2022-08-15 17:19:56

by Christophe JAILLET

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

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 <[email protected]>
---
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

2022-08-23 20:51:36

by Alexandre Belloni

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

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