Re: [RFC PATCH 2/4] mmc: sdio: bind sdio device with acpi device

Rafael J. Wysocki
2012-10-18T23:25:46Z

On Friday 12 of October 2012 11:12:39 Aaron Lu wrote:
> ACPI spec defines the _ADDR encoding for sdio bus as:
> High word - slot number (0 based)
> Low word - function number
>
> This patch adds support for sdio device binding with acpi using the
> generic ACPI glue framework.
>
> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> ---
> drivers/mmc/core/Makefile | 1 +
> drivers/mmc/core/sdio_acpi.c | 35 +++++++++++++++++++++++++++++++++++
> drivers/mmc/core/sdio_bus.c | 14 ++++++++++++--
> drivers/mmc/core/sdio_bus.h | 2 ++
> 4 files changed, 50 insertions(+), 2 deletions(-)
> create mode 100644 drivers/mmc/core/sdio_acpi.c
>
> diff --git a/drivers/mmc/core/Makefile b/drivers/mmc/core/Makefile
> index 38ed210..c8300aa 100644
> --- a/drivers/mmc/core/Makefile
> +++ b/drivers/mmc/core/Makefile
> @@ -10,3 +10,4 @@ mmc_core-y := core.o bus.o host.o \
> quirks.o slot-gpio.o
>
> mmc_core-$(CONFIG_DEBUG_FS) += debugfs.o
> +mmc_core-$(CONFIG_ACPI) += sdio_acpi.o
> diff --git a/drivers/mmc/core/sdio_acpi.c b/drivers/mmc/core/sdio_acpi.c
> new file mode 100644
> index 0000000..0f92e90
> --- /dev/null
> +++ b/drivers/mmc/core/sdio_acpi.c
> @@ -0,0 +1,35 @@
> +#include <linux/mmc/host.h>
> +#include <linux/mmc/card.h>
> +#include <linux/mmc/sdhci.h>
> +#include <linux/mmc/sdio_func.h>
> +#include <linux/acpi.h>
> +#include <acpi/acpi_bus.h>
> +#include "sdio_bus.h"
> +
> +static int acpi_sdio_find_device(struct device *dev, acpi_handle *handle)
> +{
> + struct sdio_func *func;
> + struct sdhci_host *host;
> + u64 addr;
> +
> + func = dev_to_sdio_func(dev);
> + host = mmc_priv(func->card->host);
> +
> + addr = (host->slotno << 16) | func->num;
> +
> + *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev), addr);
> + if (!*handle)
> + return -ENODEV;
> +
> + return 0;
> +}
> +
> +static struct acpi_bus_type acpi_sdio_bus = {
> + .bus = &sdio_bus_type,
> + .find_device = acpi_sdio_find_device,
> +};
> +
> +int sdio_acpi_register(void)

I'd call it sdio_acpi_register_bus().

> +{
> + return register_acpi_bus_type(&acpi_sdio_bus);
> +}
> diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
> index 6bf6879..aaec9e2 100644
> --- a/drivers/mmc/core/sdio_bus.c
> +++ b/drivers/mmc/core/sdio_bus.c
> @@ -23,6 +23,7 @@
>
> #include "sdio_cis.h"
> #include "sdio_bus.h"
> +#include "sdio_acpi.h"
>
> /* show configuration fields */
> #define sdio_config_attr(field, format_string) \
> @@ -209,7 +210,7 @@ static const struct dev_pm_ops sdio_bus_pm_ops = {
>
> #endif /* !CONFIG_PM */
>
> -static struct bus_type sdio_bus_type = {
> +struct bus_type sdio_bus_type = {
> .name = "sdio",
> .dev_attrs = sdio_dev_attrs,
> .match = sdio_bus_match,
> @@ -221,7 +222,16 @@ static struct bus_type sdio_bus_type = {
>
> int sdio_register_bus(void)
> {
> - return bus_register(&sdio_bus_type);
> + int ret;
> +
> + ret = bus_register(&sdio_bus_type);
> + if (ret)
> + goto out;
> +
> + ret = sdio_acpi_register();

What happens if this fails?

> +
> +out:
> + return ret;
> }
>
> void sdio_unregister_bus(void)
> diff --git a/drivers/mmc/core/sdio_bus.h b/drivers/mmc/core/sdio_bus.h
> index 567a768..91c0e93 100644
> --- a/drivers/mmc/core/sdio_bus.h
> +++ b/drivers/mmc/core/sdio_bus.h
> @@ -18,5 +18,7 @@ void sdio_remove_func(struct sdio_func *func);
> int sdio_register_bus(void);
> void sdio_unregister_bus(void);
>
> +extern struct bus_type sdio_bus_type;
> +
> #endif

Thanks,
Rafael

--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.