mmc_spi: Add support for OpenFirmware bindings

The support is implemented via platform data accessors, new module
(of_mmc_spi) will be created automatically when the driver compiles
on OpenFirmware platforms. Link-time dependency will load the module
automatically.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

4 files changed, 169 insertions, 2 deletions

diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index c794cc5ce442..f4853288bbb1 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -19,6 +19,9 @@ obj-$(CONFIG_MMC_AT91)		+= at91_mci.o
 obj-$(CONFIG_MMC_ATMELMCI)      += atmel-mci.o
 obj-$(CONFIG_MMC_TIFM_SD)       += tifm_sd.o
 obj-$(CONFIG_MMC_SPI)           += mmc_spi.o
+ifeq ($(CONFIG_OF),y)
+obj-$(CONFIG_MMC_SPI)           += of_mmc_spi.o
+endif
 obj-$(CONFIG_MMC_S3C)           += s3cmci.o
 obj-$(CONFIG_MMC_SDRICOH_CS)    += sdricoh_cs.o
 obj-$(CONFIG_MMC_TMIO)          += tmio_mmc.o
diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index ad00e1632317..87e211df68ac 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -1285,7 +1285,7 @@ static int mmc_spi_probe(struct spi_device *spi)
         /* Platform data is used to hook up things like card sensing
          * and power switching gpios.
          */
-        host->pdata = spi->dev.platform_data;
+        host->pdata = mmc_spi_get_pdata(spi);
         if (host->pdata)
                 mmc->ocr_avail = host->pdata->ocr_mask;
         if (!mmc->ocr_avail) {
@@ -1368,6 +1368,7 @@ fail_glue_init:
 
 fail_nobuf1:
         mmc_free_host(mmc);
+        mmc_spi_put_pdata(spi);
         dev_set_drvdata(&spi->dev, NULL);
 
 nomem:
@@ -1402,6 +1403,7 @@ static int __devexit mmc_spi_remove(struct spi_device *spi)
 
                 spi->max_speed_hz = mmc->f_max;
                 mmc_free_host(mmc);
+                mmc_spi_put_pdata(spi);
                 dev_set_drvdata(&spi->dev, NULL);
         }
         return 0;
diff --git a/drivers/mmc/host/of_mmc_spi.c b/drivers/mmc/host/of_mmc_spi.c
new file mode 100644
index 000000000000..fb2921f8099d
--- /dev/null
+++ b/drivers/mmc/host/of_mmc_spi.c
@@ -0,0 +1,149 @@
+/*
+ * OpenFirmware bindings for the MMC-over-SPI driver
+ *
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/mmc_spi.h>
+#include <linux/mmc/core.h>
+#include <linux/mmc/host.h>
+
+enum {
+        CD_GPIO = 0,
+        WP_GPIO,
+        NUM_GPIOS,
+};
+
+struct of_mmc_spi {
+        int gpios[NUM_GPIOS];
+        bool alow_gpios[NUM_GPIOS];
+        struct mmc_spi_platform_data pdata;
+};
+
+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);
+}
+
+struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi)
+{
+        struct device *dev = &spi->dev;
+        struct device_node *np = dev_archdata_get_node(&dev->archdata);
+        struct of_mmc_spi *oms;
+        const u32 *voltage_ranges;
+        int num_ranges;
+        int i;
+        int ret = -EINVAL;
+
+        if (dev->platform_data || !np)
+                return dev->platform_data;
+
+        oms = kzalloc(sizeof(*oms), GFP_KERNEL);
+        if (!oms)
+                return NULL;
+
+        voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
+        num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
+        if (!voltage_ranges || !num_ranges) {
+                dev_err(dev, "OF: voltage-ranges unspecified\n");
+                goto err_ocr;
+        }
+
+        for (i = 0; i < num_ranges; i++) {
+                const int j = i * 2;
+                u32 mask;
+
+                mask = mmc_vddrange_to_ocrmask(voltage_ranges[j],
+                                               voltage_ranges[j + 1]);
+                if (!mask) {
+                        ret = -EINVAL;
+                        dev_err(dev, "OF: voltage-range #%d is invalid\n", i);
+                        goto err_ocr;
+                }
+                oms->pdata.ocr_mask |= mask;
+        }
+
+        for (i = 0; i < ARRAY_SIZE(oms->gpios); i++) {
+                enum of_gpio_flags gpio_flags;
+
+                oms->gpios[i] = of_get_gpio_flags(np, i, &gpio_flags);
+                if (!gpio_is_valid(oms->gpios[i]))
+                        continue;
+
+                ret = gpio_request(oms->gpios[i], dev->bus_id);
+                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;
+
+        /* We don't support interrupts yet, let's poll. */
+        oms->pdata.caps |= MMC_CAP_NEEDS_POLL;
+
+        dev->platform_data = &oms->pdata;
+        return dev->platform_data;
+err_ocr:
+        kfree(oms);
+        return NULL;
+}
+EXPORT_SYMBOL(mmc_spi_get_pdata);
+
+void mmc_spi_put_pdata(struct spi_device *spi)
+{
+        struct device *dev = &spi->dev;
+        struct device_node *np = dev_archdata_get_node(&dev->archdata);
+        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;
+}
+EXPORT_SYMBOL(mmc_spi_put_pdata);
diff --git a/include/linux/spi/mmc_spi.h b/include/linux/spi/mmc_spi.h
index a3626aedaec9..0f4eb165f254 100644
--- a/include/linux/spi/mmc_spi.h
+++ b/include/linux/spi/mmc_spi.h
@@ -1,9 +1,10 @@
 #ifndef __LINUX_SPI_MMC_SPI_H
 #define __LINUX_SPI_MMC_SPI_H
 
+#include <linux/device.h>
+#include <linux/spi/spi.h>
 #include <linux/interrupt.h>
 
-struct device;
 struct mmc_host;
 
 /* Put this in platform_data of a device being used to manage an MMC/SD
@@ -41,4 +42,16 @@ struct mmc_spi_platform_data {
         void (*setpower)(struct device *, unsigned int maskval);
 };
 
+#ifdef CONFIG_OF
+extern struct mmc_spi_platform_data *mmc_spi_get_pdata(struct spi_device *spi);
+extern void mmc_spi_put_pdata(struct spi_device *spi);
+#else
+static inline struct mmc_spi_platform_data *
+mmc_spi_get_pdata(struct spi_device *spi)
+{
+        return spi->dev.platform_data;
+}
+static inline void mmc_spi_put_pdata(struct spi_device *spi) {}
+#endif /* CONFIG_OF */
+
 #endif /* __LINUX_SPI_MMC_SPI_H */