firewire: add CSR BUSY_TIMEOUT support

Implement the BUSY_TIMEOUT register, which is required for nodes that
support retries.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

1 files changed, 13 insertions, 1 deletions

diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 3d4badb7c79b..9c588fd01250 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -1731,7 +1731,8 @@ static int ohci_enable(struct fw_card *card,
         reg_write(ohci, OHCI1394_ATRetries,
                   OHCI1394_MAX_AT_REQ_RETRIES |
                   (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
-                  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8));
+                  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
+                  (200 << 16));
 
         seconds = lower_32_bits(get_seconds());
         reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);
@@ -2023,6 +2024,10 @@ static u32 ohci_read_csr_reg(struct fw_card *card, int csr_offset)
                 spin_unlock_irqrestore(&ohci->lock, flags);
                 return value;
 
+        case CSR_BUSY_TIMEOUT:
+                value = reg_read(ohci, OHCI1394_ATRetries);
+                return (value >> 4) & 0x0ffff00f;
+
         default:
                 WARN_ON(1);
                 return 0;
@@ -2053,6 +2058,13 @@ static void ohci_write_csr_reg(struct fw_card *card, int csr_offset, u32 value)
                 spin_unlock_irqrestore(&ohci->lock, flags);
                 break;
 
+        case CSR_BUSY_TIMEOUT:
+                value = (value & 0xf) | ((value & 0xf) << 4) |
+                        ((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
+                reg_write(ohci, OHCI1394_ATRetries, value);
+                flush_writes(ohci);
+                break;
+
         default:
                 WARN_ON(1);
                 break;