Re: [PATCH 2/3] dmaengine: dw_dmac: Enhance device tree support

From: viresh kumar
Date: Fri Oct 12 2012 - 01:47:21 EST


On Fri, Oct 12, 2012 at 11:14 AM, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote:
> dw_dmac driver already supports device tree but it used to have its platform
> data passed the non-DT way.
>
> This patch does following changes:
> - pass platform data via DT, non-DT way still takes precedence if both are used.
> - create generic filter routine
> - Earlier slave information was made available by slave specific filter routines
> in chan->private field. Now, this information would be passed from within dmac
> DT node. Slave drivers would now be required to pass bus_id (a string) as
> parameter to this generic filter(), which would be compared against the slave
> data passed from DT, by the generic filter routine.
> - Update binding document

DT parsing of this patch can be tested with following non-official patch :)


dmaengine: dw_dmac: Add dt params debug routine

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
drivers/dma/dw_dmac.c | 42 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
index 05c1dff..569914d 100644
--- a/drivers/dma/dw_dmac.c
+++ b/drivers/dma/dw_dmac.c
@@ -1504,6 +1504,43 @@ static inline int dw_dma_parse_dt(struct
platform_device *pdev)
}
#endif

+static void dw_dma_parse_dt_debug(struct dw_dma_platform_data *pdata)
+{
+ int i = -1;
+
+ if (!pdata) {
+ printk(KERN_ERR "dw_dma: unable to read info from DT\n");
+ return;
+ }
+
+ printk(KERN_ERR "\nPrinting dw_dma DT info\n");
+
+ printk(KERN_ERR "nr_channels: %x\n", pdata->nr_channels);
+ printk(KERN_ERR "is_private: %x\n", pdata->is_private);
+ printk(KERN_ERR "chan_allocation_order: %x\n",
+ pdata->chan_allocation_order);
+
+ printk(KERN_ERR "chan_priority: %x\n", pdata->chan_priority);
+ printk(KERN_ERR "block_size: %x\n", pdata->block_size);
+
+ printk(KERN_ERR "nr_masters: %x\n", pdata->nr_masters);
+ printk(KERN_ERR "data_width: %d %d %d %d\n", pdata->data_width[0],
+ pdata->data_width[1], pdata->data_width[2],
+ pdata->data_width[3]);
+
+ /* parse slave data */
+ printk(KERN_ERR "slave_info\n");
+
+ while (++i < pdata->sd_count) {
+ printk(KERN_INFO "bus_id: %s\n", pdata->sd[i].bus_id);
+ printk(KERN_INFO "cfg_hi: %x\n", pdata->sd[i].cfg_hi);
+ printk(KERN_INFO "cfg_lo: %x\n", pdata->sd[i].cfg_lo);
+ printk(KERN_INFO "src_master: %x\n",
+ pdata->sd[i].src_master);
+ printk(KERN_INFO "dst_master: %x\n",
+ pdata->sd[i].dst_master);
+ }
+}
static int __devinit dw_probe(struct platform_device *pdev)
{
struct dw_dma_platform_data *pdata;
@@ -1515,9 +1552,12 @@ static int __devinit dw_probe(struct
platform_device *pdev)
int i;

pdata = dev_get_platdata(&pdev->dev);
- if (!pdata)
+ if (!pdata) {
pdata = dw_dma_parse_dt(pdev);
+ dw_dma_parse_dt_debug(pdata);
+ }
--
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