[PATCH] ub: fix for blank CDs (1872bceb) · Commits · 戴 / test

drivers/block/ub.c

+170 −41

Original line number	Diff line number	Diff line
		@@ -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>
		@@ -37,6 +38,73 @@

		#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 != 0)
		goto Bad_End;

		if (urb->actual_length == 0) {
		if (urb->status == -EOVERFLOW) {
		/*
		* 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.
		* 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.
		*/
		if (++cmd->stat_count >= 4) {
		printk(KERN_NOTICE "%s: unable to get CSW\n",
		sc->name);
		goto Bad_End;
		}
		__ub_state_stat(sc, cmd);
		if (urb->status != 0)
		goto Bad_End;

		if (urb->actual_length == 0) {
		ub_state_stat_counted(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
		* to check. But it's not all right if the device
		* counts disagree with our counts.
		* This is the first reply, so do not perform the check.
		* Instead, remember the signature the device uses
		* for future checks. But do not allow a nul.
		*/
		/* P3 */ printk("%s: resid %d len %d act %d\n",
		sc->name, rc, cmd->len, cmd->act_len);
		goto Bad_End;
		sc->signature = bcs->Signature;
		if (sc->signature == cpu_to_le32(0)) {
		ub_state_stat_counted(sc, cmd);
		return;
		}
		} else {
		if (bcs->Signature != sc->signature) {
		ub_state_stat_counted(sc, cmd);
		return;
		}

		#if 0
		if (bcs->Signature != cpu_to_le32(US_BULK_CS_SIGN) &&
		bcs->Signature != cpu_to_le32(US_BULK_CS_OLYMPUS_SIGN)) {
		/* Windows ignores signatures, so do we. */
		}
		#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) {
		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);
		ub_state_stat_counted(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;
		}

		/*
		@@ -1341,13 +1449,34 @@ 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;
		ub_cmdtr_state(sc, 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.

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