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1 /**
2  * 	mpc5xxx_get_bus_frequency - Find the bus frequency for a device
3  * 	@node:	device node
4  *
5  * 	Returns bus frequency (IPS on MPC512x, IPB on MPC52xx),
6  * 	or 0 if the bus frequency cannot be found.
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/of_platform.h>
11 #include <linux/export.h>
12 #include <asm/mpc5xxx.h>
13 
mpc5xxx_get_bus_frequency(struct device_node * node)14 unsigned long mpc5xxx_get_bus_frequency(struct device_node *node)
15 {
16 	struct device_node *np;
17 	const unsigned int *p_bus_freq = NULL;
18 
19 	of_node_get(node);
20 	while (node) {
21 		p_bus_freq = of_get_property(node, "bus-frequency", NULL);
22 		if (p_bus_freq)
23 			break;
24 
25 		np = of_get_parent(node);
26 		of_node_put(node);
27 		node = np;
28 	}
29 	if (node)
30 		of_node_put(node);
31 
32 	return p_bus_freq ? *p_bus_freq : 0;
33 }
34 EXPORT_SYMBOL(mpc5xxx_get_bus_frequency);
35