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dw_dmac: absence of pdata isn't critical when autocfg is set

PATCH Superseded Andy Shevchenko 2 participants 5 messages Nov 12, 2012 dmaengine

v1 of 2 Superseded Latest is v2 →

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Andy Shevchenko

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#0 lore raw

PATCH 1/1 dw_dmac: absence of pdata isn't critical when autocfg is set

The patch allows to probe the device when platform data is absent and hardware auto configuration is enabled. In that case the default platform data is used where the channel allocation order is set to ascending, channel priority is set to ascending, and private property is set to true.

Signed-off-by Andy Shevchenko <[email protected]>
---
 drivers/dma/dw_dmac.c |   15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)
drivers/dma/dw_dmac.c +12 -3
index 2c8096d..0ec5c84 100644
@@ -1585,6 +1585,12 @@ dw_dma_parse_dt(struct platform_device *pdev)
 }
 #endif
 
+static struct dw_dma_platform_data dw_dma_pdata = {
+	.is_private = true,
+	.chan_allocation_order = CHAN_ALLOCATION_ASCENDING,
+	.chan_priority = CHAN_PRIORITY_ASCENDING,
+};
+
 static int __devinit dw_probe(struct platform_device *pdev)
 {
 	struct dw_dma_platform_data *pdata;

@@ -1604,9 +1610,6 @@ static int __devinit dw_probe(struct platform_device *pdev)
 	if (!pdata)
 		pdata = dw_dma_parse_dt(pdev);
 
-	if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
-		return -EINVAL;
-
 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!io)
 		return -EINVAL;

@@ -1622,6 +1625,12 @@ static int __devinit dw_probe(struct platform_device *pdev)
 	dw_params = dma_read_byaddr(regs, DW_PARAMS);
 	autocfg = dw_params >> DW_PARAMS_EN & 0x1;
 
+	if (!pdata && autocfg)
+		pdata = &dw_dma_pdata;
+
+	if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
+		return -EINVAL;
+
 	if (autocfg)
 		nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 0x7) + 1;
 	else
Signature · 1 line
1.7.10.4
#1 lore raw
Quoted 16 lines · Andy Shevchenko
drivers/dma/dw_dmac.c +0 -3
 
 static int __devinit dw_probe(struct platform_device *pdev)
 {
        struct dw_dma_platform_data *pdata;

@@ -1604,9 +1610,6 @@ static int __devinit dw_probe(struct platform_device *pdev)
        if (!pdata)
                pdata = dw_dma_parse_dt(pdev);
 
-       if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
-               return -EINVAL;
-
        io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!io)
                return -EINVAL;

drivers/dma/dw_dmac.c static int __devinit dw_probe(struct platform_device *pdev) · line 1629

Quoted 5 lines
drivers/dma/dw_dmac.c +2 -0
@@ -1622,6 +1625,12 @@ static int __devinit dw_probe(struct platform_device *pdev)
        dw_params = dma_read_byaddr(regs, DW_PARAMS);
        autocfg = dw_params >> DW_PARAMS_EN & 0x1;
 
+       if (!pdata && autocfg)
+               pdata = &dw_dma_pdata;

Allocate it dynamically to support multiple controllers with different configuration
in a SoC.

author
#2 lore raw
Quoted 21 lines · viresh kumar
Quoted 19 lines · Andy Shevchenko
drivers/dma/dw_dmac.c +0 -3
 
 static int __devinit dw_probe(struct platform_device *pdev)
 {
        struct dw_dma_platform_data *pdata;

@@ -1604,9 +1610,6 @@ static int __devinit dw_probe(struct platform_device *pdev)
        if (!pdata)
                pdata = dw_dma_parse_dt(pdev);
 
-       if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
-               return -EINVAL;
-
        io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!io)
                return -EINVAL;

@@ -1622,6 +1625,12 @@ static int __devinit dw_probe(struct platform_device *pdev)
        dw_params = dma_read_byaddr(regs, DW_PARAMS);
        autocfg = dw_params >> DW_PARAMS_EN & 0x1;
Quoted 6 lines

drivers/dma/dw_dmac.c static int __devinit dw_probe(struct platform_device *pdev) · line 1629

Quoted 2 lines
drivers/dma/dw_dmac.c +2 -0
+       if (!pdata && autocfg)
+               pdata = &dw_dma_pdata;

Allocate it dynamically to support multiple controllers with different configuration
in a SoC.

Like you did for device tree? No problem, but here is the question: what the default values should be and where we can get them?

Signature · 2 lines
Andy Shevchenko <[email protected]>
Intel Finland Oy
#3 lore raw
Quoted 8 lines · Andy Shevchenko
Quoted 3 lines · viresh kumar

Allocate it dynamically to support multiple controllers with different configuration
in a SoC.

Like you did for device tree? No problem, but here is the question: what the default values should be and where we can get them?

Yes. Fill with the values you mentioned in your static definition :)

--
viresh

#4 lore raw
In reply to Andy Shevchenko

drivers/dma/dw_dmac.c static int __devinit dw_probe(struct platform_device *pdev) · line 1633

Quoted 6 lines · Andy Shevchenko
drivers/dma/dw_dmac.c +6 -0
+       if (!pdata && autocfg)
+               pdata = &dw_dma_pdata;
+
+       if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
+               return -EINVAL;
+

Another thing: replace the second if with else if :)