Re: [PATCH v3 10/15] media: qcom: camss: Allow clocks vfeN vfe_liteN or vfe_lite

From: Laurent Pinchart
Date: Mon Aug 28 2023 - 14:56:11 EST


On Wed, Aug 23, 2023 at 11:44:39AM +0100, Bryan O'Donoghue wrote:
> The number of Video Front End - VFE or Image Front End - IFE supported
> with new SoCs can vary both for the full and lite cases.
>
> For example sdm845 has one vfe_lite and two vfe interfaces with the vfe
> clock called simply "vfe_lite" with no integer postfix. sc8280xp has four
> vfe and four vfe lite blocks.
>
> We need to support the following clock name formats
>
> - vfeN
> - vfe_liteN
> - vfe_lite
>
> with N being any reasonably sized integer.
>
> There are two sites in this code which need to do the same thing,
> constructing and matching strings with the pattern above, so encapsulate
> the logic in one function.
>
> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>
> ---
> drivers/media/platform/qcom/camss/camss-vfe.c | 22 ++++++++++++++-----
> 1 file changed, 16 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
> index 8f48401e31cd3..73380e75dbb22 100644
> --- a/drivers/media/platform/qcom/camss/camss-vfe.c
> +++ b/drivers/media/platform/qcom/camss/camss-vfe.c
> @@ -437,6 +437,20 @@ void vfe_isr_reset_ack(struct vfe_device *vfe)
> complete(&vfe->reset_complete);
> }
>
> +static int vfe_match_clock_names(struct vfe_device *vfe,
> + struct camss_clock *clock)
> +{
> + char vfe_name[CAMSS_RES_MAX];
> + char vfe_lite_name[CAMSS_RES_MAX];
> +
> + snprintf(vfe_name, sizeof(vfe_name), "vfe%d", vfe->id);
> + snprintf(vfe_lite_name, sizeof(vfe_lite_name), "vfe_lite%d", vfe->id);
> +
> + return (!strcmp(clock->name, vfe_name) ||
> + !strcmp(clock->name, vfe_lite_name) ||
> + !strcmp(clock->name, "vfe_lite"));

The code below will match "vfe0", "vfe1" and "vfe_lite", which the code
here matches "vfe%d", "vfe_life%d" and "vfe_lite". The commit message
doesn't explain why you can restrict the clock name to "vfe%d" instead
of matching both "vfe0" and "vfe1". I could try to guess, but it's
better to clarify it in the commit message.

> +}
> +
> /*
> * vfe_set_clock_rates - Calculate and set clock rates on VFE module
> * @vfe: VFE device
> @@ -460,9 +474,7 @@ static int vfe_set_clock_rates(struct vfe_device *vfe)
> for (i = 0; i < vfe->nclocks; i++) {
> struct camss_clock *clock = &vfe->clock[i];
>
> - if (!strcmp(clock->name, "vfe0") ||
> - !strcmp(clock->name, "vfe1") ||
> - !strcmp(clock->name, "vfe_lite")) {
> + if (vfe_match_clock_names(vfe, clock)) {
> u64 min_rate = 0;
> long rate;
>
> @@ -543,9 +555,7 @@ static int vfe_check_clock_rates(struct vfe_device *vfe)
> for (i = 0; i < vfe->nclocks; i++) {
> struct camss_clock *clock = &vfe->clock[i];
>
> - if (!strcmp(clock->name, "vfe0") ||
> - !strcmp(clock->name, "vfe1") ||
> - !strcmp(clock->name, "vfe_lite")) {
> + if (vfe_match_clock_names(vfe, clock)) {
> u64 min_rate = 0;
> unsigned long rate;
>

--
Regards,

Laurent Pinchart