sdio: set the functions' block size

Before a driver is probed, set the function's block size to the default so the
driver is sure the block size is something sensible and it needn't explicitly
set it.

The default block size is the largest that's supported by both the card and
the host, with a maximum of 512 to ensure aribitrarily sized transfer use the
optimal (least) number of commands.

See http://lkml.org/lkml/2007/8/7/150 for reasons for the block size choice.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c
index d229020db4a2cd5852fd2063bd01702898d67a37..fcb13fb0daad3ff97700ac09cb80d9ef6fcb1e95 100644 (file)
--- a/drivers/mmc/core/sdio_bus.c
+++ b/drivers/mmc/core/sdio_bus.c
@@ -128,11 +128,20 @@ static int sdio_bus_probe(struct device *dev)
        struct sdio_driver *drv = to_sdio_driver(dev->driver);
        struct sdio_func *func = dev_to_sdio_func(dev);
        const struct sdio_device_id *id;
+       int ret;
 
        id = sdio_match_device(func, drv);
        if (!id)
                return -ENODEV;
 
+       /* Set the default block size so the driver is sure it's something
+        * sensible. */
+       sdio_claim_host(func);
+       ret = sdio_set_block_size(func, 0);
+       sdio_release_host(func);
+       if (ret)
+               return ret;
+
        return drv->probe(func, id);
 }
 

diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index d050c40cf04624b803d9fda8df3746316a13e566..1d03f12bbb38824002d90dee04533d916b0eecba 100644 (file)
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -79,7 +79,7 @@ static int cistpl_funce_func(struct sdio_func *func,
                return -EINVAL;
 
        /* TPLFE_MAX_BLK_SIZE */
-       func->blksize = buf[12] | (buf[13] << 8);
+       func->max_blksize = buf[12] | (buf[13] << 8);
 
        return 0;
 }

diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c
index ecdb77242e98f9033156435d90e57bc2258d2b03..c2bad1195e3bffa8a1045f11d5a3d65a543e2cce 100644 (file)
--- a/drivers/mmc/core/sdio_io.c
+++ b/drivers/mmc/core/sdio_io.c
@@ -140,6 +140,55 @@ err:
 }
 EXPORT_SYMBOL_GPL(sdio_disable_func);
 
+/**
+ *     sdio_set_block_size - set the block size of an SDIO function
+ *     @func: SDIO function to change
+ *     @blksz: new block size or 0 to use the default.
+ *
+ *     The default block size is the largest supported by both the function
+ *     and the host, with a maximum of 512 to ensure that arbitrarily sized
+ *     data transfer use the optimal (least) number of commands.
+ *
+ *     A driver may call this to override the default block size set by the
+ *     core. This can be used to set a block size greater than the maximum
+ *     that reported by the card; it is the driver's responsibility to ensure
+ *     it uses a value that the card supports.
+ *
+ *     Returns 0 on success, -EINVAL if the host does not support the
+ *     requested block size, or -EIO (etc.) if one of the resultant FBR block
+ *     size register writes failed.
+ *
+ */
+int sdio_set_block_size(struct sdio_func *func, unsigned blksz)
+{
+       int ret;
+
+       if (blksz > func->card->host->max_blk_size)
+               return -EINVAL;
+
+       if (blksz == 0) {
+               blksz = min(min(
+                       func->max_blksize,
+                       func->card->host->max_blk_size),
+                       512u);
+       }
+
+       ret = mmc_io_rw_direct(func->card, 1, 0,
+               SDIO_FBR_BASE(func->num) + SDIO_FBR_BLKSIZE,
+               blksz & 0xff, NULL);
+       if (ret)
+               return ret;
+       ret = mmc_io_rw_direct(func->card, 1, 0,
+               SDIO_FBR_BASE(func->num) + SDIO_FBR_BLKSIZE + 1,
+               (blksz >> 8) & 0xff, NULL);
+       if (ret)
+               return ret;
+       func->cur_blksize = blksz;
+       return 0;
+}
+
+EXPORT_SYMBOL_GPL(sdio_set_block_size);
+
 /**
  *     sdio_readb - read a single byte from a SDIO function
  *     @func: SDIO function to access

diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h
index af813fffc4acd560ac35c81ba5e481718f674e68..f05757984e8d630c24e9f6b880751472117acbe1 100644 (file)
--- a/include/linux/mmc/sdio_func.h
+++ b/include/linux/mmc/sdio_func.h
@@ -43,7 +43,8 @@ struct sdio_func {
        unsigned short          vendor;         /* vendor id */
        unsigned short          device;         /* device id */
 
-       unsigned short          blksize;        /* maximum block size */
+       unsigned                max_blksize;    /* maximum block size */
+       unsigned                cur_blksize;    /* current block size */
 
        unsigned int            state;          /* function state */
 #define SDIO_STATE_PRESENT     (1<<0)          /* present in sysfs */
@@ -111,6 +112,8 @@ extern void sdio_release_host(struct sdio_func *func);
 extern int sdio_enable_func(struct sdio_func *func);
 extern int sdio_disable_func(struct sdio_func *func);
 
+extern int sdio_set_block_size(struct sdio_func *func, unsigned blksz);
+
 extern int sdio_claim_irq(struct sdio_func *func, sdio_irq_handler_t *handler);
 extern int sdio_release_irq(struct sdio_func *func);