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@xxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/dma/dw/core.c | 37 +++++++------------------------------
drivers/dma/dw/internal.h | 2 ++
drivers/dma/dw/platform.c | 25 ++++++++++++++++++++++---
drivers/dma/dw/regs.h | 1 -
4 files changed, 31 insertions(+), 34 deletions(-)
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index 1af731b..614e98f 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>
@@ -1495,13 +1494,6 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
dw->regs = chip->regs;
chip->dw = dw;
- dw->clk = devm_clk_get(chip->dev, "hclk");
- if (IS_ERR(dw->clk))
- return PTR_ERR(dw->clk);
- err = clk_prepare_enable(dw->clk);
- if (err)
- return err;
-
dw_params = dma_read_byaddr(chip->regs, DW_PARAMS);
autocfg = dw_params >> DW_PARAMS_EN & 0x1;
@@ -1509,18 +1501,15 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
if (!pdata && autocfg) {
pdata = devm_kzalloc(chip->dev, sizeof(*pdata), GFP_KERNEL);
- if (!pdata) {
- err = -ENOMEM;
- goto err_pdata;
- }
+ if (!pdata)
+ return -ENOMEM;
/* Fill platform data with the default values */
pdata->is_private = true;
pdata->chan_allocation_order = CHAN_ALLOCATION_ASCENDING;
pdata->chan_priority = CHAN_PRIORITY_ASCENDING;
} else if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS) {
- err = -EINVAL;
- goto err_pdata;
+ return -EINVAL;
}
if (autocfg)
@@ -1530,10 +1519,8 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
dw->chan = devm_kcalloc(chip->dev, nr_channels, sizeof(*dw->chan),
GFP_KERNEL);
- if (!dw->chan) {
- err = -ENOMEM;
- goto err_pdata;
- }
+ if (!dw->chan)
+ return -ENOMEM;
/* Get hardware configuration parameters */
if (autocfg) {
@@ -1563,8 +1550,7 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
sizeof(struct dw_desc), 4, 0);
if (!dw->desc_pool) {
dev_err(chip->dev, "No memory for descriptors dma pool\n");
- err = -ENOMEM;
- goto err_pdata;
+ return -ENOMEM;
}
tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw);
@@ -1572,7 +1558,7 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
err = request_irq(chip->irq, dw_dma_interrupt, IRQF_SHARED,
"dw_dmac", dw);
if (err)
- goto err_pdata;
+ return err;
INIT_LIST_HEAD(&dw->dma.channels);
for (i = 0; i < nr_channels; i++) {
@@ -1672,8 +1658,6 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata)
err_dma_register:
free_irq(chip->irq, dw);
-err_pdata:
- clk_disable_unprepare(dw->clk);
return err;
}
EXPORT_SYMBOL_GPL(dw_dma_probe);
@@ -1695,8 +1679,6 @@ int dw_dma_remove(struct dw_dma_chip *chip)
channel_clear_bit(dw, CH_EN, dwc->mask);
}
- clk_disable_unprepare(dw->clk);
-
return 0;
}
EXPORT_SYMBOL_GPL(dw_dma_remove);
@@ -1706,7 +1688,6 @@ 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);
@@ -1717,8 +1698,6 @@ 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);
@@ -1727,9 +1706,7 @@ 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 32667f9..bd55397 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 c5b339a..b7d0ffd 100644
--- a/drivers/dma/dw/platform.c
+++ b/drivers/dma/dw/platform.c
@@ -201,10 +201,17 @@ 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) {
@@ -219,6 +226,10 @@ 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)
@@ -228,7 +239,10 @@ 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)
@@ -236,6 +250,7 @@ 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
@@ -261,7 +276,10 @@ static int dw_suspend_late(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_early(struct device *dev)
@@ -269,6 +287,7 @@ static int dw_resume_early(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 bb98d3e..f2907d8 100644
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -250,7 +250,6 @@ struct dw_dma {
void __iomem *regs;
struct dma_pool *desc_pool;
struct tasklet_struct tasklet;
- struct clk *clk;
/* channels */
struct dw_dma_chan *chan;
--
2.0.1
--
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