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 13 unsigned int 14 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