The following commit has been merged in the linux branch: commit eaf76e0d027a917a013ad8a88a94132d0feab622 Author: Stefan Richter stefanr@s5r6.in-berlin.de Date: Thu Oct 8 00:39:31 2009 +0200
firewire: sbp2: provide fallback if mgt_ORB_timeout is missing
The Unit_Characteristics entry of an SBP-2 unit directory is not mandatory as far as I can tell. If it is missing, we would probably fail to log in into the target because firewire-sbp2 would not wait for status after it sent the login request.
The fix moves the cleanup of tgt->mgt_orb_timeout into a place where it is executed exactly once before login, rather than 0..n times depending on the target's config ROM. With targets with one or more Unit_Characteristics entries, the result is the same as before.
Signed-off-by: Stefan Richter stefanr@s5r6.in-berlin.de
diff --git a/drivers/firewire/sbp2.c b/drivers/firewire/sbp2.c index 50f0176..98dbbda 100644 --- a/drivers/firewire/sbp2.c +++ b/drivers/firewire/sbp2.c @@ -188,14 +188,7 @@ static struct fw_device *target_device(struct sbp2_target *tgt) /* Impossible login_id, to detect logout attempt before successful login */ #define INVALID_LOGIN_ID 0x10000
-/* - * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be - * provided in the config rom. Most devices do provide a value, which - * we'll use for login management orbs, but with some sane limits. - */ -#define SBP2_MIN_LOGIN_ORB_TIMEOUT 5000U /* Timeout in ms */ -#define SBP2_MAX_LOGIN_ORB_TIMEOUT 40000U /* Timeout in ms */ -#define SBP2_ORB_TIMEOUT 2000U /* Timeout in ms */ +#define SBP2_ORB_TIMEOUT 2000U /* Timeout in ms */ #define SBP2_ORB_NULL 0x80000000 #define SBP2_RETRY_LIMIT 0xf /* 15 retries */ #define SBP2_CYCLE_LIMIT (0xc8 << 12) /* 200 125us cycles */ @@ -1034,7 +1027,6 @@ static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory, { struct fw_csr_iterator ci; int key, value; - unsigned int timeout;
fw_csr_iterator_init(&ci, directory); while (fw_csr_iterator_next(&ci, &key, &value)) { @@ -1059,17 +1051,7 @@ static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory,
case SBP2_CSR_UNIT_CHARACTERISTICS: /* the timeout value is stored in 500ms units */ - timeout = ((unsigned int) value >> 8 & 0xff) * 500; - timeout = max(timeout, SBP2_MIN_LOGIN_ORB_TIMEOUT); - tgt->mgt_orb_timeout = - min(timeout, SBP2_MAX_LOGIN_ORB_TIMEOUT); - - if (timeout > tgt->mgt_orb_timeout) - fw_notify("%s: config rom contains %ds " - "management ORB timeout, limiting " - "to %ds\n", tgt->bus_id, - timeout / 1000, - tgt->mgt_orb_timeout / 1000); + tgt->mgt_orb_timeout = (value >> 8 & 0xff) * 500; break;
case SBP2_CSR_LOGICAL_UNIT_NUMBER: @@ -1087,6 +1069,22 @@ static int sbp2_scan_unit_dir(struct sbp2_target *tgt, u32 *directory, return 0; }
+/* + * Per section 7.4.8 of the SBP-2 spec, a mgt_ORB_timeout value can be + * provided in the config rom. Most devices do provide a value, which + * we'll use for login management orbs, but with some sane limits. + */ +static void sbp2_clamp_management_orb_timeout(struct sbp2_target *tgt) +{ + unsigned int timeout = tgt->mgt_orb_timeout; + + if (timeout > 40000) + fw_notify("%s: %ds mgt_ORB_timeout limited to 40s\n", + tgt->bus_id, timeout / 1000); + + tgt->mgt_orb_timeout = clamp_val(timeout, 5000, 40000); +} + static void sbp2_init_workarounds(struct sbp2_target *tgt, u32 model, u32 firmware_revision) { @@ -1171,6 +1169,7 @@ static int sbp2_probe(struct device *dev) &firmware_revision) < 0) goto fail_tgt_put;
+ sbp2_clamp_management_orb_timeout(tgt); sbp2_init_workarounds(tgt, model, firmware_revision);
/*