[PATCH] drm/mediatek: dsi: fix error codes in mtk_dsi_host_transfer()

[Dan Carpenter]

There is a type bug because the return statement:

        return ret < 0 ? ret : recv_cnt;

will not return negatives on 64bit systems.  The problem is that the
function returns ssize_t types, while "ret" is int and "recv_cnt" is a
u32.  The negative values are type promoted to u32 and returned as
positive values instead of negative error codes.

Fixes: 81cc7e51c4f1 ("drm/mediatek: Allow commands to be sent during video 
mode")
Signed-off-by: Dan Carpenter <erro...@gmail.com>
---
 drivers/gpu/drm/mediatek/mtk_dsi.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c 
b/drivers/gpu/drm/mediatek/mtk_dsi.c
index 7d5250351193..8e99981ca0e1 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -1016,12 +1016,12 @@ static ssize_t mtk_dsi_host_transfer(struct 
mipi_dsi_host *host,
                                     const struct mipi_dsi_msg *msg)
 {
        struct mtk_dsi *dsi = host_to_dsi(host);
-       u32 recv_cnt, i;
+       ssize_t recv_cnt;
        u8 read_data[16];
        void *src_addr;
        u8 irq_flag = CMD_DONE_INT_FLAG;
        u32 dsi_mode;
-       int ret;
+       int ret, i;
 
        dsi_mode = readl(dsi->regs + DSI_MODE_CTRL);
        if (dsi_mode & MODE) {
@@ -1070,7 +1070,7 @@ static ssize_t mtk_dsi_host_transfer(struct mipi_dsi_host 
*host,
        if (recv_cnt)
                memcpy(msg->rx_buf, src_addr, recv_cnt);
 
-       DRM_INFO("dsi get %d byte data from the panel address(0x%x)\n",
+       DRM_INFO("dsi get %zd byte data from the panel address(0x%x)\n",
                 recv_cnt, *((u8 *)(msg->tx_buf)));
 
 restore_dsi_mode:
-- 
2.39.1