[PATCH v4 02/16] drm/dsi: Add DSI transfer helper

[Thierry Reding]

From: Thierry Reding <tred...@nvidia.com>

A common pattern is starting to emerge for higher level transfer
helpers. Create a new helper that encapsulates this pattern and avoids
code duplication.

Signed-off-by: Thierry Reding <treding at nvidia.com>
---
 drivers/gpu/drm/drm_mipi_dsi.c | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
index 76e81aba8220..89a228b4eacc 100644
--- a/drivers/gpu/drm/drm_mipi_dsi.c
+++ b/drivers/gpu/drm/drm_mipi_dsi.c
@@ -198,6 +198,20 @@ int mipi_dsi_detach(struct mipi_dsi_device *dsi)
 }
 EXPORT_SYMBOL(mipi_dsi_detach);

+static ssize_t mipi_dsi_device_transfer(struct mipi_dsi_device *dsi,
+                                       struct mipi_dsi_msg *msg)
+{
+       const struct mipi_dsi_host_ops *ops = dsi->host->ops;
+
+       if (!ops || !ops->transfer)
+               return -ENOSYS;
+
+       if (dsi->mode_flags & MIPI_DSI_MODE_LPM)
+               msg->flags |= MIPI_DSI_MSG_USE_LPM;
+
+       return ops->transfer(dsi->host, msg);
+}
+
 /**
  * mipi_dsi_create_packet - create a packet from a message according to the
  *     DSI protocol
@@ -252,16 +266,12 @@ EXPORT_SYMBOL(mipi_dsi_create_packet);
 ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, const void *data,
                            size_t len)
 {
-       const struct mipi_dsi_host_ops *ops = dsi->host->ops;
        struct mipi_dsi_msg msg = {
                .channel = dsi->channel,
                .tx_buf = data,
                .tx_len = len
        };

-       if (!ops || !ops->transfer)
-               return -ENOSYS;
-
        switch (len) {
        case 0:
                return -EINVAL;
@@ -276,10 +286,7 @@ ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, 
const void *data,
                break;
        }

-       if (dsi->mode_flags & MIPI_DSI_MODE_LPM)
-               msg.flags = MIPI_DSI_MSG_USE_LPM;
-
-       return ops->transfer(dsi->host, &msg);
+       return mipi_dsi_device_transfer(dsi, &msg);
 }
 EXPORT_SYMBOL(mipi_dsi_dcs_write);

@@ -295,7 +302,6 @@ EXPORT_SYMBOL(mipi_dsi_dcs_write);
 ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 cmd, void *data,
                          size_t len)
 {
-       const struct mipi_dsi_host_ops *ops = dsi->host->ops;
        struct mipi_dsi_msg msg = {
                .channel = dsi->channel,
                .type = MIPI_DSI_DCS_READ,
@@ -305,13 +311,7 @@ ssize_t mipi_dsi_dcs_read(struct mipi_dsi_device *dsi, u8 
cmd, void *data,
                .rx_len = len
        };

-       if (!ops || !ops->transfer)
-               return -ENOSYS;
-
-       if (dsi->mode_flags & MIPI_DSI_MODE_LPM)
-               msg.flags = MIPI_DSI_MSG_USE_LPM;
-
-       return ops->transfer(dsi->host, &msg);
+       return mipi_dsi_device_transfer(dsi, &msg);
 }
 EXPORT_SYMBOL(mipi_dsi_dcs_read);

-- 
2.1.2