diff options
| author | John Keeping <john@metanate.com> | 2023-04-20 11:38:04 +0100 |
|---|---|---|
| committer | Stephen Boyd <sboyd@kernel.org> | 2023-10-23 20:20:57 -0700 |
| commit | e43d31915cc4fca4e04daeca6c0ff25cc57cf956 (patch) | |
| tree | 47d6133cd16753f97eb293f04d6335fc4234a89e /drivers/clk/clk.c | |
| parent | dcce5cc7826e9c6b3a2443e5e6b7f8d02a103c35 (diff) | |
clk: Allow phase adjustment from debugfs
For testing it may be useful to manually adjust a clock's phase. Add
support for writing to the existing clk_phase debugfs file, with the
written value clamped to [0, 360) to match the behaviour of the
clk_set_phase() function.
This is a dangerous feature, so use the existing define
CLOCK_ALLOW_WRITE_DEBUGFS to allow it only if the source is modified.
Signed-off-by: John Keeping <john@metanate.com>
Link: https://lore.kernel.org/r/20230420103805.125246-1-john@metanate.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Diffstat (limited to 'drivers/clk/clk.c')
| -rw-r--r-- | drivers/clk/clk.c | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 0544615d2a1d..2f0885e4f6bf 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3343,6 +3343,21 @@ static int clk_rate_set(void *data, u64 val) #define clk_rate_mode 0644 +static int clk_phase_set(void *data, u64 val) +{ + struct clk_core *core = data; + int degrees = do_div(val, 360); + int ret; + + clk_prepare_lock(); + ret = clk_core_set_phase_nolock(core, degrees); + clk_prepare_unlock(); + + return ret; +} + +#define clk_phase_mode 0644 + static int clk_prepare_enable_set(void *data, u64 val) { struct clk_core *core = data; @@ -3370,6 +3385,9 @@ DEFINE_DEBUGFS_ATTRIBUTE(clk_prepare_enable_fops, clk_prepare_enable_get, #else #define clk_rate_set NULL #define clk_rate_mode 0444 + +#define clk_phase_set NULL +#define clk_phase_mode 0644 #endif static int clk_rate_get(void *data, u64 *val) @@ -3385,6 +3403,16 @@ static int clk_rate_get(void *data, u64 *val) DEFINE_DEBUGFS_ATTRIBUTE(clk_rate_fops, clk_rate_get, clk_rate_set, "%llu\n"); +static int clk_phase_get(void *data, u64 *val) +{ + struct clk_core *core = data; + + *val = core->phase; + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(clk_phase_fops, clk_phase_get, clk_phase_set, "%llu\n"); + static const struct { unsigned long flag; const char *name; @@ -3575,7 +3603,8 @@ static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry) debugfs_create_file("clk_min_rate", 0444, root, core, &clk_min_rate_fops); debugfs_create_file("clk_max_rate", 0444, root, core, &clk_max_rate_fops); debugfs_create_ulong("clk_accuracy", 0444, root, &core->accuracy); - debugfs_create_u32("clk_phase", 0444, root, &core->phase); + debugfs_create_file("clk_phase", clk_phase_mode, root, core, + &clk_phase_fops); debugfs_create_file("clk_flags", 0444, root, core, &clk_flags_fops); debugfs_create_u32("clk_prepare_count", 0444, root, &core->prepare_count); debugfs_create_u32("clk_enable_count", 0444, root, &core->enable_count); |