diff options
Diffstat (limited to 'meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0068-drm-adv7511-use-smbus-to-retrieve-edid.patch')
| -rw-r--r-- | meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0068-drm-adv7511-use-smbus-to-retrieve-edid.patch | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0068-drm-adv7511-use-smbus-to-retrieve-edid.patch b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0068-drm-adv7511-use-smbus-to-retrieve-edid.patch new file mode 100644 index 0000000..1b4dbd8 --- /dev/null +++ b/meta-rcar-gen3-adas/recipes-kernel/linux/linux-renesas/0068-drm-adv7511-use-smbus-to-retrieve-edid.patch @@ -0,0 +1,53 @@ +From 2e2b673a2a47e8358ef92ec4019be87552949304 Mon Sep 17 00:00:00 2001 +From: Vladimir Barinov <vladimir.barinov@cogentembedded.com> +Date: Wed, 9 Aug 2017 11:52:22 +0300 +Subject: [PATCH] drm: adv7511: use smbus to retrieve edid + +Get EDID using smbus protocol instead block i2c transfer +This fixes often checksum errors while retriving EDID at 400kHz bus speed + +Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com> +--- + drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 9 +++++---- + 1 file changed, 5 insertions(+), 4 deletions(-) + +diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +index d3ece87..b2e1b58 100644 +--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c ++++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c +@@ -500,18 +500,19 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block, + * support 64 byte transfers than 256 byte transfers + */ + ++#define CHUNK_SIZE 1 + xfer[0].addr = adv7511->i2c_edid->addr; + xfer[0].flags = 0; + xfer[0].len = 1; + xfer[0].buf = &offset; + xfer[1].addr = adv7511->i2c_edid->addr; + xfer[1].flags = I2C_M_RD; +- xfer[1].len = 64; ++ xfer[1].len = CHUNK_SIZE; + xfer[1].buf = adv7511->edid_buf; + + offset = 0; + +- for (i = 0; i < 4; ++i) { ++ for (i = 0; i < 256/CHUNK_SIZE; ++i) { + ret = i2c_transfer(adv7511->i2c_edid->adapter, xfer, + ARRAY_SIZE(xfer)); + if (ret < 0) +@@ -519,8 +520,8 @@ static int adv7511_get_edid_block(void *data, u8 *buf, unsigned int block, + else if (ret != 2) + return -EIO; + +- xfer[1].buf += 64; +- offset += 64; ++ xfer[1].buf += CHUNK_SIZE; ++ offset += CHUNK_SIZE; + } + + adv7511->current_edid_segment = block / 2; +-- +1.9.1 + |