[linux-yocto] [PATCH 3/6] dmaengine: dw: move clock operations to platform.c

[wan.ahmad.zainie.wan.mohamad at intel.com]

From: Andy Shevchenko <andriy.shevchenko at linux.intel.com>

On BayTrail platform DMA is not functional in the PCI mode, whereby it always
failed and exit at the point when it tries to get a clock. It causes the PCI
mode probe to exit with the error message:
	dw_dmac_pci: probe of 0000:00:1e.0 failed with error -2

This patch moves clock operations to where it belongs to. Thus, the clock is
provided only in ACPI / non-PCI cases.

Reported-by: Chew, Chiau Ee <chiau.ee.chew at intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul at intel.com>
(cherry picked from commit a15636e83eb0dedefcb1221be729023e4c281748)

Conflicts:

	drivers/dma/dw/core.c
	- Backport to Kernel 3.10.61-ltsi. Make the patch apply but
	  retaining the essence of it which is to remove clk related
	  stuff out of core.c file.

Signed-off-by: Maurice Petallo <mauricex.r.petallo at intel.com>
Change-Id: Ia696de420231608cd820fd1e227191db71540a68
Reviewed-on: https://git-gar-1.devtools.intel.com/gerrit/4363
Reviewed-by: Wan Mohamad, Wan Ahmad Zainie <wan.ahmad.zainie.wan.mohamad at intel.com>
---
 drivers/dma/dw/core.c     | 11 -----------
 drivers/dma/dw/internal.h |  2 ++
 drivers/dma/dw/platform.c | 25 ++++++++++++++++++++++---
 drivers/dma/dw/regs.h     |  1 -
 4 files changed, 24 insertions(+), 15 deletions(-)

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 2896d16..384dc6f 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -11,7 +11,6 @@
  */
 
 #include <linux/bitops.h>
-#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
@@ -1509,11 +1508,6 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
 	if (!dw)
 		return -ENOMEM;
 
-	dw->clk = devm_clk_get(chip->dev, "hclk");
-	if (IS_ERR(dw->clk))
-		return PTR_ERR(dw->clk);
-	clk_prepare_enable(dw->clk);
-
 	dw->regs = chip->regs;
 	chip->dw = dw;
 
@@ -1673,7 +1667,6 @@ void dw_dma_shutdown(struct dw_dma_chip *chip)
 	struct dw_dma *dw = chip->dw;
 
 	dw_dma_off(dw);
-	clk_disable_unprepare(dw->clk);
 }
 EXPORT_SYMBOL_GPL(dw_dma_shutdown);
 
@@ -1684,8 +1677,6 @@ int dw_dma_suspend(struct dw_dma_chip *chip)
 	struct dw_dma *dw = chip->dw;
 
 	dw_dma_off(dw);
-	clk_disable_unprepare(dw->clk);
-
 	return 0;
 }
 EXPORT_SYMBOL_GPL(dw_dma_suspend);
@@ -1694,9 +1685,7 @@ int dw_dma_resume(struct dw_dma_chip *chip)
 {
 	struct dw_dma *dw = chip->dw;
 
-	clk_prepare_enable(dw->clk);
 	dma_writel(dw, CFG, DW_CFG_DMA_EN);
-
 	return 0;
 }
 EXPORT_SYMBOL_GPL(dw_dma_resume);
diff --git a/drivers/dma/dw/internal.h b/drivers/dma/dw/internal.h
index 43cc1df..34eb09a 100644
--- a/drivers/dma/dw/internal.h
+++ b/drivers/dma/dw/internal.h
@@ -21,12 +21,14 @@
  * @dev:		struct device of the DMA controller
  * @irq:		irq line
  * @regs:		memory mapped I/O space
+ * @clk:		hclk clock
  * @dw:			struct dw_dma that is filed by dw_dma_probe()
  */
 struct dw_dma_chip {
 	struct device	*dev;
 	int		irq;
 	void __iomem	*regs;
+	struct clk	*clk;
 	struct dw_dma	*dw;
 };
 
diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
index 3b71768..047e776 100644
--- a/drivers/dma/dw/platform.c
+++ b/drivers/dma/dw/platform.c
@@ -205,10 +205,17 @@ static int dw_probe(struct platform_device *pdev)
 
 	chip->dev = dev;
 
-	err = dw_dma_probe(chip, pdata);
+	chip->clk = devm_clk_get(chip->dev, "hclk");
+	if (IS_ERR(chip->clk))
+		return PTR_ERR(chip->clk);
+	err = clk_prepare_enable(chip->clk);
 	if (err)
 		return err;
 
+	err = dw_dma_probe(chip, pdata);
+	if (err)
+		goto err_dw_dma_probe;
+
 	platform_set_drvdata(pdev, chip);
 
 	if (pdev->dev.of_node) {
@@ -223,6 +230,10 @@ static int dw_probe(struct platform_device *pdev)
 		dw_dma_acpi_controller_register(chip->dw);
 
 	return 0;
+
+err_dw_dma_probe:
+	clk_disable_unprepare(chip->clk);
+	return err;
 }
 
 static int dw_remove(struct platform_device *pdev)
@@ -232,7 +243,10 @@ static int dw_remove(struct platform_device *pdev)
 	if (pdev->dev.of_node)
 		of_dma_controller_free(pdev->dev.of_node);
 
-	return dw_dma_remove(chip);
+	dw_dma_remove(chip);
+	clk_disable_unprepare(chip->clk);
+
+	return 0;
 }
 
 static void dw_shutdown(struct platform_device *pdev)
@@ -240,6 +254,7 @@ static void dw_shutdown(struct platform_device *pdev)
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 
 	dw_dma_shutdown(chip);
+	clk_disable_unprepare(chip->clk);
 }
 
 #ifdef CONFIG_OF
@@ -265,7 +280,10 @@ static int dw_suspend_noirq(struct device *dev)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 
-	return dw_dma_suspend(chip);
+	dw_dma_suspend(chip);
+	clk_disable_unprepare(chip->clk);
+
+	return 0;
 }
 
 static int dw_resume_noirq(struct device *dev)
@@ -273,6 +291,7 @@ static int dw_resume_noirq(struct device *dev)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct dw_dma_chip *chip = platform_get_drvdata(pdev);
 
+	clk_prepare_enable(chip->clk);
 	return dw_dma_resume(chip);
 }
 
diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
index 73df90d..10c3ffd 100644
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -251,7 +251,6 @@ struct dw_dma {
 	void __iomem		*regs;
 	struct dma_pool		*desc_pool;
 	struct tasklet_struct	tasklet;
-	struct clk		*clk;
 
 	u8			all_chan_mask;
 
-- 
1.9.1