Re: [RESEND PATCH] mmc: sdhci: fix wakeup configuration

From: Ludovic Desroches
Date: Fri May 13 2016 - 09:17:15 EST


Mistake while sending v2, sorry for the noise.

On Fri, May 13, 2016 at 03:14:46PM +0200, Ludovic Desroches wrote:
> Activating wakeup event is not enough to get a wakeup signal. The
> corresponding events have to be enabled in the Interrupt Status Enable
> Register too.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
> ---
> Hi,
>
> I just updated sdhci_enable_irq_wakeups() not sdhci_disable_irq_wakeups()
> because I don't think it is necessary to configure SDHCI_INT_ENABLE at this
> step, it will be done with sdhci_init() or sdhci_enable_card_detection().
>
> While I was writing this patch, several questions came to my mind:
> - Is the naming correct? wakeup signal is not an irq. 'enable_irq_wakeups' can
> be a bit confusing.
> - If we want to wakeup from irq, we may have to set SDHCI_INT_ENABLE and
> SDHCI_SIGNAL_ENABLE and not rely on a previous configuration, isn't it?
>
> Regards
>
> Ludovic
>
> drivers/mmc/host/sdhci.c | 26 ++++++++++++++++++--------
> 1 file changed, 18 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index b284924..6fc69ed 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -2638,18 +2638,28 @@ static irqreturn_t sdhci_thread_irq(int irq, void *dev_id)
> \*****************************************************************************/
>
> #ifdef CONFIG_PM
> +/*
> + * To enable wakeup events, the corresponding events have to be enabled in
> + * the Interrupt Status Enable register too. See 'Table 1-6: Wakeup Signal
> + * Table' in the SD Host Controller Standard Specification.
> + */
> void sdhci_enable_irq_wakeups(struct sdhci_host *host)
> {
> - u8 val;
> - u8 mask = SDHCI_WAKE_ON_INSERT | SDHCI_WAKE_ON_REMOVE
> - | SDHCI_WAKE_ON_INT;
> + u8 wakeup_val;
> + u8 wakeup_mask = SDHCI_WAKE_ON_INSERT | SDHCI_WAKE_ON_REMOVE |
> + SDHCI_WAKE_ON_INT;
> + u32 irq_val = SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE |
> + SDHCI_INT_CARD_INT;
>
> - val = sdhci_readb(host, SDHCI_WAKE_UP_CONTROL);
> - val |= mask ;
> + wakeup_val = sdhci_readb(host, SDHCI_WAKE_UP_CONTROL);
> + wakeup_val |= wakeup_mask;
> /* Avoid fake wake up */
> - if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
> - val &= ~(SDHCI_WAKE_ON_INSERT | SDHCI_WAKE_ON_REMOVE);
> - sdhci_writeb(host, val, SDHCI_WAKE_UP_CONTROL);
> + if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) {
> + wakeup_val &= ~(SDHCI_WAKE_ON_INSERT | SDHCI_WAKE_ON_REMOVE);
> + irq_val &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);
> + }
> + sdhci_writeb(host, wakeup_val, SDHCI_WAKE_UP_CONTROL);
> + sdhci_writel(host, irq_val, SDHCI_INT_ENABLE);
> }
> EXPORT_SYMBOL_GPL(sdhci_enable_irq_wakeups);
>
> --
> 2.5.0
>