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| author | Anatolij Gustschin <agust@denx.de> | 2012-08-29 23:33:28 +0200 |
|---|---|---|
| committer | Anatolij Gustschin <agust@denx.de> | 2012-09-14 10:15:35 +0200 |
| commit | 9d9fd8871b4136755160bf95a9abd0d23d738ddc (patch) | |
| tree | 9eda535f9a3aea4ed39290ff1fb611035d3b9a7e /arch/powerpc | |
| parent | dt/misc: add bindings documentation for ifm camera sensor interface (diff) | |
| download | linux-9d9fd8871b4136755160bf95a9abd0d23d738ddc.tar.xz linux-9d9fd8871b4136755160bf95a9abd0d23d738ddc.zip | |
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')
| -rw-r--r-- | arch/powerpc/include/asm/mpc52xx.h | 2 | ||||
| -rw-r--r-- | arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c | 35 |
2 files changed, 36 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/mpc52xx.h b/arch/powerpc/include/asm/mpc52xx.h index 1f41382eda38..0acc7c7c28d1 100644 --- a/arch/powerpc/include/asm/mpc52xx.h +++ b/arch/powerpc/include/asm/mpc52xx.h @@ -307,6 +307,7 @@ struct mpc52xx_lpbfifo_request { size_t size; size_t pos; /* current position of transfer */ int flags; + int defer_xfer_start; /* What to do when finished */ void (*callback)(struct mpc52xx_lpbfifo_request *); @@ -323,6 +324,7 @@ struct mpc52xx_lpbfifo_request { extern int mpc52xx_lpbfifo_submit(struct mpc52xx_lpbfifo_request *req); extern void mpc52xx_lpbfifo_abort(struct mpc52xx_lpbfifo_request *req); extern void mpc52xx_lpbfifo_poll(void); +extern int mpc52xx_lpbfifo_start_xfer(struct mpc52xx_lpbfifo_request *req); /* mpc52xx_pic.c */ extern void mpc52xx_init_irq(void); diff --git a/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c b/arch/powerpc/platforms/52xx/mpc52xx_lpbfifo.c index d61fb1c0c1a0..2351f9e0fb6f 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; |