drm/gma500: Fix SDVO command debug printing

At some point the DRM printers started adding a newline after each
print. This caused SDVO command debug printing to look weird. Fix this
by using snprintf to print into a buffer which can be printed as a whole
by DRM_DEBUG_KMS(). Code is heavily inspired by i915.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220610130925.8650-1-patrik.r.jakobsson@gmail.com

diff --git a/drivers/gpu/drm/gma500/psb_intel_sdvo.c b/drivers/gpu/drm/gma500/psb_intel_sdvo.c
index a85aace..bdced46 100644 (file)
--- a/drivers/gpu/drm/gma500/psb_intel_sdvo.c
+++ b/drivers/gpu/drm/gma500/psb_intel_sdvo.c
@@ -400,26 +400,38 @@ static const struct _sdvo_cmd_name {
 #define IS_SDVOB(reg)  (reg == SDVOB)
 #define SDVO_NAME(svdo) (IS_SDVOB((svdo)->sdvo_reg) ? "SDVOB" : "SDVOC")
 
-static void psb_intel_sdvo_debug_write(struct psb_intel_sdvo *psb_intel_sdvo, u8 cmd,
-                                  const void *args, int args_len)
+static void psb_intel_sdvo_debug_write(struct psb_intel_sdvo *psb_intel_sdvo,
+                                      u8 cmd, const void *args, int args_len)
 {
-       int i;
+       struct drm_device *dev = psb_intel_sdvo->base.base.dev;
+       int i, pos = 0;
+       char buffer[73];
+
+#define BUF_PRINT(args...) \
+       pos += snprintf(buffer + pos, max_t(int, sizeof(buffer) - pos, 0), args)
+
+       for (i = 0; i < args_len; i++) {
+               BUF_PRINT("%02X ", ((u8 *)args)[i]);
+       }
+
+       for (; i < 8; i++) {
+               BUF_PRINT("   ");
+       }
 
-       DRM_DEBUG_KMS("%s: W: %02X ",
-                               SDVO_NAME(psb_intel_sdvo), cmd);
-       for (i = 0; i < args_len; i++)
-               DRM_DEBUG_KMS("%02X ", ((u8 *)args)[i]);
-       for (; i < 8; i++)
-               DRM_DEBUG_KMS("   ");
        for (i = 0; i < ARRAY_SIZE(sdvo_cmd_names); i++) {
                if (cmd == sdvo_cmd_names[i].cmd) {
-                       DRM_DEBUG_KMS("(%s)", sdvo_cmd_names[i].name);
+                       BUF_PRINT("(%s)", sdvo_cmd_names[i].name);
                        break;
                }
        }
+
        if (i == ARRAY_SIZE(sdvo_cmd_names))
-               DRM_DEBUG_KMS("(%02X)", cmd);
-       DRM_DEBUG_KMS("\n");
+               BUF_PRINT("(%02X)", cmd);
+
+       drm_WARN_ON(dev, pos >= sizeof(buffer) - 1);
+#undef BUF_PRINT
+
+       DRM_DEBUG_KMS("%s: W: %02X %s\n", SDVO_NAME(psb_intel_sdvo), cmd, buffer);
 }
 
 static const char *cmd_status_names[] = {
@@ -490,13 +502,13 @@ static bool psb_intel_sdvo_write_cmd(struct psb_intel_sdvo *psb_intel_sdvo, u8 c
 }
 
 static bool psb_intel_sdvo_read_response(struct psb_intel_sdvo *psb_intel_sdvo,
-                                    void *response, int response_len)
+                                        void *response, int response_len)
 {
+       struct drm_device *dev = psb_intel_sdvo->base.base.dev;
+       char buffer[73];
+       int i, pos = 0;
        u8 retry = 5;
        u8 status;
-       int i;
-
-       DRM_DEBUG_KMS("%s: R: ", SDVO_NAME(psb_intel_sdvo));
 
        /*
         * The documentation states that all commands will be
@@ -520,10 +532,13 @@ static bool psb_intel_sdvo_read_response(struct psb_intel_sdvo *psb_intel_sdvo,
                        goto log_fail;
        }
 
+#define BUF_PRINT(args...) \
+       pos += snprintf(buffer + pos, max_t(int, sizeof(buffer) - pos, 0), args)
+
        if (status <= SDVO_CMD_STATUS_SCALING_NOT_SUPP)
-               DRM_DEBUG_KMS("(%s)", cmd_status_names[status]);
+               BUF_PRINT("(%s)", cmd_status_names[status]);
        else
-               DRM_DEBUG_KMS("(??? %d)", status);
+               BUF_PRINT("(??? %d)", status);
 
        if (status != SDVO_CMD_STATUS_SUCCESS)
                goto log_fail;
@@ -534,13 +549,18 @@ static bool psb_intel_sdvo_read_response(struct psb_intel_sdvo *psb_intel_sdvo,
                                          SDVO_I2C_RETURN_0 + i,
                                          &((u8 *)response)[i]))
                        goto log_fail;
-               DRM_DEBUG_KMS(" %02X", ((u8 *)response)[i]);
+               BUF_PRINT(" %02X", ((u8 *)response)[i]);
        }
-       DRM_DEBUG_KMS("\n");
+
+       drm_WARN_ON(dev, pos >= sizeof(buffer) - 1);
+#undef BUF_PRINT
+
+       DRM_DEBUG_KMS("%s: R: %s\n", SDVO_NAME(psb_intel_sdvo), buffer);
        return true;
 
 log_fail:
-       DRM_DEBUG_KMS("... failed\n");
+       DRM_DEBUG_KMS("%s: R: ... failed %s\n",
+                     SDVO_NAME(psb_intel_sdvo), buffer);
        return false;
 }