On 22/11/16 23:53, Zach Brown wrote:
> On NI 9037 boards the max SDIO frequency is limited by trace lengths
> and other layout choices. The max SDIO frequency is stored in an ACPI
> table.
>
> The driver reads the ACPI entry MXFQ during sdio_probe_slot and sets the
> f_max field of the host.
>
> Signed-off-by: Nathan Sullivan <nathan.sulli...@ni.com>
> Reviewed-by: Jaeden Amero <jaeden.am...@ni.com>
> Reviewed-by: Josh Cartwright <jo...@ni.com>
> Signed-off-by: Zach Brown <zach.br...@ni.com>
> ---
> drivers/mmc/host/sdhci-pci-core.c | 28 ++++++++++++++++++++++++++++
> 1 file changed, 28 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-pci-core.c
> b/drivers/mmc/host/sdhci-pci-core.c
> index 9741505..34284b8 100644
> --- a/drivers/mmc/host/sdhci-pci-core.c
> +++ b/drivers/mmc/host/sdhci-pci-core.c
> @@ -27,6 +27,7 @@
> #include <linux/pm_runtime.h>
> #include <linux/mmc/slot-gpio.h>
> #include <linux/mmc/sdhci-pci-data.h>
> +#include <linux/acpi.h>
>
> #include "sdhci.h"
> #include "sdhci-pci.h"
> @@ -375,6 +376,30 @@ static int byt_emmc_probe_slot(struct sdhci_pci_slot
> *slot)
> return 0;
> }
>
> +#ifdef CONFIG_ACPI
> +
> +static int ni_byt_sdio_probe_slot(struct sdhci_pci_slot *slot)
> +{
> + acpi_status status;
> + unsigned long long max_freq;
> +
> + status = acpi_evaluate_integer(ACPI_HANDLE(&slot->chip->pdev->dev),
> + "MXFQ", NULL, &max_freq);
> + if (ACPI_FAILURE(status)) {
> + dev_err(&slot->chip->pdev->dev,
> + "MXFQ not found in acpi table\n");
> + return -EINVAL;
> + }
> +
> + slot->host->mmc->f_max = max_freq * 1000000;
> +
> + slot->host->mmc->caps |= MMC_CAP_POWER_OFF_CARD | MMC_CAP_NONREMOVABLE |
> + MMC_CAP_WAIT_WHILE_BUSY;
> + return 0;
> +}
> +
> +#else
No, it is the ACPI access that needs to be a separate function. We don't
want 2 ni_byt_sdio_probe_slot(). Perhaps, something like:
#ifdef CONFIG_ACPI
static int ni_set_max_freq(struct sdhci_pci_slot *slot)
{
acpi_status status;
unsigned long long max_freq;
status = acpi_evaluate_integer(ACPI_HANDLE(&slot->chip->pdev->dev),
"MXFQ", NULL, &max_freq);
if (ACPI_FAILURE(status))
dev_err(&slot->chip->pdev->dev,
"MXFQ not found in acpi table\n");
return -EINVAL;
}
slot->host->mmc->f_max = max_freq * 1000000;
return 0;
}
#else
static inline int ni_set_max_freq(struct sdhci_pci_slot *slot)
{
return 0;
}
#endif
