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Date:   Fri, 10 Jan 2020 21:21:25 -0800
Message-Id: <20200111052125.238212-1-saravanak@google.com>
Mime-Version: 1.0
Subject: [PATCH v1] clocksource: Avoid creating dead devices
From:   Saravana Kannan <saravanak@google.com>
To:     Daniel Lezcano <daniel.lezcano@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>
Cc:     Saravana Kannan <saravanak@google.com>, kernel-team@android.com,
        linux-kernel@vger.kernel.org
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Sender: linux-kernel-owner@vger.kernel.org
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Timer initialization is done during early boot way before the driver
core starts processing devices and drivers. Timers initialized during
this early boot period don't really need or use a struct device.

However, for timers represented as device tree nodes, the struct devices
are still created and sit around unused and wasting memory. This change
avoid this by marking the device tree nodes as "populated" if the
corresponding timer is successfully initialized.

Signed-off-by: Saravana Kannan <saravanak@google.com>
---
 drivers/clocksource/timer-probe.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clocksource/timer-probe.c b/drivers/clocksource/timer-probe.c
index ee9574da53c0..a10f28d750a9 100644
--- a/drivers/clocksource/timer-probe.c
+++ b/drivers/clocksource/timer-probe.c
@@ -27,8 +27,10 @@ void __init timer_probe(void)
 
 		init_func_ret = match->data;
 
+		of_node_set_flag(np, OF_POPULATED);
 		ret = init_func_ret(np);
 		if (ret) {
+			of_node_clear_flag(np, OF_POPULATED);
 			if (ret != -EPROBE_DEFER)
 				pr_err("Failed to initialize '%pOF': %d\n", np,
 				       ret);
-- 
2.25.0.rc1.283.g88dfdc4193-goog