V4L/DVB (9953): em28xx: Add suport for debugging AC97 anciliary chips
The em28xx driver can be coupled to an anciliary AC97 chip. This patch
allows read/write AC97 registers directly.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/em28xx/em28xx-core.c b/drivers/media/video/em28xx/em28xx-core.c
index c647dcb..5964998 100644
--- a/drivers/media/video/em28xx/em28xx-core.c
+++ b/drivers/media/video/em28xx/em28xx-core.c
@@ -259,7 +259,7 @@
* em28xx_read_ac97()
* write a 16 bit value to the specified AC97 address (LSB first!)
*/
-static int em28xx_read_ac97(struct em28xx *dev, u8 reg)
+int em28xx_read_ac97(struct em28xx *dev, u8 reg)
{
int ret;
u8 addr = (reg & 0x7f) | 0x80;
@@ -285,7 +285,7 @@
* em28xx_write_ac97()
* write a 16 bit value to the specified AC97 address (LSB first!)
*/
-static int em28xx_write_ac97(struct em28xx *dev, u8 reg, u16 val)
+int em28xx_write_ac97(struct em28xx *dev, u8 reg, u16 val)
{
int ret;
u8 addr = reg & 0x7f;
diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c
index 4701b65..4ea4920 100644
--- a/drivers/media/video/em28xx/em28xx-video.c
+++ b/drivers/media/video/em28xx/em28xx-video.c
@@ -1221,6 +1221,17 @@
struct em28xx *dev = fh->dev;
int ret;
+ if (reg->match_type == V4L2_CHIP_MATCH_AC97) {
+ mutex_lock(&dev->lock);
+ ret = em28xx_read_ac97(dev, reg->reg);
+ mutex_unlock(&dev->lock);
+ if (ret < 0)
+ return ret;
+
+ reg->val = ret;
+ return 0;
+ }
+
if (!v4l2_chip_match_host(reg->match_type, reg->match_chip))
return -EINVAL;
@@ -1256,6 +1267,14 @@
__le64 buf;
int rc;
+ if (reg->match_type == V4L2_CHIP_MATCH_AC97) {
+ mutex_lock(&dev->lock);
+ rc = em28xx_write_ac97(dev, reg->reg, reg->val);
+ mutex_unlock(&dev->lock);
+
+ return rc;
+ }
+
buf = cpu_to_le64(reg->val);
mutex_lock(&dev->lock);
diff --git a/drivers/media/video/em28xx/em28xx.h b/drivers/media/video/em28xx/em28xx.h
index 80d1d55..100f278 100644
--- a/drivers/media/video/em28xx/em28xx.h
+++ b/drivers/media/video/em28xx/em28xx.h
@@ -564,6 +564,9 @@
int em28xx_write_regs(struct em28xx *dev, u16 reg, char *buf, int len);
int em28xx_write_reg(struct em28xx *dev, u16 reg, u8 val);
+int em28xx_read_ac97(struct em28xx *dev, u8 reg);
+int em28xx_write_ac97(struct em28xx *dev, u8 reg, u16 val);
+
int em28xx_audio_analog_set(struct em28xx *dev);
int em28xx_audio_setup(struct em28xx *dev);
diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 754c8d9..e31144d 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -1376,6 +1376,7 @@
#define V4L2_CHIP_MATCH_HOST 0 /* Match against chip ID on host (0 for the host) */
#define V4L2_CHIP_MATCH_I2C_DRIVER 1 /* Match against I2C driver ID */
#define V4L2_CHIP_MATCH_I2C_ADDR 2 /* Match against I2C 7-bit address */
+#define V4L2_CHIP_MATCH_AC97 3 /* Match against anciliary AC97 chip */
struct v4l2_register {
__u32 match_type; /* Match type */