This has minor usbcore cleanups:
DOC:
- the changes passing a usb_interface to driver probe() and disconnect()
weren't reflected in their adjacent docs. likewise they still said
it was possible to get a null usb_device_id (no more).
- the (root) hub API restrictions from rmk's ARM patch weren't
flagged
- mention the non-dma-coherent cache issue for usb_buffer_alloc()
- mention disconnect() cleanup issue with usb_{control,bulk}_msg()
[ you can't cancel those urbs from disconnect() ]
CODE
- make driver ioctl() use 'usb_interface' too ... this update
also resolves an old 'one instance per device' bad assumption
- module locking on driver->ioctl() was goofy, kept BKL way too
long and didn't try_inc_mod_count() like the rest of usbcore
- hcd unlink code treated iso inappropriately like interrupt;
only interrupt still wants that automagic mode
- move iso init out of ohci into shared submit_urb logic
- remove interrupt transfer length restriction; hcds that don't
handle packetization (just like bulk :) should be updated,
but device drivers won't care for now.
Please merge to Linus' latest.
- Dave
--- ./include/linux/usb.h-dist Wed Sep 18 10:25:54 2002
+++ ./include/linux/usb.h Fri Sep 27 11:59:00 2002
@@ -452,9 +452,9 @@
* User mode code can read these tables to choose which modules to load.
* Declare the table as a MODULE_DEVICE_TABLE.
*
- * The third probe() parameter will point to a matching entry from this
- * table. (Null value reserved.) Use the driver_data field for each
- * match to hold information tied to that match: device quirks, etc.
+ * A probe() parameter will point to a matching entry from this table.
+ * Use the driver_info field for each match to hold information tied
+ * to that match: device quirks, etc.
*
* Terminate the driver's table with an all-zeroes entry.
* Use the flag values to control which fields are compared.
@@ -604,17 +604,14 @@
* @name: The driver name should be unique among USB drivers,
* and should normally be the same as the module name.
* @probe: Called to see if the driver is willing to manage a particular
- * interface on a device. The probe routine returns a handle that
- * will later be provided to disconnect(), or a null pointer to
- * indicate that the driver will not handle the interface.
- * The handle is normally a pointer to driver-specific data.
- * If the probe() routine needs to access the interface
- * structure itself, use usb_ifnum_to_if() to make sure it's using
- * the right one.
+ * interface on a device. If it is, probe returns zero and uses
+ * dev_set_drvdata() to associate driver-specific data with the
+ * interface. It may also use usb_set_interface() to specify the
+ * appropriate altsetting. If unwilling to manage the interface,
+ * return a negative errno value.
* @disconnect: Called when the interface is no longer accessible, usually
- * because its device has been (or is being) disconnected. The
- * handle passed is what was returned by probe(), or was provided
- * to usb_driver_claim_interface().
+ * because its device has been (or is being) disconnected or the
+ * driver module is being unloaded.
* @ioctl: Used for drivers that want to talk to userspace through
* the "usbfs" filesystem. This lets devices provide ways to
* expose information to user space regardless of where they
@@ -648,7 +645,7 @@
void (*disconnect) (struct usb_interface *intf);
- int (*ioctl) (struct usb_device *dev, unsigned int code, void *buf);
+ int (*ioctl) (struct usb_interface *intf, unsigned int code, void *buf);
const struct usb_device_id *id_table;
--- ./include/linux/usbdevice_fs.h-dist Wed Jul 17 08:41:40 2002
+++ ./include/linux/usbdevice_fs.h Fri Sep 27 11:50:52 2002
@@ -108,7 +108,7 @@
struct usbdevfs_iso_packet_desc iso_frame_desc[0];
};
-/* ioctls for talking to drivers in the usbcore module: */
+/* ioctls for talking directly to drivers */
struct usbdevfs_ioctl {
int ifno; /* interface 0..N ; negative numbers reserved */
int ioctl_code; /* MUST encode size + direction of data so the
--- ./drivers/usb-dist/core/hcd.c Wed Sep 18 10:25:48 2002
+++ ./drivers/usb/core/hcd.c Fri Sep 27 12:06:45 2002
@@ -1024,6 +1024,11 @@
*/
urb = usb_get_urb (urb);
if (urb->dev == hcd->self.root_hub) {
+ /* NOTE: requirement on hub callers (usbfs and the hub
+ * driver, for now) that URBs' urb->transfer_buffer be
+ * valid and usb_buffer_{sync,unmap}() not be needed, since
+ * they could clobber root hub response data.
+ */
urb->transfer_flags |= URB_NO_DMA_MAP;
return rh_urb_enqueue (hcd, urb);
}
@@ -1132,11 +1137,11 @@
goto done;
}
- /* For non-periodic transfers, any status except -EINPROGRESS means
- * the HCD has already started to unlink this URB from the hardware.
- * In that case, there's no more work to do.
+ /* Except for interrupt transfers, any status except -EINPROGRESS
+ * means the HCD already started to unlink this URB from the hardware.
+ * So there's no more work to do.
*
- * For periodic transfers, this is the only way to trigger unlinking
+ * For interrupt transfers, this is the only way to trigger unlinking
* from the hardware. Since we (currently) overload urb->status to
* tell the driver to unlink, error status might get clobbered ...
* unless that transfer hasn't yet restarted. One such case is when
@@ -1144,13 +1149,10 @@
*
* FIXME use an URB_UNLINKED flag to match URB_TIMEOUT_KILLED
*/
- switch (usb_pipetype (urb->pipe)) {
- case PIPE_CONTROL:
- case PIPE_BULK:
- if (urb->status != -EINPROGRESS) {
- retval = -EINVAL;
- goto done;
- }
+ if (urb->status != -EINPROGRESS
+ && usb_pipetype (urb->pipe) != PIPE_INTERRUPT) {
+ retval = -EINVAL;
+ goto done;
}
/* maybe set up to block on completion notification */
--- ./drivers/usb-dist/core/hub.c Wed Sep 18 10:25:48 2002
+++ ./drivers/usb/core/hub.c Fri Sep 27 11:59:00 2002
@@ -547,8 +547,11 @@
return -ENODEV;
}
-static int hub_ioctl(struct usb_device *hub, unsigned int code, void *user_data)
+static int
+hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
{
+ struct usb_device *hub = interface_to_usbdev (intf);
+
/* assert ifno == 0 (part of hub spec) */
switch (code) {
case USBDEVFS_HUB_PORTINFO: {
--- ./drivers/usb-dist/core/usb.c Fri Sep 27 08:08:16 2002
+++ ./drivers/usb/core/usb.c Fri Sep 27 11:59:00 2002
@@ -123,6 +123,8 @@
if (driver->owner) {
m = try_inc_mod_count(driver->owner);
if (m == 0) {
+ // FIXME this happens even when we just rmmod
+ // drivers that aren't in active use...
err("Dieing driver still bound to device.\n");
return -EIO;
}
@@ -1196,6 +1198,8 @@
* avoid behaviors like using "DMA bounce buffers", or tying down I/O mapping
* hardware for long idle periods. The implementation varies between
* platforms, depending on details of how DMA will work to this device.
+ * Using these buffers also helps prevent cacheline sharing problems on
+ * architectures where CPU caches are not DMA-coherent.
*
* When the buffer is no longer used, free it with usb_buffer_free().
*/
--- ./drivers/usb-dist/core/urb.c Sun Sep 1 22:29:48 2002
+++ ./drivers/usb/core/urb.c Fri Sep 27 12:38:40 2002
@@ -232,22 +232,19 @@
return -EMSGSIZE;
}
- /* "high bandwidth" mode, 1-3 packets/uframe? */
- if (dev->speed == USB_SPEED_HIGH) {
- int mult;
- switch (temp) {
- case PIPE_ISOCHRONOUS:
- case PIPE_INTERRUPT:
- mult = 1 + ((max >> 11) & 0x03);
+ /* periodic transfers limit size per frame/uframe,
+ * but drivers only control those sizes for ISO.
+ * while we're checking, initialize return status.
+ */
+ if (temp == PIPE_ISOCHRONOUS) {
+ int n, len;
+
+ /* "high bandwidth" mode, 1-3 packets/uframe? */
+ if (dev->speed == USB_SPEED_HIGH) {
+ int mult = 1 + ((max >> 11) & 0x03);
max &= 0x03ff;
max *= mult;
}
- }
-
- /* periodic transfers limit size per frame/uframe */
- switch (temp) {
- case PIPE_ISOCHRONOUS: {
- int n, len;
if (urb->number_of_packets <= 0)
return -EINVAL;
@@ -255,13 +252,9 @@
len = urb->iso_frame_desc [n].length;
if (len < 0 || len > max)
return -EMSGSIZE;
+ urb->iso_frame_desc [n].status = -EXDEV;
+ urb->iso_frame_desc [n].actual_length = 0;
}
-
- }
- break;
- case PIPE_INTERRUPT:
- if (urb->transfer_buffer_length > max)
- return -EMSGSIZE;
}
/* the I/O buffer must be mapped/unmapped, except when length=0 */
--- ./drivers/usb-dist/core/devio.c Wed Sep 18 10:25:48 2002
+++ ./drivers/usb/core/devio.c Fri Sep 27 18:38:57 2002
@@ -1067,6 +1067,10 @@
/* disconnect kernel driver from interface, leaving it unbound. */
case USBDEVFS_DISCONNECT:
/* this function is voodoo. */
+ /* which function ... usb_device_remove()?
+ * FIXME either the module lock (BKL) should be involved
+ * here too, or the 'default' case below is broken
+ */
driver = ifp->driver;
if (driver) {
dbg ("disconnect '%s' from dev %d interface %d",
@@ -1081,26 +1085,28 @@
retval = usb_device_probe (&ifp->dev);
break;
- /* talk directly to the interface's driver */
- default:
- lock_kernel(); /* against module unload */
- driver = ifp->driver;
- if (driver == 0 || driver->ioctl == 0) {
+ /* talk directly to the interface's driver */
+ default:
+ /* BKL used here to protect against changing the binding
+ * of this driver to this device, as well as unloading its
+ * driver module.
+ */
+ lock_kernel ();
+ driver = ifp->driver;
+ if (driver == 0 || driver->ioctl == 0) {
unlock_kernel();
retval = -ENOSYS;
} else {
- if (ifp->driver->owner) {
- __MOD_INC_USE_COUNT(ifp->driver->owner);
- unlock_kernel();
- }
- /* ifno might usefully be passed ... */
- retval = driver->ioctl (ps->dev, ctrl.ioctl_code, buf);
- /* size = min_t(int, size, retval)? */
- if (ifp->driver->owner) {
- __MOD_DEC_USE_COUNT(ifp->driver->owner);
- } else {
+ if (driver->owner
+ && !try_inc_mod_count (driver->owner)) {
unlock_kernel();
+ retval = -ENOSYS;
+ break;
}
+ unlock_kernel ();
+ retval = driver->ioctl (ifp, ctrl.ioctl_code, buf);
+ if (driver->owner)
+ __MOD_DEC_USE_COUNT (driver->owner);
}
if (retval == -ENOIOCTLCMD)
--- ./drivers/usb-dist/core/message.c Tue Aug 27 15:46:58 2002
+++ ./drivers/usb/core/message.c Fri Sep 27 11:59:00 2002
@@ -123,6 +123,9 @@
* Don't use this function from within an interrupt context, like a
* bottom half handler. If you need an asynchronous message, or need to send
* a message from within interrupt context, use usb_submit_urb()
+ * If a thread in your driver uses this call, make sure your disconnect()
+ * method can wait for it to complete. Since you don't have a handle on
+ * the URB used, you can't cancel the request.
*/
int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u8
requesttype,
__u16 value, __u16 index, void *data, __u16 size, int timeout)
@@ -170,6 +173,9 @@
* Don't use this function from within an interrupt context, like a
* bottom half handler. If you need an asynchronous message, or need to
* send a message from within interrupt context, use usb_submit_urb()
+ * If a thread in your driver uses this call, make sure your disconnect()
+ * method can wait for it to complete. Since you don't have a handle on
+ * the URB used, you can't cancel the request.
*/
int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
void *data, int len, int *actual_length, int timeout)
--- ./drivers/usb-dist/host/ohci-hcd.c Fri Sep 27 08:08:16 2002
+++ ./drivers/usb/host/ohci-hcd.c Fri Sep 27 11:59:00 2002
@@ -193,12 +193,6 @@
break;
case PIPE_ISOCHRONOUS: /* number of packets from URB */
size = urb->number_of_packets;
- if (size <= 0)
- return -EINVAL;
- for (i = 0; i < urb->number_of_packets; i++) {
- urb->iso_frame_desc [i].actual_length = 0;
- urb->iso_frame_desc [i].status = -EXDEV;
- }
break;
}
