Commit 2d156b78 authored by Chen-Yu Tsai's avatar Chen-Yu Tsai
Browse files

clk: Fix debugfs clk_possible_parents for clks without parent string names 



Following the commit fc0c209c ("clk: Allow parents to be specified
without string names"), the parent name string is not always populated.

Instead, fetch the parents clk_core struct using the appropriate helper,
and read its name directly. If that fails, go through the possible
sources of parent names. The order in which they are used is different
from how parents are looked up, with the global name having precedence
over local fw_name and indices. This makes more sense as a) the
parent_maps structure does not differentiate between legacy global names
and fallback global names, and b) global names likely provide more
information than local fw_names.

Fixes: fc0c209c ("clk: Allow parents to be specified without string names")
Signed-off-by: default avatarChen-Yu Tsai <wens@csie.org>
parent a188339c

drivers/clk/clk.c

+41 −3
Original line number Diff line number Diff line
@@ -3000,12 +3000,50 @@ DEFINE_SHOW_ATTRIBUTE(clk_flags); 
static int possible_parents_show(struct seq_file *s, void *data)

{

	struct clk_core *core = s->private;

	struct clk_core *parent;

	int i;



	for (i = 0; i < core->num_parents - 1; i++)

	/*

	 * Go through the following options to fetch a parent's name.

	 *

	 * 1. Fetch the registered parent clock and use its name

	 * 2. Use the global (fallback) name if specified

	 * 3. Use the local fw_name if provided

	 * 4. Fetch parent clock's clock-output-name if DT index was set

	 *

	 * This may still fail in some cases, such as when the parent is

	 * specified directly via a struct clk_hw pointer, but it isn't

	 * registered (yet).

	 */

	for (i = 0; i < core->num_parents - 1; i++) {

		parent = clk_core_get_parent_by_index(core, i);

		if (parent)

			seq_printf(s, "%s ", parent->name);

		else if (core->parents[i].name)

			seq_printf(s, "%s ", core->parents[i].name);

		else if (core->parents[i].fw_name)

			seq_printf(s, "<%s>(fw) ", core->parents[i].fw_name);

		else if (core->parents[i].index >= 0)

			seq_printf(s, "%s ",

				   of_clk_get_parent_name(core->of_node,

							  core->parents[i].index));

		else

			seq_puts(s, "(missing) ");

	}



	seq_printf(s, "%s\n", core->parents[i].name);

	parent = clk_core_get_parent_by_index(core, i);

	if (parent)

		seq_printf(s, "%s", parent->name);

	else if (core->parents[i].name)

		seq_printf(s, "%s", core->parents[i].name);

	else if (core->parents[i].fw_name)

		seq_printf(s, "<%s>(fw)", core->parents[i].fw_name);

	else if (core->parents[i].index >= 0)

		seq_printf(s, "%s",

			   of_clk_get_parent_name(core->of_node,

						  core->parents[i].index));

	else

		seq_puts(s, "(missing)");



	return 0;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE