[PATCH] rtc: mxc: Use devm_clk_get_enabled() helper

[PATCH] rtc: mxc: Use devm_clk_get_enabled() helper

[Christophe JAILLET]

The devm_clk_get_enabled() helper:
   - calls devm_clk_get()
   - calls clk_prepare_enable() and registers what is needed in order to
     call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code, the error handling paths and avoid the need of
a dedicated function used with devm_add_action_or_reset().

Based on my test with allyesconfig, this reduces the .o size from:
   text	   data	    bss	    dec	    hex	filename
   6705	   1968	      0	   8673	   21e1	drivers/rtc/rtc-mxc.o
down to:
   6212	   1968	      0	   8180	   1ff4	drivers/rtc/rtc-mxc.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
devm_clk_get_enabled() is new and is part of 6.0-rc1
---
 drivers/rtc/rtc-mxc.c | 27 ++-------------------------
 1 file changed, 2 insertions(+), 25 deletions(-)

diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
index 53d4e253e81f..762cf03345f1 100644
--- a/drivers/rtc/rtc-mxc.c
+++ b/drivers/rtc/rtc-mxc.c
@@ -291,14 +291,6 @@ static const struct rtc_class_ops mxc_rtc_ops = {
 	.alarm_irq_enable	= mxc_rtc_alarm_irq_enable,
 };
 
-static void mxc_rtc_action(void *p)
-{
-	struct rtc_plat_data *pdata = p;
-
-	clk_disable_unprepare(pdata->clk_ref);
-	clk_disable_unprepare(pdata->clk_ipg);
-}
-
 static int mxc_rtc_probe(struct platform_device *pdev)
 {
 	struct rtc_device *rtc;
@@ -341,33 +333,18 @@ static int mxc_rtc_probe(struct platform_device *pdev)
 		rtc->range_max = (1 << 16) * 86400ULL - 1;
 	}
 
-	pdata->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
+	pdata->clk_ipg = devm_clk_get_enabled(&pdev->dev, "ipg");
 	if (IS_ERR(pdata->clk_ipg)) {
 		dev_err(&pdev->dev, "unable to get ipg clock!\n");
 		return PTR_ERR(pdata->clk_ipg);
 	}
 
-	ret = clk_prepare_enable(pdata->clk_ipg);
-	if (ret)
-		return ret;
-
-	pdata->clk_ref = devm_clk_get(&pdev->dev, "ref");
+	pdata->clk_ref = devm_clk_get_enabled(&pdev->dev, "ref");
 	if (IS_ERR(pdata->clk_ref)) {
-		clk_disable_unprepare(pdata->clk_ipg);
 		dev_err(&pdev->dev, "unable to get ref clock!\n");
 		return PTR_ERR(pdata->clk_ref);
 	}
 
-	ret = clk_prepare_enable(pdata->clk_ref);
-	if (ret) {
-		clk_disable_unprepare(pdata->clk_ipg);
-		return ret;
-	}
-
-	ret = devm_add_action_or_reset(&pdev->dev, mxc_rtc_action, pdata);
-	if (ret)
-		return ret;
-
 	rate = clk_get_rate(pdata->clk_ref);
 
 	if (rate == 32768)
-- 
2.34.1

Re: [PATCH] rtc: mxc: Use devm_clk_get_enabled() helper

[Alexandre Belloni]

On Mon, 15 Aug 2022 18:59:23 +0200, Christophe JAILLET wrote:
> The devm_clk_get_enabled() helper:
>    - calls devm_clk_get()
>    - calls clk_prepare_enable() and registers what is needed in order to
>      call clk_disable_unprepare() when needed, as a managed resource.
> 
> This simplifies the code, the error handling paths and avoid the need of
> a dedicated function used with devm_add_action_or_reset().
> 
> [...]

Applied, thanks!

[1/1] rtc: mxc: Use devm_clk_get_enabled() helper
      commit: 25bcfaad5ec4e82aede4270d4925967f8520d4cf

Best regards,

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com