mmc: mmc_spi: Support CD/RO GPIOs

Add support for passing CD/RO GPIO numbers directly to the mmc_spi
driver instead of relying solely on board code callbacks to retrieve the
CD/RO signals values. The driver will enable debouncing on the card
detect GPIO if the cd_debounce field is set to a non-zero value.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 74145d1..62fb82d 100644 (file)
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -36,6 +36,7 @@
 
 #include <linux/mmc/host.h>
 #include <linux/mmc/mmc.h>             /* for R1_SPI_* bit values */
+#include <linux/mmc/slot-gpio.h>
 
 #include <linux/spi/spi.h>
 #include <linux/spi/mmc_spi.h>
@@ -1278,11 +1279,8 @@ static int mmc_spi_get_ro(struct mmc_host *mmc)
 
        if (host->pdata && host->pdata->get_ro)
                return !!host->pdata->get_ro(mmc->parent);
-       /*
-        * Board doesn't support read only detection; let the mmc core
-        * decide what to do.
-        */
-       return -ENOSYS;
+       else
+               return mmc_gpio_get_ro(mmc);
 }
 
 static int mmc_spi_get_cd(struct mmc_host *mmc)
@@ -1291,7 +1289,8 @@ static int mmc_spi_get_cd(struct mmc_host *mmc)
 
        if (host->pdata && host->pdata->get_cd)
                return !!host->pdata->get_cd(mmc->parent);
-       return -ENOSYS;
+       else
+               return mmc_gpio_get_cd(mmc);
 }
 
 static const struct mmc_host_ops mmc_spi_ops = {
@@ -1324,6 +1323,7 @@ static int mmc_spi_probe(struct spi_device *spi)
        struct mmc_host         *mmc;
        struct mmc_spi_host     *host;
        int                     status;
+       bool                    has_ro = false;
 
        /* We rely on full duplex transfers, mostly to reduce
         * per-transfer overheads (by making fewer transfers).
@@ -1448,18 +1448,33 @@ static int mmc_spi_probe(struct spi_device *spi)
        }
 
        /* pass platform capabilities, if any */
-       if (host->pdata)
+       if (host->pdata) {
                mmc->caps |= host->pdata->caps;
+               mmc->caps2 |= host->pdata->caps2;
+       }
 
        status = mmc_add_host(mmc);
        if (status != 0)
                goto fail_add_host;
 
+       if (host->pdata && host->pdata->flags & MMC_SPI_USE_CD_GPIO) {
+               status = mmc_gpio_request_cd(mmc, host->pdata->cd_gpio,
+                                            host->pdata->cd_debounce);
+               if (status != 0)
+                       goto fail_add_host;
+       }
+
+       if (host->pdata && host->pdata->flags & MMC_SPI_USE_RO_GPIO) {
+               has_ro = true;
+               status = mmc_gpio_request_ro(mmc, host->pdata->ro_gpio);
+               if (status != 0)
+                       goto fail_add_host;
+       }
+
        dev_info(&spi->dev, "SD/MMC host %s%s%s%s%s\n",
                        dev_name(&mmc->class_dev),
                        host->dma_dev ? "" : ", no DMA",
-                       (host->pdata && host->pdata->get_ro)
-                               ? "" : ", no WP",
+                       has_ro ? "" : ", no WP",
                        (host->pdata && host->pdata->setpower)
                                ? "" : ", no poweroff",
                        (mmc->caps & MMC_CAP_NEEDS_POLL)

diff --git a/drivers/mmc/host/of_mmc_spi.c b/drivers/mmc/host/of_mmc_spi.c
index d720b5e..6e218fb 100644 (file)
--- a/drivers/mmc/host/of_mmc_spi.c
+++ b/drivers/mmc/host/of_mmc_spi.c
@@ -50,25 +50,6 @@ static struct of_mmc_spi *to_of_mmc_spi(struct device *dev)
        return container_of(dev->platform_data, struct of_mmc_spi, pdata);
 }
 
-static int of_mmc_spi_read_gpio(struct device *dev, int gpio_num)
-{
-       struct of_mmc_spi *oms = to_of_mmc_spi(dev);
-       bool active_low = oms->alow_gpios[gpio_num];
-       bool value = gpio_get_value(oms->gpios[gpio_num]);
-
-       return active_low ^ value;
-}
-
-static int of_mmc_spi_get_cd(struct device *dev)
-{
-       return of_mmc_spi_read_gpio(dev, CD_GPIO);
-}
-
-static int of_mmc_spi_get_ro(struct device *dev)
-{
-       return of_mmc_spi_read_gpio(dev, WP_GPIO);
-}
-
 static int of_mmc_spi_init(struct device *dev,
                           irqreturn_t (*irqhandler)(int, void *), void *mmc)
 {
@@ -130,20 +111,22 @@ struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi)
                if (!gpio_is_valid(oms->gpios[i]))
                        continue;
 
-               ret = gpio_request(oms->gpios[i], dev_name(dev));
-               if (ret < 0) {
-                       oms->gpios[i] = -EINVAL;
-                       continue;
-               }
-
                if (gpio_flags & OF_GPIO_ACTIVE_LOW)
                        oms->alow_gpios[i] = true;
        }
 
-       if (gpio_is_valid(oms->gpios[CD_GPIO]))
-               oms->pdata.get_cd = of_mmc_spi_get_cd;
-       if (gpio_is_valid(oms->gpios[WP_GPIO]))
-               oms->pdata.get_ro = of_mmc_spi_get_ro;
+       if (gpio_is_valid(oms->gpios[CD_GPIO])) {
+               oms->pdata.cd_gpio = oms->gpios[CD_GPIO];
+               oms->pdata.flags |= MMC_SPI_USE_CD_GPIO;
+               if (!oms->alow_gpios[CD_GPIO])
+                       oms->pdata.caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;
+       }
+       if (gpio_is_valid(oms->gpios[WP_GPIO])) {
+               oms->pdata.ro_gpio = oms->gpios[WP_GPIO];
+               oms->pdata.flags |= MMC_SPI_USE_RO_GPIO;
+               if (!oms->alow_gpios[WP_GPIO])
+                       oms->pdata.caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
+       }
 
        oms->detect_irq = irq_of_parse_and_map(np, 0);
        if (oms->detect_irq != 0) {
@@ -166,15 +149,10 @@ void mmc_spi_put_pdata(struct spi_device *spi)
        struct device *dev = &spi->dev;
        struct device_node *np = dev->of_node;
        struct of_mmc_spi *oms = to_of_mmc_spi(dev);
-       int i;
 
        if (!dev->platform_data || !np)
                return;
 
-       for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) {
-               if (gpio_is_valid(oms->gpios[i]))
-                       gpio_free(oms->gpios[i]);
-       }
        kfree(oms);
        dev->platform_data = NULL;
 }

diff --git a/include/linux/spi/mmc_spi.h b/include/linux/spi/mmc_spi.h
index 32be8db..87cdb35 100644 (file)
--- a/include/linux/spi/mmc_spi.h
+++ b/include/linux/spi/mmc_spi.h
@@ -7,6 +7,11 @@
 struct device;
 struct mmc_host;
 
+#define MMC_SPI_USE_CD_GPIO                    (1 << 0)
+#define MMC_SPI_USE_RO_GPIO                    (1 << 1)
+#define MMC_SPI_CD_GPIO_ACTIVE_LOW             (1 << 2)
+#define MMC_SPI_RO_GPIO_ACTIVE_LOW             (1 << 3)
+
 /* Put this in platform_data of a device being used to manage an MMC/SD
  * card slot.  (Modeled after PXA mmc glue; see that for usage examples.)
  *
@@ -30,8 +35,19 @@ struct mmc_spi_platform_data {
         */
        int (*get_cd)(struct device *);
 
+       /*
+        * Card Detect and Read Only GPIOs. To enable debouncing on the card
+        * detect GPIO, set the cd_debounce to the debounce time in
+        * microseconds.
+        */
+       unsigned int flags;
+       unsigned int cd_gpio;
+       unsigned int cd_debounce;
+       unsigned int ro_gpio;
+
        /* Capabilities to pass into mmc core (e.g. MMC_CAP_NEEDS_POLL). */
        unsigned long caps;
+       unsigned long caps2;
 
        /* how long to debounce card detect, in msecs */
        u16 detect_delay;