Linux-Crypto Archive on lore.kernel.org
 help / color / Atom feed
From: Tony Lindgren <tony@atomide.com>
To: Matt Mackall <mpm@selenic.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org
Cc: linux-crypto@vger.kernel.org,
	"Aaro Koskinen" <aaro.koskinen@iki.fi>,
	"Adam Ford" <aford173@gmail.com>,
	"Pali Rohár" <pali.rohar@gmail.com>,
	"Tero Kristo" <t-kristo@ti.com>,
	"Rob Herring" <robh+dt@kernel.org>,
	devicetree@vger.kernel.org
Subject: [PATCH 3/6] hwrng: omap3-rom - Call clk_prepare() on init and exit only
Date: Fri, 13 Sep 2019 15:09:19 -0700
Message-ID: <20190913220922.29501-4-tony@atomide.com> (raw)
In-Reply-To: <20190913220922.29501-1-tony@atomide.com>

When unloading omap3-rom-rng, we'll get the following:

WARNING: CPU: 0 PID: 100 at drivers/clk/clk.c:948 clk_core_disable

This is because the clock is already disabled by omap3_rom_rng_idle().

Also, we should not call prepare and unprepare except during init, and
only call enable and disable during use.

Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Adam Ford <aford173@gmail.com>
Cc: Pali Rohár <pali.rohar@gmail.com>
Cc: Tero Kristo <t-kristo@ti.com>
Fixes: 1c6b7c2108bd ("hwrng: OMAP3 ROM Random Number Generator support")
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 drivers/char/hw_random/omap3-rom-rng.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/drivers/char/hw_random/omap3-rom-rng.c b/drivers/char/hw_random/omap3-rom-rng.c
--- a/drivers/char/hw_random/omap3-rom-rng.c
+++ b/drivers/char/hw_random/omap3-rom-rng.c
@@ -44,7 +44,7 @@ static void omap3_rom_rng_idle(struct work_struct *work)
 		pr_err("reset failed: %d\n", r);
 		return;
 	}
-	clk_disable_unprepare(rng_clk);
+	clk_disable(rng_clk);
 	rng_idle = 1;
 }
 
@@ -55,13 +55,13 @@ static int omap3_rom_rng_get_random(void *buf, unsigned int count)
 
 	cancel_delayed_work_sync(&idle_work);
 	if (rng_idle) {
-		r = clk_prepare_enable(rng_clk);
+		r = clk_enable(rng_clk);
 		if (r)
 			return r;
 
 		r = omap3_rom_rng_call(0, 0, RNG_GEN_PRNG_HW_INIT);
 		if (r != 0) {
-			clk_disable_unprepare(rng_clk);
+			clk_disable(rng_clk);
 			pr_err("HW init failed: %d\n", r);
 			return -EIO;
 		}
@@ -114,20 +114,32 @@ static int omap3_rom_rng_probe(struct platform_device *pdev)
 		return PTR_ERR(rng_clk);
 	}
 
+	ret = clk_prepare(rng_clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "clk_prepare failed: %i\n", ret);
+		return ret;
+	}
+
 	/* Leave the RNG in reset state. */
-	ret = clk_prepare_enable(rng_clk);
+	ret = clk_enable(rng_clk);
 	if (ret)
-		return ret;
+		goto err_unprepare;
 	omap3_rom_rng_idle(0);
 
 	return hwrng_register(&omap3_rom_rng_ops);
+
+err_unprepare:
+	clk_unprepare(rng_clk);
+
+	return ret;
 }
 
 static int omap3_rom_rng_remove(struct platform_device *pdev)
 {
 	cancel_delayed_work_sync(&idle_work);
 	hwrng_unregister(&omap3_rom_rng_ops);
-	clk_disable_unprepare(rng_clk);
+	clk_unprepare(rng_clk);
+
 	return 0;
 }
 
-- 
2.23.0

  parent reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-13 22:09 [PATCH 0/6] Non-urgent fixes and improvments for omap3-rom-rng Tony Lindgren
2019-09-13 22:09 ` [PATCH 1/6] ARM: OMAP2+: Check omap3-rom-rng for GP device instead of HS device Tony Lindgren
2019-09-13 22:09 ` [PATCH 2/6] hwrng: omap3-rom - Fix missing clock by probing with device tree Tony Lindgren
2019-09-13 22:09 ` Tony Lindgren [this message]
2019-09-14 12:54   ` [PATCH 3/6] hwrng: omap3-rom - Call clk_prepare() on init and exit only Sebastian Reichel
2019-09-14 17:57     ` Tony Lindgren
2019-09-13 22:09 ` [PATCH 4/6] hwrng: omap3-rom - Initialize default quality to get data Tony Lindgren
2019-09-13 22:09 ` [PATCH 5/6] hwrng: omap3-rom - Update to use standard driver data Tony Lindgren
2019-09-13 22:09 ` [PATCH 6/6] hwrng: omap3-rom - Use runtime PM instead of custom functions Tony Lindgren
2019-09-14 13:05 ` [PATCH 0/6] Non-urgent fixes and improvments for omap3-rom-rng Sebastian Reichel
2019-09-14 17:59   ` Tony Lindgren

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190913220922.29501-4-tony@atomide.com \
    --to=tony@atomide.com \
    --cc=aaro.koskinen@iki.fi \
    --cc=aford173@gmail.com \
    --cc=devicetree@vger.kernel.org \
    --cc=herbert@gondor.apana.org.au \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-omap@vger.kernel.org \
    --cc=mpm@selenic.com \
    --cc=pali.rohar@gmail.com \
    --cc=robh+dt@kernel.org \
    --cc=t-kristo@ti.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Crypto Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-crypto/0 linux-crypto/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-crypto linux-crypto/ https://lore.kernel.org/linux-crypto \
		linux-crypto@vger.kernel.org linux-crypto@archiver.kernel.org
	public-inbox-index linux-crypto


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-crypto


AGPL code for this site: git clone https://public-inbox.org/ public-inbox