Re: [PATCH 18/23] watchdog: 1: Convert to use device managed functions and other improvements

From: Guenter Roeck
Date: Tue Apr 09 2019 - 13:39:04 EST


On Tue, Apr 09, 2019 at 10:23:56AM -0700, Guenter Roeck wrote:
> Use device managed functions to simplify error handling, reduce
> source code size, improve readability, and reduce the likelyhood of bugs.
> Other improvements as listed below.
>
> The conversion was done automatically with coccinelle using the
> following semantic patches. The semantic patches and the scripts
> used to generate this commit log are available at
> https://github.com/groeck/coccinelle-patches
>
> - Replace devm_add_action() followed by failure action with
> devm_add_action_or_reset()
> - Replace 'val = e; return val;' with 'return e;'
> - Introduce local variable 'struct device *dev' and use it instead of
> dereferencing it repeatedly
> - Use devm_watchdog_register_driver() to register watchdog device
>
Hmm, something went wrong with the subject line. Should have been
"watchdog: sprd_wdt:". Sorry for that.

Guenter

> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> drivers/watchdog/sprd_wdt.c | 38 ++++++++++++++++++--------------------
> 1 file changed, 18 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c
> index a63163a93777..14874e9b207b 100644
> --- a/drivers/watchdog/sprd_wdt.c
> +++ b/drivers/watchdog/sprd_wdt.c
> @@ -245,9 +245,7 @@ static u32 sprd_wdt_get_timeleft(struct watchdog_device *wdd)
> u32 val;
>
> val = sprd_wdt_get_cnt_value(wdt);
> - val = val / SPRD_WDT_CNT_STEP;
> -
> - return val;
> + return val / SPRD_WDT_CNT_STEP;
> }
>
> static const struct watchdog_ops sprd_wdt_ops = {
> @@ -269,10 +267,11 @@ static const struct watchdog_info sprd_wdt_info = {
>
> static int sprd_wdt_probe(struct platform_device *pdev)
> {
> + struct device *dev = &pdev->dev;
> struct sprd_wdt *wdt;
> int ret;
>
> - wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
> + wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
> if (!wdt)
> return -ENOMEM;
>
> @@ -280,57 +279,56 @@ static int sprd_wdt_probe(struct platform_device *pdev)
> if (IS_ERR(wdt->base))
> return PTR_ERR(wdt->base);
>
> - wdt->enable = devm_clk_get(&pdev->dev, "enable");
> + wdt->enable = devm_clk_get(dev, "enable");
> if (IS_ERR(wdt->enable)) {
> - dev_err(&pdev->dev, "can't get the enable clock\n");
> + dev_err(dev, "can't get the enable clock\n");
> return PTR_ERR(wdt->enable);
> }
>
> - wdt->rtc_enable = devm_clk_get(&pdev->dev, "rtc_enable");
> + wdt->rtc_enable = devm_clk_get(dev, "rtc_enable");
> if (IS_ERR(wdt->rtc_enable)) {
> - dev_err(&pdev->dev, "can't get the rtc enable clock\n");
> + dev_err(dev, "can't get the rtc enable clock\n");
> return PTR_ERR(wdt->rtc_enable);
> }
>
> wdt->irq = platform_get_irq(pdev, 0);
> if (wdt->irq < 0) {
> - dev_err(&pdev->dev, "failed to get IRQ resource\n");
> + dev_err(dev, "failed to get IRQ resource\n");
> return wdt->irq;
> }
>
> - ret = devm_request_irq(&pdev->dev, wdt->irq, sprd_wdt_isr,
> - IRQF_NO_SUSPEND, "sprd-wdt", (void *)wdt);
> + ret = devm_request_irq(dev, wdt->irq, sprd_wdt_isr, IRQF_NO_SUSPEND,
> + "sprd-wdt", (void *)wdt);
> if (ret) {
> - dev_err(&pdev->dev, "failed to register irq\n");
> + dev_err(dev, "failed to register irq\n");
> return ret;
> }
>
> wdt->wdd.info = &sprd_wdt_info;
> wdt->wdd.ops = &sprd_wdt_ops;
> - wdt->wdd.parent = &pdev->dev;
> + wdt->wdd.parent = dev;
> wdt->wdd.min_timeout = SPRD_WDT_MIN_TIMEOUT;
> wdt->wdd.max_timeout = SPRD_WDT_MAX_TIMEOUT;
> wdt->wdd.timeout = SPRD_WDT_MAX_TIMEOUT;
>
> ret = sprd_wdt_enable(wdt);
> if (ret) {
> - dev_err(&pdev->dev, "failed to enable wdt\n");
> + dev_err(dev, "failed to enable wdt\n");
> return ret;
> }
> - ret = devm_add_action(&pdev->dev, sprd_wdt_disable, wdt);
> + ret = devm_add_action_or_reset(dev, sprd_wdt_disable, wdt);
> if (ret) {
> - sprd_wdt_disable(wdt);
> - dev_err(&pdev->dev, "Failed to add wdt disable action\n");
> + dev_err(dev, "Failed to add wdt disable action\n");
> return ret;
> }
>
> watchdog_set_nowayout(&wdt->wdd, WATCHDOG_NOWAYOUT);
> - watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev);
> + watchdog_init_timeout(&wdt->wdd, 0, dev);
>
> - ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdd);
> + ret = devm_watchdog_register_device(dev, &wdt->wdd);
> if (ret) {
> sprd_wdt_disable(wdt);
> - dev_err(&pdev->dev, "failed to register watchdog\n");
> + dev_err(dev, "failed to register watchdog\n");
> return ret;
> }
> platform_set_drvdata(pdev, wdt);