media: cec: make cec_get_edid_spa_location() an inline function

This function is needed by both V4L2 and CEC, so move this to
cec.h as a static inline since there are no obvious shared
modules between the two subsystems.

This patch, together with the following ones, fixes a
dependency bug: if CEC_CORE is disabled, then building adv7604
(and other HDMI receivers) will fail because an essential
function is now stubbed out.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v4.17 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/cec/cec-edid.c b/drivers/media/cec/cec-edid.c
index ec72ac1c0b915ef70de9b1bf86707d5cf0fe2585..f587e8eaefd81b75ccec06060d14737189733ab3 100644 (file)
--- a/drivers/media/cec/cec-edid.c
+++ b/drivers/media/cec/cec-edid.c
@@ -10,66 +10,6 @@
 #include <linux/types.h>
 #include <media/cec.h>
 
-/*
- * This EDID is expected to be a CEA-861 compliant, which means that there are
- * at least two blocks and one or more of the extensions blocks are CEA-861
- * blocks.
- *
- * The returned location is guaranteed to be < size - 1.
- */
-static unsigned int cec_get_edid_spa_location(const u8 *edid, unsigned int size)
-{
-       unsigned int blocks = size / 128;
-       unsigned int block;
-       u8 d;
-
-       /* Sanity check: at least 2 blocks and a multiple of the block size */
-       if (blocks < 2 || size % 128)
-               return 0;
-
-       /*
-        * If there are fewer extension blocks than the size, then update
-        * 'blocks'. It is allowed to have more extension blocks than the size,
-        * since some hardware can only read e.g. 256 bytes of the EDID, even
-        * though more blocks are present. The first CEA-861 extension block
-        * should normally be in block 1 anyway.
-        */
-       if (edid[0x7e] + 1 < blocks)
-               blocks = edid[0x7e] + 1;
-
-       for (block = 1; block < blocks; block++) {
-               unsigned int offset = block * 128;
-
-               /* Skip any non-CEA-861 extension blocks */
-               if (edid[offset] != 0x02 || edid[offset + 1] != 0x03)
-                       continue;
-
-               /* search Vendor Specific Data Block (tag 3) */
-               d = edid[offset + 2] & 0x7f;
-               /* Check if there are Data Blocks */
-               if (d <= 4)
-                       continue;
-               if (d > 4) {
-                       unsigned int i = offset + 4;
-                       unsigned int end = offset + d;
-
-                       /* Note: 'end' is always < 'size' */
-                       do {
-                               u8 tag = edid[i] >> 5;
-                               u8 len = edid[i] & 0x1f;
-
-                               if (tag == 3 && len >= 5 && i + len <= end &&
-                                   edid[i + 1] == 0x03 &&
-                                   edid[i + 2] == 0x0c &&
-                                   edid[i + 3] == 0x00)
-                                       return i + 4;
-                               i += len + 1;
-                       } while (i < end);
-               }
-       }
-       return 0;
-}
-
 u16 cec_get_edid_phys_addr(const u8 *edid, unsigned int size,
                           unsigned int *offset)
 {

diff --git a/include/media/cec.h b/include/media/cec.h
index ff9847f7f99d28f83af74d832b1a2d604ccb0657..603f2fa08f625e044fcfc9bf35f627446fdeefc5 100644 (file)
--- a/include/media/cec.h
+++ b/include/media/cec.h
@@ -461,4 +461,74 @@ static inline void cec_phys_addr_invalidate(struct cec_adapter *adap)
        cec_s_phys_addr(adap, CEC_PHYS_ADDR_INVALID, false);
 }
 
+/**
+ * cec_get_edid_spa_location() - find location of the Source Physical Address
+ *
+ * @edid: the EDID
+ * @size: the size of the EDID
+ *
+ * This EDID is expected to be a CEA-861 compliant, which means that there are
+ * at least two blocks and one or more of the extensions blocks are CEA-861
+ * blocks.
+ *
+ * The returned location is guaranteed to be <= size-2.
+ *
+ * This is an inline function since it is used by both CEC and V4L2.
+ * Ideally this would go in a module shared by both, but it is overkill to do
+ * that for just a single function.
+ */
+static inline unsigned int cec_get_edid_spa_location(const u8 *edid,
+                                                    unsigned int size)
+{
+       unsigned int blocks = size / 128;
+       unsigned int block;
+       u8 d;
+
+       /* Sanity check: at least 2 blocks and a multiple of the block size */
+       if (blocks < 2 || size % 128)
+               return 0;
+
+       /*
+        * If there are fewer extension blocks than the size, then update
+        * 'blocks'. It is allowed to have more extension blocks than the size,
+        * since some hardware can only read e.g. 256 bytes of the EDID, even
+        * though more blocks are present. The first CEA-861 extension block
+        * should normally be in block 1 anyway.
+        */
+       if (edid[0x7e] + 1 < blocks)
+               blocks = edid[0x7e] + 1;
+
+       for (block = 1; block < blocks; block++) {
+               unsigned int offset = block * 128;
+
+               /* Skip any non-CEA-861 extension blocks */
+               if (edid[offset] != 0x02 || edid[offset + 1] != 0x03)
+                       continue;
+
+               /* search Vendor Specific Data Block (tag 3) */
+               d = edid[offset + 2] & 0x7f;
+               /* Check if there are Data Blocks */
+               if (d <= 4)
+                       continue;
+               if (d > 4) {
+                       unsigned int i = offset + 4;
+                       unsigned int end = offset + d;
+
+                       /* Note: 'end' is always < 'size' */
+                       do {
+                               u8 tag = edid[i] >> 5;
+                               u8 len = edid[i] & 0x1f;
+
+                               if (tag == 3 && len >= 5 && i + len <= end &&
+                                   edid[i + 1] == 0x03 &&
+                                   edid[i + 2] == 0x0c &&
+                                   edid[i + 3] == 0x00)
+                                       return i + 4;
+                               i += len + 1;
+                       } while (i < end);
+               }
+       }
+       return 0;
+}
+
 #endif /* _MEDIA_CEC_H */