DRM_APPLETBDRM > + tristate "DRM support for Apple Touch Bars" > + depends on DRM && USB && MMU > + select DRM_GEM_SHMEM_HELPER > + select DRM_KMS_HELPER > + help > + Say Y here if you want support for the display of Touch Bars on x86 > + MacBook Pros. > + > + To compile this driver as a module, choose M here: the > + module will be called appletbdrm. > + > config DRM_ARCPGU > tristate "ARC PGU" > depends on DRM && OF > diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile > index 60816d2eb..0a3a7837a 100644 > --- a/drivers/gpu/drm/tiny/Makefile > +++ b/drivers/gpu/drm/tiny/Makefile > @@ -1,5 +1,6 @@ > # SPDX-License-Identifier: GPL-2.0-only > > +obj-$(CONFIG_DRM_APPLETBDRM) += appletbdrm.o > obj-$(CONFIG_DRM_ARCPGU) += arcpgu.o > obj-$(CONFIG_DRM_BOCHS) += bochs.o > obj-$(CONFIG_DRM_CIRRUS_QEMU) += cirrus-qemu.o > diff --git a/drivers/gpu/drm/tiny/appletbdrm.c b/drivers/gpu/drm/tiny/appletbdrm.c > new file mode 100644 > index 000000000..f5d177e23 > --- /dev/null > +++ b/drivers/gpu/drm/tiny/appletbdrm.c > @@ -0,0 +1,841 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Apple Touch Bar DRM Driver > + * > + * Copyright (c) 2023 Kerem Karabay <kekrby@gmail.com> > + */ > + > +#include <linux/align.h> > +#include <linux/array_size.h> > +#include <linux/bitops.h> > +#include <linux/bug.h> > +#include <linux/container_of.h> > +#include <linux/err.h> > +#include <linux/module.h> > +#include <linux/overflow.h> > +#include <linux/slab.h> > +#include <linux/types.h> > +#include <linux/unaligned.h> > +#include <linux/usb.h> > + > +#include <drm/drm_atomic.h> > +#include <drm/drm_atomic_helper.h> > +#include <drm/drm_crtc.h> > +#include <drm/drm_damage_helper.h> > +#include <drm/drm_drv.h> > +#include <drm/drm_encoder.h> > +#include <drm/drm_format_helper.h> > +#include <drm/drm_fourcc.h> > +#include <drm/drm_framebuffer.h> > +#include <drm/drm_gem_atomic_helper.h> > +#include <drm/drm_gem_framebuffer_helper.h> > +#include <drm/drm_gem_shmem_helper.h> > +#include <drm/drm_plane.h> > +#include <drm/drm_print.h> > +#include <drm/drm_probe_helper.h> > + > +#define APPLETBDRM_PIXEL_FORMAT cpu_to_le32(0x52474241) /* RGBA, the actual format is BGR888 */ > +#define APPLETBDRM_BITS_PER_PIXEL 24 > + > +#define APPLETBDRM_MSG_CLEAR_DISPLAY cpu_to_le32(0x434c5244) /* CLRD */ > +#define APPLETBDRM_MSG_GET_INFORMATION cpu_to_le32(0x47494e46) /* GINF */ > +#define APPLETBDRM_MSG_UPDATE_COMPLETE cpu_to_le32(0x5544434c) /* UDCL */ > +#define APPLETBDRM_MSG_SIGNAL_READINESS cpu_to_le32(0x52454459) /* REDY */ > + > +#define APPLETBDRM_BULK_MSG_TIMEOUT 1000 > + > +#define drm_to_adev(_drm) container_of(_drm, struct appletbdrm_device, drm) > +#define adev_to_udev(adev) interface_to_usbdev(to_usb_interface(adev->dmadev)) > + > +struct appletbdrm_msg_request_header { > + __le16 unk_00; > + __le16 unk_02; > + __le32 unk_04; > + __le32 unk_08; > + __le32 size; > +} __packed; > + > +struct appletbdrm_msg_response_header { > + u8 unk_00[16]; > + __le32 msg; > +} __packed; > + > +struct appletbdrm_msg_simple_request { > + struct appletbdrm_msg_request_header header; > + __le32 msg; > + u8 unk_14[8]; > + __le32 size; > +} __packed; > + > +struct appletbdrm_msg_information { > + struct appletbdrm_msg_response_header header; > + u8 unk_14[12]; > + __le32 width; > + __le32 height; > + u8 bits_per_pixel; > + __le32 bytes_per_row; > + __le32 orientation; > + __le32 bitmap_info; > + __le32 pixel_format; > + __le32 width_inches; /* floating point */ > + __le32 height_inches; /* floating point */ > +} __packed; > + > +struct appletbdrm_frame { > + __le16 begin_x; > + __le16 begin_y; > + __le16 width; > + __le16 height; > + __le32 buf_size; > + u8 buf[]; > +} __packed; > + > +struct appletbdrm_fb_request_footer { > + u8 unk_00[12]; > + __le32 unk_0c; > + u8 unk_10[12]; > + __le32 unk_1c; > + __le64 timestamp; > + u8 unk_28[12]; > + __le32 unk_34; > + u8 unk_38[20]; > + __le32 unk_4c; > +} __packed; > + > +struct appletbdrm_fb_request { > + struct appletbdrm_msg_request_header header; > + __le16 unk_10; > + u8 msg_id; > + u8 unk_13[29]; > + /* > + * Contents of `data`: > + * - struct appletbdrm_frame frames[]; > + * - struct appletbdrm_fb_request_footer footer; > + * - padding to make the total size a multiple of 16 > + */ > + u8 data[]; > +} __packed; > + > +struct appletbdrm_fb_request_response { > + struct appletbdrm_msg_response_header header; > + u8 unk_14[12]; > + __le64 timestamp; > +} __packed; > + > +struct appletbdrm_device { > + struct device *dmadev; > + > + unsigned int in_ep; > + unsigned int out_ep; > + > + unsigned int width; > + unsigned int height; > + > + struct drm_device drm; > + struct drm_display_mode mode; > + struct drm_connector connector; > + struct drm_plane primary_plane; > + struct drm_crtc crtc; > + struct drm_encoder encoder; > +}; > + > +struct appletbdrm_plane_state { > + struct drm_shadow_plane_state base; > + struct appletbdrm_fb_request *request; > + struct appletbdrm_fb_request_response *response; > + size_t request_size; > + size_t frames_size; > +}; > + > +static inline struct appletbdrm_plane_state *to_appletbdrm_plane_state(struct drm_plane_state *state) > +{ > + return container_of(state, struct appletbdrm_plane_state, base.base); > +} > + > +static int appletbdrm_send_request(struct appletbdrm_device *adev, > + struct appletbdrm_msg_request_header *request, size_t size) > +{ > + struct usb_device *udev = adev_to_udev(adev); > + struct drm_device *drm = &adev->drm; > + int ret, actual_size; > + > + ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, adev->out_ep), > + request, size, &actual_size, APPLETBDRM_BULK_MSG_TIMEOUT); > + if (ret) { > + drm_err(drm, "Failed to send message (%d)\n", ret); > + return ret; > + } > + > + if (actual_size != size) { > + drm_err(drm, "Actual size (%d) doesn't match expected size (%lu)\n", > + actual_size, size); > + return -EIO; > + } > + > + return 0; > +} > + > +static int appletbdrm_read_response(struct appletbdrm_device *adev, > + struct appletbdrm_msg_response_header *response, > + size_t size, __le32 expected_response) > +{ > + struct usb_device *udev = adev_to_udev(adev); > + struct drm_device *drm = &adev->drm; > + int ret, actual_size; > + bool readiness_signal_received = false; > + > +retry: > + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, adev->in_ep), > + response, size, &actual_size, APPLETBDRM_BULK_MSG_TIMEOUT); > + if (ret) { > + drm_err(drm, "Failed to read response (%d)\n", ret); > + return ret; > + } > + > + /* > + * The device responds to the first request sent in a particular > + * timeframe after the USB device configuration is set with a readiness > + * signal, in which case the response should be read again > + */ > + if (response->msg == APPLETBDRM_MSG_SIGNAL_READINESS) { > + if (!readiness_signal_received) { > + readiness_signal_received = true; > + goto retry; > + } > + > + drm_err(drm, "Encountered unexpected readiness signal\n"); > + return -EINTR; > + } > + > + if (actual_size != size) { > + drm_err(drm, "Actual size (%d) doesn't match expected size (%lu)\n", > + actual_size, size); > + return -EBADMSG; > + } > + > + if (response->msg != expected_response) { > + drm_err(drm, "Unexpected response from device (expected %p4cc found %p4cc)\n", > + &expected_response, &response->msg); > + return -EIO; > + } > + > + return 0; > +} > + > +static int appletbdrm_send_msg(struct appletbdrm_device *adev, __le32 msg) > +{ > + struct appletbdrm_msg_simple_request *request; > + int ret; > + > + request = kzalloc(sizeof(*request), GFP_KERNEL); > + if (!request) > + return -ENOMEM; > + > + request->header.unk_00 = cpu_to_le16(2); > + request->header.unk_02 = cpu_to_le16(0x1512); > + request->header.size = cpu_to_le32(sizeof(*request) - sizeof(request->header)); > + request->msg = msg; > + request->size = request->header.size; > + > + ret = appletbdrm_send_request(adev, &request->header, sizeof(*request)); > + > + kfree(request); > + > + return ret; > +} > + > +static int appletbdrm_clear_display(struct appletbdrm_device *adev) > +{ > + return appletbdrm_send_msg(adev, APPLETBDRM_MSG_CLEAR_DISPLAY); > +} > + > +static int appletbdrm_signal_readiness(struct appletbdrm_device *adev) > +{ > + return appletbdrm_send_msg(adev, APPLETBDRM_MSG_SIGNAL_READINESS); > +} > + > +static int appletbdrm_get_information(struct appletbdrm_device *adev) > +{ > + struct appletbdrm_msg_information *info; > + struct drm_device *drm = &adev->drm; > + u8 bits_per_pixel; > + __le32 pixel_format; > + int ret; > + > + info = kzalloc(sizeof(*info), GFP_KERNEL); > + if (!info) > + return -ENOMEM; > + > + ret = appletbdrm_send_msg(adev, APPLETBDRM_MSG_GET_INFORMATION); > + if (ret) > + return ret; > + > + ret = appletbdrm_read_response(adev, &info->header, sizeof(*info), > + APPLETBDRM_MSG_GET_INFORMATION); > + if (ret) > + goto free_info; > + > + bits_per_pixel = info->bits_per_pixel; > + pixel_format = get_unaligned(&info->pixel_format); > + > + adev->width = get_unaligned_le32(&info->width); > + adev->height = get_unaligned_le32(&info->height); > + > + if (bits_per_pixel != APPLETBDRM_BITS_PER_PIXEL) { > + drm_err(drm, "Encountered unexpected bits per pixel value (%d)\n", bits_per_pixel); > + ret = -EINVAL; > + goto free_info; > + } > + > + if (pixel_format != APPLETBDRM_PIXEL_FORMAT) { > + drm_err(drm, "Encountered unknown pixel format (%p4cc)\n", &pixel_format); > + ret = -EINVAL; > + goto free_info; > + } > + > +free_info: > + kfree(info); > + > + return ret; > +} > + > +static u32 rect_size(struct drm_rect *rect) > +{ > + return drm_rect_width(rect) * drm_rect_height(rect) * > + (BITS_TO_BYTES(APPLETBDRM_BITS_PER_PIXEL)); > +} > + > +static int appletbdrm_connector_helper_get_modes(struct drm_connector *connector) > +{ > + struct appletbdrm_device *adev = drm_to_adev(connector->dev); > + > + return drm_connector_helper_get_modes_fixed(connector, &adev->mode); > +} > + > +static const u32 appletbdrm_primary_plane_formats[] = { > + DRM_FORMAT_BGR888, > + DRM_FORMAT_XRGB8888, /* emulated */ > +}; > + > +static int appletbdrm_primary_plane_helper_atomic_check(struct drm_plane *plane, > + struct drm_atomic_state *state) > +{ > + struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane); > + struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane); > + struct drm_crtc *new_crtc = new_plane_state->crtc; > + struct drm_crtc_state *new_crtc_state = NULL; > + struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(new_plane_state); > + struct drm_atomic_helper_damage_iter iter; > + struct drm_rect damage; > + size_t frames_size = 0; > + size_t request_size; > + int ret; > + > + if (new_crtc) > + new_crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc); > + > + ret = drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state, > + DRM_PLANE_NO_SCALING, > + DRM_PLANE_NO_SCALING, > + false, false); > + if (ret) > + return ret; > + else if (!new_plane_state->visible) > + return 0; > + > + drm_atomic_helper_damage_iter_init(&iter, old_plane_state, new_plane_state); > + drm_atomic_for_each_plane_damage(&iter, &damage) { > + frames_size += struct_size((struct appletbdrm_frame *)0, buf, rect_size(&damage)); > + } > + > + if (!frames_size) > + return 0; > + > + request_size = ALIGN(sizeof(struct appletbdrm_fb_request) + > + frames_size + > + sizeof(struct appletbdrm_fb_request_footer), 16); > + > + appletbdrm_state->request = kzalloc(request_size, GFP_KERNEL); > + > + if (!appletbdrm_state->request) > + return -ENOMEM; > + > + appletbdrm_state->response = kzalloc(sizeof(*appletbdrm_state->response), GFP_KERNEL); > + > + if (!appletbdrm_state->response) > + return -ENOMEM; > + > + appletbdrm_state->request_size = request_size; > + appletbdrm_state->frames_size = frames_size; > + > + return 0; > +} > + > +static int appletbdrm_flush_damage(struct appletbdrm_device *adev, > + struct drm_plane_state *old_state, > + struct drm_plane_state *state) > +{ > + struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(state); > + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state); > + struct appletbdrm_fb_request_response *response = appletbdrm_state->response; > + struct appletbdrm_fb_request_footer *footer; > + struct drm_atomic_helper_damage_iter iter; > + struct drm_framebuffer *fb = state->fb; > + struct appletbdrm_fb_request *request = appletbdrm_state->request; > + struct drm_device *drm = &adev->drm; > + struct appletbdrm_frame *frame; > + u64 timestamp = ktime_get_ns(); > + struct drm_rect damage; > + size_t frames_size = appletbdrm_state->frames_size; > + size_t request_size = appletbdrm_state->request_size; > + int ret; > + > + if (!frames_size) > + return 0; > + > + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); > + if (ret) { > + drm_err(drm, "Failed to start CPU framebuffer access (%d)\n", ret); > + goto end_fb_cpu_access; > + } > + > + request->header.unk_00 = cpu_to_le16(2); > + request->header.unk_02 = cpu_to_le16(0x12); > + request->header.unk_04 = cpu_to_le32(9); > + request->header.size = cpu_to_le32(request_size - sizeof(request->header)); > + request->unk_10 = cpu_to_le16(1); > + request->msg_id = timestamp; > + > + frame = (struct appletbdrm_frame *)request->data; > + > + drm_atomic_helper_damage_iter_init(&iter, old_state, state); > + drm_atomic_for_each_plane_damage(&iter, &damage) { > + struct drm_rect dst_clip = state->dst; > + struct iosys_map dst = IOSYS_MAP_INIT_VADDR(frame->buf); > + u32 buf_size = rect_size(&damage); > + > + if (!drm_rect_intersect(&dst_clip, &damage)) > + continue; > + > + /* > + * The coordinates need to be translated to the coordinate > + * system the device expects, see the comment in > + * appletbdrm_setup_mode_config > + */ > + frame->begin_x = cpu_to_le16(damage.y1); > + frame->begin_y = cpu_to_le16(adev->height - damage.x2); > + frame->width = cpu_to_le16(drm_rect_height(&damage)); > + frame->height = cpu_to_le16(drm_rect_width(&damage)); > + frame->buf_size = cpu_to_le32(buf_size); > + > + switch (fb->format->format) { > + case DRM_FORMAT_XRGB8888: > + drm_fb_xrgb8888_to_bgr888(&dst, NULL, &shadow_plane_state->data[0], fb, &damage, &shadow_plane_state->fmtcnv_state); > + break; > + default: > + drm_fb_memcpy(&dst, NULL, &shadow_plane_state->data[0], fb, &damage); > + break; > + } > + > + frame = (void *)frame + struct_size(frame, buf, buf_size); > + } > + > + footer = (struct appletbdrm_fb_request_footer *)&request->data[frames_size]; > + > + footer->unk_0c = cpu_to_le32(0xfffe); > + footer->unk_1c = cpu_to_le32(0x80001); > + footer->unk_34 = cpu_to_le32(0x80002); > + footer->unk_4c = cpu_to_le32(0xffff); > + footer->timestamp = cpu_to_le64(timestamp); > + > + ret = appletbdrm_send_request(adev, &request->header, request_size); > + if (ret) > + goto end_fb_cpu_access; > + > + ret = appletbdrm_read_response(adev, &response->header, sizeof(*response), > + APPLETBDRM_MSG_UPDATE_COMPLETE); > + if (ret) > + goto end_fb_cpu_access; > + > + if (response->timestamp != footer->timestamp) { > + drm_err(drm, "Response timestamp (%llu) doesn't match request timestamp (%llu)\n", > + le64_to_cpu(response->timestamp), timestamp); > + goto end_fb_cpu_access; > + } > + > +end_fb_cpu_access: > + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); > + > + return ret; > +} > + > +static void appletbdrm_primary_plane_helper_atomic_update(struct drm_plane *plane, > + struct drm_atomic_state *old_state) > +{ > + struct appletbdrm_device *adev = drm_to_adev(plane->dev); > + struct drm_device *drm = plane->dev; > + struct drm_plane_state *plane_state = plane->state; > + struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(old_state, plane); > + int idx; > + > + if (!drm_dev_enter(drm, &idx)) > + return; > + > + appletbdrm_flush_damage(adev, old_plane_state, plane_state); > + > + drm_dev_exit(idx); > +} > + > +static void appletbdrm_primary_plane_helper_atomic_disable(struct drm_plane *plane, > + struct drm_atomic_state *state) > +{ > + struct drm_device *dev = plane->dev; > + struct appletbdrm_device *adev = drm_to_adev(dev); > + int idx; > + > + if (!drm_dev_enter(dev, &idx)) > + return; > + > + appletbdrm_clear_display(adev); > + > + drm_dev_exit(idx); > +} > + > +static void appletbdrm_primary_plane_reset(struct drm_plane *plane) > +{ > + struct appletbdrm_plane_state *appletbdrm_state; > + > + WARN_ON(plane->state); > + > + appletbdrm_state = kzalloc(sizeof(*appletbdrm_state), GFP_KERNEL); > + if (!appletbdrm_state) > + return; > + > + __drm_gem_reset_shadow_plane(plane, &appletbdrm_state->base); > +} > + > +static struct drm_plane_state *appletbdrm_primary_plane_duplicate_state(struct drm_plane *plane) > +{ > + struct drm_shadow_plane_state *new_shadow_plane_state; > + struct appletbdrm_plane_state *appletbdrm_state; > + > + if (WARN_ON(!plane->state)) > + return NULL; > + > + appletbdrm_state = kzalloc(sizeof(*appletbdrm_state), GFP_KERNEL); > + if (!appletbdrm_state) > + return NULL; > + > + /* Request and response are not duplicated and are allocated in .atomic_check */ > + appletbdrm_state->request = NULL; > + appletbdrm_state->response = NULL; > + > + appletbdrm_state->request_size = 0; > + appletbdrm_state->frames_size = 0; > + > + new_shadow_plane_state = &appletbdrm_state->base; > + > + __drm_gem_duplicate_shadow_plane_state(plane, new_shadow_plane_state); > + > + return &new_shadow_plane_state->base; > +} > + > +static void appletbdrm_primary_plane_destroy_state(struct drm_plane *plane, > + struct drm_plane_state *state) > +{ > + struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(state); > + > + kfree(appletbdrm_state->request); > + kfree(appletbdrm_state->response); > + > + __drm_gem_destroy_shadow_plane_state(&appletbdrm_state->base); > + > + kfree(appletbdrm_state); > +} > + > +static const struct drm_plane_helper_funcs appletbdrm_primary_plane_helper_funcs = { > + DRM_GEM_SHADOW_PLANE_HELPER_FUNCS, > + .atomic_check = appletbdrm_primary_plane_helper_atomic_check, > + .atomic_update = appletbdrm_primary_plane_helper_atomic_update, > + .atomic_disable = appletbdrm_primary_plane_helper_atomic_disable, > +}; > + > +static const struct drm_plane_funcs appletbdrm_primary_plane_funcs = { > + .update_plane = drm_atomic_helper_update_plane, > + .disable_plane = drm_atomic_helper_disable_plane, > + .reset = appletbdrm_primary_plane_reset, > + .atomic_duplicate_state = appletbdrm_primary_plane_duplicate_state, > + .atomic_destroy_state = appletbdrm_primary_plane_destroy_state, > + .destroy = drm_plane_cleanup, > +}; > + > +static enum drm_mode_status appletbdrm_crtc_helper_mode_valid(struct drm_crtc *crtc, > + const struct drm_display_mode *mode) > +{ > + struct appletbdrm_device *adev = drm_to_adev(crtc->dev); > + > + return drm_crtc_helper_mode_valid_fixed(crtc, mode, &adev->mode); > +} > + > +static const struct drm_mode_config_funcs appletbdrm_mode_config_funcs = { > + .fb_create = drm_gem_fb_create_with_dirty, > + .atomic_check = drm_atomic_helper_check, > + .atomic_commit = drm_atomic_helper_commit, > +}; > + > +static const struct drm_connector_funcs appletbdrm_connector_funcs = { > + .reset = drm_atomic_helper_connector_reset, > + .destroy = drm_connector_cleanup, > + .fill_modes = drm_helper_probe_single_connector_modes, > + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, > + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, > +}; > + > +static const struct drm_connector_helper_funcs appletbdrm_connector_helper_funcs = { > + .get_modes = appletbdrm_connector_helper_get_modes, > +}; > + > +static const struct drm_crtc_helper_funcs appletbdrm_crtc_helper_funcs = { > + .mode_valid = appletbdrm_crtc_helper_mode_valid, > +}; > + > +static const struct drm_crtc_funcs appletbdrm_crtc_funcs = { > + .reset = drm_atomic_helper_crtc_reset, > + .destroy = drm_crtc_cleanup, > + .set_config = drm_atomic_helper_set_config, > + .page_flip = drm_atomic_helper_page_flip, > + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state, > + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state, > +}; > + > +static const struct drm_encoder_funcs appletbdrm_encoder_funcs = { > + .destroy = drm_encoder_cleanup, > +}; > + > +static struct drm_gem_object *appletbdrm_driver_gem_prime_import(struct drm_device *dev, > + struct dma_buf *dma_buf) > +{ > + struct appletbdrm_device *adev = drm_to_adev(dev); > + > + if (!adev->dmadev) > + return ERR_PTR(-ENODEV); > + > + return drm_gem_prime_import_dev(dev, dma_buf, adev->dmadev); > +} > + > +DEFINE_DRM_GEM_FOPS(appletbdrm_drm_fops); > + > +static const struct drm_driver appletbdrm_drm_driver = { > + DRM_GEM_SHMEM_DRIVER_OPS, > + .gem_prime_import = appletbdrm_driver_gem_prime_import, > + .name = "appletbdrm", > + .desc = "Apple Touch Bar DRM Driver", > + .major = 1, > + .minor = 0, > + .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, > + .fops = &appletbdrm_drm_fops, > +}; > + > +static int appletbdrm_setup_mode_config(struct appletbdrm_device *adev) > +{ > + struct drm_connector *connector = &adev->connector; > + struct drm_plane *primary_plane; > + struct drm_crtc *crtc; > + struct drm_encoder *encoder; > + struct drm_device *drm = &adev->drm; > + int ret; > + > + ret = drmm_mode_config_init(drm); > + if (ret) { > + drm_err(drm, "Failed to initialize mode configuration\n"); > + return ret; > + } > + > + primary_plane = &adev->primary_plane; > + ret = drm_universal_plane_init(drm, primary_plane, 0, > + &appletbdrm_primary_plane_funcs, > + appletbdrm_primary_plane_formats, > + ARRAY_SIZE(appletbdrm_primary_plane_formats), > + NULL, > + DRM_PLANE_TYPE_PRIMARY, NULL); > + if (ret) { > + drm_err(drm, "Failed to initialize universal plane object\n"); > + return ret; > + } > + > + drm_plane_helper_add(primary_plane, &appletbdrm_primary_plane_helper_funcs); > + drm_plane_enable_fb_damage_clips(primary_plane); > + > + crtc = &adev->crtc; > + ret = drm_crtc_init_with_planes(drm, crtc, primary_plane, NULL, > + &appletbdrm_crtc_funcs, NULL); > + if (ret) { > + drm_err(drm, "Failed to initialize CRTC object\n"); > + return ret; > + } > + > + drm_crtc_helper_add(crtc, &appletbdrm_crtc_helper_funcs); > + > + encoder = &adev->encoder; > + ret = drm_encoder_init(drm, encoder, &appletbdrm_encoder_funcs, > + DRM_MODE_ENCODER_DAC, NULL); > + if (ret) { > + drm_err(drm, "Failed to initialize encoder\n"); > + return ret; > + } > + > + encoder->possible_crtcs = drm_crtc_mask(crtc); > + > + /* > + * The coordinate system used by the device is different from the > + * coordinate system of the framebuffer in that the x and y axes are > + * swapped, and that the y axis is inverted; so what the device reports > + * as the height is actually the width of the framebuffer and vice > + * versa. > + */ > + drm->mode_config.max_width = max(adev->height, DRM_SHADOW_PLANE_MAX_WIDTH); > + drm->mode_config.max_height = max(adev->width, DRM_SHADOW_PLANE_MAX_HEIGHT); > + drm->mode_config.preferred_depth = APPLETBDRM_BITS_PER_PIXEL; > + drm->mode_config.funcs = &appletbdrm_mode_config_funcs; > + > + adev->mode = (struct drm_display_mode) { > + DRM_MODE_INIT(60, adev->height, adev->width, > + DRM_MODE_RES_MM(adev->height, 218), > + DRM_MODE_RES_MM(adev->width, 218)) > + }; > + > + ret = drm_connector_init(drm, connector, > + &appletbdrm_connector_funcs, DRM_MODE_CONNECTOR_USB); > + if (ret) { > + drm_err(drm, "Failed to initialize connector\n"); > + return ret; > + } > + > + drm_connector_helper_add(connector, &appletbdrm_connector_helper_funcs); > + > + ret = drm_connector_set_panel_orientation(connector, > + DRM_MODE_PANEL_ORIENTATION_RIGHT_UP); > + if (ret) { > + drm_err(drm, "Failed to set panel orientation\n"); > + return ret; > + } > + > + connector->display_info.non_desktop = true; > + ret = drm_object_property_set_value(&connector->base, > + drm->mode_config.non_desktop_property, true); > + if (ret) { > + drm_err(drm, "Failed to set non-desktop property\n"); > + return ret; > + } > + > + ret = drm_connector_attach_encoder(connector, encoder); > + > + if (ret) { > + drm_err(drm, "Failed to initialize simple display pipe\n"); > + return ret; > + } > + > + drm_mode_config_reset(drm); > + > + return 0; > +} > + > +static int appletbdrm_probe(struct usb_interface *intf, > + const struct usb_device_id *id) > +{ > + struct usb_endpoint_descriptor *bulk_in, *bulk_out; > + struct device *dev = &intf->dev; > + struct appletbdrm_device *adev; > + struct drm_device *drm = NULL; > + int ret; > + > + ret = usb_find_common_endpoints(intf->cur_altsetting, &bulk_in, &bulk_out, NULL, NULL); > + if (ret) { > + drm_err(drm, "appletbdrm: Failed to find bulk endpoints\n"); > + return ret; > + } > + > + adev = devm_drm_dev_alloc(dev, &appletbdrm_drm_driver, struct appletbdrm_device, drm); > + if (IS_ERR(adev)) > + return PTR_ERR(adev); > + > + adev->in_ep = bulk_in->bEndpointAddress; > + adev->out_ep = bulk_out->bEndpointAddress; > + adev->dmadev = dev; > + > + drm = &adev->drm; > + > + usb_set_intfdata(intf, adev); > + > + ret = appletbdrm_get_information(adev); > + if (ret) { > + drm_err(drm, "Failed to get display information\n"); > + return ret; > + } > + > + ret = appletbdrm_signal_readiness(adev); > + if (ret) { > + drm_err(drm, "Failed to signal readiness\n"); > + return ret; > + } > + > + ret = appletbdrm_setup_mode_config(adev); > + if (ret) { > + drm_err(drm, "Failed to setup mode config\n"); > + return ret; > + } > + > + ret = drm_dev_register(drm, 0); > + if (ret) { > + drm_err(drm, "Failed to register DRM device\n"); > + return ret; > + } > + > + ret = appletbdrm_clear_display(adev); > + if (ret) { > + drm_err(drm, "Failed to clear display\n"); > + return ret; > + } > + > + return 0; > +} > + > +static void appletbdrm_disconnect(struct usb_interface *intf) > +{ > + struct appletbdrm_device *adev = usb_get_intfdata(intf); > + struct drm_device *drm = &adev->drm; > + > + put_device(adev->dmadev); > + drm_dev_unplug(drm); > + drm_atomic_helper_shutdown(drm); > +} > + > +static void appletbdrm_shutdown(struct usb_interface *intf) > +{ > + struct appletbdrm_device *adev = usb_get_intfdata(intf); > + > + /* > + * The framebuffer needs to be cleared on shutdown since its content > + * persists across boots > + */ > + drm_atomic_helper_shutdown(&adev->drm); > +} > + > +static const struct usb_device_id appletbdrm_usb_id_table[] = { > + { USB_DEVICE_INTERFACE_CLASS(0x05ac, 0x8302, USB_CLASS_AUDIO_VIDEO) }, > + {} > +}; > +MODULE_DEVICE_TABLE(usb, appletbdrm_usb_id_table); > + > +static struct usb_driver appletbdrm_usb_driver = { > + .name = "appletbdrm", > + .probe = appletbdrm_probe, > + .disconnect = appletbdrm_disconnect, > + .shutdown = appletbdrm_shutdown, > + .id_table = appletbdrm_usb_id_table, > +}; > +module_usb_driver(appletbdrm_usb_driver); > + > +MODULE_AUTHOR("Kerem Karabay <kekrby@gmail.com>"); > +MODULE_DESCRIPTION("Apple Touch Bar DRM Driver"); > +MODULE_LICENSE("GPL");
> On 27 Feb 2025, at 3:04 PM, Thomas Zimmermann <tzimmermann@suse.de> wrote: > > Hi > >> Am 26.02.25 um 17:04 schrieb Aditya Garg: >> From: Kerem Karabay <kekrby@gmail.com> >> >> The Touch Bars found on x86 Macs support two USB configurations: one >> where the device presents itself as a HID keyboard and can display >> predefined sets of keys, and one where the operating system has full >> control over what is displayed. >> >> This commit adds support for the display functionality of the second >> configuration. Functionality for the first configuration has been >> merged in the HID tree. >> >> Note that this driver has only been tested on T2 Macs, and only includes >> the USB device ID for these devices. Testing on T1 Macs would be >> appreciated. >> >> Credit goes to Ben (Bingxing) Wang on GitHub for reverse engineering >> most of the protocol. >> >> Also, as requested by Andy, I would like to clarify the use of __packed >> structs in this driver: >> >> - All the packed structs are aligned except for appletbdrm_msg_information. >> - We have to pack appletbdrm_msg_information since it is requirement of >> the protocol. >> - We compared binaries compiled by keeping the rest structs __packed and >> not __packed using bloat-o-meter, and __packed was not affecting code >> generation. >> - To maintain consistency, rest structs have been kept __packed. >> >> I would also like to point out that since the driver was reverse-engineered >> the actual data types of the protocol might be different, including, but >> not limited to, endianness. >> >> Link: https://github.com/imbushuo/DFRDisplayKm >> Signed-off-by: Kerem Karabay <kekrby@gmail.com> >> Co-developed-by: Atharva Tiwari <evepolonium@gmail.com> >> Signed-off-by: Atharva Tiwari <evepolonium@gmail.com> >> Co-developed-by: Aditya Garg <gargaditya08@live.com> >> Signed-off-by: Aditya Garg <gargaditya08@live.com> >> Signed-off-by: Aun-Ali Zaidi <admin@kodeit.net> > > Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> > > Thanks for the effort. As far as I'm concerned, this driver looks good. If no further comments come in, I can add it to the DRM tree in a few days. Thanks a lot Thomas, as well as Andy for reviewing the driver and making it better!
diff --git a/MAINTAINERS b/MAINTAINERS index efee40ea5..f7c97eb24 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7148,6 +7148,14 @@ S: Supported T: git https://gitlab.freedesktop.org/drm/misc/kernel.git F: drivers/gpu/drm/sun4i/sun8i* +DRM DRIVER FOR APPLE TOUCH BARS +M: Aun-Ali Zaidi <admin@kodeit.net> +M: Aditya Garg <gargaditya08@live.com> +L: dri-devel@lists.freedesktop.org +S: Maintained +T: git https://gitlab.freedesktop.org/drm/misc/kernel.git +F: drivers/gpu/drm/tiny/appletbdrm.c + DRM DRIVER FOR ARM PL111 CLCD M: Linus Walleij <linus.walleij@linaro.org> S: Maintained diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig index 94cbdb133..54c84c980 100644 --- a/drivers/gpu/drm/tiny/Kconfig +++ b/drivers/gpu/drm/tiny/Kconfig @@ -1,5 +1,17 @@ # SPDX-License-Identifier: GPL-2.0-only +config DRM_APPLETBDRM + tristate "DRM support for Apple Touch Bars" + depends on DRM && USB && MMU + select DRM_GEM_SHMEM_HELPER + select DRM_KMS_HELPER + help + Say Y here if you want support for the display of Touch Bars on x86 + MacBook Pros. + + To compile this driver as a module, choose M here: the + module will be called appletbdrm. + config DRM_ARCPGU tristate "ARC PGU" depends on DRM && OF diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile index 60816d2eb..0a3a7837a 100644 --- a/drivers/gpu/drm/tiny/Makefile +++ b/drivers/gpu/drm/tiny/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_DRM_APPLETBDRM) += appletbdrm.o obj-$(CONFIG_DRM_ARCPGU) += arcpgu.o obj-$(CONFIG_DRM_BOCHS) += bochs.o obj-$(CONFIG_DRM_CIRRUS_QEMU) += cirrus-qemu.o diff --git a/drivers/gpu/drm/tiny/appletbdrm.c b/drivers/gpu/drm/tiny/appletbdrm.c new file mode 100644 index 000000000..f5d177e23 --- /dev/null +++ b/drivers/gpu/drm/tiny/appletbdrm.c @@ -0,0 +1,841 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Apple Touch Bar DRM Driver + * + * Copyright (c) 2023 Kerem Karabay <kekrby@gmail.com> + */ + +#include <linux/align.h> +#include <linux/array_size.h> +#include <linux/bitops.h> +#include <linux/bug.h> +#include <linux/container_of.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/overflow.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/unaligned.h> +#include <linux/usb.h> + +#include <drm/drm_atomic.h> +#include <drm/drm_atomic_helper.h> +#include <drm/drm_crtc.h> +#include <drm/drm_damage_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_encoder.h> +#include <drm/drm_format_helper.h> +#include <drm/drm_fourcc.h> +#include <drm/drm_framebuffer.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_gem_shmem_helper.h> +#include <drm/drm_plane.h> +#include <drm/drm_print.h> +#include <drm/drm_probe_helper.h> + +#define APPLETBDRM_PIXEL_FORMAT cpu_to_le32(0x52474241) /* RGBA, the actual format is BGR888 */ +#define APPLETBDRM_BITS_PER_PIXEL 24 + +#define APPLETBDRM_MSG_CLEAR_DISPLAY cpu_to_le32(0x434c5244) /* CLRD */ +#define APPLETBDRM_MSG_GET_INFORMATION cpu_to_le32(0x47494e46) /* GINF */ +#define APPLETBDRM_MSG_UPDATE_COMPLETE cpu_to_le32(0x5544434c) /* UDCL */ +#define APPLETBDRM_MSG_SIGNAL_READINESS cpu_to_le32(0x52454459) /* REDY */ + +#define APPLETBDRM_BULK_MSG_TIMEOUT 1000 + +#define drm_to_adev(_drm) container_of(_drm, struct appletbdrm_device, drm) +#define adev_to_udev(adev) interface_to_usbdev(to_usb_interface(adev->dmadev)) + +struct appletbdrm_msg_request_header { + __le16 unk_00; + __le16 unk_02; + __le32 unk_04; + __le32 unk_08; + __le32 size; +} __packed; + +struct appletbdrm_msg_response_header { + u8 unk_00[16]; + __le32 msg; +} __packed; + +struct appletbdrm_msg_simple_request { + struct appletbdrm_msg_request_header header; + __le32 msg; + u8 unk_14[8]; + __le32 size; +} __packed; + +struct appletbdrm_msg_information { + struct appletbdrm_msg_response_header header; + u8 unk_14[12]; + __le32 width; + __le32 height; + u8 bits_per_pixel; + __le32 bytes_per_row; + __le32 orientation; + __le32 bitmap_info; + __le32 pixel_format; + __le32 width_inches; /* floating point */ + __le32 height_inches; /* floating point */ +} __packed; + +struct appletbdrm_frame { + __le16 begin_x; + __le16 begin_y; + __le16 width; + __le16 height; + __le32 buf_size; + u8 buf[]; +} __packed; + +struct appletbdrm_fb_request_footer { + u8 unk_00[12]; + __le32 unk_0c; + u8 unk_10[12]; + __le32 unk_1c; + __le64 timestamp; + u8 unk_28[12]; + __le32 unk_34; + u8 unk_38[20]; + __le32 unk_4c; +} __packed; + +struct appletbdrm_fb_request { + struct appletbdrm_msg_request_header header; + __le16 unk_10; + u8 msg_id; + u8 unk_13[29]; + /* + * Contents of `data`: + * - struct appletbdrm_frame frames[]; + * - struct appletbdrm_fb_request_footer footer; + * - padding to make the total size a multiple of 16 + */ + u8 data[]; +} __packed; + +struct appletbdrm_fb_request_response { + struct appletbdrm_msg_response_header header; + u8 unk_14[12]; + __le64 timestamp; +} __packed; + +struct appletbdrm_device { + struct device *dmadev; + + unsigned int in_ep; + unsigned int out_ep; + + unsigned int width; + unsigned int height; + + struct drm_device drm; + struct drm_display_mode mode; + struct drm_connector connector; + struct drm_plane primary_plane; + struct drm_crtc crtc; + struct drm_encoder encoder; +}; + +struct appletbdrm_plane_state { + struct drm_shadow_plane_state base; + struct appletbdrm_fb_request *request; + struct appletbdrm_fb_request_response *response; + size_t request_size; + size_t frames_size; +}; + +static inline struct appletbdrm_plane_state *to_appletbdrm_plane_state(struct drm_plane_state *state) +{ + return container_of(state, struct appletbdrm_plane_state, base.base); +} + +static int appletbdrm_send_request(struct appletbdrm_device *adev, + struct appletbdrm_msg_request_header *request, size_t size) +{ + struct usb_device *udev = adev_to_udev(adev); + struct drm_device *drm = &adev->drm; + int ret, actual_size; + + ret = usb_bulk_msg(udev, usb_sndbulkpipe(udev, adev->out_ep), + request, size, &actual_size, APPLETBDRM_BULK_MSG_TIMEOUT); + if (ret) { + drm_err(drm, "Failed to send message (%d)\n", ret); + return ret; + } + + if (actual_size != size) { + drm_err(drm, "Actual size (%d) doesn't match expected size (%lu)\n", + actual_size, size); + return -EIO; + } + + return 0; +} + +static int appletbdrm_read_response(struct appletbdrm_device *adev, + struct appletbdrm_msg_response_header *response, + size_t size, __le32 expected_response) +{ + struct usb_device *udev = adev_to_udev(adev); + struct drm_device *drm = &adev->drm; + int ret, actual_size; + bool readiness_signal_received = false; + +retry: + ret = usb_bulk_msg(udev, usb_rcvbulkpipe(udev, adev->in_ep), + response, size, &actual_size, APPLETBDRM_BULK_MSG_TIMEOUT); + if (ret) { + drm_err(drm, "Failed to read response (%d)\n", ret); + return ret; + } + + /* + * The device responds to the first request sent in a particular + * timeframe after the USB device configuration is set with a readiness + * signal, in which case the response should be read again + */ + if (response->msg == APPLETBDRM_MSG_SIGNAL_READINESS) { + if (!readiness_signal_received) { + readiness_signal_received = true; + goto retry; + } + + drm_err(drm, "Encountered unexpected readiness signal\n"); + return -EINTR; + } + + if (actual_size != size) { + drm_err(drm, "Actual size (%d) doesn't match expected size (%lu)\n", + actual_size, size); + return -EBADMSG; + } + + if (response->msg != expected_response) { + drm_err(drm, "Unexpected response from device (expected %p4cc found %p4cc)\n", + &expected_response, &response->msg); + return -EIO; + } + + return 0; +} + +static int appletbdrm_send_msg(struct appletbdrm_device *adev, __le32 msg) +{ + struct appletbdrm_msg_simple_request *request; + int ret; + + request = kzalloc(sizeof(*request), GFP_KERNEL); + if (!request) + return -ENOMEM; + + request->header.unk_00 = cpu_to_le16(2); + request->header.unk_02 = cpu_to_le16(0x1512); + request->header.size = cpu_to_le32(sizeof(*request) - sizeof(request->header)); + request->msg = msg; + request->size = request->header.size; + + ret = appletbdrm_send_request(adev, &request->header, sizeof(*request)); + + kfree(request); + + return ret; +} + +static int appletbdrm_clear_display(struct appletbdrm_device *adev) +{ + return appletbdrm_send_msg(adev, APPLETBDRM_MSG_CLEAR_DISPLAY); +} + +static int appletbdrm_signal_readiness(struct appletbdrm_device *adev) +{ + return appletbdrm_send_msg(adev, APPLETBDRM_MSG_SIGNAL_READINESS); +} + +static int appletbdrm_get_information(struct appletbdrm_device *adev) +{ + struct appletbdrm_msg_information *info; + struct drm_device *drm = &adev->drm; + u8 bits_per_pixel; + __le32 pixel_format; + int ret; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + ret = appletbdrm_send_msg(adev, APPLETBDRM_MSG_GET_INFORMATION); + if (ret) + return ret; + + ret = appletbdrm_read_response(adev, &info->header, sizeof(*info), + APPLETBDRM_MSG_GET_INFORMATION); + if (ret) + goto free_info; + + bits_per_pixel = info->bits_per_pixel; + pixel_format = get_unaligned(&info->pixel_format); + + adev->width = get_unaligned_le32(&info->width); + adev->height = get_unaligned_le32(&info->height); + + if (bits_per_pixel != APPLETBDRM_BITS_PER_PIXEL) { + drm_err(drm, "Encountered unexpected bits per pixel value (%d)\n", bits_per_pixel); + ret = -EINVAL; + goto free_info; + } + + if (pixel_format != APPLETBDRM_PIXEL_FORMAT) { + drm_err(drm, "Encountered unknown pixel format (%p4cc)\n", &pixel_format); + ret = -EINVAL; + goto free_info; + } + +free_info: + kfree(info); + + return ret; +} + +static u32 rect_size(struct drm_rect *rect) +{ + return drm_rect_width(rect) * drm_rect_height(rect) * + (BITS_TO_BYTES(APPLETBDRM_BITS_PER_PIXEL)); +} + +static int appletbdrm_connector_helper_get_modes(struct drm_connector *connector) +{ + struct appletbdrm_device *adev = drm_to_adev(connector->dev); + + return drm_connector_helper_get_modes_fixed(connector, &adev->mode); +} + +static const u32 appletbdrm_primary_plane_formats[] = { + DRM_FORMAT_BGR888, + DRM_FORMAT_XRGB8888, /* emulated */ +}; + +static int appletbdrm_primary_plane_helper_atomic_check(struct drm_plane *plane, + struct drm_atomic_state *state) +{ + struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane); + struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane); + struct drm_crtc *new_crtc = new_plane_state->crtc; + struct drm_crtc_state *new_crtc_state = NULL; + struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(new_plane_state); + struct drm_atomic_helper_damage_iter iter; + struct drm_rect damage; + size_t frames_size = 0; + size_t request_size; + int ret; + + if (new_crtc) + new_crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc); + + ret = drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state, + DRM_PLANE_NO_SCALING, + DRM_PLANE_NO_SCALING, + false, false); + if (ret) + return ret; + else if (!new_plane_state->visible) + return 0; + + drm_atomic_helper_damage_iter_init(&iter, old_plane_state, new_plane_state); + drm_atomic_for_each_plane_damage(&iter, &damage) { + frames_size += struct_size((struct appletbdrm_frame *)0, buf, rect_size(&damage)); + } + + if (!frames_size) + return 0; + + request_size = ALIGN(sizeof(struct appletbdrm_fb_request) + + frames_size + + sizeof(struct appletbdrm_fb_request_footer), 16); + + appletbdrm_state->request = kzalloc(request_size, GFP_KERNEL); + + if (!appletbdrm_state->request) + return -ENOMEM; + + appletbdrm_state->response = kzalloc(sizeof(*appletbdrm_state->response), GFP_KERNEL); + + if (!appletbdrm_state->response) + return -ENOMEM; + + appletbdrm_state->request_size = request_size; + appletbdrm_state->frames_size = frames_size; + + return 0; +} + +static int appletbdrm_flush_damage(struct appletbdrm_device *adev, + struct drm_plane_state *old_state, + struct drm_plane_state *state) +{ + struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(state); + struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state); + struct appletbdrm_fb_request_response *response = appletbdrm_state->response; + struct appletbdrm_fb_request_footer *footer; + struct drm_atomic_helper_damage_iter iter; + struct drm_framebuffer *fb = state->fb; + struct appletbdrm_fb_request *request = appletbdrm_state->request; + struct drm_device *drm = &adev->drm; + struct appletbdrm_frame *frame; + u64 timestamp = ktime_get_ns(); + struct drm_rect damage; + size_t frames_size = appletbdrm_state->frames_size; + size_t request_size = appletbdrm_state->request_size; + int ret; + + if (!frames_size) + return 0; + + ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); + if (ret) { + drm_err(drm, "Failed to start CPU framebuffer access (%d)\n", ret); + goto end_fb_cpu_access; + } + + request->header.unk_00 = cpu_to_le16(2); + request->header.unk_02 = cpu_to_le16(0x12); + request->header.unk_04 = cpu_to_le32(9); + request->header.size = cpu_to_le32(request_size - sizeof(request->header)); + request->unk_10 = cpu_to_le16(1); + request->msg_id = timestamp; + + frame = (struct appletbdrm_frame *)request->data; + + drm_atomic_helper_damage_iter_init(&iter, old_state, state); + drm_atomic_for_each_plane_damage(&iter, &damage) { + struct drm_rect dst_clip = state->dst; + struct iosys_map dst = IOSYS_MAP_INIT_VADDR(frame->buf); + u32 buf_size = rect_size(&damage); + + if (!drm_rect_intersect(&dst_clip, &damage)) + continue; + + /* + * The coordinates need to be translated to the coordinate + * system the device expects, see the comment in + * appletbdrm_setup_mode_config + */ + frame->begin_x = cpu_to_le16(damage.y1); + frame->begin_y = cpu_to_le16(adev->height - damage.x2); + frame->width = cpu_to_le16(drm_rect_height(&damage)); + frame->height = cpu_to_le16(drm_rect_width(&damage)); + frame->buf_size = cpu_to_le32(buf_size); + + switch (fb->format->format) { + case DRM_FORMAT_XRGB8888: + drm_fb_xrgb8888_to_bgr888(&dst, NULL, &shadow_plane_state->data[0], fb, &damage, &shadow_plane_state->fmtcnv_state); + break; + default: + drm_fb_memcpy(&dst, NULL, &shadow_plane_state->data[0], fb, &damage); + break; + } + + frame = (void *)frame + struct_size(frame, buf, buf_size); + } + + footer = (struct appletbdrm_fb_request_footer *)&request->data[frames_size]; + + footer->unk_0c = cpu_to_le32(0xfffe); + footer->unk_1c = cpu_to_le32(0x80001); + footer->unk_34 = cpu_to_le32(0x80002); + footer->unk_4c = cpu_to_le32(0xffff); + footer->timestamp = cpu_to_le64(timestamp); + + ret = appletbdrm_send_request(adev, &request->header, request_size); + if (ret) + goto end_fb_cpu_access; + + ret = appletbdrm_read_response(adev, &response->header, sizeof(*response), + APPLETBDRM_MSG_UPDATE_COMPLETE); + if (ret) + goto end_fb_cpu_access; + + if (response->timestamp != footer->timestamp) { + drm_err(drm, "Response timestamp (%llu) doesn't match request timestamp (%llu)\n", + le64_to_cpu(response->timestamp), timestamp); + goto end_fb_cpu_access; + } + +end_fb_cpu_access: + drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); + + return ret; +} + +static void appletbdrm_primary_plane_helper_atomic_update(struct drm_plane *plane, + struct drm_atomic_state *old_state) +{ + struct appletbdrm_device *adev = drm_to_adev(plane->dev); + struct drm_device *drm = plane->dev; + struct drm_plane_state *plane_state = plane->state; + struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(old_state, plane); + int idx; + + if (!drm_dev_enter(drm, &idx)) + return; + + appletbdrm_flush_damage(adev, old_plane_state, plane_state); + + drm_dev_exit(idx); +} + +static void appletbdrm_primary_plane_helper_atomic_disable(struct drm_plane *plane, + struct drm_atomic_state *state) +{ + struct drm_device *dev = plane->dev; + struct appletbdrm_device *adev = drm_to_adev(dev); + int idx; + + if (!drm_dev_enter(dev, &idx)) + return; + + appletbdrm_clear_display(adev); + + drm_dev_exit(idx); +} + +static void appletbdrm_primary_plane_reset(struct drm_plane *plane) +{ + struct appletbdrm_plane_state *appletbdrm_state; + + WARN_ON(plane->state); + + appletbdrm_state = kzalloc(sizeof(*appletbdrm_state), GFP_KERNEL); + if (!appletbdrm_state) + return; + + __drm_gem_reset_shadow_plane(plane, &appletbdrm_state->base); +} + +static struct drm_plane_state *appletbdrm_primary_plane_duplicate_state(struct drm_plane *plane) +{ + struct drm_shadow_plane_state *new_shadow_plane_state; + struct appletbdrm_plane_state *appletbdrm_state; + + if (WARN_ON(!plane->state)) + return NULL; + + appletbdrm_state = kzalloc(sizeof(*appletbdrm_state), GFP_KERNEL); + if (!appletbdrm_state) + return NULL; + + /* Request and response are not duplicated and are allocated in .atomic_check */ + appletbdrm_state->request = NULL; + appletbdrm_state->response = NULL; + + appletbdrm_state->request_size = 0; + appletbdrm_state->frames_size = 0; + + new_shadow_plane_state = &appletbdrm_state->base; + + __drm_gem_duplicate_shadow_plane_state(plane, new_shadow_plane_state); + + return &new_shadow_plane_state->base; +} + +static void appletbdrm_primary_plane_destroy_state(struct drm_plane *plane, + struct drm_plane_state *state) +{ + struct appletbdrm_plane_state *appletbdrm_state = to_appletbdrm_plane_state(state); + + kfree(appletbdrm_state->request); + kfree(appletbdrm_state->response); + + __drm_gem_destroy_shadow_plane_state(&appletbdrm_state->base); + + kfree(appletbdrm_state); +} + +static const struct drm_plane_helper_funcs appletbdrm_primary_plane_helper_funcs = { + DRM_GEM_SHADOW_PLANE_HELPER_FUNCS, + .atomic_check = appletbdrm_primary_plane_helper_atomic_check, + .atomic_update = appletbdrm_primary_plane_helper_atomic_update, + .atomic_disable = appletbdrm_primary_plane_helper_atomic_disable, +}; + +static const struct drm_plane_funcs appletbdrm_primary_plane_funcs = { + .update_plane = drm_atomic_helper_update_plane, + .disable_plane = drm_atomic_helper_disable_plane, + .reset = appletbdrm_primary_plane_reset, + .atomic_duplicate_state = appletbdrm_primary_plane_duplicate_state, + .atomic_destroy_state = appletbdrm_primary_plane_destroy_state, + .destroy = drm_plane_cleanup, +}; + +static enum drm_mode_status appletbdrm_crtc_helper_mode_valid(struct drm_crtc *crtc, + const struct drm_display_mode *mode) +{ + struct appletbdrm_device *adev = drm_to_adev(crtc->dev); + + return drm_crtc_helper_mode_valid_fixed(crtc, mode, &adev->mode); +} + +static const struct drm_mode_config_funcs appletbdrm_mode_config_funcs = { + .fb_create = drm_gem_fb_create_with_dirty, + .atomic_check = drm_atomic_helper_check, + .atomic_commit = drm_atomic_helper_commit, +}; + +static const struct drm_connector_funcs appletbdrm_connector_funcs = { + .reset = drm_atomic_helper_connector_reset, + .destroy = drm_connector_cleanup, + .fill_modes = drm_helper_probe_single_connector_modes, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, +}; + +static const struct drm_connector_helper_funcs appletbdrm_connector_helper_funcs = { + .get_modes = appletbdrm_connector_helper_get_modes, +}; + +static const struct drm_crtc_helper_funcs appletbdrm_crtc_helper_funcs = { + .mode_valid = appletbdrm_crtc_helper_mode_valid, +}; + +static const struct drm_crtc_funcs appletbdrm_crtc_funcs = { + .reset = drm_atomic_helper_crtc_reset, + .destroy = drm_crtc_cleanup, + .set_config = drm_atomic_helper_set_config, + .page_flip = drm_atomic_helper_page_flip, + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state, +}; + +static const struct drm_encoder_funcs appletbdrm_encoder_funcs = { + .destroy = drm_encoder_cleanup, +}; + +static struct drm_gem_object *appletbdrm_driver_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf) +{ + struct appletbdrm_device *adev = drm_to_adev(dev); + + if (!adev->dmadev) + return ERR_PTR(-ENODEV); + + return drm_gem_prime_import_dev(dev, dma_buf, adev->dmadev); +} + +DEFINE_DRM_GEM_FOPS(appletbdrm_drm_fops); + +static const struct drm_driver appletbdrm_drm_driver = { + DRM_GEM_SHMEM_DRIVER_OPS, + .gem_prime_import = appletbdrm_driver_gem_prime_import, + .name = "appletbdrm", + .desc = "Apple Touch Bar DRM Driver", + .major = 1, + .minor = 0, + .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, + .fops = &appletbdrm_drm_fops, +}; + +static int appletbdrm_setup_mode_config(struct appletbdrm_device *adev) +{ + struct drm_connector *connector = &adev->connector; + struct drm_plane *primary_plane; + struct drm_crtc *crtc; + struct drm_encoder *encoder; + struct drm_device *drm = &adev->drm; + int ret; + + ret = drmm_mode_config_init(drm); + if (ret) { + drm_err(drm, "Failed to initialize mode configuration\n"); + return ret; + } + + primary_plane = &adev->primary_plane; + ret = drm_universal_plane_init(drm, primary_plane, 0, + &appletbdrm_primary_plane_funcs, + appletbdrm_primary_plane_formats, + ARRAY_SIZE(appletbdrm_primary_plane_formats), + NULL, + DRM_PLANE_TYPE_PRIMARY, NULL); + if (ret) { + drm_err(drm, "Failed to initialize universal plane object\n"); + return ret; + } + + drm_plane_helper_add(primary_plane, &appletbdrm_primary_plane_helper_funcs); + drm_plane_enable_fb_damage_clips(primary_plane); + + crtc = &adev->crtc; + ret = drm_crtc_init_with_planes(drm, crtc, primary_plane, NULL, + &appletbdrm_crtc_funcs, NULL); + if (ret) { + drm_err(drm, "Failed to initialize CRTC object\n"); + return ret; + } + + drm_crtc_helper_add(crtc, &appletbdrm_crtc_helper_funcs); + + encoder = &adev->encoder; + ret = drm_encoder_init(drm, encoder, &appletbdrm_encoder_funcs, + DRM_MODE_ENCODER_DAC, NULL); + if (ret) { + drm_err(drm, "Failed to initialize encoder\n"); + return ret; + } + + encoder->possible_crtcs = drm_crtc_mask(crtc); + + /* + * The coordinate system used by the device is different from the + * coordinate system of the framebuffer in that the x and y axes are + * swapped, and that the y axis is inverted; so what the device reports + * as the height is actually the width of the framebuffer and vice + * versa. + */ + drm->mode_config.max_width = max(adev->height, DRM_SHADOW_PLANE_MAX_WIDTH); + drm->mode_config.max_height = max(adev->width, DRM_SHADOW_PLANE_MAX_HEIGHT); + drm->mode_config.preferred_depth = APPLETBDRM_BITS_PER_PIXEL; + drm->mode_config.funcs = &appletbdrm_mode_config_funcs; + + adev->mode = (struct drm_display_mode) { + DRM_MODE_INIT(60, adev->height, adev->width, + DRM_MODE_RES_MM(adev->height, 218), + DRM_MODE_RES_MM(adev->width, 218)) + }; + + ret = drm_connector_init(drm, connector, + &appletbdrm_connector_funcs, DRM_MODE_CONNECTOR_USB); + if (ret) { + drm_err(drm, "Failed to initialize connector\n"); + return ret; + } + + drm_connector_helper_add(connector, &appletbdrm_connector_helper_funcs); + + ret = drm_connector_set_panel_orientation(connector, + DRM_MODE_PANEL_ORIENTATION_RIGHT_UP); + if (ret) { + drm_err(drm, "Failed to set panel orientation\n"); + return ret; + } + + connector->display_info.non_desktop = true; + ret = drm_object_property_set_value(&connector->base, + drm->mode_config.non_desktop_property, true); + if (ret) { + drm_err(drm, "Failed to set non-desktop property\n"); + return ret; + } + + ret = drm_connector_attach_encoder(connector, encoder); + + if (ret) { + drm_err(drm, "Failed to initialize simple display pipe\n"); + return ret; + } + + drm_mode_config_reset(drm); + + return 0; +} + +static int appletbdrm_probe(struct usb_interface *intf, + const struct usb_device_id *id) +{ + struct usb_endpoint_descriptor *bulk_in, *bulk_out; + struct device *dev = &intf->dev; + struct appletbdrm_device *adev; + struct drm_device *drm = NULL; + int ret; + + ret = usb_find_common_endpoints(intf->cur_altsetting, &bulk_in, &bulk_out, NULL, NULL); + if (ret) { + drm_err(drm, "appletbdrm: Failed to find bulk endpoints\n"); + return ret; + } + + adev = devm_drm_dev_alloc(dev, &appletbdrm_drm_driver, struct appletbdrm_device, drm); + if (IS_ERR(adev)) + return PTR_ERR(adev); + + adev->in_ep = bulk_in->bEndpointAddress; + adev->out_ep = bulk_out->bEndpointAddress; + adev->dmadev = dev; + + drm = &adev->drm; + + usb_set_intfdata(intf, adev); + + ret = appletbdrm_get_information(adev); + if (ret) { + drm_err(drm, "Failed to get display information\n"); + return ret; + } + + ret = appletbdrm_signal_readiness(adev); + if (ret) { + drm_err(drm, "Failed to signal readiness\n"); + return ret; + } + + ret = appletbdrm_setup_mode_config(adev); + if (ret) { + drm_err(drm, "Failed to setup mode config\n"); + return ret; + } + + ret = drm_dev_register(drm, 0); + if (ret) { + drm_err(drm, "Failed to register DRM device\n"); + return ret; + } + + ret = appletbdrm_clear_display(adev); + if (ret) { + drm_err(drm, "Failed to clear display\n"); + return ret; + } + + return 0; +} + +static void appletbdrm_disconnect(struct usb_interface *intf) +{ + struct appletbdrm_device *adev = usb_get_intfdata(intf); + struct drm_device *drm = &adev->drm; + + put_device(adev->dmadev); + drm_dev_unplug(drm); + drm_atomic_helper_shutdown(drm); +} + +static void appletbdrm_shutdown(struct usb_interface *intf) +{ + struct appletbdrm_device *adev = usb_get_intfdata(intf); + + /* + * The framebuffer needs to be cleared on shutdown since its content + * persists across boots + */ + drm_atomic_helper_shutdown(&adev->drm); +} + +static const struct usb_device_id appletbdrm_usb_id_table[] = { + { USB_DEVICE_INTERFACE_CLASS(0x05ac, 0x8302, USB_CLASS_AUDIO_VIDEO) }, + {} +}; +MODULE_DEVICE_TABLE(usb, appletbdrm_usb_id_table); + +static struct usb_driver appletbdrm_usb_driver = { + .name = "appletbdrm", + .probe = appletbdrm_probe, + .disconnect = appletbdrm_disconnect, + .shutdown = appletbdrm_shutdown, + .id_table = appletbdrm_usb_id_table, +}; +module_usb_driver(appletbdrm_usb_driver); + +MODULE_AUTHOR("Kerem Karabay <kekrby@gmail.com>"); +MODULE_DESCRIPTION("Apple Touch Bar DRM Driver"); +MODULE_LICENSE("GPL");