| Wolfgang Denk | 87c441e | 2009-06-17 00:30:22 -0600 | [diff] [blame] | 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 | |
| 12 | unsigned int |
| 13 | mpc5xxx_get_bus_frequency(struct device_node *node) |
| 14 | { |
| 15 | struct device_node *np; |
| 16 | const unsigned int *p_bus_freq = NULL; |
| 17 | |
| 18 | of_node_get(node); |
| 19 | while (node) { |
| 20 | p_bus_freq = of_get_property(node, "bus-frequency", NULL); |
| 21 | if (p_bus_freq) |
| 22 | break; |
| 23 | |
| 24 | np = of_get_parent(node); |
| 25 | of_node_put(node); |
| 26 | node = np; |
| 27 | } |
| 28 | if (node) |
| 29 | of_node_put(node); |
| 30 | |
| 31 | return p_bus_freq ? *p_bus_freq : 0; |
| 32 | } |
| 33 | EXPORT_SYMBOL(mpc5xxx_get_bus_frequency); |