}
EXPORT_SYMBOL_GPL(sdio_readb);
+/**
+ * sdio_readb_ext - read a single byte from a SDIO function
+ * @func: SDIO function to access
+ * @addr: address to read
+ * @err_ret: optional status value from transfer
+ * @in: value to add to argument
+ *
+ * Reads a single byte from the address space of a given SDIO
+ * function. If there is a problem reading the address, 0xff
+ * is returned and @err_ret will contain the error code.
+ */
+unsigned char sdio_readb_ext(struct sdio_func *func, unsigned int addr,
+ int *err_ret, unsigned in)
+{
+ int ret;
+ unsigned char val;
+
+ BUG_ON(!func);
+
+ if (err_ret)
+ *err_ret = 0;
+
+ ret = mmc_io_rw_direct(func->card, 0, func->num, addr, (u8)in, &val);
+ if (ret) {
+ if (err_ret)
+ *err_ret = ret;
+ return 0xFF;
+ }
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(sdio_readb_ext);
+
/**
* sdio_writeb - write a single byte to a SDIO function
* @func: SDIO function to access
extern unsigned int sdio_align_size(struct sdio_func *func, unsigned int sz);
extern u8 sdio_readb(struct sdio_func *func, unsigned int addr, int *err_ret);
+extern u8 sdio_readb_ext(struct sdio_func *func, unsigned int addr, int *err_ret,
+ unsigned in);
extern u16 sdio_readw(struct sdio_func *func, unsigned int addr, int *err_ret);
extern u32 sdio_readl(struct sdio_func *func, unsigned int addr, int *err_ret);