mmc_spi: Add support for OpenFirmware bindings
authorAnton Vorontsov <avorontsov@ru.mvista.com>
Tue, 30 Dec 2008 15:15:28 +0000 (18:15 +0300)
committerPierre Ossman <drzeus@drzeus.cx>
Wed, 31 Dec 2008 18:01:55 +0000 (19:01 +0100)
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>
drivers/mmc/host/Makefile
drivers/mmc/host/mmc_spi.c
drivers/mmc/host/of_mmc_spi.c [new file with mode: 0644]
include/linux/spi/mmc_spi.h

index c794cc5..f485328 100644 (file)
@@ -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
index ad00e16..87e211d 100644 (file)
@@ -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 (file)
index 0000000..fb2921f
--- /dev/null
@@ -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);
index a3626ae..0f4eb16 100644 (file)
@@ -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 */