Hi,
I get the following warning when I try to compile the current
andy-tracking kernel:
arch/arm/plat-s3c24xx/dma.c: In function 's3c2410_dma_config':
arch/arm/plat-s3c24xx/dma.c:1049: warning: 'dcon' may be used
uninitialized in this function
If I look at the file around line 1049 it looks like this:
int s3c2410_dma_config(unsigned int channel,
int xferunit)
{
struct s3c2410_dma_chan *chan = lookup_dma_channel(channel);
unsigned int dcon;
pr_debug("%s: chan=%d, xfer_unit=%d, dcon=%08x\n",
__func__, channel, xferunit, dcon);
which indeed doesn't init dcon. However, if I look at
[email protected] (and also upstream linus git) I see
int s3c2410_dma_config(unsigned int channel,
int xferunit,
int dcon)
{
struct s3c2410_dma_chan *chan = lookup_dma_channel(channel);
pr_debug("%s: chan=%d, xfer_unit=%d, dcon=%08x\n",
__func__, channel, xferunit, dcon);
I also found that the file arch/arm/plat-s3c24xx/dma.c differs quite
alot between the two branches. I attached the output of
git diff origin/master origin/andy-tracking --
arch/arm/plat-s3c24xx/dma.c > plat-s3c24xx_dma.c.diff
My question is, do we need a rebase or what is going on there?
Sven
diff --git a/arch/arm/plat-s3c24xx/dma.c b/arch/arm/plat-s3c24xx/dma.c
index aee2aeb..84bbbc6 100644
--- a/arch/arm/plat-s3c24xx/dma.c
+++ b/arch/arm/plat-s3c24xx/dma.c
@@ -31,10 +31,10 @@
#include <asm/irq.h>
#include <mach/hardware.h>
#include <mach/dma.h>
-
#include <mach/map.h>
-#include <plat/dma.h>
+#include <plat/dma-core.h>
+#include <plat/regs-dma.h>
/* io map for dma */
static void __iomem *dma_base;
@@ -1038,14 +1038,13 @@ EXPORT_SYMBOL(s3c2410_dma_ctrl);
/* s3c2410_dma_config
*
* xfersize: size of unit in bytes (1,2,4)
- * dcon: base value of the DCONx register
*/
int s3c2410_dma_config(unsigned int channel,
- int xferunit,
- int dcon)
+ int xferunit)
{
struct s3c2410_dma_chan *chan = lookup_dma_channel(channel);
+ unsigned int dcon;
pr_debug("%s: chan=%d, xfer_unit=%d, dcon=%08x\n",
__func__, channel, xferunit, dcon);
@@ -1055,10 +1054,33 @@ int s3c2410_dma_config(unsigned int channel,
pr_debug("%s: Initial dcon is %08x\n", __func__, dcon);
- dcon |= chan->dcon & dma_sel.dcon_mask;
+ dcon = chan->dcon & dma_sel.dcon_mask;
pr_debug("%s: New dcon is %08x\n", __func__, dcon);
+ switch (chan->req_ch) {
+ case DMACH_I2S_IN:
+ case DMACH_I2S_OUT:
+ case DMACH_PCM_IN:
+ case DMACH_PCM_OUT:
+ case DMACH_MIC_IN:
+ default:
+ dcon |= S3C2410_DCON_HANDSHAKE;
+ dcon |= S3C2410_DCON_SYNC_PCLK;
+ break;
+
+ case DMACH_SDI:
+ /* note, ensure if need HANDSHAKE or not */
+ dcon |= S3C2410_DCON_SYNC_PCLK;
+ break;
+
+ case DMACH_XD0:
+ case DMACH_XD1:
+ dcon |= S3C2410_DCON_HANDSHAKE;
+ dcon |= S3C2410_DCON_SYNC_HCLK;
+ break;
+ }
+
switch (xferunit) {
case 1:
dcon |= S3C2410_DCON_BYTE;
@@ -1150,29 +1172,38 @@ EXPORT_SYMBOL(s3c2410_dma_set_buffdone_fn);
* source: S3C2410_DMASRC_HW: source is hardware
* S3C2410_DMASRC_MEM: source is memory
*
- * hwcfg: the value for xxxSTCn register,
- * bit 0: 0=increment pointer, 1=leave pointer
- * bit 1: 0=source is AHB, 1=source is APB
- *
* devaddr: physical address of the source
*/
int s3c2410_dma_devconfig(int channel,
enum s3c2410_dmasrc source,
- int hwcfg,
unsigned long devaddr)
{
struct s3c2410_dma_chan *chan = lookup_dma_channel(channel);
+ unsigned int hwcfg;
if (chan == NULL)
return -EINVAL;
- pr_debug("%s: source=%d, hwcfg=%08x, devaddr=%08lx\n",
- __func__, (int)source, hwcfg, devaddr);
+ pr_debug("%s: source=%d, devaddr=%08lx\n",
+ __func__, (int)source, devaddr);
chan->source = source;
chan->dev_addr = devaddr;
- chan->hw_cfg = hwcfg;
+
+ switch (chan->req_ch) {
+ case DMACH_XD0:
+ case DMACH_XD1:
+ hwcfg = 0; /* AHB */
+ break;
+
+ default:
+ hwcfg = S3C2410_DISRCC_APB;
+ }
+
+ /* always assume our peripheral desintation is a fixed
+ * address in memory. */
+ hwcfg |= S3C2410_DISRCC_INC;
switch (source) {
case S3C2410_DMASRC_HW:
@@ -1278,8 +1309,8 @@ static int s3c2410_dma_resume(struct sys_device *dev)
printk(KERN_INFO "dma%d: restoring configuration\n", cp->number);
- s3c2410_dma_config(no, cp->xfer_unit, cp->dcon);
- s3c2410_dma_devconfig(no, cp->source, cp->hw_cfg, cp->dev_addr);
+ s3c2410_dma_config(no, cp->xfer_unit);
+ s3c2410_dma_devconfig(no, cp->source, cp->dev_addr);
/* re-select the dma source for this channel */
@@ -1476,6 +1507,7 @@ static struct s3c2410_dma_chan
*s3c2410_dma_map_channel(int channel)
found:
dmach = &s3c2410_chans[ch];
dmach->map = ch_map;
+ dmach->req_ch = channel;
dma_chan_map[channel] = dmach;
/* select the channel */
