Hi Russell,
On 03/30/2015 03:40 PM, Russell King wrote:
> Clean up hdmi_set_clk_regenerator() by allowing it to take the audio
> sample rate and ratio directly, rather than hiding it inside the
> function. Raise the unsupported pixel clock/sample rate message from
> debug to error level as this results in audio not working correctly.
>
> Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
> ---
> drivers/gpu/drm/bridge/dw_hdmi.c | 32 +++++++++++++++-----------------
> 1 file changed, 15 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c
> b/drivers/gpu/drm/bridge/dw_hdmi.c
> index cca1c3d165e2..49df6c8c4ea8 100644
> --- a/drivers/gpu/drm/bridge/dw_hdmi.c
> +++ b/drivers/gpu/drm/bridge/dw_hdmi.c
> @@ -335,39 +335,37 @@ static unsigned int hdmi_compute_cts(unsigned int freq,
> unsigned long pixel_clk,
> }
>
> static void hdmi_set_clk_regenerator(struct dw_hdmi *hdmi,
> - unsigned long pixel_clk)
> + unsigned long pixel_clk, unsigned int sample_rate, unsigned int ratio)
> {
> - unsigned int clk_n, clk_cts;
> + unsigned int n, cts;
>
> - clk_n = hdmi_compute_n(hdmi->sample_rate, pixel_clk,
> - hdmi->ratio);
> - clk_cts = hdmi_compute_cts(hdmi->sample_rate, pixel_clk,
> - hdmi->ratio);
> -
> - if (!clk_cts) {
> - dev_dbg(hdmi->dev, "%s: pixel clock not supported: %lu\n",
> - __func__, pixel_clk);
> - return;
> + n = hdmi_compute_n(sample_rate, pixel_clk, ratio);
> + cts = hdmi_compute_cts(sample_rate, pixel_clk, ratio);
> + if (!cts) {
> + dev_err(hdmi->dev,
> + "%s: pixel clock/sample rate not supported: %luMHz /
> %ukHz\n",
> + __func__, pixel_clk, sample_rate);
> }
>
> - dev_dbg(hdmi->dev, "%s: samplerate=%d ratio=%d pixelclk=%lu N=%d
> cts=%d\n",
> - __func__, hdmi->sample_rate, hdmi->ratio,
> - pixel_clk, clk_n, clk_cts);
> + dev_dbg(hdmi->dev, "%s: samplerate=%ukHz ratio=%d pixelclk=%luMHz N=%d
> cts=%d\n",
> + __func__, sample_rate, ratio, pixel_clk, n, cts);
>
> - hdmi_set_cts_n(hdmi, clk_cts, clk_n);
> + hdmi_set_cts_n(hdmi, cts, n);
> }
>
> static void hdmi_init_clk_regenerator(struct dw_hdmi *hdmi)
> {
> mutex_lock(&hdmi->audio_mutex);
> - hdmi_set_clk_regenerator(hdmi, 74250000);
> + hdmi_set_clk_regenerator(hdmi, 74250000, hdmi->sample_rate,
> + hdmi->ratio);
> mutex_unlock(&hdmi->audio_mutex);
> }
>
> static void hdmi_clk_regenerator_update_pixel_clock(struct dw_hdmi *hdmi)
> {
> mutex_lock(&hdmi->audio_mutex);
> - hdmi_set_clk_regenerator(hdmi, hdmi->hdmi_data.video_mode.mpixelclock);
> + hdmi_set_clk_regenerator(hdmi, hdmi->hdmi_data.video_mode.mpixelclock,
> + hdmi->sample_rate, hdmi->ratio);
I'm okay with this change, and also I am preparing that collect N/CTS
setting to an array, like this :
struct n_cts {
unsigned int cts;
unsigned int n;
};
struct tmds_n_cts {
unsigned long tmds;
/* 1 entry each for 32KHz, 44.1KHz, and 48KHz */
struct n_cts n_cts[3];
};
static const struct tmds_n_cts n_cts_table[] = {
{ 25175000, {{ 28125, 4576}, { 31250, 7007}, { 25175, 6144} } },
}
But I am confused by the "hdmi->ratio", this variable was modify to 100
in bind
funciton, then nowhere would change it again. In this case "hdmi->ratio"
seems
an unused variable, can we remove it ?
Best regards.
Yakir Yang
> mutex_unlock(&hdmi->audio_mutex);
> }
>
