spi: fsl_qspi: Fix qspi_op_rdid memcpy issue

In current driver everytime we memcpy 4 bytes to the dest memory
regardless of the remaining length.
This patch adds checking the remaining length before memcpy.
If the length is shorter than 4 bytes, memcpy the actual length of data
to the dest memory.

Signed-off-by: Gong Qianyu <Qianyu.Gong@freescale.com>
Reviewed-by: York Sun <york.sun@nxp.com>

diff --git a/drivers/spi/fsl_qspi.c b/drivers/spi/fsl_qspi.c
index 38e5900dba84186cff95a03b387a169f690d357e..3553e0038fad8a35900437ad44b13106a31d0305 100644 (file)
--- a/drivers/spi/fsl_qspi.c
+++ b/drivers/spi/fsl_qspi.c
@@ -477,8 +477,8 @@ static void qspi_op_rdbank(struct fsl_qspi_priv *priv, u8 *rxbuf, u32 len)
 static void qspi_op_rdid(struct fsl_qspi_priv *priv, u32 *rxbuf, u32 len)
 {
        struct fsl_qspi_regs *regs = priv->regs;
-       u32 mcr_reg, rbsr_reg, data;
-       int i, size;
+       u32 mcr_reg, rbsr_reg, data, size;
+       int i;
 
        mcr_reg = qspi_read32(priv->flags, &regs->mcr);
        qspi_write32(priv->flags, &regs->mcr,
@@ -494,15 +494,15 @@ static void qspi_op_rdid(struct fsl_qspi_priv *priv, u32 *rxbuf, u32 len)
                ;
 
        i = 0;
-       size = len;
-       while ((RX_BUFFER_SIZE >= size) && (size > 0)) {
+       while ((RX_BUFFER_SIZE >= len) && (len > 0)) {
                rbsr_reg = qspi_read32(priv->flags, &regs->rbsr);
                if (rbsr_reg & QSPI_RBSR_RDBFL_MASK) {
                        data = qspi_read32(priv->flags, &regs->rbdr[i]);
                        data = qspi_endian_xchg(data);
-                       memcpy(rxbuf, &data, 4);
+                       size = (len < 4) ? len : 4;
+                       memcpy(rxbuf, &data, size);
+                       len -= size;
                        rxbuf++;
-                       size -= 4;
                        i++;
                }
        }