x86: ich-spi: Fix a bug of reading from a non-64 bytes aligned address

The ich spi controller driver spi_xfer() tries to align reading
address to 64 bytes when doing spi data in, which causes a bug of
either infinite loop or a huge size memcpy().

Actually the ich spi controller does not have such requirement of
64 bytes alignment when reading data from spi slave devices.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/spi/ich.c b/drivers/spi/ich.c
index f5c6f3e7d29071704cd8baa541f88808d5cbfabb..c4d3a291e8dbf75cbbb52ba0ab3c8efe704678ac 100644 (file)
--- a/drivers/spi/ich.c
+++ b/drivers/spi/ich.c
@@ -483,8 +483,6 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
        struct spi_trans *trans = &ich->trans;
        unsigned type = flags & (SPI_XFER_BEGIN | SPI_XFER_END);
        int using_cmd = 0;
-       /* Align read transactions to 64-byte boundaries */
-       char buff[ctlr.databytes];
 
        /* Ee don't support writing partial bytes. */
        if (bitlen % 8) {
@@ -632,14 +630,9 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
         */
        while (trans->bytesout || trans->bytesin) {
                uint32_t data_length;
-               uint32_t aligned_offset;
-               uint32_t diff;
-
-               aligned_offset = trans->offset & ~(ctlr.databytes - 1);
-               diff = trans->offset - aligned_offset;
 
                /* SPI addresses are 24 bit only */
-               ich_writel(aligned_offset & 0x00FFFFFF, ctlr.addr);
+               ich_writel(trans->offset & 0x00FFFFFF, ctlr.addr);
 
                if (trans->bytesout)
                        data_length = min(trans->bytesout, ctlr.databytes);
@@ -673,13 +666,7 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
                }
 
                if (trans->bytesin) {
-                       if (diff) {
-                               data_length -= diff;
-                               read_reg(ctlr.data, buff, ctlr.databytes);
-                               memcpy(trans->in, buff + diff, data_length);
-                       } else {
-                               read_reg(ctlr.data, trans->in, data_length);
-                       }
+                       read_reg(ctlr.data, trans->in, data_length);
                        spi_use_in(trans, data_length);
                        if (with_address)
                                trans->offset += data_length;