From f8484ccbd12ba33ea5b3895efb7a39d986271be0 Mon Sep 17 00:00:00 2001 From: Thierry Reding Date: Thu, 22 Dec 2016 00:39:36 +0100 Subject: [PATCH] xf86drm: Add USB support Allow DRM/KMS devices hosted on USB to be detected by the drmDevice infrastructure. v4: - continue on error to process USB devices v3: - guard Linux-specific sysfs parsing code with #ifdef __linux__ v2: - make sysfs_uevent_get() more flexible using a format string Reviewed-by: Emil Velikov Signed-off-by: Thierry Reding --- xf86drm.c | 175 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ xf86drm.h | 13 +++++ 2 files changed, 188 insertions(+) diff --git a/xf86drm.c b/xf86drm.c index 7766bfe..58e9ce0 100644 --- a/xf86drm.c +++ b/xf86drm.c @@ -2886,6 +2886,50 @@ char *drmGetRenderDeviceNameFromFd(int fd) return drmGetMinorNameForFD(fd, DRM_NODE_RENDER); } +#ifdef __linux__ +static char * DRM_PRINTFLIKE(2, 3) +sysfs_uevent_get(const char *path, const char *fmt, ...) +{ + char filename[PATH_MAX + 1], *key, *line = NULL, *value = NULL; + size_t size = 0, len; + ssize_t num; + va_list ap; + FILE *fp; + + va_start(ap, fmt); + num = vasprintf(&key, fmt, ap); + va_end(ap); + len = num; + + snprintf(filename, sizeof(filename), "%s/uevent", path); + + fp = fopen(filename, "r"); + if (!fp) { + free(key); + return NULL; + } + + while ((num = getline(&line, &size, fp)) >= 0) { + if ((strncmp(line, key, len) == 0) && (line[len] == '=')) { + char *start = line + len + 1, *end = line + num - 1; + + if (*end != '\n') + end++; + + value = strndup(start, end - start); + break; + } + } + + free(line); + fclose(fp); + + free(key); + + return value; +} +#endif + static int drmParseSubsystemType(int maj, int min) { #ifdef __linux__ @@ -2906,6 +2950,9 @@ static int drmParseSubsystemType(int maj, int min) if (strncmp(name, "/pci", 4) == 0) return DRM_BUS_PCI; + if (strncmp(name, "/usb", 4) == 0) + return DRM_BUS_USB; + return -EINVAL; #elif defined(__OpenBSD__) return DRM_BUS_PCI; @@ -2992,6 +3039,10 @@ static int drmCompareBusInfo(drmDevicePtr a, drmDevicePtr b) switch (a->bustype) { case DRM_BUS_PCI: return memcmp(a->businfo.pci, b->businfo.pci, sizeof(drmPciBusInfo)); + + case DRM_BUS_USB: + return memcmp(a->businfo.usb, b->businfo.usb, sizeof(drmUsbBusInfo)); + default: break; } @@ -3235,6 +3286,113 @@ free_device: return ret; } +static int drmParseUsbBusInfo(int maj, int min, drmUsbBusInfoPtr info) +{ +#ifdef __linux__ + char path[PATH_MAX + 1], *value; + unsigned int bus, dev; + int ret; + + snprintf(path, sizeof(path), "/sys/dev/char/%d:%d/device", maj, min); + + value = sysfs_uevent_get(path, "BUSNUM"); + if (!value) + return -ENOENT; + + ret = sscanf(value, "%03u", &bus); + free(value); + + if (ret <= 0) + return -errno; + + value = sysfs_uevent_get(path, "DEVNUM"); + if (!value) + return -ENOENT; + + ret = sscanf(value, "%03u", &dev); + free(value); + + if (ret <= 0) + return -errno; + + info->bus = bus; + info->dev = dev; + + return 0; +#else +#warning "Missing implementation of drmParseUsbBusInfo" + return -EINVAL; +#endif +} + +static int drmParseUsbDeviceInfo(int maj, int min, drmUsbDeviceInfoPtr info) +{ +#ifdef __linux__ + char path[PATH_MAX + 1], *value; + unsigned int vendor, product; + int ret; + + snprintf(path, sizeof(path), "/sys/dev/char/%d:%d/device", maj, min); + + value = sysfs_uevent_get(path, "PRODUCT"); + if (!value) + return -ENOENT; + + ret = sscanf(value, "%x/%x", &vendor, &product); + free(value); + + if (ret <= 0) + return -errno; + + info->vendor = vendor; + info->product = product; + + return 0; +#else +#warning "Missing implementation of drmParseUsbDeviceInfo" + return -EINVAL; +#endif +} + +static int drmProcessUsbDevice(drmDevicePtr *device, const char *node, + int node_type, int maj, int min, + bool fetch_deviceinfo, uint32_t flags) +{ + drmDevicePtr dev; + char *ptr; + int ret; + + dev = drmDeviceAlloc(node_type, node, sizeof(drmUsbBusInfo), + sizeof(drmUsbDeviceInfo), &ptr); + if (!dev) + return -ENOMEM; + + dev->bustype = DRM_BUS_USB; + + dev->businfo.usb = (drmUsbBusInfoPtr)ptr; + + ret = drmParseUsbBusInfo(maj, min, dev->businfo.usb); + if (ret < 0) + goto free_device; + + if (fetch_deviceinfo) { + ptr += sizeof(drmUsbBusInfo); + dev->deviceinfo.usb = (drmUsbDeviceInfoPtr)ptr; + + ret = drmParseUsbDeviceInfo(maj, min, dev->deviceinfo.usb); + if (ret < 0) + goto free_device; + } + + *device = dev; + + return 0; + +free_device: + free(dev); + return ret; +} + /* Consider devices located on the same bus as duplicate and fold the respective * entries into a single one. * @@ -3410,6 +3568,14 @@ int drmGetDevice2(int fd, uint32_t flags, drmDevicePtr *device) continue; break; + + case DRM_BUS_USB: + ret = drmProcessUsbDevice(&d, node, node_type, maj, min, true, flags); + if (ret) + continue; + + break; + default: continue; } @@ -3541,6 +3707,15 @@ int drmGetDevices2(uint32_t flags, drmDevicePtr devices[], int max_devices) continue; break; + + case DRM_BUS_USB: + ret = drmProcessUsbDevice(&device, node, node_type, maj, min, + devices != NULL, flags); + if (ret) + goto free_devices; + + break; + default: continue; } diff --git a/xf86drm.h b/xf86drm.h index b340fc4..65d5321 100644 --- a/xf86drm.h +++ b/xf86drm.h @@ -767,6 +767,7 @@ extern char *drmGetPrimaryDeviceNameFromFd(int fd); extern char *drmGetRenderDeviceNameFromFd(int fd); #define DRM_BUS_PCI 0 +#define DRM_BUS_USB 1 typedef struct _drmPciBusInfo { uint16_t domain; @@ -783,15 +784,27 @@ typedef struct _drmPciDeviceInfo { uint8_t revision_id; } drmPciDeviceInfo, *drmPciDeviceInfoPtr; +typedef struct _drmUsbBusInfo { + uint8_t bus; + uint8_t dev; +} drmUsbBusInfo, *drmUsbBusInfoPtr; + +typedef struct _drmUsbDeviceInfo { + uint16_t vendor; + uint16_t product; +} drmUsbDeviceInfo, *drmUsbDeviceInfoPtr; + typedef struct _drmDevice { char **nodes; /* DRM_NODE_MAX sized array */ int available_nodes; /* DRM_NODE_* bitmask */ int bustype; union { drmPciBusInfoPtr pci; + drmUsbBusInfoPtr usb; } businfo; union { drmPciDeviceInfoPtr pci; + drmUsbDeviceInfoPtr usb; } deviceinfo; } drmDevice, *drmDevicePtr; -- 2.7.4