From: Jiada Wang <jiada_wang@mentor.com>
To: <mturquette@baylibre.com>, <sboyd@codeaurora.org>,
<linux-clk@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>, <joshua_frkuska@mentor.com>,
<vladimir_zapolskiy@mentor.com>, <jiada_wang@mentor.com>
Subject: [PATCH] clk: move check of CLK_SET_RATE_GATE flag to clk_propagate_rate_change()
Date: Tue, 23 Aug 2016 17:10:58 +0900 [thread overview]
Message-ID: <1471939858-20925-2-git-send-email-jiada_wang@mentor.com> (raw)
In-Reply-To: <1471939858-20925-1-git-send-email-jiada_wang@mentor.com>
Previously CLK_SET_RATE_GATE flag is only checked in clk_set_rate()
which only ensures the clock being called by clk_set_rate() won't
change rate when it has been prepared if CLK_SET_RATE_GATE flag is set.
But a clk_set_rate() request may propagate rate change to these clocks
from the requested clock's topmost parent clock to all its children,
when any one of these clocks has CLK_SET_RATE_GATE flag set
and it has been prepared, the clk_set_rate() request should fail.
This patch moves check of CLK_SET_RATE_GATE flag to
clk_propagate_rate_change() to ensure all affected clocks will
be checked if their rate will be changed after clk_set_rate().
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
drivers/clk/clk.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 820a939..021c740 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1437,6 +1437,13 @@ static struct clk_core *clk_propagate_rate_change(struct clk_core *core,
if (core->rate == core->new_rate)
return NULL;
+ if ((event == PRE_RATE_CHANGE) &&
+ (core->flags & CLK_SET_RATE_GATE) && core->prepare_count) {
+ pr_err("%s: %s not gated but wants to change rate\n",
+ __func__, core->name);
+ fail_clk = core;
+ }
+
if (core->notifier_count) {
ret = __clk_notify(core, event, core->rate, core->new_rate);
if (ret & NOTIFY_STOP_MASK)
@@ -1571,9 +1578,6 @@ static int clk_core_set_rate_nolock(struct clk_core *core,
if (rate == clk_core_get_rate_nolock(core))
return 0;
- if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count)
- return -EBUSY;
-
/* calculate new rates and get the topmost changed clock */
top = clk_calc_new_rates(core, rate);
if (!top)
--
2.4.5
prev parent reply other threads:[~2016-08-23 8:28 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-23 8:10 [PATCH v3] clk: move check of CLK_SET_RATE_GATE flag to clk_propagate_rate_change() Jiada Wang
2016-08-23 8:10 ` Jiada Wang [this message]
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