firewire: reread config ROM when device reset the bus
When a device changes its configuration ROM, it announces this with a
bus reset. firewire-core has to check which node initiated a bus reset
and whether any unit directories went away or were added on this node.
Tested with an IOI FWB-IDE01AB which has its link-on bit set if bus
power is available but does not respond to ROM read requests if self
power is off. This implements
- recognition of the units if self power is switched on after fw-core
gave up the initial attempt to read the config ROM,
- shutdown of the units when self power is switched off.
Also tested with a second PC running Linux/ieee1394. When the eth1394
driver is inserted and removed on that node, fw-core now notices the
addition and removal of the IPv4 unit on the ieee1394 node.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-device.h b/drivers/firewire/fw-device.h
index 0d771fd..5f131f5 100644
--- a/drivers/firewire/fw-device.h
+++ b/drivers/firewire/fw-device.h
@@ -21,6 +21,7 @@
#include <linux/fs.h>
#include <linux/cdev.h>
+#include <linux/rwsem.h>
#include <asm/atomic.h>
enum fw_device_state {
@@ -46,6 +47,11 @@
* fw_device.node_id is guaranteed to be current too.
*
* The same applies to fw_device.card->node_id vs. fw_device.generation.
+ *
+ * fw_device.config_rom and fw_device.config_rom_length may be accessed during
+ * the lifetime of any fw_unit belonging to the fw_device, before device_del()
+ * was called on the last fw_unit. Alternatively, they may be accessed while
+ * holding fw_device_rwsem.
*/
struct fw_device {
atomic_t state;
@@ -53,6 +59,7 @@
int node_id;
int generation;
unsigned max_speed;
+ bool cmc;
struct fw_card *card;
struct device device;
struct list_head link;
@@ -92,8 +99,12 @@
void fw_device_cdev_update(struct fw_device *device);
void fw_device_cdev_remove(struct fw_device *device);
+extern struct rw_semaphore fw_device_rwsem;
extern int fw_cdev_major;
+/*
+ * fw_unit.directory must not be accessed after device_del(&fw_unit.device).
+ */
struct fw_unit {
struct device device;
u32 *directory;