lkml.org 
[lkml]   [2017]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v3 10/24] drm/rockchip: dw-mipi-dsi: don't assume buffer is aligned
    Date
    By dereferencing the MIPI command buffer as a u32* we rely on it being
    correctly aligned on ARM, but this may not be the case. Copy it into a
    stack variable that will be correctly aligned.

    Signed-off-by: John Keeping <john@metanate.com>
    Reviewed-by: Chris Zhong <zyw@rock-chips.com>
    ---
    v3:
    - Add Chris' Reviewed-by
    Unchanged in v2

    drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 12 +++++++-----
    1 file changed, 7 insertions(+), 5 deletions(-)

    diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
    index 03fc096fe1bd..ddbc037e7ced 100644
    --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
    +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
    @@ -607,10 +607,10 @@ static int dw_mipi_dsi_dcs_short_write(struct dw_mipi_dsi *dsi,
    static int dw_mipi_dsi_dcs_long_write(struct dw_mipi_dsi *dsi,
    const struct mipi_dsi_msg *msg)
    {
    - const u32 *tx_buf = msg->tx_buf;
    - int len = msg->tx_len, pld_data_bytes = sizeof(*tx_buf), ret;
    + const u8 *tx_buf = msg->tx_buf;
    + int len = msg->tx_len, pld_data_bytes = sizeof(u32), ret;
    u32 hdr_val = GEN_HDATA(msg->tx_len) | GEN_HTYPE(msg->type);
    - u32 remainder = 0;
    + u32 remainder;
    u32 val;

    if (msg->tx_len < 3) {
    @@ -621,12 +621,14 @@ static int dw_mipi_dsi_dcs_long_write(struct dw_mipi_dsi *dsi,

    while (DIV_ROUND_UP(len, pld_data_bytes)) {
    if (len < pld_data_bytes) {
    + remainder = 0;
    memcpy(&remainder, tx_buf, len);
    dsi_write(dsi, DSI_GEN_PLD_DATA, remainder);
    len = 0;
    } else {
    - dsi_write(dsi, DSI_GEN_PLD_DATA, *tx_buf);
    - tx_buf++;
    + memcpy(&remainder, tx_buf, pld_data_bytes);
    + dsi_write(dsi, DSI_GEN_PLD_DATA, remainder);
    + tx_buf += pld_data_bytes;
    len -= pld_data_bytes;
    }

    --
    2.11.0.197.gb556de5.dirty
    \
     
     \ /
      Last update: 2017-01-29 15:10    [W:2.245 / U:0.392 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site