Re: [PATCH] mmc: sdhci-esdhc-imx: Enable/Disable mmc clock during runtime suspend
From: Michael Nazzareno Trimarchi <michael@amarulasolutions.com>
Date: 2018-01-03 17:26:36
Hi Ulf
I have still a small question because I'm changing this driver:
We have in sdhci_pxav3_runtime_suspend
ret = sdhci_runtime_suspend_host(host);
if (ret)
return ret;
clk_disable_unprepare(pxa->clk_io);
if (!IS_ERR(pxa->clk_core))
clk_disable_unprepare(pxa->clk_core);
and in the other driver like this one
ret = sdhci_runtime_suspend_host(host);
if (!sdhci_sdio_irq_enabled(host)) {
imx_data->actual_clock = host->mmc->actual_clock;
esdhc_pltfm_set_clock(host, 0);
clk_disable_unprepare(imx_data->clk_per);
clk_disable_unprepare(imx_data->clk_ipg);
}
clk_disable_unprepare(imx_data->clk_ahb);
Now to be more funny we have
int sdhci_runtime_suspend_host(struct sdhci_host *host)
{
unsigned long flags;
mmc_retune_timer_stop(host->mmc);
if (host->tuning_mode != SDHCI_TUNING_MODE_3)
mmc_retune_needed(host->mmc);
spin_lock_irqsave(&host->lock, flags);
host->ier &= SDHCI_INT_CARD_INT;
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
spin_unlock_irqrestore(&host->lock, flags);
synchronize_hardirq(host->irq);
spin_lock_irqsave(&host->lock, flags);
host->runtime_suspended = true;
spin_unlock_irqrestore(&host->lock, flags);
return 0;
}
Anyway. What we need to do with the clock in general if we have a fail before?
Michael
On Wed, Jan 3, 2018 at 5:58 PM, Michael Nazzareno Trimarchi
[off-list ref] wrote:Hi On Wed, Jan 3, 2018 at 5:56 PM, Ulf Hansson [off-list ref] wrote:quoted
On 3 January 2018 at 17:38, Michael Nazzareno Trimarchi [off-list ref] wrote:quoted
Hi On Wed, Jan 3, 2018 at 5:26 PM, Ulf Hansson [off-list ref] wrote:quoted
On 21 December 2017 at 14:22, Michael Trimarchi [off-list ref] wrote:quoted
mmc clock can be stopped during runtime suspend and restart during runtime resume. This let us know to not have any clock running and this reduce the EMI of the device when the bus is not in use Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com> --- drivers/mmc/host/sdhci-esdhc-imx.c | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index 7123ef9..9a5e96f 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c@@ -196,6 +196,7 @@ struct pltfm_imx_data { struct clk *clk_ipg; struct clk *clk_ahb; struct clk *clk_per; + unsigned int actual_clock; enum { NO_CMD_PENDING, /* no multiblock command pending*/ MULTIBLK_IN_PROCESS, /* exact multiblock cmd in process */@@ -1346,6 +1347,9 @@ static int sdhci_esdhc_runtime_suspend(struct device *dev) ret = sdhci_runtime_suspend_host(host); + imx_data->actual_clock = host->mmc->actual_clock; + esdhc_pltfm_set_clock(host, 0);I guess want the clock to stay on "if sdhci_sdio_irq_enabled(host)". So you should probably move the above inside the below if statement.Well I'm not quite sure about it. Some wifi chipset has the wakeup interrupt on external gpio and someone wakeup from DAT1. Why clock should be required?The clock should not be needed when using external GPIO (also described as an out-band IRQ/wakeup), but from DAT1.Ok, I will re-post new patchesquoted
When sdhci_sdio_irq_enabled() returns true, that *should* indicate that DAT1 is used. Although, there may be reasons to re-visit this later, because the hole SDIO irq thing around wakeups for sdhci, is being reworked by Adrian [1].I will take a look on this post Regards Michaelquoted
quoted
Anyway I should even rebalance resume.Yes. [...] Kind regards Uffe [1] https://www.spinics.net/lists/linux-mmc/msg47512.html
-- | Michael Nazzareno Trimarchi Amarula Solutions BV | | COO - Founder Cruquiuskade 47 | | +31(0)851119172 Amsterdam 1018 AM NL | | [`as] http://www.amarulasolutions.com |