Module Name: src
Committed By: riastradh
Date: Sat Jul 15 05:46:09 UTC 2017
Modified Files:
src/sys/dev/usb: ualea.c
Log Message:
Tidy up a bit. Fulfil requests completely.
To generate a diff of this commit:
cvs rdiff -u -r1.6 -r1.7 src/sys/dev/usb/ualea.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/usb/ualea.c
diff -u src/sys/dev/usb/ualea.c:1.6 src/sys/dev/usb/ualea.c:1.7
--- src/sys/dev/usb/ualea.c:1.6 Wed Apr 19 00:01:38 2017
+++ src/sys/dev/usb/ualea.c Sat Jul 15 05:46:09 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: ualea.c,v 1.6 2017/04/19 00:01:38 riastradh Exp $ */
+/* $NetBSD: ualea.c,v 1.7 2017/07/15 05:46:09 riastradh Exp $ */
/*-
* Copyright (c) 2017 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ualea.c,v 1.6 2017/04/19 00:01:38 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ualea.c,v 1.7 2017/07/15 05:46:09 riastradh Exp $");
#include <sys/types.h>
#include <sys/atomic.h>
@@ -47,16 +47,21 @@ __KERNEL_RCSID(0, "$NetBSD: ualea.c,v 1.
struct ualea_softc {
device_t sc_dev;
- struct usbd_device *sc_udev;
- struct usbd_interface *sc_uif;
kmutex_t sc_lock;
krndsource_t sc_rnd;
uint16_t sc_maxpktsize;
struct usbd_pipe *sc_pipe;
+ /*
+ * Lock covers:
+ * - sc_needed
+ * - sc_attached
+ * - sc_inflight
+ * - usbd_transfer(sc_xfer)
+ */
struct usbd_xfer *sc_xfer;
+ size_t sc_needed;
bool sc_attached:1;
bool sc_inflight:1;
- /* lock covers sc_attached, sc_inflight, and usbd_transfer(sc_xfer) */
};
static int ualea_match(device_t, cfdata_t, void *);
@@ -88,28 +93,26 @@ ualea_attach(device_t parent, device_t s
{
struct usbif_attach_arg *uiaa = aux;
struct ualea_softc *sc = device_private(self);
- struct usbd_device *udev = uiaa->uiaa_device;
- struct usbd_interface *uif = uiaa->uiaa_iface;
const usb_endpoint_descriptor_t *ed;
char *devinfop;
usbd_status status;
+ /* Print the device info. */
aprint_naive("\n");
aprint_normal("\n");
-
- devinfop = usbd_devinfo_alloc(udev, 0);
+ devinfop = usbd_devinfo_alloc(uiaa->uiaa_device, 0);
aprint_normal_dev(self, "%s\n", devinfop);
usbd_devinfo_free(devinfop);
+ /* Initialize the softc. */
sc->sc_dev = self;
- sc->sc_udev = udev;
- sc->sc_uif = uif;
mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_SOFTUSB);
rndsource_setcb(&sc->sc_rnd, ualea_get, sc);
rnd_attach_source(&sc->sc_rnd, device_xname(self), RND_TYPE_RNG,
RND_FLAG_COLLECT_VALUE|RND_FLAG_HASCB);
- ed = usbd_interface2endpoint_descriptor(uif, 0);
+ /* Get endpoint descriptor 0. Make sure it's bulk-in. */
+ ed = usbd_interface2endpoint_descriptor(uiaa->uiaa_iface, 0);
if (ed == NULL) {
aprint_error_dev(sc->sc_dev, "failed to read endpoint 0\n");
return;
@@ -120,9 +123,11 @@ ualea_attach(device_t parent, device_t s
return;
}
+ /* Remember the maximum packet size. */
sc->sc_maxpktsize = UGETW(ed->wMaxPacketSize);
- status = usbd_open_pipe(uif, ed->bEndpointAddress,
+ /* Open an exclusive MP-safe pipe for endpoint 0. */
+ status = usbd_open_pipe(uiaa->uiaa_iface, ed->bEndpointAddress,
USBD_EXCLUSIVE_USE|USBD_MPSAFE, &sc->sc_pipe);
if (status) {
aprint_error_dev(sc->sc_dev, "failed to open pipe: %d\n",
@@ -130,6 +135,7 @@ ualea_attach(device_t parent, device_t s
return;
}
+ /* Create an xfer of maximum packet size, short OK, on the pipe. */
status = usbd_create_xfer(sc->sc_pipe, sc->sc_maxpktsize,
USBD_SHORT_XFER_OK, 0, &sc->sc_xfer);
if (status) {
@@ -138,6 +144,7 @@ ualea_attach(device_t parent, device_t s
return;
}
+ /* Setup the xfer to call ualea_xfer_done with sc. */
usbd_setup_xfer(sc->sc_xfer, sc, usbd_get_buffer(sc->sc_xfer),
sc->sc_maxpktsize, USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT,
ualea_xfer_done);
@@ -178,24 +185,56 @@ ualea_detach(device_t self, int flags)
}
static void
-ualea_get(size_t nbytes, void *cookie)
+ualea_xfer(struct ualea_softc *sc)
{
- struct ualea_softc *sc = cookie;
usbd_status status;
- mutex_enter(&sc->sc_lock);
- if (!sc->sc_attached)
- goto out;
- if (sc->sc_inflight)
- goto out;
- sc->sc_inflight = true;
+ KASSERT(mutex_owned(&sc->sc_lock));
+ KASSERT(sc->sc_attached);
+ KASSERT(!sc->sc_inflight);
+
+ /* Do nothing if we need nothing. */
+ if (sc->sc_needed == 0)
+ return;
+
+ /* Issue xfer or complain if we can't. */
+ /*
+ * XXX Does USBD_NORMAL_COMPLETION (= 0) make sense here? The
+ * xfer can't complete synchronously because of the lock.
+ */
status = usbd_transfer(sc->sc_xfer);
if (status && status != USBD_IN_PROGRESS) {
aprint_error_dev(sc->sc_dev, "failed to issue xfer: %d\n",
status);
/* We failed -- let someone else have a go. */
- sc->sc_inflight = false;
+ return;
}
+
+ /* Mark xfer in-flight. */
+ sc->sc_inflight = true;
+}
+
+static void
+ualea_get(size_t nbytes, void *cookie)
+{
+ struct ualea_softc *sc = cookie;
+
+ mutex_enter(&sc->sc_lock);
+
+ /* Do nothing if not yet attached. */
+ if (!sc->sc_attached)
+ goto out;
+
+ /* Update how many bytes we need. */
+ sc->sc_needed = MAX(sc->sc_needed, nbytes);
+
+ /* Do nothing if xfer is already in flight. */
+ if (sc->sc_inflight)
+ goto out;
+
+ /* Issue xfer. */
+ ualea_xfer(sc);
+
out: mutex_exit(&sc->sc_lock);
}
@@ -226,9 +265,17 @@ ualea_xfer_done(struct usbd_xfer *xfer,
rnd_add_data(&sc->sc_rnd, pkt, pktsize, NBBY*pktsize);
out:
- /* Allow subsequent transfers. */
mutex_enter(&sc->sc_lock);
+
+ /* Debit what we contributed from what we need. */
+ sc->sc_needed -= MIN(sc->sc_needed, pktsize);
+
+ /* Mark xfer done. */
sc->sc_inflight = false;
+
+ /* Reissue xfer if we still need more. */
+ ualea_xfer(sc);
+
mutex_exit(&sc->sc_lock);
}
