| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* |
| 2 | * i.MX27 Power Management Routines |
| 3 | * |
| 4 | * Based on Freescale's BSP |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/suspend.h> |
| 12 | #include <linux/io.h> |
| 13 | #include <mach/hardware.h> |
| 14 | |
| 15 | static int mx27_suspend_enter(suspend_state_t state) |
| 16 | { |
| 17 | u32 cscr; |
| 18 | switch (state) { |
| 19 | case PM_SUSPEND_MEM: |
| 20 | /* Clear MPEN and SPEN to disable MPLL/SPLL */ |
| 21 | cscr = __raw_readl(MX27_IO_ADDRESS(MX27_CCM_BASE_ADDR)); |
| 22 | cscr &= 0xFFFFFFFC; |
| 23 | __raw_writel(cscr, MX27_IO_ADDRESS(MX27_CCM_BASE_ADDR)); |
| 24 | /* Executes WFI */ |
| 25 | cpu_do_idle(); |
| 26 | break; |
| 27 | |
| 28 | default: |
| 29 | return -EINVAL; |
| 30 | } |
| 31 | return 0; |
| 32 | } |
| 33 | |
| 34 | static const struct platform_suspend_ops mx27_suspend_ops = { |
| 35 | .enter = mx27_suspend_enter, |
| 36 | .valid = suspend_valid_only_mem, |
| 37 | }; |
| 38 | |
| 39 | static int __init mx27_pm_init(void) |
| 40 | { |
| 41 | if (!cpu_is_mx27()) |
| 42 | return 0; |
| 43 | |
| 44 | suspend_set_ops(&mx27_suspend_ops); |
| 45 | return 0; |
| 46 | } |
| 47 | |
| 48 | device_initcall(mx27_pm_init); |