[PATCH 5/7] UEAGLE: Avoid keyboard driver blocking

[Stanislaw Gruszka]

Ueagle-atm driver load DSP firmware in function, which is running from common
workqueue. In some (error) circumstances loading firmware may sleep for long 
periods (even 60 seconds, depending on timeout). This block keyboard driver, 
which also use common workqueue. To fix problem use custom workqueue 
in ueagle-atm.    

Signed-off-by: Stanislaw Gruszka <stf_xl at wp.pl>
---
 drivers/usb/atm/ueagle-atm.c |   31 ++++++++++++++++++++-----------
 1 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/usb/atm/ueagle-atm.c b/drivers/usb/atm/ueagle-atm.c
index e1f20f2..aa67ef5 100644
--- a/drivers/usb/atm/ueagle-atm.c
+++ b/drivers/usb/atm/ueagle-atm.c
@@ -167,6 +167,7 @@ struct uea_softc {
 	union cmv_dsc cmv_dsc;
 
 	struct work_struct task;
+	struct workqueue_struct *work_q;
 	u16 pageno;
 	u16 ovl;
 
@@ -1830,7 +1831,7 @@ static int uea_start_reset(struct uea_softc *sc)
 	/* start loading DSP */
 	sc->pageno = 0;
 	sc->ovl = 0;
-	schedule_work(&sc->task);
+	queue_work(sc->work_q, &sc->task);
 
 	/* wait for modem ready CMV */
 	ret = wait_cmv_ack(sc);
@@ -2038,13 +2039,13 @@ static void uea_schedule_load_page_e1(struct uea_softc *sc, struct intr_pkt *int
 {
 	sc->pageno = intr->e1_bSwapPageNo;
 	sc->ovl = intr->e1_bOvl >> 4 | intr->e1_bOvl << 4;
-	schedule_work(&sc->task);
+	queue_work(sc->work_q, &sc->task);
 }
 
 static void uea_schedule_load_page_e4(struct uea_softc *sc, struct intr_pkt *intr)
 {
 	sc->pageno = intr->e4_bSwapPageNo;
-	schedule_work(&sc->task);
+	queue_work(sc->work_q, &sc->task);
 }
 
 /*
@@ -2117,6 +2118,13 @@ static int uea_boot(struct uea_softc *sc)
 	init_waitqueue_head(&sc->sync_q);
 	init_waitqueue_head(&sc->cmv_ack_wait);
 
+	sc->work_q = create_workqueue("ueagle-dsp");
+	if (!sc->work_q) {
+		uea_err(INS_TO_USBDEV(sc), "cannot allocate workqueue\n");
+		uea_leaves(INS_TO_USBDEV(sc));
+		return -ENOMEM;
+	}
+
 	if (UEA_CHIP_VERSION(sc) == ADI930)
 		load_XILINX_firmware(sc);
 
@@ -2124,14 +2132,13 @@ static int uea_boot(struct uea_softc *sc)
 	if (!intr) {
 		uea_err(INS_TO_USBDEV(sc),
 		       "cannot allocate interrupt package\n");
-		uea_leaves(INS_TO_USBDEV(sc));
-		return -ENOMEM;
+		goto err0;
 	}
 
 	sc->urb_int = usb_alloc_urb(0, GFP_KERNEL);
 	if (!sc->urb_int) {
 		uea_err(INS_TO_USBDEV(sc), "cannot allocate interrupt URB\n");
-		goto err;
+		goto err1;
 	}
 
 	usb_fill_int_urb(sc->urb_int, sc->usb_dev,
@@ -2144,7 +2151,7 @@ static int uea_boot(struct uea_softc *sc)
 	if (ret < 0) {
 		uea_err(INS_TO_USBDEV(sc),
 		       "urb submition failed with error %d\n", ret);
-		goto err;
+		goto err1;
 	}
 
 	sc->kthread = kthread_run(uea_kthread, sc, "ueagle-atm");
@@ -2158,10 +2165,12 @@ static int uea_boot(struct uea_softc *sc)
 
 err2:
 	usb_kill_urb(sc->urb_int);
-err:
+err1:
 	usb_free_urb(sc->urb_int);
 	sc->urb_int = NULL;
 	kfree(intr);
+err0:
+	destroy_workqueue(sc->work_q);
 	uea_leaves(INS_TO_USBDEV(sc));
 	return -ENOMEM;
 }
@@ -2176,15 +2185,15 @@ static void uea_stop(struct uea_softc *sc)
 	ret = kthread_stop(sc->kthread);
 	uea_dbg(INS_TO_USBDEV(sc), "kthread finish with status %d\n", ret);
 
-	/* stop any pending boot process */
-	flush_scheduled_work();
-
 	uea_request(sc, UEA_SET_MODE, UEA_LOOPBACK_ON, 0, NULL);
 
 	usb_kill_urb(sc->urb_int);
 	kfree(sc->urb_int->transfer_buffer);
 	usb_free_urb(sc->urb_int);
 
+	/* stop any pending boot process, when no one can schedule work */
+	destroy_workqueue(sc->work_q);
+
 	if (sc->dsp_firm)
 		release_firmware(sc->dsp_firm);
 	uea_leaves(INS_TO_USBDEV(sc));