// SPDX-License-Identifier: MIT
/*
* Copyright 2020 Noralf Trønnes
*/
#include <linux/dma-buf.h>
#include <linux/dma-mapping.h>
#include <linux/lz4.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/string_helpers.h>
#include <linux/usb.h>
#include <linux/vmalloc.h>
#include <linux/workqueue.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_blend.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_debugfs.h>
#include <drm/drm_drv.h>
#include <drm/drm_fbdev_shmem.h>
#include <drm/drm_fourcc.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_managed.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_simple_kms_helper.h>
#include <drm/gud.h>
#include "gud_internal.h"
/* Only used internally */
static const struct drm_format_info gud_drm_format_r1 = {
.format = GUD_DRM_FORMAT_R1,
.num_planes = 1,
.char_per_block = { 1, 0, 0 },
.block_w = { 8, 0, 0 },
.block_h = { 1, 0, 0 },
.hsub = 1,
.vsub = 1,
};
static const struct drm_format_info gud_drm_format_xrgb1111 = {
.format = GUD_DRM_FORMAT_XRGB1111,
.num_planes = 1,
.char_per_block = { 1, 0, 0 },
.block_w = { 2, 0, 0 },
.block_h = { 1, 0, 0 },
.hsub = 1,
.vsub = 1,
};
static int gud_usb_control_msg(struct usb_interface *intf, bool in,
u8 request, u16 value, void *buf, size_t len)
{
u8 requesttype = USB_TYPE_VENDOR | USB_RECIP_INTERFACE;
u8 ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
struct usb_device *usb = interface_to_usbdev(intf);
unsigned int pipe;
if (len && !buf)
return -EINVAL;
if (in) {
pipe = usb_rcvctrlpipe(usb, 0);
requesttype |= USB_DIR_IN;
} else {
pipe = usb_sndctrlpipe(usb, 0);
requesttype |= USB_DIR_OUT;
}
return usb_control_msg(usb, pipe, request, requesttype, value,
ifnum, buf, len, USB_CTRL_GET_TIMEOUT);
}
static int gud_get_display_descriptor(struct usb_interface *intf,
struct gud_display_descriptor_req *desc)
{
void *buf;
int ret;
buf = kmalloc(sizeof(*desc), GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = gud_usb_control_msg(intf, true, GUD_REQ_GET_DESCRIPTOR, 0, buf, sizeof(*desc));
memcpy(desc, buf, sizeof(*desc));
kfree(buf);
if (ret < 0)
return ret;
if (ret != sizeof(*desc))
return -EIO;
if (desc->magic != le32_to_cpu(GUD_DISPLAY_MAGIC))
return -ENODATA;
DRM_DEV_DEBUG_DRIVER(&intf->dev,
"version=%u flags=0x%x compression=0x%x max_buffer_size=%u\n",
desc->version, le32_to_cpu(desc->flags), desc->compression,
le32_to_cpu(desc->max_buffer_size));
if (!desc->version || !desc->max_width || !desc->max_height ||
le32_to_cpu(desc->min_width) > le32_to_cpu(desc->max_width) ||
le32_to_cpu(desc->min_height) > le32_to_cpu(desc->max_height))
return -EINVAL;
return 0;
}
static int gud_status_to_errno(u8 status)
{
switch (status) {
case GUD_STATUS_OK:
return 0;
case GUD_STATUS_BUSY:
return -EBUSY;
case GUD_STATUS_REQUEST_NOT_SUPPORTED:
return -EOPNOTSUPP;
case GUD_STATUS_PROTOCOL_ERROR:
return -EPROTO;
case GUD_STATUS_INVALID_PARAMETER:
return -EINVAL;
case GUD_STATUS_ERROR:
return -EREMOTEIO;
default:
return -EREMOTEIO;
}
}
static int gud_usb_get_status(struct usb_interface *intf)
{
int ret, status = -EIO;
u8 *buf;
buf = kmalloc(sizeof(*buf), GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = gud_usb_control_msg(intf, true, GUD_REQ_GET_STATUS, 0, buf, sizeof(*buf));
if (ret == sizeof(*buf))
status = gud_status_to_errno(*buf);
kfree(buf);
if (ret < 0)
return ret;
return status;
}
static int gud_usb_transfer(struct gud_device *gdrm, bool in, u8 request, u16 index,
void *buf, size_t len)
{
struct usb_interface *intf = to_usb_interface(gdrm->drm.dev);
int idx, ret;
drm_dbg(&gdrm->drm, "%s: request=0x%x index=%u len=%zu\n",
in ? "get" : "set", request, index, len);
if (!drm_dev_enter(&gdrm->drm, &idx))
return -ENODEV;
mutex_lock(&gdrm->ctrl_lock);
ret = gud_usb_control_msg(intf, in, request, index, buf, len);
if (ret == -EPIPE || ((gdrm->flags & GUD_DISPLAY_FLAG_STATUS_ON_SET) && !in && ret >= 0)) {
int status;
status = gud_usb_get_status(intf);
if (status < 0) {
ret = status;
} else if (ret < 0) {
dev_err_once(gdrm->drm.dev,
"Unexpected status OK for failed transfer\n");
ret = -EPIPE;
}
}
if (ret < 0) {
drm_dbg(&gdrm->drm, "ret=%d\n", ret);
gdrm->stats_num_errors++;
}
mutex_unlock(&gdrm->ctrl_lock);
drm_dev_exit(idx);
return ret;
}
/*
* @buf cannot be allocated on the stack.
* Returns number of bytes received or negative error code on failure.
*/
int gud_usb_get(struct gud_device *gdrm, u8 request, u16 index, void *buf, size_t max_len)
{
return gud_usb_transfer(gdrm, true, request, index, buf, max_len);
}
/*
* @buf can be allocated on the stack or NULL.
* Returns zero on success or negative error code on failure.
*/
int gud_usb_set(struct gud_device *gdrm, u8 request, u16 index, void *buf, size_t len)
{
void *trbuf = NULL;
int ret;
if (buf && len) {
trbuf = kmemdup(buf, len, GFP_KERNEL);
if (!trbuf)
return -ENOMEM;
}
ret = gud_usb_transfer(gdrm, false, request, index, trbuf, len);
kfree(trbuf);
if (ret < 0)
return ret;
return ret != len ? -EIO : 0;
}
/*
* @val can be allocated on the stack.
* Returns zero on success or negative error code on failure.
*/
int gud_usb_get_u8(struct gud_device *gdrm, u8 request, u16 index, u8 *val)
{
u8 *buf;
int ret;
buf = kmalloc(sizeof(*val), GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = gud_usb_get(gdrm, request, index, buf, sizeof(*val));
*val = *buf;
kfree(buf);
if (ret < 0)
return ret;
return ret != sizeof(*val) ? -EIO : 0;
}
/* Returns zero on success or negative error code on failure. */
int gud_usb_set_u8(struct gud_device *gdrm, u8 request, u8 val)
{
return gud_usb_set(gdrm, request, 0, &val, sizeof(val));
}
static int gud_get_properties(struct gud_device *gdrm)
{
struct gud_property_req *properties;
unsigned int i, num_properties;
int ret;
properties = kcalloc(GUD_PROPERTIES_MAX_NUM, sizeof(*properties), GFP_KERNEL);
if (!properties)
return -ENOMEM;
ret = gud_usb_get(gdrm, GUD_REQ_GET_PROPERTIES, 0,
properties, GUD_PROPERTIES_MAX_NUM * sizeof(*properties));
if (ret <= 0)
goto out;
if (ret % sizeof(*properties)) {
ret = -EIO;
goto out;
}
num_properties = ret / sizeof(*properties);
ret = 0;
gdrm->properties = drmm_kcalloc(&gdrm->drm, num_properties, sizeof(*gdrm->properties),
GFP_KERNEL);
if (!gdrm->properties) {
ret = -ENOMEM;
goto out;
}
for (i = 0; i < num_properties; i++) {
u16 prop = le16_to_cpu(properties[i].prop);
u64 val = le64_to_cpu(properties[i].val);
switch (prop) {
case GUD_PROPERTY_ROTATION:
/*
* DRM UAPI matches the protocol so use the value directly,
* but mask out any additions on future devices.
*/
val &= GUD_ROTATION_MASK;
ret = drm_plane_create_rotation_property(&gdrm->pipe.plane,
DRM_MODE_ROTATE_0, val);
break;
default:
/* New ones might show up in future devices, skip those we don't know. */
drm_dbg(&gdrm->drm, "Ignoring unknown property: %u\n", prop);
continue;
}
if (ret)
goto out;
gdrm->properties[gdrm->num_properties++] = prop;
}
out:
kfree(properties);
return ret;
}
/*
* FIXME: Dma-buf sharing requires DMA support by the importing device.
* This function is a workaround to make USB devices work as well.
* See todo.rst for how to fix the issue in the dma-buf framework.
*/
static struct drm_gem_object *gud_gem_prime_import(struct drm_device *drm, struct dma_buf *dma_buf)
{
struct gud_device *gdrm = to_gud_device(drm);
if (!gdrm->dmadev)
return ERR_PTR(-ENODEV);
return drm_gem_prime_import_dev(drm, dma_buf, gdrm->dmadev);
}
static int gud_stats_debugfs(struct seq_file *m, void *data)
{
struct drm_debugfs_entry *entry = m->private;
struct gud_device *gdrm = to_gud_device(entry->dev);
char buf[10];
string_get_size(gdrm->bulk_len, 1, STRING_UNITS_2, buf, sizeof(buf));
seq_printf(m, "Max buffer size: %s\n", buf);
seq_printf(m, "Number of errors: %u\n", gdrm->stats_num_errors);
seq_puts(m, "Compression: ");
if (gdrm->compression & GUD_COMPRESSION_LZ4)
seq_puts(m, " lz4");
if (!gdrm->compression)
seq_puts(m, " none");
seq_puts(m, "\n");
if (gdrm->compression) {
u64 remainder;
u64 ratio = div64_u64_rem(gdrm->stats_length, gdrm->stats_actual_length,
&remainder);
u64 ratio_frac = div64_u64(remainder * 10, gdrm->stats_actual_length);
seq_printf(m, "Compression ratio: %llu.%llu\n", ratio, ratio_frac);
}
return 0;
}
static const struct drm_simple_display_pipe_funcs gud_pipe_funcs = {
.check = gud_pipe_check,
.update = gud_pipe_update,
DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS
};
static const struct drm_mode_config_funcs gud_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 u64 gud_pipe_modifiers[] = {
DRM_FORMAT_MOD_LINEAR,
DRM_FORMAT_MOD_INVALID
};
DEFINE_DRM_GEM_FOPS(gud_fops);
static const struct drm_driver gud_drm_driver = {
.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
.fops = &gud_fops,
DRM_GEM_SHMEM_DRIVER_OPS,
.gem_prime_import = gud_gem_prime_import,
.name = "gud",
.desc = "Generic USB Display",
.date = "20200422",
.major = 1,
.minor = 0,
};
static int gud_alloc_bulk_buffer(struct gud_device *gdrm)
{
unsigned int i, num_pages;
struct page **pages;
void *ptr;
int ret;
gdrm->bulk_buf = vmalloc_32(gdrm->bulk_len);
if (!gdrm->bulk_buf)
return -ENOMEM;
num_pages = DIV_ROUND_UP(gdrm->bulk_len, PAGE_SIZE);
pages = kmalloc_array(num_pages, sizeof(struct page *), GFP_KERNEL);
if (!pages)
return -ENOMEM;
for (i = 0, ptr = gdrm->bulk_buf; i < num_pages; i++, ptr += PAGE_SIZE)
pages[i] = vmalloc_to_page(ptr);
ret = sg_alloc_table_from_pages(&gdrm->bulk_sgt, pages, num_pages,
0, gdrm->bulk_len, GFP_KERNEL);
kfree(pages);
return ret;
}
static void gud_free_buffers_and_mutex(void *data)
{
struct gud_device *gdrm = data;
vfree(gdrm->compress_buf);
gdrm->compress_buf = NULL;
sg_free_table(&gdrm->bulk_sgt);
vfree(gdrm->bulk_buf);
gdrm->bulk_buf = NULL;
mutex_destroy(&gdrm->ctrl_lock);
}
static int gud_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
const struct drm_format_info *xrgb8888_emulation_format = NULL;
bool rgb565_supported = false, xrgb8888_supported = false;
unsigned int num_formats_dev, num_formats = 0;
struct usb_endpoint_descriptor *bulk_out;
struct gud_display_descriptor_req desc;
struct device *dev = &intf->dev;
size_t max_buffer_size = 0;
struct gud_device *gdrm;
struct drm_device *drm;
u8 *formats_dev;
u32 *formats;
int ret, i;
ret = usb_find_bulk_out_endpoint(intf->cur_altsetting, &bulk_out);
if (ret)
return ret;
ret = gud_get_display_descriptor(intf, &desc);
if (ret) {
DRM_DEV_DEBUG_DRIVER(dev, "Not a display interface: ret=%d\n", ret);
return -ENODEV;
}
if (desc.version > 1) {
dev_err(dev, "Protocol version %u is not supported\n", desc.version);
return -ENODEV;
}
gdrm = devm_drm_dev_alloc(dev, &gud_drm_driver, struct gud_device, drm);
if (IS_ERR(gdrm))
return PTR_ERR(gdrm);
drm = &gdrm->drm;
drm->mode_config.funcs = &gud_mode_config_funcs;
ret = drmm_mode_config_init(drm);
if (ret)
return ret;
gdrm->flags = le32_to_cpu(desc.flags);
gdrm->compression = desc.compression & GUD_COMPRESSION_LZ4;
if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE && gdrm->compression)
return -EINVAL;
mutex_init(&gdrm->ctrl_lock);
mutex_init(&gdrm->damage_lock);
INIT_WORK(&gdrm->work, gud_flush_work);
gud_clear_damage(gdrm);
ret = devm_add_action(dev, gud_free_buffers_and_mutex, gdrm);
if (ret)
return ret;
drm->mode_config.min_width = le32_to_cpu(desc.min_width);
drm->mode_config.max_width = le32_to_cpu(desc.max_width);
drm->mode_config.min_height = le32_to_cpu(desc.min_height);
drm->mode_config.max_height = le32_to_cpu(desc.max_height);
formats_dev = devm_kmalloc(dev, GUD_FORMATS_MAX_NUM, GFP_KERNEL);
/* Add room for emulated XRGB8888 */
formats = devm_kmalloc_array(dev, GUD_FORMATS_MAX_NUM + 1, sizeof(*formats), GFP_KERNEL);
if (!formats_dev || !formats)
return -ENOMEM;
ret = gud_usb_get(gdrm, GUD_REQ_GET_FORMATS, 0, formats_dev, GUD_FORMATS_MAX_NUM);
if (ret < 0)
return ret;
num_formats_dev = ret;
for (i = 0; i < num_formats_dev; i++) {
const struct drm_format_info *info;
size_t fmt_buf_size;
u32 format;
format = gud_to_fourcc(formats_dev[i]);
if (!format) {
drm_dbg(drm, "Unsupported format: 0x%02x\n", formats_dev[i]);
continue;
}
if (format == GUD_DRM_FORMAT_R1)
info = &gud_drm_format_r1;
else if (format == GUD_DRM_FORMAT_XRGB1111)
info = &gud_drm_format_xrgb1111;
else
info = drm_format_info(format);
switch (format) {
case GUD_DRM_FORMAT_R1:
fallthrough;
case DRM_FORMAT_R8:
fallthrough;
case GUD_DRM_FORMAT_XRGB1111:
fallthrough;
case DRM_FORMAT_RGB332:
fallthrough;
case DRM_FORMAT_RGB888:
if (!xrgb8888_emulation_format)
xrgb8888_emulation_format = info;
break;
case DRM_FORMAT_RGB565:
rgb565_supported = true;
if (!xrgb8888_emulation_format)
xrgb8888_emulation_format = info;
break;
case DRM_FORMAT_XRGB8888:
xrgb8888_supported = true;
break;
}
fmt_buf_size = drm_format_info_min_pitch(info, 0, drm->mode_config.max_width) *
drm->mode_config.max_height;
max_buffer_size = max(max_buffer_size, fmt_buf_size);
if (format == GUD_DRM_FORMAT_R1 || format == GUD_DRM_FORMAT_XRGB1111)
continue; /* Internal not for userspace */
formats[num_formats++] = format;
}
if (!num_formats && !xrgb8888_emulation_format) {
dev_err(dev, "No supported pixel formats found\n");
return -EINVAL;
}
/* Prefer speed over color depth */
if (rgb565_supported)
drm->mode_config.preferred_depth = 16;
if (!xrgb8888_supported && xrgb8888_emulation_format) {
gdrm->xrgb8888_emulation_format = xrgb8888_emulation_format;
formats[num_formats++] = DRM_FORMAT_XRGB8888;
}
if (desc.max_buffer_size)
max_buffer_size = le32_to_cpu(desc.max_buffer_size);
/* Prevent a misbehaving device from allocating loads of RAM. 4096x4096@XRGB8888 = 64 MB */
if (max_buffer_size > SZ_64M)
max_buffer_size = SZ_64M;
gdrm->bulk_pipe = usb_sndbulkpipe(interface_to_usbdev(intf), usb_endpoint_num(bulk_out));
gdrm->bulk_len = max_buffer_size;
ret = gud_alloc_bulk_buffer(gdrm);
if (ret)
return ret;
if (gdrm->compression & GUD_COMPRESSION_LZ4) {
gdrm->lz4_comp_mem = devm_kmalloc(dev, LZ4_MEM_COMPRESS, GFP_KERNEL);
if (!gdrm->lz4_comp_mem)
return -ENOMEM;
gdrm->compress_buf = vmalloc(gdrm->bulk_len);
if (!gdrm->compress_buf)
return -ENOMEM;
}
ret = drm_simple_display_pipe_init(drm, &gdrm->pipe, &gud_pipe_funcs,
formats, num_formats,
gud_pipe_modifiers, NULL);
if (ret)
return ret;
devm_kfree(dev, formats);
devm_kfree(dev, formats_dev);
ret = gud_get_properties(gdrm);
if (ret) {
dev_err(dev, "Failed to get properties (error=%d)\n", ret);
return ret;
}
drm_plane_enable_fb_damage_clips(&gdrm->pipe.plane);
ret = gud_get_connectors(gdrm);
if (ret) {
dev_err(dev, "Failed to get connectors (error=%d)\n", ret);
return ret;
}
drm_mode_config_reset(drm);
usb_set_intfdata(intf, gdrm);
gdrm->dmadev = usb_intf_get_dma_device(intf);
if (!gdrm->dmadev)
dev_warn(dev, "buffer sharing not supported");
drm_debugfs_add_file(drm, "stats", gud_stats_debugfs, NULL);
ret = drm_dev_register(drm, 0);
if (ret) {
put_device(gdrm->dmadev);
return ret;
}
drm_kms_helper_poll_init(drm);
drm_fbdev_shmem_setup(drm, 0);
return 0;
}
static void gud_disconnect(struct usb_interface *interface)
{
struct gud_device *gdrm = usb_get_intfdata(interface);
struct drm_device *drm = &gdrm->drm;
drm_dbg(drm, "%s:\n", __func__);
drm_kms_helper_poll_fini(drm);
drm_dev_unplug(drm);
drm_atomic_helper_shutdown(drm);
put_device(gdrm->dmadev);
gdrm->dmadev = NULL;
}
static int gud_suspend(struct usb_interface *intf, pm_message_t message)
{
struct gud_device *gdrm = usb_get_intfdata(intf);
return drm_mode_config_helper_suspend(&gdrm->drm);
}
static int gud_resume(struct usb_interface *intf)
{
struct gud_device *gdrm = usb_get_intfdata(intf);
drm_mode_config_helper_resume(&gdrm->drm);
return 0;
}
static const struct usb_device_id gud_id_table[] = {
{ USB_DEVICE_INTERFACE_CLASS(0x1d50, 0x614d, USB_CLASS_VENDOR_SPEC) },
{ USB_DEVICE_INTERFACE_CLASS(0x16d0, 0x10a9, USB_CLASS_VENDOR_SPEC) },
{ }
};
MODULE_DEVICE_TABLE(usb, gud_id_table);
static struct usb_driver gud_usb_driver = {
.name = "gud",
.probe = gud_probe,
.disconnect = gud_disconnect,
.id_table = gud_id_table,
.suspend = gud_suspend,
.resume = gud_resume,
.reset_resume = gud_resume,
};
module_usb_driver(gud_usb_driver);
MODULE_AUTHOR("Noralf Trønnes");
MODULE_DESCRIPTION("GUD USB Display driver");
MODULE_LICENSE("Dual MIT/GPL");
Codebase Browser
linux