[PATCH 1/2] net: davinci_cpdma: reduce time holding ctlr->lock in cpdma_control_set

[Uwe Kleine-König]

The only user of cpdma_control_set (i.e. cpsw_ndo_open) doesn't check
the return code, so it doesn't matter, which error triggers. So the
checks that are independant of the fields protected by ctlr->lock can be
moved out of the critical section.

Signed-off-by: Uwe Kleine-König <u.kleine-koe...@pengutronix.de>
---
 drivers/net/ethernet/ti/davinci_cpdma.c | 20 +++++++++-----------
 1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/ti/davinci_cpdma.c 
b/drivers/net/ethernet/ti/davinci_cpdma.c
index 73638f7a55d4..5ffa04a306c6 100644
--- a/drivers/net/ethernet/ti/davinci_cpdma.c
+++ b/drivers/net/ethernet/ti/davinci_cpdma.c
@@ -877,23 +877,21 @@ int cpdma_control_set(struct cpdma_ctlr *ctlr, int 
control, int value)
        int ret;
        u32 val;
 
-       spin_lock_irqsave(&ctlr->lock, flags);
-
-       ret = -ENOTSUPP;
        if (!ctlr->params.has_ext_regs)
-               goto unlock_ret;
+               return -ENOTSUPP;
 
-       ret = -EINVAL;
-       if (ctlr->state != CPDMA_STATE_ACTIVE)
-               goto unlock_ret;
-
-       ret = -ENOENT;
        if (control < 0 || control >= ARRAY_SIZE(controls))
-               goto unlock_ret;
+               return -ENOENT;
 
-       ret = -EPERM;
        if ((info->access & ACCESS_WO) != ACCESS_WO)
+               return -EPERM;
+
+       spin_lock_irqsave(&ctlr->lock, flags);
+
+       if (ctlr->state != CPDMA_STATE_ACTIVE) {
+               ret = -EINVAL;
                goto unlock_ret;
+       }
 
        val  = dma_reg_read(ctlr, info->reg);
        val &= ~(info->mask << info->shift);
-- 
2.8.1