Re: [PATCH v6 07/13] rtc: mt6397: improvements of rtc driver

From: Alexandre Belloni
Date: Tue Aug 20 2019 - 15:50:04 EST


On 18/08/2019 15:56:05+0200, Frank Wunderlich wrote:
> From: Josef Friedl <josef.friedl@xxxxxxxx>
>
> - use regmap_read_poll_timeout to drop while-loop
> - use devm-api to drop remove-callback
>
> Suggested-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
> Signed-off-by: Josef Friedl <josef.friedl@xxxxxxxx>
> Signed-off-by: Frank Wunderlich <frank-w@xxxxxxxxxxxxxxx>
Acked-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>

> ---
> changes since v5: none
> changes since v4: none
> changes since v3: none
> changes since v2:
> - fix allocation after irq-request
> - compatible for mt6323 in separate commit => part 5
> ---
> drivers/rtc/rtc-mt6397.c | 51 +++++++++++++++-------------------------
> 1 file changed, 19 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c
> index c08ee5edf865..9370b7fc9f81 100644
> --- a/drivers/rtc/rtc-mt6397.c
> +++ b/drivers/rtc/rtc-mt6397.c
> @@ -4,16 +4,19 @@
> * Author: Tianping.Fang <tianping.fang@xxxxxxxxxxxx>
> */
>
> -#include <linux/delay.h>
> -#include <linux/init.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/mfd/mt6397/core.h>
> #include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/platform_device.h>
> #include <linux/regmap.h>
> #include <linux/rtc.h>
> #include <linux/mfd/mt6397/rtc.h>
> +#include <linux/mod_devicetable.h>
>
> static int mtk_rtc_write_trigger(struct mt6397_rtc *rtc)
> {
> - unsigned long timeout = jiffies + HZ;
> int ret;
> u32 data;
>
> @@ -21,19 +24,13 @@ static int mtk_rtc_write_trigger(struct mt6397_rtc *rtc)
> if (ret < 0)
> return ret;
>
> - while (1) {
> - ret = regmap_read(rtc->regmap, rtc->addr_base + RTC_BBPU,
> - &data);
> - if (ret < 0)
> - break;
> - if (!(data & RTC_BBPU_CBUSY))
> - break;
> - if (time_after(jiffies, timeout)) {
> - ret = -ETIMEDOUT;
> - break;
> - }
> - cpu_relax();
> - }
> + ret = regmap_read_poll_timeout(rtc->regmap,
> + rtc->addr_base + RTC_BBPU, data,
> + !(data & RTC_BBPU_CBUSY),
> + MTK_RTC_POLL_DELAY_US,
> + MTK_RTC_POLL_TIMEOUT);
> + if (ret < 0)
> + dev_err(rtc->dev, "failed to write WRTGE: %d\n", ret);
>
> return ret;
> }
> @@ -266,19 +263,19 @@ static int mtk_rtc_probe(struct platform_device *pdev)
> return rtc->irq;
>
> rtc->regmap = mt6397_chip->regmap;
> - rtc->dev = &pdev->dev;
> mutex_init(&rtc->lock);
>
> platform_set_drvdata(pdev, rtc);
>
> - rtc->rtc_dev = devm_rtc_allocate_device(rtc->dev);
> + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
> if (IS_ERR(rtc->rtc_dev))
> return PTR_ERR(rtc->rtc_dev);
>
> - ret = request_threaded_irq(rtc->irq, NULL,
> - mtk_rtc_irq_handler_thread,
> - IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
> - "mt6397-rtc", rtc);
> + ret = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
> + mtk_rtc_irq_handler_thread,
> + IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
> + "mt6397-rtc", rtc);
> +
> if (ret) {
> dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n",
> rtc->irq, ret);
> @@ -302,15 +299,6 @@ static int mtk_rtc_probe(struct platform_device *pdev)
> return ret;
> }
>
> -static int mtk_rtc_remove(struct platform_device *pdev)
> -{
> - struct mt6397_rtc *rtc = platform_get_drvdata(pdev);
> -
> - free_irq(rtc->irq, rtc);
> -
> - return 0;
> -}
> -
> #ifdef CONFIG_PM_SLEEP
> static int mt6397_rtc_suspend(struct device *dev)
> {
> @@ -349,7 +337,6 @@ static struct platform_driver mtk_rtc_driver = {
> .pm = &mt6397_pm_ops,
> },
> .probe = mtk_rtc_probe,
> - .remove = mtk_rtc_remove,
> };
>
> module_platform_driver(mtk_rtc_driver);
> --
> 2.17.1
>

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