diff options
Diffstat (limited to 'arch/powerpc/kernel/rtas.c')
| -rw-r--r-- | arch/powerpc/kernel/rtas.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c index 1f80f0b8a9ad..bb6f5370c279 100644 --- a/arch/powerpc/kernel/rtas.c +++ b/arch/powerpc/kernel/rtas.c @@ -453,6 +453,32 @@ static struct rtas_function rtas_function_table[] __ro_after_init = { }, }; +/** + * rtas_function_token() - RTAS function token lookup. + * @handle: Function handle, e.g. RTAS_FN_EVENT_SCAN. + * + * Context: Any context. + * Return: the token value for the function if implemented by this platform, + * otherwise RTAS_UNKNOWN_SERVICE. + */ +s32 rtas_function_token(const rtas_fn_handle_t handle) +{ + const size_t index = handle.index; + const bool out_of_bounds = index >= ARRAY_SIZE(rtas_function_table); + + if (WARN_ONCE(out_of_bounds, "invalid function index %zu", index)) + return RTAS_UNKNOWN_SERVICE; + /* + * Various drivers attempt token lookups on non-RTAS + * platforms. + */ + if (!rtas.dev) + return RTAS_UNKNOWN_SERVICE; + + return rtas_function_table[index].token; +} +EXPORT_SYMBOL_GPL(rtas_function_token); + static int rtas_function_cmp(const void *a, const void *b) { const struct rtas_function *f1 = a; @@ -1011,7 +1037,7 @@ static int ibm_errinjct_token; * @....: List of @nargs input parameters. * * Invokes the RTAS function indicated by @token, which the caller - * should obtain via rtas_token(). + * should obtain via rtas_function_token(). * * The @nargs and @nret arguments must match the number of input and * output parameters specified for the RTAS function. |