[PATCH 5.4 009/222] bus: ti-sysc: Fix iterating over clocks

Greg Kroah-Hartman
2020-01-22T13:18:10Z

From: Tony Lindgren <tony@atomide.com>

commit 2c81f0f6d3f52ac222a5dc07a6e5c06e1543e88b upstream.

Commit d878970f6ce1 ("bus: ti-sysc: Add separate functions for handling
clocks") separated handling of optional clocks from the main clocks, but
introduced an issue where we do not necessarily allocate a slot for both
fck and ick clocks, but still assume fixed slots for enumerating over the
clocks.

Let's fix the issue by ensuring we always have slots for both fck and ick
even if we don't use ick, and don't attempt to enumerate optional clocks
if not allocated.

In the long run we might want to simplify things a bit by only allocating
space only for the optional clocks as we have only few devices with
optional clocks.

Fixes: d878970f6ce1 ("bus: ti-sysc: Add separate functions for handling clocks")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/bus/ti-sysc.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -343,6 +343,12 @@ static int sysc_get_clocks(struct sysc *
return -EINVAL;
}

+ /* Always add a slot for main clocks fck and ick even if unused */
+ if (!nr_fck)
+ ddata->nr_clocks++;
+ if (!nr_ick)
+ ddata->nr_clocks++;
+
ddata->clocks = devm_kcalloc(ddata->dev,
ddata->nr_clocks, sizeof(*ddata->clocks),
GFP_KERNEL);
@@ -421,7 +427,7 @@ static int sysc_enable_opt_clocks(struct
struct clk *clock;
int i, error;

- if (!ddata->clocks)
+ if (!ddata->clocks || ddata->nr_clocks < SYSC_OPTFCK0 + 1)
return 0;

for (i = SYSC_OPTFCK0; i < SYSC_MAX_CLOCKS; i++) {
@@ -455,7 +461,7 @@ static void sysc_disable_opt_clocks(stru
struct clk *clock;
int i;

- if (!ddata->clocks)
+ if (!ddata->clocks || ddata->nr_clocks < SYSC_OPTFCK0 + 1)
return;

for (i = SYSC_OPTFCK0; i < SYSC_MAX_CLOCKS; i++) {