[PATCH] watchdog: lpc18xx: Use devm_clk_get_enabled() helper

From: Christophe JAILLET
Date: Sat Dec 31 2022 - 07:26:54 EST


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 and avoids the need of a dedicated function used
with devm_add_action_or_reset().

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Note that the order of operations is slightly modified by this patch. The
"reg" clk is now prepare_enable()'ed before clk_get("wdtclk").
---
drivers/watchdog/lpc18xx_wdt.c | 30 ++----------------------------
1 file changed, 2 insertions(+), 28 deletions(-)

diff --git a/drivers/watchdog/lpc18xx_wdt.c b/drivers/watchdog/lpc18xx_wdt.c
index 60b6d74f267d..1b9b5f21a0df 100644
--- a/drivers/watchdog/lpc18xx_wdt.c
+++ b/drivers/watchdog/lpc18xx_wdt.c
@@ -197,16 +197,10 @@ static const struct watchdog_ops lpc18xx_wdt_ops = {
.restart = lpc18xx_wdt_restart,
};

-static void lpc18xx_clk_disable_unprepare(void *data)
-{
- clk_disable_unprepare(data);
-}
-
static int lpc18xx_wdt_probe(struct platform_device *pdev)
{
struct lpc18xx_wdt_dev *lpc18xx_wdt;
struct device *dev = &pdev->dev;
- int ret;

lpc18xx_wdt = devm_kzalloc(dev, sizeof(*lpc18xx_wdt), GFP_KERNEL);
if (!lpc18xx_wdt)
@@ -216,38 +210,18 @@ static int lpc18xx_wdt_probe(struct platform_device *pdev)
if (IS_ERR(lpc18xx_wdt->base))
return PTR_ERR(lpc18xx_wdt->base);

- lpc18xx_wdt->reg_clk = devm_clk_get(dev, "reg");
+ lpc18xx_wdt->reg_clk = devm_clk_get_enabled(dev, "reg");
if (IS_ERR(lpc18xx_wdt->reg_clk)) {
dev_err(dev, "failed to get the reg clock\n");
return PTR_ERR(lpc18xx_wdt->reg_clk);
}

- lpc18xx_wdt->wdt_clk = devm_clk_get(dev, "wdtclk");
+ lpc18xx_wdt->wdt_clk = devm_clk_get_enabled(dev, "wdtclk");
if (IS_ERR(lpc18xx_wdt->wdt_clk)) {
dev_err(dev, "failed to get the wdt clock\n");
return PTR_ERR(lpc18xx_wdt->wdt_clk);
}

- ret = clk_prepare_enable(lpc18xx_wdt->reg_clk);
- if (ret) {
- dev_err(dev, "could not prepare or enable sys clock\n");
- return ret;
- }
- ret = devm_add_action_or_reset(dev, lpc18xx_clk_disable_unprepare,
- lpc18xx_wdt->reg_clk);
- if (ret)
- return ret;
-
- ret = clk_prepare_enable(lpc18xx_wdt->wdt_clk);
- if (ret) {
- dev_err(dev, "could not prepare or enable wdt clock\n");
- return ret;
- }
- ret = devm_add_action_or_reset(dev, lpc18xx_clk_disable_unprepare,
- lpc18xx_wdt->wdt_clk);
- if (ret)
- return ret;
-
/* We use the clock rate to calculate timeouts */
lpc18xx_wdt->clk_rate = clk_get_rate(lpc18xx_wdt->wdt_clk);
if (lpc18xx_wdt->clk_rate == 0) {
--
2.34.1