dmaengine: PL08x: get rid of write only pool_ctr and free_txd locking

The free function says the pl08x lock should be taken before calling
it.  However, the DMA pool allocation/freeing is already properly
locked.  The only thing that would need this is pool_ctr, which
happens to be a write-only variable.

Let's get rid of this, and eliminate any need for additional locking
here.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2012-05-26 16:33:39 +01:00
parent aa4afb754d
commit 70f3ff434d

View File

@ -247,7 +247,6 @@ struct pl08x_dma_chan {
* @pd: platform data passed in from the platform/machine
* @phy_chans: array of data for the physical channels
* @pool: a pool for the LLI descriptors
* @pool_ctr: counter of LLIs in the pool
* @lli_buses: bitmask to or in to LLI pointer selecting AHB port for LLI
* fetches
* @mem_buses: set to indicate memory transfers on AHB2.
@ -262,7 +261,6 @@ struct pl08x_driver_data {
struct pl08x_platform_data *pd;
struct pl08x_phy_chan *phy_chans;
struct dma_pool *pool;
int pool_ctr;
u8 lli_buses;
u8 mem_buses;
};
@ -821,8 +819,6 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
return 0;
}
pl08x->pool_ctr++;
bd.txd = txd;
bd.lli_bus = (pl08x->lli_buses & PL08X_AHB2) ? PL080_LLI_LM_AHB2 : 0;
cctl = txd->cctl;
@ -1038,18 +1034,14 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
return num_llis;
}
/* You should call this with the struct pl08x lock held */
static void pl08x_free_txd(struct pl08x_driver_data *pl08x,
struct pl08x_txd *txd)
{
struct pl08x_sg *dsg, *_dsg;
/* Free the LLI */
if (txd->llis_va)
dma_pool_free(pl08x->pool, txd->llis_va, txd->llis_bus);
pl08x->pool_ctr--;
list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) {
list_del(&dsg->node);
kfree(dsg);
@ -1090,8 +1082,6 @@ static void pl08x_desc_free(struct virt_dma_desc *vd)
{
struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
struct pl08x_dma_chan *plchan = to_pl08x_chan(vd->tx.chan);
struct pl08x_driver_data *pl08x = plchan->host;
unsigned long flags;
if (!plchan->slave)
pl08x_unmap_buffers(txd);
@ -1099,9 +1089,7 @@ static void pl08x_desc_free(struct virt_dma_desc *vd)
if (!txd->done)
pl08x_release_mux(plchan);
spin_lock_irqsave(&pl08x->lock, flags);
pl08x_free_txd(plchan->host, txd);
spin_unlock_irqrestore(&pl08x->lock, flags);
}
static void pl08x_free_txd_list(struct pl08x_driver_data *pl08x,