/* * Parallel port device probing code * * Authors: Carsten Gross, carsten@sol.wohnheim.uni-ulm.de * Philip Blundell <philb@gnu.org> */ #include <linux/module.h> #include <linux/parport.h> #include <linux/ctype.h> #include <linux/string.h> #include <asm/uaccess.h> static const struct { const char *token; const char *descr; } classes[] = { { "", "Legacy device" }, { "PRINTER", "Printer" }, { "MODEM", "Modem" }, { "NET", "Network device" }, { "HDC", "Hard disk" }, { "PCMCIA", "PCMCIA" }, { "MEDIA", "Multimedia device" }, { "FDC", "Floppy disk" }, { "PORTS", "Ports" }, { "SCANNER", "Scanner" }, { "DIGICAM", "Digital camera" }, { "", "Unknown device" }, { "", "Unspecified" }, { "SCSIADAPTER", "SCSI adapter" }, { NULL, NULL } }; static void pretty_print(struct parport *port, int device) { struct parport_device_info *info = &port->probe_info[device + 1]; printk(KERN_INFO "%s", port->name); if (device >= 0) printk (" (addr %d)", device); printk (": %s", classes[info->class].descr); if (info->class) printk(", %s %s", info->mfr, info->model); printk("\n"); } static void parse_data(struct parport *port, int device, char *str) { char *txt = kmalloc(strlen(str)+1, GFP_KERNEL); char *p = txt, *q; int guessed_class = PARPORT_CLASS_UNSPEC; struct parport_device_info *info = &port->probe_info[device + 1]; if (!txt) { printk(KERN_WARNING "%s probe: memory squeeze\n", port->name); return; } strcpy(txt, str); while (p) { char *sep; q = strchr(p, ';'); if (q) *q = 0; sep = strchr(p, ':'); if (sep) { char *u; *(sep++) = 0; /* Get rid of trailing blanks */ u = sep + strlen (sep) - 1; while (u >= p && *u == ' ') *u-- = '\0'; u = p; while (*u) { *u = toupper(*u); u++; } if (!strcmp(p, "MFG") || !strcmp(p, "MANUFACTURER")) { kfree(info->mfr); info->mfr = kstrdup(sep, GFP_KERNEL); } else if (!strcmp(p, "MDL") || !strcmp(p, "MODEL")) { kfree(info->model); info->model = kstrdup(sep, GFP_KERNEL); } else if (!strcmp(p, "CLS") || !strcmp(p, "CLASS")) { int i; kfree(info->class_name); info->class_name = kstrdup(sep, GFP_KERNEL); for (u = sep; *u; u++) *u = toupper(*u); for (i = 0; classes[i].token; i++) { if (!strcmp(classes[i].token, sep)) { info->class = i; goto rock_on; } } printk(KERN_WARNING "%s probe: warning, class '%s' not understood.\n", port->name, sep); info->class = PARPORT_CLASS_OTHER; } else if (!strcmp(p, "CMD") || !strcmp(p, "COMMAND SET")) { kfree(info->cmdset); info->cmdset = kstrdup(sep, GFP_KERNEL); /* if it speaks printer language, it's probably a printer */ if (strstr(sep, "PJL") || strstr(sep, "PCL")) guessed_class = PARPORT_CLASS_PRINTER; } else if (!strcmp(p, "DES") || !strcmp(p, "DESCRIPTION")) { kfree(info->description); info->description = kstrdup(sep, GFP_KERNEL); } } rock_on: if (q) p = q + 1; else p = NULL; } /* If the device didn't tell us its class, maybe we have managed to guess one from the things it did say. */ if (info->class == PARPORT_CLASS_UNSPEC) info->class = guessed_class; pretty_print (port, device); kfree(txt); } /* Read up to count-1 bytes of device id. Terminate buffer with * '\0'. Buffer begins with two Device ID length bytes as given by * device. */ static ssize_t parport_read_device_id (struct parport *port, char *buffer, size_t count) { unsigned char length[2]; unsigned lelen, belen; size_t idlens[4]; unsigned numidlens; unsigned current_idlen; ssize_t retval; size_t len; /* First two bytes are MSB,LSB of inclusive length. */ retval = parport_read (port, length, 2); if (retval < 0) return retval; if (retval != 2) return -EIO; if (count < 2) return 0; memcpy(buffer, length, 2); len = 2; /* Some devices wrongly send LE length, and some send it two * bytes short. Construct a sorted array of lengths to try. */ belen = (length[0] << 8) + length[1]; lelen = (length[1] << 8) + length[0]; idlens[0] = min(belen, lelen); idlens[1] = idlens[0]+2; if (belen != lelen) { int off = 2; /* Don't try lengths of 0x100 and 0x200 as 1 and 2 */ if (idlens[0] <= 2) off = 0; idlens[off] = max(belen, lelen); idlens[off+1] = idlens[off]+2; numidlens = off+2; } else { /* Some devices don't truly implement Device ID, but * just return constant nibble forever. This catches * also those cases. */ if (idlens[0] == 0 || idlens[0] > 0xFFF) { printk (KERN_DEBUG "%s: reported broken Device ID" " length of %#zX bytes\n", port->name, idlens[0]); return -EIO; } numidlens = 2; } /* Try to respect the given ID length despite all the bugs in * the ID length. Read according to shortest possible ID * first. */ for (current_idlen = 0; current_idlen < numidlens; ++current_idlen) { size_t idlen = idlens[current_idlen]; if (idlen+1 >= count) break; retval = parport_read (port, buffer+len, idlen-len); if (retval < 0) return retval; len += retval; if (port->physport->ieee1284.phase != IEEE1284_PH_HBUSY_DAVAIL) { if (belen != len) { printk (KERN_DEBUG "%s: Device ID was %zd bytes" " while device told it would be %d" " bytes\n", port->name, len, belen); } goto done; } /* This might end reading the Device ID too * soon. Hopefully the needed fields were already in * the first 256 bytes or so that we must have read so * far. */ if (buffer[len-1] == ';') { printk (KERN_DEBUG "%s: Device ID reading stopped" " before device told data not available. " "Current idlen %u of %u, len bytes %02X %02X\n", port->name, current_idlen, numidlens, length[0], length[1]); goto done; } } if (current_idlen < numidlens) { /* Buffer not large enough, read to end of buffer. */ size_t idlen, len2; if (len+1 < count) { retval = parport_read (port, buffer+len, count-len-1); if (retval < 0) return retval; len += retval; } /* Read the whole ID since some devices would not * otherwise give back the Device ID from beginning * next time when asked. */ idlen = idlens[current_idlen]; len2 = len; while(len2 < idlen && retval > 0) { char tmp[4]; retval = parport_read (port, tmp, min(sizeof tmp, idlen-len2)); if (retval < 0) return retval; len2 += retval; } } /* In addition, there are broken devices out there that don't even finish off with a semi-colon. We do not need to care about those at this time. */ done: buffer[len] = '\0'; return len; } /* Get Std 1284 Device ID. */ ssize_t parport_device_id (int devnum, char *buffer, size_t count) { ssize_t retval = -ENXIO; struct pardevice *dev = parport_open (devnum, "Device ID probe"); if (!dev) return -ENXIO; parport_claim_or_block (dev); /* Negotiate to compatibility mode, and then to device ID * mode. (This so that we start form beginning of device ID if * already in device ID mode.) */ parport_negotiate (dev->port, IEEE1284_MODE_COMPAT); retval = parport_negotiate (dev->port, IEEE1284_MODE_NIBBLE | IEEE1284_DEVICEID); if (!retval) { retval = parport_read_device_id (dev->port, buffer, count); parport_negotiate (dev->port, IEEE1284_MODE_COMPAT); if (retval > 2) parse_data (dev->port, dev->daisy, buffer+2); } parport_release (dev); parport_close (dev); return retval; }