Hi Antonium
On Wed, 2024-06-12 at 13:45 +0300, Antoniu Miclaus wrote:
> Add clk provider feature for the adf4350.
>
> Even though the driver was sent as an IIO driver in most cases the
> device is actually seen as a clock provider.
>
> This patch aims to cover actual usecases requested by users in order to
> completely control the output frequencies from userspace.
>
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
> ---
> changes in v3:
> - use container_of to directly access the adf4350_state structure.
> drivers/iio/frequency/adf4350.c | 118 ++++++++++++++++++++++++++++++++
> 1 file changed, 118 insertions(+)
>
> diff --git a/drivers/iio/frequency/adf4350.c b/drivers/iio/frequency/adf4350.c
> index 4abf80f75ef5..f716f744baa9 100644
> --- a/drivers/iio/frequency/adf4350.c
> +++ b/drivers/iio/frequency/adf4350.c
> @@ -19,6 +19,7 @@
> #include <linux/gpio/consumer.h>
> #include <asm/div64.h>
> #include <linux/clk.h>
> +#include <linux/clk-provider.h>
>
> #include <linux/iio/iio.h>
> #include <linux/iio/sysfs.h>
> @@ -36,6 +37,9 @@ struct adf4350_state {
> struct gpio_desc *lock_detect_gpiod;
> struct adf4350_platform_data *pdata;
> struct clk *clk;
> + struct clk *clkout;
> + const char *clk_out_name;
> + struct clk_hw hw;
> unsigned long clkin;
> unsigned long chspc; /* Channel Spacing */
> unsigned long fpfd; /* Phase Frequency Detector */
> @@ -61,6 +65,8 @@ struct adf4350_state {
> __be32 val __aligned(IIO_DMA_MINALIGN);
> };
>
> +#define to_state(_hw) container_of(_hw, struct adf4350_state, hw)
> +
nit: to_adf4350_state() would be neater...
> static struct adf4350_platform_data default_pdata = {
> .channel_spacing = 10000,
> .r2_user_settings = ADF4350_REG2_PD_POLARITY_POS |
> @@ -264,6 +270,10 @@ static ssize_t adf4350_write(struct iio_dev *indio_dev,
> mutex_lock(&st->lock);
> switch ((u32)private) {
> case ADF4350_FREQ:
> + if (st->clkout) {
> + ret = clk_set_rate(st->clkout, readin);
> + break;
> + }
So, apparently you forgot or decided otherwise to not go with the suggestion of
not including the IIO interface (at least he channel one - debugfs could be
maintained I guess) or with the more in the middle approach Michael suggested.
Just not allowing ADF4350_FREQ and ADF4350_FREQ_REFIN.
Hence, I would expect at least some justification to keep the above in your v3
changelog. Also note that keeping ADF4350_FREQ_REFIN while being a clock
provider seems pointless and maybe even be wrong (as the clock framework should
take care of the parent clock). This also brings another question... see below
...
>
> +static int adf4350_clk_register(struct adf4350_state *st)
> +{
> + struct spi_device *spi = st->spi;
> + struct clk_init_data init;
> + struct clk *clk;
> + const char *parent_name;
> + int ret;
> +
> + if (!device_property_present(&spi->dev, "#clock-cells"))
> + return 0;
> +
> + init.name = devm_kasprintf(&spi->dev, GFP_KERNEL, "%s-clk",
> + fwnode_get_name(dev_fwnode(&spi->dev)));
> + device_property_read_string(&spi->dev, "clock-output-names",
> + &init.name);
> +
> + parent_name = of_clk_get_parent_name(spi->dev.of_node, 0);
> + if (!parent_name)
> + return -EINVAL;
> +
> + init.ops = &adf4350_clk_ops;
> + init.parent_names = &parent_name;
> + init.num_parents = 1;
Shouldn't we set CLK_SET_RATE_PARENT in init.flags?
- Nuno Sá
