device tree based clock lookup, must prepare clocks before enabling
them, error check in the clock setup
this change implements non-fatal clock lookup for compatibility with
platforms that don't provide OF clock specs, but failure to enable a
specified clock is considered fatal
Signed-off-by: Gerhard Sittig <g...@denx.de>
---
arch/powerpc/sysdev/fsl_pci.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index 46ac1dd..cb2ed92 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -17,6 +17,8 @@
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
+
+#include <linux/clk.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
@@ -741,6 +743,7 @@ err0:
int __init mpc83xx_add_bridge(struct device_node *dev)
{
+ struct clk *clk;
int ret;
int len;
struct pci_controller *hose;
@@ -758,6 +761,18 @@ int __init mpc83xx_add_bridge(struct device_node *dev)
}
pr_debug("Adding PCI host bridge %s\n", dev->full_name);
+ /* non-fatal OF clock lookup, but fatal when a clock
+ * was specified yet could not get enabled */
+ clk = of_clk_get_by_name(dev, "per");
+ if (!IS_ERR(clk)) {
+ ret = clk_prepare_enable(clk);
+ clk_put(clk);
+ if (ret) {
+ pr_err("Could not enable peripheral clock\n");
+ return ret;
+ }
+ }
+
/* Fetch host bridge registers address */
if (of_address_to_resource(dev, 0, &rsrc_reg)) {
printk(KERN_WARNING "Can't get pci register base!\n");
--
1.7.10.4
_______________________________________________
devicetree-discuss mailing list
devicetree-discuss@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/devicetree-discuss
