[PATCH 0/2] hwrng: imx-rngc - use devres for clk and hwrng

[PATCH 0/2] hwrng: imx-rngc - use devres for clk and hwrng

[Martin Kaiser]

Use devres for clock prepare+enable and for hwrng registration.

Martin Kaiser (2):
  hwrng: imx-rngc - use devm_clk_get_enabled
  hwrng: imx-rngc - use devres for hwrng registration

 drivers/char/hw_random/imx-rngc.c | 37 ++++++-------------------------
 1 file changed, 7 insertions(+), 30 deletions(-)

-- 
2.30.2


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 1/2] hwrng: imx-rngc - use devm_clk_get_enabled

[Martin Kaiser]

Use the new devm_clk_get_enabled function to get our clock.

We don't have to disable and unprepare the clock ourselves any more in
error paths and in the remove function.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
---
 drivers/char/hw_random/imx-rngc.c | 25 ++++++-------------------
 1 file changed, 6 insertions(+), 19 deletions(-)

diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 4345df012d8f..23f490204341 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -245,7 +245,7 @@ static int imx_rngc_probe(struct platform_device *pdev)
 	if (IS_ERR(rngc->base))
 		return PTR_ERR(rngc->base);
 
-	rngc->clk = devm_clk_get(&pdev->dev, NULL);
+	rngc->clk = devm_clk_get_enabled(&pdev->dev, NULL);
 	if (IS_ERR(rngc->clk)) {
 		dev_err(&pdev->dev, "Can not get rng_clk\n");
 		return PTR_ERR(rngc->clk);
@@ -255,26 +255,20 @@ static int imx_rngc_probe(struct platform_device *pdev)
 	if (irq < 0)
 		return irq;
 
-	ret = clk_prepare_enable(rngc->clk);
-	if (ret)
-		return ret;
-
 	ver_id = readl(rngc->base + RNGC_VER_ID);
 	rng_type = ver_id >> RNGC_TYPE_SHIFT;
 	/*
 	 * This driver supports only RNGC and RNGB. (There's a different
 	 * driver for RNGA.)
 	 */
-	if (rng_type != RNGC_TYPE_RNGC && rng_type != RNGC_TYPE_RNGB) {
-		ret = -ENODEV;
-		goto err;
-	}
+	if (rng_type != RNGC_TYPE_RNGC && rng_type != RNGC_TYPE_RNGB)
+		return -ENODEV;
 
 	ret = devm_request_irq(&pdev->dev,
 			irq, imx_rngc_irq, 0, pdev->name, (void *)rngc);
 	if (ret) {
 		dev_err(rngc->dev, "Can't get interrupt working.\n");
-		goto err;
+		return ret;
 	}
 
 	init_completion(&rngc->rng_op_done);
@@ -294,14 +288,14 @@ static int imx_rngc_probe(struct platform_device *pdev)
 		ret = imx_rngc_self_test(rngc);
 		if (ret) {
 			dev_err(rngc->dev, "self test failed\n");
-			goto err;
+			return ret;
 		}
 	}
 
 	ret = hwrng_register(&rngc->rng);
 	if (ret) {
 		dev_err(&pdev->dev, "hwrng registration failed\n");
-		goto err;
+		return ret;
 	}
 
 	dev_info(&pdev->dev,
@@ -309,11 +303,6 @@ static int imx_rngc_probe(struct platform_device *pdev)
 		rng_type == RNGC_TYPE_RNGB ? 'B' : 'C',
 		(ver_id >> RNGC_VER_MAJ_SHIFT) & 0xff, ver_id & 0xff);
 	return 0;
-
-err:
-	clk_disable_unprepare(rngc->clk);
-
-	return ret;
 }
 
 static int __exit imx_rngc_remove(struct platform_device *pdev)
@@ -322,8 +311,6 @@ static int __exit imx_rngc_remove(struct platform_device *pdev)
 
 	hwrng_unregister(&rngc->rng);
 
-	clk_disable_unprepare(rngc->clk);
-
 	return 0;
 }
 
-- 
2.30.2


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH 2/2] hwrng: imx-rngc - use devres for hwrng registration

[Martin Kaiser]

Replace hwrng_register with devm_hwrng_register and let devres unregister
our hwrng when the device is removed.

It's possible to do this now that devres also handles clock
disable+uprepare. When we had to disable+unprepare the clock ourselves,
we had to unregister the hwrng before this and couldn't use devres.

There's nothing left to do for imx_rngc_remove, this function can go.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
---
 drivers/char/hw_random/imx-rngc.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 23f490204341..97d8dc931ca6 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -292,7 +292,7 @@ static int imx_rngc_probe(struct platform_device *pdev)
 		}
 	}
 
-	ret = hwrng_register(&rngc->rng);
+	ret = devm_hwrng_register(&pdev->dev, &rngc->rng);
 	if (ret) {
 		dev_err(&pdev->dev, "hwrng registration failed\n");
 		return ret;
@@ -305,15 +305,6 @@ static int imx_rngc_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int __exit imx_rngc_remove(struct platform_device *pdev)
-{
-	struct imx_rngc *rngc = platform_get_drvdata(pdev);
-
-	hwrng_unregister(&rngc->rng);
-
-	return 0;
-}
-
 static int __maybe_unused imx_rngc_suspend(struct device *dev)
 {
 	struct imx_rngc *rngc = dev_get_drvdata(dev);
@@ -346,7 +337,6 @@ static struct platform_driver imx_rngc_driver = {
 		.pm = &imx_rngc_pm_ops,
 		.of_match_table = imx_rngc_dt_ids,
 	},
-	.remove = __exit_p(imx_rngc_remove),
 };
 
 module_platform_driver_probe(imx_rngc_driver, imx_rngc_probe);
-- 
2.30.2


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH 0/2] hwrng: imx-rngc - use devres for clk and hwrng

[Herbert Xu]

On Mon, Aug 15, 2022 at 09:37:41PM +0200, Martin Kaiser wrote:
> Use devres for clock prepare+enable and for hwrng registration.
> 
> Martin Kaiser (2):
>   hwrng: imx-rngc - use devm_clk_get_enabled
>   hwrng: imx-rngc - use devres for hwrng registration
> 
>  drivers/char/hw_random/imx-rngc.c | 37 ++++++-------------------------
>  1 file changed, 7 insertions(+), 30 deletions(-)

All applied.  Thanks. 
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel