The embedded OV490 ISP chip provides a secondary SCCB interface and
two GPIO lines to control the connected OV10640 image sensor.
Break out the OV10640 initialization from the OV490 initialization and
explicitely control the powerdown and reset GPIOs. After the image
sensor has been hard reset, implement a more clear handling of the
secondary SCCB interface to read the image sensor chip ID.
Signed-off-by: Jacopo Mondi <jacopo+rene...@jmondi.org>
---
drivers/media/i2c/rdacm21.c | 75 ++++++++++++++++++++++++++++++-------
1 file changed, 61 insertions(+), 14 deletions(-)
diff --git a/drivers/media/i2c/rdacm21.c b/drivers/media/i2c/rdacm21.c
index 0428e3209463..944009687de5 100644
--- a/drivers/media/i2c/rdacm21.c
+++ b/drivers/media/i2c/rdacm21.c
@@ -30,11 +30,24 @@
#define OV490_PAGE_HIGH_REG 0xfffd
#define OV490_PAGE_LOW_REG 0xfffe
+/*
+ * The SCCB slave handling is undocumented; the registers naming scheme is
+ * totally arbitrary.
+ */
+#define OV490_SCCB_SLAVE_WRITE 0x00
+#define OV490_SCCB_SLAVE_READ 0x01
+#define OV490_SCCB_SLAVE0_DIR 0x80195000
+#define OV490_SCCB_SLAVE0_ADDR_HIGH 0x80195001
+#define OV490_SCCB_SLAVE0_ADDR_LOW 0x80195002
+
#define OV490_DVP_CTRL3 0x80286009
#define OV490_ODS_CTRL_FRAME_OUTPUT_EN 0x0c
#define OV490_ODS_CTRL 0x8029d000
+#define OV490_HOST_CMD 0x808000c0
+#define OV490_HOST_CMD_TRIGGER 0xc1
+
#define OV490_ID_VAL 0x0490
#define OV490_ID(_p, _v) ((((_p) & 0xff) << 8) | ((_v) & 0xff))
#define OV490_PID 0x8080300a
@@ -42,12 +55,22 @@
#define OV490_PID_TIMEOUT 20
#define OV490_OUTPUT_EN_TIMEOUT 300
+#define OV490_GPIO0_RESETB 0x01
+#define OV490_SPWDN0 0x01
+#define OV490_GPIO_SEL0 0x80800050
+#define OV490_GPIO_SEL1 0x80800051
+#define OV490_GPIO_DIRECTION0 0x80800054
+#define OV490_GPIO_DIRECTION1 0x80800055
+#define OV490_GPIO_OUTPUT_VALUE0 0x80800058
+#define OV490_GPIO_OUTPUT_VALUE1 0x80800059
+
#define OV490_ISP_HSIZE_LOW 0x80820060
#define OV490_ISP_HSIZE_HIGH 0x80820061
#define OV490_ISP_VSIZE_LOW 0x80820062
#define OV490_ISP_VSIZE_HIGH 0x80820063
-#define OV10640_ID_LOW 0xa6
+#define OV10640_ID_HIGH 0xa6
+#define OV10640_CHIP_ID 0x300a
#define OV10640_PIXEL_RATE 55000000
struct rdacm21_device {
@@ -306,6 +329,39 @@ static const struct v4l2_subdev_ops rdacm21_subdev_ops = {
.pad = &rdacm21_subdev_pad_ops,
};
+static int ov10640_initialize(struct rdacm21_device *dev)
+{
+ u8 val;
+
+ /* Power-up OV10640 by setting RESETB and PWDNB pins high. */
+ ov490_write_reg(dev, OV490_GPIO_SEL0, OV490_GPIO0_RESETB);
+ ov490_write_reg(dev, OV490_GPIO_SEL1, OV490_SPWDN0);
+ ov490_write_reg(dev, OV490_GPIO_DIRECTION0, OV490_GPIO0_RESETB);
+ ov490_write_reg(dev, OV490_GPIO_DIRECTION1, OV490_SPWDN0);
+ ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_GPIO0_RESETB);
+ ov490_write_reg(dev, OV490_GPIO_OUTPUT_VALUE0, OV490_SPWDN0);
+ usleep_range(3000, 5000);
+
+ /* Read OV10640 ID to test communications. */
+ ov490_write_reg(dev, OV490_SCCB_SLAVE0_DIR, OV490_SCCB_SLAVE_READ);
+ ov490_write_reg(dev, OV490_SCCB_SLAVE0_ADDR_HIGH, OV10640_CHIP_ID >> 8);
+ ov490_write_reg(dev, OV490_SCCB_SLAVE0_ADDR_LOW, (u8)OV10640_CHIP_ID);
+
+ /* Trigger SCCB slave transaction and give it some time to complete. */
+ ov490_write_reg(dev, OV490_HOST_CMD, OV490_HOST_CMD_TRIGGER);
+ usleep_range(1000, 1500);
+
+ ov490_read_reg(dev, OV490_SCCB_SLAVE0_DIR, &val);
+ if (val != OV10640_ID_HIGH) {
+ dev_err(dev->dev, "OV10640 ID mismatch: (0x%02x)\n", val);
+ return -ENODEV;
+ }
+
+ dev_dbg(dev->dev, "OV10640 ID = 0x%2x\n", val);
+
+ return 0;
+}
+
static int ov490_initialize(struct rdacm21_device *dev)
{
u8 pid, ver, val;
@@ -349,20 +405,11 @@ static int ov490_initialize(struct rdacm21_device *dev)
return -ENODEV;
}
- /* Read OV10640 Id to test communications. */
- ov490_write_reg(dev, 0x80195000, 0x01);
- ov490_write_reg(dev, 0x80195001, 0x30);
- ov490_write_reg(dev, 0x80195002, 0x0a);
- ov490_write_reg(dev, 0x808000c0, 0xc1);
-
- ov490_read_reg(dev, 0x80195000, &val);
- if (val != OV10640_ID_LOW) {
- dev_err(dev->dev, "OV10640 ID mismatch: (0x%02x)\n", val);
- return -ENODEV;
- }
-
- dev_dbg(dev->dev, "OV10640 ID = 0x%2x\n", val);
+ ret = ov10640_initialize(dev);
+ if (ret)
+ return ret;
+ /* Program OV490 with register-value table. */
for (i = 0; i < ARRAY_SIZE(ov490_regs_wizard); ++i) {
ret = ov490_write(dev, ov490_regs_wizard[i].reg,
ov490_regs_wizard[i].val);
--
2.29.2
