mmc: sunxi: avoid invalid pointer calculation

commit d34712d2e3db9b241d0484a6e3839c6b7ef9df78 upstream.

The sunxi mmc driver tries to calculate a dma address by using pointer
arithmetic, which causes a warning when dma_addr_t is wider than a pointer:

drivers/mmc/host/sunxi-mmc.c: In function 'sunxi_mmc_init_idma_des':
drivers/mmc/host/sunxi-mmc.c:296:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
  struct sunxi_idma_des *pdes_pa = (struct sunxi_idma_des *)host->sg_dma;
                                   ^

To avoid this warning and to simplify the logic, this changes
the code to avoid the cast and calculate the correct address
manually. The behavior should be unchanged.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David Lanzendörfer <david.lanzendoerfer@o2s.ch>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index aac659bdd08ab2f9eb0603306d466958cc24ed8f..99a84250533c02b230945d7ff665543e0ad91eaf 100644 (file)
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -294,7 +294,7 @@ static void sunxi_mmc_init_idma_des(struct sunxi_mmc_host *host,
                                    struct mmc_data *data)
 {
        struct sunxi_idma_des *pdes = (struct sunxi_idma_des *)host->sg_cpu;
-       struct sunxi_idma_des *pdes_pa = (struct sunxi_idma_des *)host->sg_dma;
+       dma_addr_t next_desc = host->sg_dma;
        int i, max_len = (1 << host->idma_des_size_bits);
 
        for (i = 0; i < data->sg_len; i++) {
@@ -306,8 +306,9 @@ static void sunxi_mmc_init_idma_des(struct sunxi_mmc_host *host,
                else
                        pdes[i].buf_size = data->sg[i].length;
 
+               next_desc += sizeof(struct sunxi_idma_des);
                pdes[i].buf_addr_ptr1 = sg_dma_address(&data->sg[i]);
-               pdes[i].buf_addr_ptr2 = (u32)&pdes_pa[i + 1];
+               pdes[i].buf_addr_ptr2 = (u32)next_desc;
        }
 
        pdes[0].config |= SDXC_IDMAC_DES0_FD;