[RFC PATCH v2 05/11] MIPS: Alchemy: pci: use clk framework to enable PCI clock

From: Manuel Lauss
Date: Thu Jul 03 2014 - 09:24:24 EST


Use the clock framework to get at the PCI clock source and enable
it on driver initialization.

Signed-off-by: Manuel Lauss <manuel.lauss@xxxxxxxxx>
---
arch/mips/pci/pci-alchemy.c | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
index 912c5f2..adc810f 100644
--- a/arch/mips/pci/pci-alchemy.c
+++ b/arch/mips/pci/pci-alchemy.c
@@ -7,6 +7,7 @@
* Support for all devices (greater than 16) added by David Gathright.
*/

+#include <linux/clk.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/pci.h>
@@ -365,6 +366,7 @@ static int alchemy_pci_probe(struct platform_device *pdev)
void __iomem *virt_io;
unsigned long val;
struct resource *r;
+ struct clk *c;
int ret;

/* need at least PCI IRQ mapping table */
@@ -394,11 +396,24 @@ static int alchemy_pci_probe(struct platform_device *pdev)
goto out1;
}

+ c = clk_get(&pdev->dev, "pci_clko");
+ if (IS_ERR(c)) {
+ dev_err(&pdev->dev, "unable to find PCI clock\n");
+ ret = PTR_ERR(c);
+ goto out2;
+ }
+ ret = clk_prepare_enable(c);
+ if (ret) {
+ dev_err(&pdev->dev, "cannot enable PCI clock\n");
+ clk_put(c);
+ goto out2;
+ }
+
ctx->regs = ioremap_nocache(r->start, resource_size(r));
if (!ctx->regs) {
dev_err(&pdev->dev, "cannot map pci regs\n");
ret = -ENODEV;
- goto out2;
+ goto out5;
}

/* map parts of the PCI IO area */
@@ -466,12 +481,18 @@ static int alchemy_pci_probe(struct platform_device *pdev)
register_syscore_ops(&alchemy_pci_pmops);
register_pci_controller(&ctx->alchemy_pci_ctrl);

+ dev_info(&pdev->dev, "PCI controller at %ld MHz\n",
+ clk_get_rate(c) / 1000000);
+
return 0;

out4:
iounmap(virt_io);
out3:
iounmap(ctx->regs);
+out5:
+ clk_disable_unprepare(c);
+ clk_put(c);
out2:
release_mem_region(r->start, resource_size(r));
out1:
--
2.0.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/