[PATCH 2/2] pwm: meson: support meson A1 SoC family
Jerome Brunet
jbrunet at baylibre.com
Tue Apr 23 10:35:15 PDT 2024
On Tue 23 Apr 2024 at 19:10, George Stark <gnstark at salutedevices.com> wrote:
> From: George Stark <gnstark at sberdevices.ru>
>
> Add a compatible string and configuration for the meson A1 SoC family
> PWM. Additionally, provide an external clock initialization helper
> specifically designed for these PWM IPs.
>
> Signed-off-by: George Stark <gnstark at sberdevices.ru>
> Signed-off-by: Dmitry Rokosov <ddrokosov at salutedevices.com>
> ---
> drivers/pwm/pwm-meson.c | 35 +++++++++++++++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
>
> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
> index ea96c5973488..529a541ba7b6 100644
> --- a/drivers/pwm/pwm-meson.c
> +++ b/drivers/pwm/pwm-meson.c
> @@ -462,6 +462,33 @@ static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip)
> return meson_pwm_init_clocks_meson8b(chip, mux_parent_data);
> }
>
> +static int meson_pwm_init_channels_ext_clock(struct pwm_chip *chip)
That kind on naming (ext) is almost sure to clash with whatever comes next.
Just use the name of the first SoC using the method, a1 for instance.
> +{
> + struct device *dev = pwmchip_parent(chip);
> + struct meson_pwm *meson = to_meson_pwm(chip);
> + struct meson_pwm_channel *channels = meson->channels;
> + struct clk_bulk_data *clks = NULL;
> + unsigned int i;
> + int res;
> +
> + res = devm_clk_bulk_get_all(dev, &clks);
> + if (res < 0) {
> + dev_err(dev, "can't get device clocks\n");
> + return res;
> + }
I don't think allocating the 'clk_bulk_data *clks' is necessary or safe.
We know exactly how many clocks we expect, there is no need for a get all.
> +
> + if (res != MESON_NUM_PWMS) {
> + dev_err(dev, "clock count must be %d, got %d\n",
> + MESON_NUM_PWMS, res);
> + return -EINVAL;
> + }
... and this only catches the problem after the fact.
It is probably convinient but not necessary.
> +
> + for (i = 0; i < MESON_NUM_PWMS; i++)
> + channels[i].clk = clks[i].clk;
channels[i].clk could be assigned directly of_clk_get() using clock
indexes. No extra allocation needed.
> +
> + return 0;
> +}
> +
> static const struct meson_pwm_data pwm_meson8b_data = {
> .parent_names = { "xtal", NULL, "fclk_div4", "fclk_div3" },
> .channels_init = meson_pwm_init_channels_meson8b_legacy,
> @@ -500,11 +527,19 @@ static const struct meson_pwm_data pwm_meson8_v2_data = {
> .channels_init = meson_pwm_init_channels_meson8b_v2,
> };
>
> +static const struct meson_pwm_data pwm_meson_ext_clock_data = {
> + .channels_init = meson_pwm_init_channels_ext_clock,
> +};
> +
> static const struct of_device_id meson_pwm_matches[] = {
> {
> .compatible = "amlogic,meson8-pwm-v2",
> .data = &pwm_meson8_v2_data
> },
> + {
> + .compatible = "amlogic,meson-a1-pwm",
> + .data = &pwm_meson_ext_clock_data
> + },
> /* The following compatibles are obsolete */
> {
> .compatible = "amlogic,meson8b-pwm",
--
Jerome
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