sf: Add spi_flash_alloc() to create a new SPI flash struct

At present it is difficult to extend the SPI flash structure since
all devices allocate it themselves, and few of them zero all fields.
Add a new function spi_flash_alloc() which can be used by SPI devices
to perform this allocation, and thus ensure that all devices can
better cope with SPI structure changes.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index 00aece9291c398f44ec4db007d7048ac8727b5a3..17f3d3cb147c1e1734a38a3fc26f95c0acc83c12 100644 (file)
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -401,6 +401,31 @@ err_claim_bus:
        return NULL;
 }
 
+void *spi_flash_do_alloc(int offset, int size, struct spi_slave *spi,
+                        const char *name)
+{
+       struct spi_flash *flash;
+       void *ptr;
+
+       ptr = malloc(size);
+       if (!ptr) {
+               debug("SF: Failed to allocate memory\n");
+               return NULL;
+       }
+       memset(ptr, '\0', size);
+       flash = (struct spi_flash *)(ptr + offset);
+
+       /* Set up some basic fields - caller will sort out sizes */
+       flash->spi = spi;
+       flash->name = name;
+
+       flash->read = spi_flash_cmd_read_fast;
+       flash->write = spi_flash_cmd_write_multi;
+       flash->erase = spi_flash_cmd_erase;
+
+       return flash;
+}
+
 void spi_flash_free(struct spi_flash *flash)
 {
        spi_free_slave(flash->spi);

diff --git a/include/spi_flash.h b/include/spi_flash.h
index 9da90624f23d665fc58c95e37da02096b1adde07..030d49cb71c1b66f95d18a65391ece2055396b39 100644 (file)
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -47,6 +47,44 @@ struct spi_flash {
                                size_t len);
 };
 
+/**
+ * spi_flash_do_alloc - Allocate a new spi flash structure
+ *
+ * The structure is allocated and cleared with default values for
+ * read, write and erase, which the caller can modify. The caller must set
+ * up size, page_size and sector_size.
+ *
+ * Use the helper macro spi_flash_alloc() to call this.
+ *
+ * @offset: Offset of struct spi_slave within slave structure
+ * @size: Size of slave structure
+ * @spi: SPI slave
+ * @name: Name of SPI flash device
+ */
+void *spi_flash_do_alloc(int offset, int size, struct spi_slave *spi,
+                        const char *name);
+
+/**
+ * spi_flash_alloc - Allocate a new SPI flash structure
+ *
+ * @_struct: Name of structure to allocate (e.g. struct ramtron_spi_fram). This
+ *     structure must contain a member 'struct spi_flash *flash'.
+ * @spi: SPI slave
+ * @name: Name of SPI flash device
+ */
+#define spi_flash_alloc(_struct, spi, name) \
+       spi_flash_do_alloc(offsetof(_struct, flash), sizeof(_struct), \
+                               spi, name)
+
+/**
+ * spi_flash_alloc_base - Allocate a new SPI flash structure with no private data
+ *
+ * @spi: SPI slave
+ * @name: Name of SPI flash device
+ */
+#define spi_flash_alloc_base(spi, name) \
+       spi_flash_do_alloc(0, sizeof(struct spi_flash), spi, name)
+
 struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
                unsigned int max_hz, unsigned int spi_mode);
 void spi_flash_free(struct spi_flash *flash);