Re: [PATCH v2 1/3] rtc: stm32: rework register management to prepare other version of RTC

From: Amelie DELAUNAY
Date: Thu May 17 2018 - 05:05:43 EST


Hi,

On 05/16/2018 10:25 PM, Alexandre Belloni wrote:
> Hi,
>
> On 09/05/2018 17:46:08+0200, Amelie Delaunay wrote:
>> static void stm32_rtc_wpr_unlock(struct stm32_rtc *rtc)
>> {
>> - writel_relaxed(RTC_WPR_1ST_KEY, rtc->base + STM32_RTC_WPR);
>> - writel_relaxed(RTC_WPR_2ND_KEY, rtc->base + STM32_RTC_WPR);
>> + struct stm32_rtc_registers regs = rtc->data->regs;
>
> regs should probably be a pointer to ensure that no copy is made. I've
> actually checked and it doesn't make a difference because gcc is smart
> enough to not make the copy.
>

...

>> static irqreturn_t stm32_rtc_alarm_irq(int irq, void *dev_id)
>> {
>> struct stm32_rtc *rtc = (struct stm32_rtc *)dev_id;
>> - unsigned int isr, cr;
>> + struct stm32_rtc_registers regs = rtc->data->regs;
>> + struct stm32_rtc_events evts = rtc->data->events;
>
> Ditto for evts.
>

I prepare a v3 with const struct stm32_rtc_registers *regs and const
struct stm32_rtc_events *evts.

>> + unsigned int status, cr;
>>
>> mutex_lock(&rtc->rtc_dev->ops_lock);
>>
>> - isr = readl_relaxed(rtc->base + STM32_RTC_ISR);
>> - cr = readl_relaxed(rtc->base + STM32_RTC_CR);
>> + status = readl_relaxed(rtc->base + regs.isr);
>> + cr = readl_relaxed(rtc->base + regs.cr);
>>
>> - if ((isr & STM32_RTC_ISR_ALRAF) &&
>> + if ((status & evts.alra) &&
>> (cr & STM32_RTC_CR_ALRAIE)) {
>> /* Alarm A flag - Alarm interrupt */
>> dev_dbg(&rtc->rtc_dev->dev, "Alarm occurred\n");
>
> ...
>
>> @@ -641,7 +710,7 @@ static int stm32_rtc_probe(struct platform_device *pdev)
>>
>> /*
>> * After a system reset, RTC_ISR.INITS flag can be read to check if
>> - * the calendar has been initalized or not. INITS flag is reset by a
>> + * the calendar has been initialized or not. INITS flag is reset by a
>> * power-on reset (no vbat, no power-supply). It is not reset if
>> * rtc_ck parent clock has changed (so RTC prescalers need to be
>> * changed). That's why we cannot rely on this flag to know if RTC
>> @@ -666,7 +735,7 @@ static int stm32_rtc_probe(struct platform_device *pdev)
>> "alarm won't be able to wake up the system");
>>
>> rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name,
>> - &stm32_rtc_ops, THIS_MODULE);
>> + &stm32_rtc_ops, THIS_MODULE);
>> if (IS_ERR(rtc->rtc_dev)) {
>> ret = PTR_ERR(rtc->rtc_dev);
>> dev_err(&pdev->dev, "rtc device registration failed, err=%d\n",
>
> Those two changes should go into a separate cleanup patch.
>

OK, new patch for these two changes in v3.

Thanks for reviewing,
Amelie