firewire: add CSR cmstr support
Implement the cmstr bit, which is required for cycle master capable
nodes and tested for by the Base 1394 Test Suite.
This bit allows the bus master to disable cycle start packets; there are
bus master implementations that actually do this.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 0e54135..1dcc2e4 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -172,6 +172,7 @@
unsigned quirks;
unsigned int pri_req_max;
u32 bus_time;
+ bool is_root;
/*
* Spinlock for accessing fw_ohci data. Never call out of
@@ -1400,6 +1401,7 @@
unsigned long flags;
void *free_rom = NULL;
dma_addr_t free_rom_bus = 0;
+ bool is_new_root;
reg = reg_read(ohci, OHCI1394_NodeID);
if (!(reg & OHCI1394_NodeID_idValid)) {
@@ -1413,6 +1415,12 @@
ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
OHCI1394_NodeID_nodeNumber);
+ is_new_root = (reg & OHCI1394_NodeID_root) != 0;
+ if (!(ohci->is_root && is_new_root))
+ reg_write(ohci, OHCI1394_LinkControlSet,
+ OHCI1394_LinkControl_cycleMaster);
+ ohci->is_root = is_new_root;
+
reg = reg_read(ohci, OHCI1394_SelfIDCount);
if (reg & OHCI1394_SelfIDCount_selfIDError) {
fw_notify("inconsistent self IDs\n");
@@ -2013,6 +2021,16 @@
u32 value;
switch (csr_offset) {
+ case CSR_STATE_CLEAR:
+ case CSR_STATE_SET:
+ /* the controller driver handles only the cmstr bit */
+ if (ohci->is_root &&
+ (reg_read(ohci, OHCI1394_LinkControlSet) &
+ OHCI1394_LinkControl_cycleMaster))
+ return CSR_STATE_BIT_CMSTR;
+ else
+ return 0;
+
case CSR_NODE_IDS:
return reg_read(ohci, OHCI1394_NodeID) << 16;
@@ -2050,6 +2068,23 @@
unsigned long flags;
switch (csr_offset) {
+ case CSR_STATE_CLEAR:
+ /* the controller driver handles only the cmstr bit */
+ if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
+ reg_write(ohci, OHCI1394_LinkControlClear,
+ OHCI1394_LinkControl_cycleMaster);
+ flush_writes(ohci);
+ }
+ break;
+
+ case CSR_STATE_SET:
+ if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
+ reg_write(ohci, OHCI1394_LinkControlSet,
+ OHCI1394_LinkControl_cycleMaster);
+ flush_writes(ohci);
+ }
+ break;
+
case CSR_NODE_IDS:
reg_write(ohci, OHCI1394_NodeID, value >> 16);
flush_writes(ohci);