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ASoC: max98504: Add missing MAX98504 on SND_SOC_ALL_CODECS
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1 #include <linux/ftrace.h>
2 #include <linux/percpu.h>
3 #include <linux/slab.h>
4 #include <asm/cacheflush.h>
5 #include <asm/debug-monitors.h>
6 #include <asm/pgtable.h>
7 #include <asm/memory.h>
8 #include <asm/mmu_context.h>
9 #include <asm/smp_plat.h>
10 #include <asm/suspend.h>
11 #include <asm/tlbflush.h>
12
13 /*
14 * This is allocated by cpu_suspend_init(), and used to store a pointer to
15 * the 'struct sleep_stack_data' the contains a particular CPUs state.
16 */
17 unsigned long *sleep_save_stash;
18
19 /*
20 * This hook is provided so that cpu_suspend code can restore HW
21 * breakpoints as early as possible in the resume path, before reenabling
22 * debug exceptions. Code cannot be run from a CPU PM notifier since by the
23 * time the notifier runs debug exceptions might have been enabled already,
24 * with HW breakpoints registers content still in an unknown state.
25 */
26 static int (*hw_breakpoint_restore)(unsigned int);
27 void __init cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int))
28 {
29 /* Prevent multiple restore hook initializations */
30 if (WARN_ON(hw_breakpoint_restore))
31 return;
32 hw_breakpoint_restore = hw_bp_restore;
33 }
34
35 void notrace __cpu_suspend_exit(void)
36 {
37 unsigned int cpu = smp_processor_id();
38
39 /*
40 * We are resuming from reset with the idmap active in TTBR0_EL1.
41 * We must uninstall the idmap and restore the expected MMU
42 * state before we can possibly return to userspace.
43 */
44 cpu_uninstall_idmap();
45
46 /*
47 * Restore per-cpu offset before any kernel
48 * subsystem relying on it has a chance to run.
49 */
50 set_my_cpu_offset(per_cpu_offset(cpu));
51
52 /*
53 * Restore HW breakpoint registers to sane values
54 * before debug exceptions are possibly reenabled
55 * through local_dbg_restore.
56 */
57 if (hw_breakpoint_restore)
58 hw_breakpoint_restore(cpu);
59 }
60
61 /*
62 * cpu_suspend
63 *
64 * arg: argument to pass to the finisher function
65 * fn: finisher function pointer
66 *
67 */
68 int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
69 {
70 int ret = 0;
71 unsigned long flags;
72 struct sleep_stack_data state;
73
74 /*
75 * From this point debug exceptions are disabled to prevent
76 * updates to mdscr register (saved and restored along with
77 * general purpose registers) from kernel debuggers.
78 */
79 local_dbg_save(flags);
80
81 /*
82 * Function graph tracer state gets incosistent when the kernel
83 * calls functions that never return (aka suspend finishers) hence
84 * disable graph tracing during their execution.
85 */
86 pause_graph_tracing();
87
88 if (__cpu_suspend_enter(&state)) {
89 /* Call the suspend finisher */
90 ret = fn(arg);
91
92 /*
93 * Never gets here, unless the suspend finisher fails.
94 * Successful cpu_suspend() should return from cpu_resume(),
95 * returning through this code path is considered an error
96 * If the return value is set to 0 force ret = -EOPNOTSUPP
97 * to make sure a proper error condition is propagated
98 */
99 if (!ret)
100 ret = -EOPNOTSUPP;
101 } else {
102 __cpu_suspend_exit();
103 }
104
105 unpause_graph_tracing();
106
107 /*
108 * Restore pstate flags. OS lock and mdscr have been already
109 * restored, so from this point onwards, debugging is fully
110 * renabled if it was enabled when core started shutdown.
111 */
112 local_dbg_restore(flags);
113
114 return ret;
115 }
116
117 static int __init cpu_suspend_init(void)
118 {
119 /* ctx_ptr is an array of physical addresses */
120 sleep_save_stash = kcalloc(mpidr_hash_size(), sizeof(*sleep_save_stash),
121 GFP_KERNEL);
122
123 if (WARN_ON(!sleep_save_stash))
124 return -ENOMEM;
125
126 return 0;
127 }
128 early_initcall(cpu_suspend_init);