[PATCH] ub: fix for blank CDs

This patch fixes a microcode lockup in my CD-ROM adapters when a blank CD is inserted. However, do not try to burn CDs yet! I'm pretty sure that trying it will end in coasters. - Fix a few cases where we were unable to resynchronize with replies for previous commands. The main thing is to keep reading replies in case of a stall. This is done with the new state CLRRS. - Since I am forgetting the basic state machine already, document it. - Move counter increments in the looping path in its own function. - Fix a harmless buglet in case CSW read fails to submit: do not override state. - Implement the Alan Stern's idea for adaptive signature checking. Signed-off-by: Pete Zaitcev <zaitcev@yahoo.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
author: Pete Zaitcev <zaitcev@redhat.com> 2005-07-27 14:43:51 -0400
committer: Linus Torvalds <torvalds@g5.osdl.org> 2005-07-27 19:25:52 -0400
commit: 1872bcebbcd6ad7ddd99e92fb1e4f3d19e73919c (patch)
tree: dc1fe75f915fb58edb36b0bab877b2787e663b92
parent: 90c5029e471636f21221bf66b9a46ada2ab79a22 (diff)
1 files changed, 170 insertions, 41 deletions
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index 685f061e69b2..a026567f5d18 100644
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -23,6 +23,7 @@
 *  -- Exterminate P3 printks
 *  -- Resove XXX's
 *  -- Redo "benh's retries", perhaps have spin-up code to handle them. V:D=?
+ *  -- CLEAR, CLR2STS, CLRRS seem to be ripe for refactoring.
 */
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -38,6 +39,73 @@
 #define UB_MAJOR 180
 /*
+ * The command state machine is the key model for understanding of this driver.
+ *
+ * The general rule is that all transitions are done towards the bottom
+ * of the diagram, thus preventing any loops.
+ *
+ * An exception to that is how the STAT state is handled. A counter allows it
+ * to be re-entered along the path marked with [C].
+ *
+ *       +--------+
+ *       ! INIT   !
+ *       +--------+
+ *           !
+ *        ub_scsi_cmd_start fails ->--------------------------------------\
+ *           !                                                            !
+ *           V                                                            !
+ *       +--------+                                                       !
+ *       ! CMD    !                                                       !
+ *       +--------+                                                       !
+ *           !                                            +--------+      !
+ *         was -EPIPE -->-------------------------------->! CLEAR  !      !
+ *           !                                            +--------+      !
+ *           !                                                !           !
+ *         was error -->------------------------------------- ! --------->\
+ *           !                                                !           !
+ *  /--<-- cmd->dir == NONE ?                                 !           !
+ *  !        !                                                !           !
+ *  !        V                                                !           !
+ *  !    +--------+                                           !           !
+ *  !    ! DATA   !                                           !           !
+ *  !    +--------+                                           !           !
+ *  !        !                           +---------+          !           !
+ *  !      was -EPIPE -->--------------->! CLR2STS !          !           !
+ *  !        !                           +---------+          !           !
+ *  !        !                                !               !           !
+ *  !        !                              was error -->---- ! --------->\
+ *  !      was error -->--------------------- ! ------------- ! --------->\
+ *  !        !                                !               !           !
+ *  !        V                                !               !           !
+ *  \--->+--------+                           !               !           !
+ *       ! STAT   !<--------------------------/               !           !
+ *  /--->+--------+                                           !           !
+ *  !        !                                                !           !
+ * [C]     was -EPIPE -->-----------\                         !           !
+ *  !        !                      !                         !           !
+ *  +<---- len == 0                 !                         !           !
+ *  !        !                      !                         !           !
+ *  !      was error -->--------------------------------------!---------->\
+ *  !        !                      !                         !           !
+ *  +<---- bad CSW                  !                         !           !
+ *  +<---- bad tag                  !                         !           !
+ *  !        !                      V                         !           !
+ *  !        !                 +--------+                     !           !
+ *  !        !                 ! CLRRS  !                     !           !
+ *  !        !                 +--------+                     !           !
+ *  !        !                      !                         !           !
+ *  \------- ! --------------------[C]--------\               !           !
+ *           !                                !               !           !
+ *         cmd->error---\                +--------+           !           !
+ *           !          +--------------->! SENSE  !<----------/           !
+ *         STAT_FAIL----/                +--------+                       !
+ *           !                                !                           V
+ *           !                                V                      +--------+
+ *           \--------------------------------\--------------------->! DONE   !
+ *                                                                   +--------+
+ */
+/*
 * Definitions which have to be scattered once we understand the layout better.
 */
@@ -91,8 +159,6 @@ struct bulk_cs_wrap {
 #define US_BULK_CS_WRAP_LEN     13
 #define US_BULK_CS_SIGN         0x53425355      /* spells out 'USBS' */
-/* This is for Olympus Camedia digital cameras */
-#define US_BULK_CS_OLYMPUS_SIGN 0x55425355      /* spells out 'USBU' */
 #define US_BULK_STAT_OK         0
 #define US_BULK_STAT_FAIL       1
 #define US_BULK_STAT_PHASE      2
@@ -135,6 +201,7 @@ enum ub_scsi_cmd_state {
        UB_CMDST_CLR2STS,               /* Clearing before requesting status */
        UB_CMDST_STAT,                  /* Status phase */
        UB_CMDST_CLEAR,                 /* Clearing a stall (halt, actually) */
+        UB_CMDST_CLRRS,                 /* Clearing before retrying status */
        UB_CMDST_SENSE,                 /* Sending Request Sense */
        UB_CMDST_DONE                   /* Final state */
 };
@@ -146,6 +213,7 @@ static char *ub_scsi_cmd_stname[] = {
        "c2s",
        "sts",
        "clr",
+        "crs",
        "Sen",
        "fin"
 };
@@ -316,6 +384,7 @@ struct ub_dev {
        struct urb work_urb;
        struct timer_list work_timer;
        int last_pipe;                  /* What might need clearing */
+        __le32 signature;               /* Learned signature */
        struct bulk_cb_wrap work_bcb;
        struct bulk_cs_wrap work_bcs;
        struct usb_ctrlrequest work_cr;
@@ -339,8 +408,9 @@ static void ub_scsi_action(unsigned long _dev);
 static void ub_scsi_dispatch(struct ub_dev *sc);
 static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
 static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc);
-static void __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
+static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
 static int ub_submit_clear_stall(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
    int stalled_pipe);
@@ -1085,6 +1155,28 @@ static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                ub_state_stat(sc, cmd);
+        } else if (cmd->state == UB_CMDST_CLRRS) {
+                if (urb->status == -EPIPE) {
+                        /*
+                         * STALL while clearning STALL.
+                         * The control pipe clears itself - nothing to do.
+                         * XXX Might try to reset the device here and retry.
+                         */
+                        printk(KERN_NOTICE "%s: stall on control pipe\n",
+                            sc->name);
+                        goto Bad_End;
+                }
+                /*
+                 * We ignore the result for the halt clear.
+                 */
+                /* reset the endpoint toggle */
+                usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
+                        usb_pipeout(sc->last_pipe), 0);
+                ub_state_stat_counted(sc, cmd);
        } else if (cmd->state == UB_CMDST_CMD) {
                if (urb->status == -EPIPE) {
                        rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
@@ -1190,52 +1282,57 @@ static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                                 */
                                goto Bad_End;
                        }
-                        cmd->state = UB_CMDST_CLEAR;
+                        /*
+                         * Having a stall when getting CSW is an error, so
+                         * make sure uppper levels are not oblivious to it.
+                         */
+                        cmd->error = -EIO;              /* A cheap trick... */
+                        cmd->state = UB_CMDST_CLRRS;
                        ub_cmdtr_state(sc, cmd);
                        return;
                }
+                if (urb->status == -EOVERFLOW) {
+                        /*
+                         * XXX We are screwed here. Retrying is pointless,
+                         * because the pipelined data will not get in until
+                         * we read with a big enough buffer. We must reset XXX.
+                         */
+                        goto Bad_End;
+                }
                if (urb->status != 0)
                        goto Bad_End;
                if (urb->actual_length == 0) {
-                        /*
+                        ub_state_stat_counted(sc, cmd);
-                         * Some broken devices add unnecessary zero-length
-                         * packets to the end of their data transfers.
-                         * Such packets show up as 0-length CSWs. If we
-                         * encounter such a thing, try to read the CSW again.
-                         */
-                        if (++cmd->stat_count >= 4) {
-                                printk(KERN_NOTICE "%s: unable to get CSW\n",
-                                    sc->name);
-                                goto Bad_End;
-                        }
-                        __ub_state_stat(sc, cmd);
                        return;
                }
                /*
                 * Check the returned Bulk protocol status.
+                 * The status block has to be validated first.
                 */
                bcs = &sc->work_bcs;
-                rc = le32_to_cpu(bcs->Residue);
-                if (rc != cmd->len - cmd->act_len) {
+                if (sc->signature == cpu_to_le32(0)) {
                        /*
-                         * It is all right to transfer less, the caller has
+                         * This is the first reply, so do not perform the check.
-                         * to check. But it's not all right if the device
+                         * Instead, remember the signature the device uses
-                         * counts disagree with our counts.
+                         * for future checks. But do not allow a nul.
                         */
-                        /* P3 */ printk("%s: resid %d len %d act %d\n",
+                        sc->signature = bcs->Signature;
-                            sc->name, rc, cmd->len, cmd->act_len);
+                        if (sc->signature == cpu_to_le32(0)) {
-                        goto Bad_End;
+                                ub_state_stat_counted(sc, cmd);
-                }
+                                return;
+                        }
-#if 0
+                } else {
-                if (bcs->Signature != cpu_to_le32(US_BULK_CS_SIGN) &&
+                        if (bcs->Signature != sc->signature) {
-                    bcs->Signature != cpu_to_le32(US_BULK_CS_OLYMPUS_SIGN)) {
+                                ub_state_stat_counted(sc, cmd);
-                        /* Windows ignores signatures, so do we. */
+                                return;
+                        }
                }
-#endif
                if (bcs->Tag != cmd->tag) {
                        /*
@@ -1245,16 +1342,22 @@ static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                         * commands and reply at commands we timed out before.
                         * Without flushing these replies we loop forever.
                         */
-                        if (++cmd->stat_count >= 4) {
+                        ub_state_stat_counted(sc, cmd);
-                                printk(KERN_NOTICE "%s: "
-                                    "tag mismatch orig 0x%x reply 0x%x\n",
-                                    sc->name, cmd->tag, bcs->Tag);
-                                goto Bad_End;
-                        }
-                        __ub_state_stat(sc, cmd);
                        return;
                }
+                rc = le32_to_cpu(bcs->Residue);
+                if (rc != cmd->len - cmd->act_len) {
+                        /*
+                         * It is all right to transfer less, the caller has
+                         * to check. But it's not all right if the device
+                         * counts disagree with our counts.
+                         */
+                        /* P3 */ printk("%s: resid %d len %d act %d\n",
+                            sc->name, rc, cmd->len, cmd->act_len);
+                        goto Bad_End;
+                }
                switch (bcs->Status) {
                case US_BULK_STAT_OK:
                        break;
@@ -1272,6 +1375,10 @@ static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                }
                /* Not zeroing error to preserve a babble indicator */
+                if (cmd->error != 0) {
+                        ub_state_sense(sc, cmd);
+                        return;
+                }
                cmd->state = UB_CMDST_DONE;
                ub_cmdtr_state(sc, cmd);
                ub_cmdq_pop(sc);
@@ -1310,7 +1417,7 @@ static void ub_state_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd, int rc)
 * Factorization helper for the command state machine:
 * Submit a CSW read.
 */
-static void __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+static int __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 {
        int rc;
@@ -1328,11 +1435,12 @@ static void __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                /* XXX Clear stalls */
                ub_complete(&sc->work_done);
                ub_state_done(sc, cmd, rc);
-                return;
+                return -1;
        }
        sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
        add_timer(&sc->work_timer);
+        return 0;
 }
 /*
@@ -1341,7 +1449,9 @@ static void __ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 */
 static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 {
-        __ub_state_stat(sc, cmd);
+        if (__ub_state_stat(sc, cmd) != 0)
+                return;
        cmd->stat_count = 0;
        cmd->state = UB_CMDST_STAT;
@@ -1350,6 +1460,25 @@ static void ub_state_stat(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 /*
 * Factorization helper for the command state machine:
+ * Submit a CSW read and go to STAT state with counter (along [C] path).
+ */
+static void ub_state_stat_counted(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
+{
+        if (++cmd->stat_count >= 4) {
+                ub_state_sense(sc, cmd);
+                return;
+        }
+        if (__ub_state_stat(sc, cmd) != 0)
+                return;
+        cmd->state = UB_CMDST_STAT;
+        ub_cmdtr_state(sc, cmd);
+}
+/*
+ * Factorization helper for the command state machine:
 * Submit a REQUEST SENSE and go to SENSE state.
 */
 static void ub_state_sense(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
author	Pete Zaitcev <zaitcev@redhat.com>	2005-07-27 14:43:51 -0400
committer	Linus Torvalds <torvalds@g5.osdl.org>	2005-07-27 19:25:52 -0400
commit	1872bcebbcd6ad7ddd99e92fb1e4f3d19e73919c (patch)
tree	dc1fe75f915fb58edb36b0bab877b2787e663b92
parent	90c5029e471636f21221bf66b9a46ada2ab79a22 (diff)

diff --git a/drivers/block/ub.c b/drivers/block/ub.c index 685f061e69b2..a026567f5d18 100644 --- a/drivers/block/ub.c +++ b/drivers/block/ub.c
@@ -23,6 +23,7 @@
23	* -- Exterminate P3 printks	23	* -- Exterminate P3 printks
24	* -- Resove XXX's	24	* -- Resove XXX's
25	* -- Redo "benh's retries", perhaps have spin-up code to handle them. V:D=?	25	* -- Redo "benh's retries", perhaps have spin-up code to handle them. V:D=?
		26	* -- CLEAR, CLR2STS, CLRRS seem to be ripe for refactoring.
26	*/	27	*/
27	#include <linux/kernel.h>	28	#include <linux/kernel.h>
28	#include <linux/module.h>	29	#include <linux/module.h>
@@ -38,6 +39,73 @@
38	#define UB_MAJOR 180	39	#define UB_MAJOR 180
39		40
40	/*	41	/*
		42	* The command state machine is the key model for understanding of this driver.
		43	*
		44	* The general rule is that all transitions are done towards the bottom
		45	* of the diagram, thus preventing any loops.
		46	*
		47	* An exception to that is how the STAT state is handled. A counter allows it
		48	* to be re-entered along the path marked with [C].
		49	*
		50	* +--------+
		51	* ! INIT !
		52	* +--------+
		53	* !
		54	* ub_scsi_cmd_start fails ->--------------------------------------\
		55	* ! !
		56	* V !
		57	* +--------+ !
		58	* ! CMD ! !
		59	* +--------+ !
		60	* ! +--------+ !
		61	* was -EPIPE -->-------------------------------->! CLEAR ! !
		62	* ! +--------+ !
		63	* ! ! !
		64	* was error -->------------------------------------- ! --------->\
		65	* ! ! !
		66	* /--<-- cmd->dir == NONE ? ! !
		67	* ! ! ! !
		68	* ! V ! !
		69	* ! +--------+ ! !
		70	* ! ! DATA ! ! !
		71	* ! +--------+ ! !
		72	* ! ! +---------+ ! !
		73	* ! was -EPIPE -->--------------->! CLR2STS ! ! !
		74	* ! ! +---------+ ! !
		75	* ! ! ! ! !
		76	* ! ! was error -->---- ! --------->\
		77	* ! was error -->--------------------- ! ------------- ! --------->\
		78	* ! ! ! ! !
		79	* ! V ! ! !
		80	* \--->+--------+ ! ! !
		81	* ! STAT !<--------------------------/ ! !
		82	* /--->+--------+ ! !
		83	* ! ! ! !
		84	* [C] was -EPIPE -->-----------\ ! !
		85	* ! ! ! ! !
		86	* +<---- len == 0 ! ! !
		87	* ! ! ! ! !
		88	* ! was error -->--------------------------------------!---------->\
		89	* ! ! ! ! !
		90	* +<---- bad CSW ! ! !
		91	* +<---- bad tag ! ! !
		92	* ! ! V ! !
		93	* ! ! +--------+ ! !
		94	* ! ! ! CLRRS ! ! !
		95	* ! ! +--------+ ! !
		96	* ! ! ! ! !
		97	* \------- ! --------------------[C]--------\ ! !
		98	* ! ! ! !
		99	* cmd->error---\ +--------+ ! !
		100	* ! +--------------->! SENSE !<----------/ !
		101	* STAT_FAIL----/ +--------+ !
		102	* ! ! V
		103	* ! V +--------+
		104	* \--------------------------------\--------------------->! DONE !
		105	* +--------+
		106	*/
		107
		108	/*
41	* Definitions which have to be scattered once we understand the layout better.	109	* Definitions which have to be scattered once we understand the layout better.
42	*/	110	*/
43		111
@@ -91,8 +159,6 @@ struct bulk_cs_wrap {
91		159
92	#define US_BULK_CS_WRAP_LEN 13	160	#define US_BULK_CS_WRAP_LEN 13
93	#define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */	161	#define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */
94	/* This is for Olympus Camedia digital cameras */
95	#define US_BULK_CS_OLYMPUS_SIGN 0x55425355 /* spells out 'USBU' */
96	#define US_BULK_STAT_OK 0	162	#define US_BULK_STAT_OK 0
97	#define US_BULK_STAT_FAIL 1	163	#define US_BULK_STAT_FAIL 1
98	#define US_BULK_STAT_PHASE 2	164	#define US_BULK_STAT_PHASE 2
@@ -135,6 +201,7 @@ enum ub_scsi_cmd_state {
135	UB_CMDST_CLR2STS, /* Clearing before requesting status */	201	UB_CMDST_CLR2STS, /* Clearing before requesting status */
136	UB_CMDST_STAT, /* Status phase */	202	UB_CMDST_STAT, /* Status phase */
137	UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */	203	UB_CMDST_CLEAR, /* Clearing a stall (halt, actually) */
		204	UB_CMDST_CLRRS, /* Clearing before retrying status */
138	UB_CMDST_SENSE, /* Sending Request Sense */	205	UB_CMDST_SENSE, /* Sending Request Sense */
139	UB_CMDST_DONE /* Final state */	206	UB_CMDST_DONE /* Final state */
140	};	207	};
@@ -146,6 +213,7 @@ static char *ub_scsi_cmd_stname[] = {
146	"c2s",	213	"c2s",
147	"sts",	214	"sts",
148	"clr",	215	"clr",
		216	"crs",
149	"Sen",	217	"Sen",
150	"fin"	218	"fin"
151	};	219	};
@@ -316,6 +384,7 @@ struct ub_dev {
316	struct urb work_urb;	384	struct urb work_urb;
317	struct timer_list work_timer;	385	struct timer_list work_timer;
318	int last_pipe; /* What might need clearing */	386	int last_pipe; /* What might need clearing */
		387	__le32 signature; /* Learned signature */
319	struct bulk_cb_wrap work_bcb;	388	struct bulk_cb_wrap work_bcb;
320	struct bulk_cs_wrap work_bcs;	389	struct bulk_cs_wrap work_bcs;
321	struct usb_ctrlrequest work_cr;	390	struct usb_ctrlrequest work_cr;
@@ -339,8 +408,9 @@ static void ub_scsi_action(unsigned long _dev);
339	static void ub_scsi_dispatch(struct ub_dev *sc);	408	static void ub_scsi_dispatch(struct ub_dev *sc);
340	static void ub_scsi_urb_compl(struct ub_dev sc, struct ub_scsi_cmd cmd);	409	static void ub_scsi_urb_compl(struct ub_dev sc, struct ub_scsi_cmd cmd);
341	static void ub_state_done(struct ub_dev sc, struct ub_scsi_cmd cmd, int rc);	410	static void ub_state_done(struct ub_dev sc, struct ub_scsi_cmd cmd, int rc);
342	static void __ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd);	411	static int __ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd);
343	static void ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd);	412	static void ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd);
		413	static void ub_state_stat_counted(struct ub_dev sc, struct ub_scsi_cmd cmd);
344	static void ub_state_sense(struct ub_dev sc, struct ub_scsi_cmd cmd);	414	static void ub_state_sense(struct ub_dev sc, struct ub_scsi_cmd cmd);
345	static int ub_submit_clear_stall(struct ub_dev sc, struct ub_scsi_cmd cmd,	415	static int ub_submit_clear_stall(struct ub_dev sc, struct ub_scsi_cmd cmd,
346	int stalled_pipe);	416	int stalled_pipe);
@@ -1085,6 +1155,28 @@ static void ub_scsi_urb_compl(struct ub_dev sc, struct ub_scsi_cmd cmd)
1085		1155
1086	ub_state_stat(sc, cmd);	1156	ub_state_stat(sc, cmd);
1087		1157
		1158	} else if (cmd->state == UB_CMDST_CLRRS) {
		1159	if (urb->status == -EPIPE) {
		1160	/*
		1161	* STALL while clearning STALL.
		1162	* The control pipe clears itself - nothing to do.
		1163	* XXX Might try to reset the device here and retry.
		1164	*/
		1165	printk(KERN_NOTICE "%s: stall on control pipe\n",
		1166	sc->name);
		1167	goto Bad_End;
		1168	}
		1169
		1170	/*
		1171	* We ignore the result for the halt clear.
		1172	*/
		1173
		1174	/* reset the endpoint toggle */
		1175	usb_settoggle(sc->dev, usb_pipeendpoint(sc->last_pipe),
		1176	usb_pipeout(sc->last_pipe), 0);
		1177
		1178	ub_state_stat_counted(sc, cmd);
		1179
1088	} else if (cmd->state == UB_CMDST_CMD) {	1180	} else if (cmd->state == UB_CMDST_CMD) {
1089	if (urb->status == -EPIPE) {	1181	if (urb->status == -EPIPE) {
1090	rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);	1182	rc = ub_submit_clear_stall(sc, cmd, sc->last_pipe);
@@ -1190,52 +1282,57 @@ static void ub_scsi_urb_compl(struct ub_dev sc, struct ub_scsi_cmd cmd)
1190	*/	1282	*/
1191	goto Bad_End;	1283	goto Bad_End;
1192	}	1284	}
1193	cmd->state = UB_CMDST_CLEAR;	1285
		1286	/*
		1287	* Having a stall when getting CSW is an error, so
		1288	* make sure uppper levels are not oblivious to it.
		1289	*/
		1290	cmd->error = -EIO; /* A cheap trick... */
		1291
		1292	cmd->state = UB_CMDST_CLRRS;
1194	ub_cmdtr_state(sc, cmd);	1293	ub_cmdtr_state(sc, cmd);
1195	return;	1294	return;
1196	}	1295	}
		1296	if (urb->status == -EOVERFLOW) {
		1297	/*
		1298	* XXX We are screwed here. Retrying is pointless,
		1299	* because the pipelined data will not get in until
		1300	* we read with a big enough buffer. We must reset XXX.
		1301	*/
		1302	goto Bad_End;
		1303	}
1197	if (urb->status != 0)	1304	if (urb->status != 0)
1198	goto Bad_End;	1305	goto Bad_End;
1199		1306
1200	if (urb->actual_length == 0) {	1307	if (urb->actual_length == 0) {
1201	/*	1308	ub_state_stat_counted(sc, cmd);
1202	* Some broken devices add unnecessary zero-length
1203	* packets to the end of their data transfers.
1204	* Such packets show up as 0-length CSWs. If we
1205	* encounter such a thing, try to read the CSW again.
1206	*/
1207	if (++cmd->stat_count >= 4) {
1208	printk(KERN_NOTICE "%s: unable to get CSW\n",
1209	sc->name);
1210	goto Bad_End;
1211	}
1212	__ub_state_stat(sc, cmd);
1213	return;	1309	return;
1214	}	1310	}
1215		1311
1216	/*	1312	/*
1217	* Check the returned Bulk protocol status.	1313	* Check the returned Bulk protocol status.
		1314	* The status block has to be validated first.
1218	*/	1315	*/
1219		1316
1220	bcs = &sc->work_bcs;	1317	bcs = &sc->work_bcs;
1221	rc = le32_to_cpu(bcs->Residue);	1318
1222	if (rc != cmd->len - cmd->act_len) {	1319	if (sc->signature == cpu_to_le32(0)) {
1223	/*	1320	/*
1224	* It is all right to transfer less, the caller has	1321	* This is the first reply, so do not perform the check.
1225	* to check. But it's not all right if the device	1322	* Instead, remember the signature the device uses
1226	* counts disagree with our counts.	1323	* for future checks. But do not allow a nul.
1227	*/	1324	*/
1228	/* P3 */ printk("%s: resid %d len %d act %d\n",	1325	sc->signature = bcs->Signature;
1229	sc->name, rc, cmd->len, cmd->act_len);	1326	if (sc->signature == cpu_to_le32(0)) {
1230	goto Bad_End;	1327	ub_state_stat_counted(sc, cmd);
1231	}	1328	return;
1232		1329	}
1233	#if 0	1330	} else {
1234	if (bcs->Signature != cpu_to_le32(US_BULK_CS_SIGN) &&	1331	if (bcs->Signature != sc->signature) {
1235	bcs->Signature != cpu_to_le32(US_BULK_CS_OLYMPUS_SIGN)) {	1332	ub_state_stat_counted(sc, cmd);
1236	/* Windows ignores signatures, so do we. */	1333	return;
		1334	}
1237	}	1335	}
1238	#endif
1239		1336
1240	if (bcs->Tag != cmd->tag) {	1337	if (bcs->Tag != cmd->tag) {
1241	/*	1338	/*
@@ -1245,16 +1342,22 @@ static void ub_scsi_urb_compl(struct ub_dev sc, struct ub_scsi_cmd cmd)
1245	* commands and reply at commands we timed out before.	1342	* commands and reply at commands we timed out before.
1246	* Without flushing these replies we loop forever.	1343	* Without flushing these replies we loop forever.
1247	*/	1344	*/
1248	if (++cmd->stat_count >= 4) {	1345	ub_state_stat_counted(sc, cmd);
1249	printk(KERN_NOTICE "%s: "
1250	"tag mismatch orig 0x%x reply 0x%x\n",
1251	sc->name, cmd->tag, bcs->Tag);
1252	goto Bad_End;
1253	}
1254	__ub_state_stat(sc, cmd);
1255	return;	1346	return;
1256	}	1347	}
1257		1348
		1349	rc = le32_to_cpu(bcs->Residue);
		1350	if (rc != cmd->len - cmd->act_len) {
		1351	/*
		1352	* It is all right to transfer less, the caller has
		1353	* to check. But it's not all right if the device
		1354	* counts disagree with our counts.
		1355	*/
		1356	/* P3 */ printk("%s: resid %d len %d act %d\n",
		1357	sc->name, rc, cmd->len, cmd->act_len);
		1358	goto Bad_End;
		1359	}
		1360
1258	switch (bcs->Status) {	1361	switch (bcs->Status) {
1259	case US_BULK_STAT_OK:	1362	case US_BULK_STAT_OK:
1260	break;	1363	break;
@@ -1272,6 +1375,10 @@ static void ub_scsi_urb_compl(struct ub_dev sc, struct ub_scsi_cmd cmd)
1272	}	1375	}
1273		1376
1274	/* Not zeroing error to preserve a babble indicator */	1377	/* Not zeroing error to preserve a babble indicator */
		1378	if (cmd->error != 0) {
		1379	ub_state_sense(sc, cmd);
		1380	return;
		1381	}
1275	cmd->state = UB_CMDST_DONE;	1382	cmd->state = UB_CMDST_DONE;
1276	ub_cmdtr_state(sc, cmd);	1383	ub_cmdtr_state(sc, cmd);
1277	ub_cmdq_pop(sc);	1384	ub_cmdq_pop(sc);
@@ -1310,7 +1417,7 @@ static void ub_state_done(struct ub_dev sc, struct ub_scsi_cmd cmd, int rc)
1310	* Factorization helper for the command state machine:	1417	* Factorization helper for the command state machine:
1311	* Submit a CSW read.	1418	* Submit a CSW read.
1312	*/	1419	*/
1313	static void __ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)	1420	static int __ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)
1314	{	1421	{
1315	int rc;	1422	int rc;
1316		1423
@@ -1328,11 +1435,12 @@ static void __ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)
1328	/* XXX Clear stalls */	1435	/* XXX Clear stalls */
1329	ub_complete(&sc->work_done);	1436	ub_complete(&sc->work_done);
1330	ub_state_done(sc, cmd, rc);	1437	ub_state_done(sc, cmd, rc);
1331	return;	1438	return -1;
1332	}	1439	}
1333		1440
1334	sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;	1441	sc->work_timer.expires = jiffies + UB_STAT_TIMEOUT;
1335	add_timer(&sc->work_timer);	1442	add_timer(&sc->work_timer);
		1443	return 0;
1336	}	1444	}
1337		1445
1338	/*	1446	/*
@@ -1341,7 +1449,9 @@ static void __ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)
1341	*/	1449	*/
1342	static void ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)	1450	static void ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)
1343	{	1451	{
1344	__ub_state_stat(sc, cmd);	1452
		1453	if (__ub_state_stat(sc, cmd) != 0)
		1454	return;
1345		1455
1346	cmd->stat_count = 0;	1456	cmd->stat_count = 0;
1347	cmd->state = UB_CMDST_STAT;	1457	cmd->state = UB_CMDST_STAT;
@@ -1350,6 +1460,25 @@ static void ub_state_stat(struct ub_dev sc, struct ub_scsi_cmd cmd)
1350		1460
1351	/*	1461	/*
1352	* Factorization helper for the command state machine:	1462	* Factorization helper for the command state machine:
		1463	* Submit a CSW read and go to STAT state with counter (along [C] path).
		1464	*/
		1465	static void ub_state_stat_counted(struct ub_dev sc, struct ub_scsi_cmd cmd)
		1466	{
		1467
		1468	if (++cmd->stat_count >= 4) {
		1469	ub_state_sense(sc, cmd);
		1470	return;
		1471	}
		1472
		1473	if (__ub_state_stat(sc, cmd) != 0)
		1474	return;
		1475
		1476	cmd->state = UB_CMDST_STAT;
		1477	ub_cmdtr_state(sc, cmd);
		1478	}
		1479
		1480	/*
		1481	* Factorization helper for the command state machine:
1353	* Submit a REQUEST SENSE and go to SENSE state.	1482	* Submit a REQUEST SENSE and go to SENSE state.
1354	*/	1483	*/
1355	static void ub_state_sense(struct ub_dev sc, struct ub_scsi_cmd cmd)	1484	static void ub_state_sense(struct ub_dev sc, struct ub_scsi_cmd cmd)