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authorAnatolij Gustschin <agust@denx.de>2012-08-29 21:33:28 +0000
committerAnatolij Gustschin <agust@denx.de>2012-09-14 10:15:35 +0200
commit9d9fd8871b4136755160bf95a9abd0d23d738ddc (patch)
tree9eda535f9a3aea4ed39290ff1fb611035d3b9a7e /arch/powerpc/platforms/52xx
parent00e4b1975bbcd10445808cec0a3a1442e8deca53 (diff)
downloadlinaro-lsk-9d9fd8871b4136755160bf95a9abd0d23d738ddc.tar.gz
powerpc/mpc52xx_lpbfifo: optionally defer fifo transfer start
Currently fifo transfer is started when submitting a transfer request. Add posibility to defer the fifo transfer and start it later by calling additional function. This change is backward compatible, the behaviour of mpc52xx_lpbfifo_submit() is the same for previous driver users, so there is no need to adapt them. Signed-off-by: Anatolij Gustschin <agust@denx.de>
Diffstat (limited to 'arch/powerpc/platforms/52xx')
-rw-r--r--arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c35
1 files changed, 34 insertions, 1 deletions
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c b/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
index d61fb1c0c1a..2351f9e0fb6 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c
@@ -170,7 +170,8 @@ static void mpc52xx_lpbfifo_kick(struct mpc52xx_lpbfifo_request *req)
out_be32(lpbfifo.regs + LPBFIFO_REG_CONTROL, bit_fields);
/* Kick it off */
- out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
+ if (!lpbfifo.req->defer_xfer_start)
+ out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
if (dma)
bcom_enable(lpbfifo.bcom_cur_task);
}
@@ -421,6 +422,38 @@ int mpc52xx_lpbfifo_submit(struct mpc52xx_lpbfifo_request *req)
}
EXPORT_SYMBOL(mpc52xx_lpbfifo_submit);
+int mpc52xx_lpbfifo_start_xfer(struct mpc52xx_lpbfifo_request *req)
+{
+ unsigned long flags;
+
+ if (!lpbfifo.regs)
+ return -ENODEV;
+
+ spin_lock_irqsave(&lpbfifo.lock, flags);
+
+ /*
+ * If the req pointer is already set and a transfer was
+ * started on submit, then this transfer is in progress
+ */
+ if (lpbfifo.req && !lpbfifo.req->defer_xfer_start) {
+ spin_unlock_irqrestore(&lpbfifo.lock, flags);
+ return -EBUSY;
+ }
+
+ /*
+ * If the req was previously submitted but not
+ * started, start it now
+ */
+ if (lpbfifo.req && lpbfifo.req == req &&
+ lpbfifo.req->defer_xfer_start) {
+ out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
+ }
+
+ spin_unlock_irqrestore(&lpbfifo.lock, flags);
+ return 0;
+}
+EXPORT_SYMBOL(mpc52xx_lpbfifo_start_xfer);
+
void mpc52xx_lpbfifo_abort(struct mpc52xx_lpbfifo_request *req)
{
unsigned long flags;