Morning Hans
On 27/06/2023 15:18, Hans de Goede wrote:
On ACPI systems the following 2 scenarios are possible:
1. The xvclk is fully controlled by ACPI powermanagement, so there
is no "xvclk" for the driver to get (since it is abstracted away).
In this case there will be a "clock-frequency" device property
to tell the driver the xvclk rate.
2. There is a xvclk modelled in the clk framework for the driver,
but the clk-generator may not be set to the right frequency
yet. In this case there will also be a "clock-frequency" device
property and the driver is expected to set the rate of the xvclk
through this frequency through the clk framework.
Handle both these scenarios by switching to devm_clk_get_optional()
and checking for a "clock-frequency" device property.
This is modelled after how the same issue was fixed for the ov8865 in
commit 73dcffeb2ff9 ("media: i2c: Support 19.2MHz input clock in ov8865").
Acked-by: Rui Miguel Silva <rmfrfs@xxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Reviewed-by: Daniel Scally <dan.scally@xxxxxxxxxxxxxxxx>
drivers/media/i2c/ov2680.c | 26 ++++++++++++++++++++++++--
1 file changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/media/i2c/ov2680.c b/drivers/media/i2c/ov2680.c
index b7c23286700e..a6a83f0e53f3 100644
--- a/drivers/media/i2c/ov2680.c
+++ b/drivers/media/i2c/ov2680.c
@@ -698,6 +698,7 @@ static int ov2680_parse_dt(struct ov2680_dev *sensor)
{
struct device *dev = sensor->dev;
struct gpio_desc *gpio;
+ unsigned int rate = 0;
int ret;
/*
@@ -718,13 +719,34 @@ static int ov2680_parse_dt(struct ov2680_dev *sensor)
sensor->pwdn_gpio = gpio;
- sensor->xvclk = devm_clk_get(dev, "xvclk");
+ sensor->xvclk = devm_clk_get_optional(dev, "xvclk");
if (IS_ERR(sensor->xvclk)) {
dev_err(dev, "xvclk clock missing or invalid\n");
return PTR_ERR(sensor->xvclk);
}
- sensor->xvclk_freq = clk_get_rate(sensor->xvclk);
+ /*
+ * We could have either a 24MHz or 19.2MHz clock rate from either DT or
+ * ACPI... but we also need to support the weird IPU3 case which will
+ * have an external clock AND a clock-frequency property. Check for the
+ * clock-frequency property and if found, set that rate if we managed
+ * to acquire a clock. This should cover the ACPI case. If the system
+ * uses devicetree then the configured rate should already be set, so
+ * we can just read it.
+ */
+ ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
+ &rate);
+ if (ret && !sensor->xvclk)
+ return dev_err_probe(dev, ret, "invalid clock config\n");
+
+ if (!ret && sensor->xvclk) {
+ ret = clk_set_rate(sensor->xvclk, rate);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "failed to set clock rate\n");
+ }
+
+ sensor->xvclk_freq = rate ?: clk_get_rate(sensor->xvclk);
if (sensor->xvclk_freq != OV2680_XVCLK_VALUE) {
dev_err(dev, "wrong xvclk frequency %d HZ, expected: %d Hz\n",
sensor->xvclk_freq, OV2680_XVCLK_VALUE);
