mmc: tmio: support IP-builtin card detection logic

A card detect GPIO is set up only for platforms with "cd-gpios"
DT property or TMIO_MMC_USE_GPIO_CD flag.  However, the driver
core always uses mmc_gpio_get_cd, which just fails with -ENOSYS
if ctx->cd_gpio is unset.

The bit 5 of the status register provides the current signal level
of the CD line.  Allow to use it if the GPIO is unused.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c
index f5da8bb..2abc425 100644 (file)
--- a/drivers/mmc/host/tmio_mmc_core.c
+++ b/drivers/mmc/host/tmio_mmc_core.c
@@ -1066,6 +1066,14 @@ static int tmio_mmc_get_ro(struct mmc_host *mmc)
                 TMIO_STAT_WRPROTECT);
 }
 
+static int tmio_mmc_get_cd(struct mmc_host *mmc)
+{
+       struct tmio_mmc_host *host = mmc_priv(mmc);
+
+       return !!(sd_ctrl_read16_and_16_as_32(host, CTL_STATUS) &
+                 TMIO_STAT_SIGSTATE);
+}
+
 static int tmio_multi_io_quirk(struct mmc_card *card,
                               unsigned int direction, int blk_size)
 {
@@ -1081,7 +1089,7 @@ static const struct mmc_host_ops tmio_mmc_ops = {
        .request        = tmio_mmc_request,
        .set_ios        = tmio_mmc_set_ios,
        .get_ro         = tmio_mmc_get_ro,
-       .get_cd         = mmc_gpio_get_cd,
+       .get_cd         = tmio_mmc_get_cd,
        .enable_sdio_irq = tmio_mmc_enable_sdio_irq,
        .multi_io_quirk = tmio_multi_io_quirk,
        .hw_reset       = tmio_mmc_hw_reset,
@@ -1234,6 +1242,9 @@ int tmio_mmc_host_probe(struct tmio_mmc_host *_host)
        if (mmc_can_gpio_ro(mmc))
                _host->ops.get_ro = mmc_gpio_get_ro;
 
+       if (mmc_can_gpio_cd(mmc))
+               _host->ops.get_cd = mmc_gpio_get_cd;
+
        _host->native_hotplug = !(mmc_can_gpio_cd(mmc) ||
                                  mmc->caps & MMC_CAP_NEEDS_POLL ||
                                  !mmc_card_is_removable(mmc));