X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fparport%2Fprobe.c;h=ea83b70e0de2ccf5bf03b49ea27875a5b46e1a85;hb=7b6d18215c859b06815d28a2b0f517c9053d9ab1;hp=a360928bae0d969e5fa2579bf1ae8884604d26c6;hpb=daddc0d38b3571bed170afa273a49a0eba090c1e;p=linux-2.6.git diff --git a/drivers/parport/probe.c b/drivers/parport/probe.c index a360928ba..ea83b70e0 100644 --- a/drivers/parport/probe.c +++ b/drivers/parport/probe.c @@ -2,7 +2,7 @@ * Parallel port device probing code * * Authors: Carsten Gross, carsten@sol.wohnheim.uni-ulm.de - * Philip Blundell + * Philip Blundell */ #include @@ -11,9 +11,9 @@ #include #include -static struct { - char *token; - char *descr; +static const struct { + const char *token; + const char *descr; } classes[] = { { "", "Legacy device" }, { "PRINTER", "Printer" }, @@ -48,14 +48,6 @@ static void pretty_print(struct parport *port, int device) printk("\n"); } -static char *strdup(char *str) -{ - int n = strlen(str)+1; - char *s = kmalloc(n, GFP_KERNEL); - if (!s) return NULL; - return strcpy(s, str); -} - static void parse_data(struct parport *port, int device, char *str) { char *txt = kmalloc(strlen(str)+1, GFP_KERNEL); @@ -86,18 +78,16 @@ static void parse_data(struct parport *port, int device, char *str) u++; } if (!strcmp(p, "MFG") || !strcmp(p, "MANUFACTURER")) { - if (info->mfr) - kfree (info->mfr); - info->mfr = strdup(sep); + kfree(info->mfr); + info->mfr = kstrdup(sep, GFP_KERNEL); } else if (!strcmp(p, "MDL") || !strcmp(p, "MODEL")) { - if (info->model) - kfree (info->model); - info->model = strdup(sep); + kfree(info->model); + info->model = kstrdup(sep, GFP_KERNEL); } else if (!strcmp(p, "CLS") || !strcmp(p, "CLASS")) { int i; - if (info->class_name) - kfree (info->class_name); - info->class_name = strdup(sep); + + 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++) { @@ -110,21 +100,22 @@ static void parse_data(struct parport *port, int device, char *str) info->class = PARPORT_CLASS_OTHER; } else if (!strcmp(p, "CMD") || !strcmp(p, "COMMAND SET")) { - if (info->cmdset) - kfree (info->cmdset); - info->cmdset = strdup(sep); + 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")) { - if (info->description) - kfree (info->description); - info->description = strdup(sep); + kfree(info->description); + info->description = kstrdup(sep, GFP_KERNEL); } } rock_on: - if (q) p = q+1; else p=NULL; + if (q) + p = q + 1; + else + p = NULL; } /* If the device didn't tell us its class, maybe we have managed to @@ -137,8 +128,131 @@ static void parse_data(struct parport *port, int device, char *str) 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 lenghts 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 len) +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", @@ -148,69 +262,21 @@ ssize_t parport_device_id (int devnum, char *buffer, size_t len) parport_claim_or_block (dev); - /* Negotiate to compatibility mode, and then to device ID mode. - * (This is in case we are already in device ID mode.) */ + /* 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) { - int idlen; - unsigned char length[2]; - - /* First two bytes are MSB,LSB of inclusive length. */ - retval = parport_read (dev->port, length, 2); - - if (retval != 2) goto end_id; - - idlen = (length[0] << 8) + length[1] - 2; - if (idlen < len) - len = idlen; - retval = parport_read (dev->port, buffer, len); - - if (retval != len) - printk (KERN_DEBUG "%s: only read %Zd of %Zd ID bytes\n", - dev->port->name, retval, - len); - - /* Some printer manufacturers mistakenly believe that - the length field is supposed to be _exclusive_. - In addition, there are broken devices out there - that don't even finish off with a semi-colon. */ - if (buffer[len - 1] != ';') { - ssize_t diff; - diff = parport_read (dev->port, buffer + len, 2); - retval += diff; - - if (diff) - printk (KERN_DEBUG - "%s: device reported incorrect " - "length field (%d, should be %Zd)\n", - dev->port->name, idlen, retval); - else { - /* One semi-colon short of a device ID. */ - buffer[len++] = ';'; - printk (KERN_DEBUG "%s: faking semi-colon\n", - dev->port->name); - - /* If we get here, I don't think we - need to worry about the possible - standard violation of having read - more than we were told to. The - device is non-compliant anyhow. */ - } - } - - end_id: - buffer[len] = '\0'; + 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); - - if (retval > 2) - parse_data (dev->port, dev->daisy, buffer); + parport_release (dev); parport_close (dev); return retval; } -EXPORT_SYMBOL(parport_device_id);