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Diffstat (limited to 'arch/blackfin/kernel/bfin_dma_5xx.c')
-rw-r--r--arch/blackfin/kernel/bfin_dma_5xx.c52
1 files changed, 20 insertions, 32 deletions
diff --git a/arch/blackfin/kernel/bfin_dma_5xx.c b/arch/blackfin/kernel/bfin_dma_5xx.c
index 3946aff4f414..924c00286bab 100644
--- a/arch/blackfin/kernel/bfin_dma_5xx.c
+++ b/arch/blackfin/kernel/bfin_dma_5xx.c
@@ -37,9 +37,8 @@ static int __init blackfin_dma_init(void)
printk(KERN_INFO "Blackfin DMA Controller\n");
for (i = 0; i < MAX_DMA_CHANNELS; i++) {
- dma_ch[i].chan_status = DMA_CHANNEL_FREE;
+ atomic_set(&dma_ch[i].chan_status, 0);
dma_ch[i].regs = dma_io_base_addr[i];
- mutex_init(&(dma_ch[i].dmalock));
}
/* Mark MEMDMA Channel 0 as requested since we're using it internally */
request_dma(CH_MEM_STREAM0_DEST, "Blackfin dma_memcpy");
@@ -60,7 +59,7 @@ static int proc_dma_show(struct seq_file *m, void *v)
int i;
for (i = 0; i < MAX_DMA_CHANNELS; ++i)
- if (dma_ch[i].chan_status != DMA_CHANNEL_FREE)
+ if (dma_channel_active(i))
seq_printf(m, "%2d: %s\n", i, dma_ch[i].device_id);
return 0;
@@ -107,20 +106,11 @@ int request_dma(unsigned int channel, const char *device_id)
}
#endif
- mutex_lock(&(dma_ch[channel].dmalock));
-
- if ((dma_ch[channel].chan_status == DMA_CHANNEL_REQUESTED)
- || (dma_ch[channel].chan_status == DMA_CHANNEL_ENABLED)) {
- mutex_unlock(&(dma_ch[channel].dmalock));
+ if (atomic_cmpxchg(&dma_ch[channel].chan_status, 0, 1)) {
pr_debug("DMA CHANNEL IN USE \n");
return -EBUSY;
- } else {
- dma_ch[channel].chan_status = DMA_CHANNEL_REQUESTED;
- pr_debug("DMA CHANNEL IS ALLOCATED \n");
}
- mutex_unlock(&(dma_ch[channel].dmalock));
-
#ifdef CONFIG_BF54x
if (channel >= CH_UART2_RX && channel <= CH_UART3_TX) {
unsigned int per_map;
@@ -148,21 +138,20 @@ EXPORT_SYMBOL(request_dma);
int set_dma_callback(unsigned int channel, irq_handler_t callback, void *data)
{
- BUG_ON(channel >= MAX_DMA_CHANNELS ||
- dma_ch[channel].chan_status == DMA_CHANNEL_FREE);
+ int ret;
+ unsigned int irq;
- if (callback != NULL) {
- int ret;
- unsigned int irq = channel2irq(channel);
+ BUG_ON(channel >= MAX_DMA_CHANNELS || !callback ||
+ !atomic_read(&dma_ch[channel].chan_status));
- ret = request_irq(irq, callback, IRQF_DISABLED,
- dma_ch[channel].device_id, data);
- if (ret)
- return ret;
+ irq = channel2irq(channel);
+ ret = request_irq(irq, callback, 0, dma_ch[channel].device_id, data);
+ if (ret)
+ return ret;
+
+ dma_ch[channel].irq = irq;
+ dma_ch[channel].data = data;
- dma_ch[channel].irq = irq;
- dma_ch[channel].data = data;
- }
return 0;
}
EXPORT_SYMBOL(set_dma_callback);
@@ -184,7 +173,7 @@ void free_dma(unsigned int channel)
{
pr_debug("freedma() : BEGIN \n");
BUG_ON(channel >= MAX_DMA_CHANNELS ||
- dma_ch[channel].chan_status == DMA_CHANNEL_FREE);
+ !atomic_read(&dma_ch[channel].chan_status));
/* Halt the DMA */
disable_dma(channel);
@@ -194,9 +183,7 @@ void free_dma(unsigned int channel)
free_irq(dma_ch[channel].irq, dma_ch[channel].data);
/* Clear the DMA Variable in the Channel */
- mutex_lock(&(dma_ch[channel].dmalock));
- dma_ch[channel].chan_status = DMA_CHANNEL_FREE;
- mutex_unlock(&(dma_ch[channel].dmalock));
+ atomic_set(&dma_ch[channel].chan_status, 0);
pr_debug("freedma() : END \n");
}
@@ -210,13 +197,14 @@ int blackfin_dma_suspend(void)
{
int i;
- for (i = 0; i < MAX_DMA_SUSPEND_CHANNELS; ++i) {
- if (dma_ch[i].chan_status == DMA_CHANNEL_ENABLED) {
+ for (i = 0; i < MAX_DMA_CHANNELS; ++i) {
+ if (dma_ch[i].regs->cfg & DMAEN) {
printk(KERN_ERR "DMA Channel %d failed to suspend\n", i);
return -EBUSY;
}
- dma_ch[i].saved_peripheral_map = dma_ch[i].regs->peripheral_map;
+ if (i < MAX_DMA_SUSPEND_CHANNELS)
+ dma_ch[i].saved_peripheral_map = dma_ch[i].regs->peripheral_map;
}
return 0;