drivers/mtd/spi/spi_flash.c

   1 /*
   2  * SPI flash interface
   3  *
   4  * Copyright (C) 2008 Atmel Corporation
   5  * Copyright (C) 2010 Reinhard Meyer, EMK Elektronik
   6  *
   7  * Licensed under the GPL-2 or later.
   8  */
   9
  10 #include <common.h>
  11 #include <spi.h>
  12
  13 static int spi_flash_read_write(struct spi_slave *spi,
  14                                 const u8 *cmd, size_t cmd_len,
  15                                 const u8 *data_out, u8 *data_in,
  16                                 size_t data_len)
  17 {
  18         unsigned long flags = SPI_XFER_BEGIN;
  19         int ret;
  20
  21         if (data_len == 0)
  22                 flags |= SPI_XFER_END;
  23
  24         ret = spi_xfer(spi, cmd_len * 8, cmd, NULL, flags);
  25         if (ret) {
  26                 debug("SF: Failed to send command (%zu bytes): %d\n",
  27                       cmd_len, ret);
  28         } else if (data_len != 0) {
  29                 ret = spi_xfer(spi, data_len * 8, data_out, data_in,
  30                                         SPI_XFER_END);
  31                 if (ret)
  32                         debug("SF: Failed to transfer %zu bytes of data: %d\n",
  33                               data_len, ret);
  34         }
  35
  36         return ret;
  37 }
  38
  39 int spi_flash_cmd_read(struct spi_slave *spi, const u8 *cmd,
  40                 size_t cmd_len, void *data, size_t data_len)
  41 {
  42         return spi_flash_read_write(spi, cmd, cmd_len, NULL, data, data_len);
  43 }
  44
  45 int spi_flash_cmd(struct spi_slave *spi, u8 cmd, void *response, size_t len)
  46 {
  47         return spi_flash_cmd_read(spi, &cmd, 1, response, len);
  48 }
  49
  50 int spi_flash_cmd_write(struct spi_slave *spi, const u8 *cmd, size_t cmd_len,
  51                 const void *data, size_t data_len)
  52 {
  53         return spi_flash_read_write(spi, cmd, cmd_len, data, NULL, data_len);
  54 }