On 05. 12. 20 19:54, Geert Uytterhoeven wrote:
> Hi Michael,
>
> On Sat, Dec 5, 2020 at 7:36 PM <michael.srba@xxxxxxxxx> wrote:
>> From: Michael Srba <Michael.Srba@xxxxxxxxx>
>>
>> This patch adds 1% tolerance on input clock, similar to other camera sensor
>> drivers. It also allows for specifying the actual clock in the device tree,
>> instead of relying on it being already set to the right frequency (which is
>> often not the case).
>>
>> Signed-off-by: Michael Srba <Michael.Srba@xxxxxxxxx>
> Thanks for your patch!
>
>> --- a/drivers/media/i2c/imx219.c
>> +++ b/drivers/media/i2c/imx219.c
>> @@ -1443,13 +1443,26 @@ static int imx219_probe(struct i2c_client *client)
>> return PTR_ERR(imx219->xclk);
>> }
>>
>> - imx219->xclk_freq = clk_get_rate(imx219->xclk);
>> - if (imx219->xclk_freq != IMX219_XCLK_FREQ) {
>> + ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency", &imx219->xclk_freq);
>> + if (ret) {
>> + dev_err(dev, "could not get xclk frequency\n");
>> + return ret;
> This breaks compatibility with existing DTBs, which do not have the
> clock-frequency property.
> For backwards compatibility, you should assume the default 24 MHz
> instead of returning an error.
Good point, will do.
>> + }
>> +
>> + /* this driver currently expects 24MHz; allow 1% tolerance */
>> + if (imx219->xclk_freq < 23760000 || imx219->xclk_freq > 24240000) {
>> dev_err(dev, "xclk frequency not supported: %d Hz\n",
>> imx219->xclk_freq);
>> return -EINVAL;
>> }
>>
>> + ret = clk_set_rate(imx219->xclk, imx219->xclk_freq);
>> + if (ret) {
>> + dev_err(dev, "could not set xclk frequency\n");
>> + return ret;
>> + }
>> +
>> +
>> ret = imx219_get_regulators(imx219);
>> if (ret) {
>> dev_err(dev, "failed to get regulators\n");
> Gr{oetje,eeting}s,
>
> Geert
>
Michael
