diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0874-media-i2c-ov9281-Read-chip-ID-via-2-reads.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0874-media-i2c-ov9281-Read-chip-ID-via-2-reads.patch | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0874-media-i2c-ov9281-Read-chip-ID-via-2-reads.patch b/target/linux/bcm27xx/patches-5.4/950-0874-media-i2c-ov9281-Read-chip-ID-via-2-reads.patch new file mode 100644 index 0000000000..0b06442a3e --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0874-media-i2c-ov9281-Read-chip-ID-via-2-reads.patch @@ -0,0 +1,42 @@ +From 5c6b7b60d7d607b59b4208e758180d4f93be8788 Mon Sep 17 00:00:00 2001 +From: Dave Stevenson <dave.stevenson@raspberrypi.com> +Date: Mon, 6 Jul 2020 17:51:32 +0100 +Subject: [PATCH] media: i2c: ov9281: Read chip ID via 2 reads + +Vision Components have made an OV9281 module which blocks reading +back the majority of registers to comply with NDAs, and in doing +so doesn't allow auto-increment register reading as used when +reading the chip ID. + +Use two reads and manually combine the results. + +Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com> +--- + drivers/media/i2c/ov9281.c | 14 +++++++++----- + 1 file changed, 9 insertions(+), 5 deletions(-) + +--- a/drivers/media/i2c/ov9281.c ++++ b/drivers/media/i2c/ov9281.c +@@ -904,13 +904,17 @@ static int ov9281_check_sensor_id(struct + struct i2c_client *client) + { + struct device *dev = &ov9281->client->dev; +- u32 id = 0; ++ u32 id = 0, id_msb; + int ret; + +- ret = ov9281_read_reg(client, OV9281_REG_CHIP_ID, +- OV9281_REG_VALUE_16BIT, &id); +- if (id != CHIP_ID) { +- dev_err(dev, "Unexpected sensor id(%06x), ret(%d)\n", id, ret); ++ ret = ov9281_read_reg(client, OV9281_REG_CHIP_ID + 1, ++ OV9281_REG_VALUE_08BIT, &id); ++ if (!ret) ++ ret = ov9281_read_reg(client, OV9281_REG_CHIP_ID, ++ OV9281_REG_VALUE_08BIT, &id_msb); ++ id |= (id_msb << 8); ++ if (ret || id != CHIP_ID) { ++ dev_err(dev, "Unexpected sensor id(%04x), ret(%d)\n", id, ret); + return -ENODEV; + } + |