Hi Tony,

Thank you for the patch.

On Mon, Mar 25, 2019 at 04:47:43PM -0700, Tony Lindgren wrote:
> If CONFIG_OMAP4_DSS_HDMI_CEC is enabled in .config, deeper SoC idle
> states are blocked because the CEC clock gets always enabled on init.
> 
> Let's fix the issue by moving the CEC clock handling to happen later in
> hdmi_cec_adap_enable() as suggested by Hans Verkuil <hverk...@xs4all.nl>.
> This way the CEC clock gets only enabled when needed. This can be tested
> by doing cec-ctl --playback to enable the CEC, and doing cec-ctl --clear
> to disable it.
> 
> Let's also fix the typo for "divider" in the comments while at it.
> 
> Fixes: 8d7f934df8d8 ("omapdrm: hdmi4_cec: add OMAP4 HDMI CEC support")
> Suggested-by: Hans Verkuil <hverk...@xs4all.nl>
> Cc: Hans Verkuil <hverk...@xs4all.nl>
> Cc: Jyri Sarha <jsa...@ti.com>
> Cc: Laurent Pinchart <laurent.pinch...@ideasonboard.com>
> Signed-off-by: Tony Lindgren <t...@atomide.com>

Reviewed-by: Laurent Pinchart <laurent.pinch...@ideasonboard.com>

> ---
>  drivers/gpu/drm/omapdrm/dss/hdmi4_cec.c | 16 ++++++++++------
>  1 file changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/hdmi4_cec.c 
> b/drivers/gpu/drm/omapdrm/dss/hdmi4_cec.c
> --- a/drivers/gpu/drm/omapdrm/dss/hdmi4_cec.c
> +++ b/drivers/gpu/drm/omapdrm/dss/hdmi4_cec.c
> @@ -169,12 +169,19 @@ static int hdmi_cec_adap_enable(struct cec_adapter 
> *adap, bool enable)
>       struct hdmi_core_data *core = cec_get_drvdata(adap);
>       int temp, err;
>  
> -     if (!enable) {
> +     if (enable) {
> +             /*
> +              * Initialize CEC clock divider: CEC needs 2MHz clock hence
> +              * set the divider to 24 to get 48/24=2MHz clock
> +              */
> +             REG_FLD_MOD(core->wp->base, HDMI_WP_CLK, 0x18, 5, 0);
> +     } else {
>               hdmi_write_reg(core->base, HDMI_CEC_INT_ENABLE_0, 0);
>               hdmi_write_reg(core->base, HDMI_CEC_INT_ENABLE_1, 0);
>               REG_FLD_MOD(core->base, HDMI_CORE_SYS_INTR_UNMASK4, 0, 3, 3);
>               hdmi_wp_clear_irqenable(core->wp, HDMI_IRQ_CORE);
>               hdmi_wp_set_irqstatus(core->wp, HDMI_IRQ_CORE);
> +             REG_FLD_MOD(core->wp->base, HDMI_WP_CLK, 0, 5, 0);
>               hdmi4_core_disable(core);
>               return 0;
>       }
> @@ -333,11 +340,8 @@ int hdmi4_cec_init(struct platform_device *pdev, struct 
> hdmi_core_data *core,
>               return ret;
>       core->wp = wp;
>  
> -     /*
> -      * Initialize CEC clock divider: CEC needs 2MHz clock hence
> -      * set the devider to 24 to get 48/24=2MHz clock
> -      */
> -     REG_FLD_MOD(core->wp->base, HDMI_WP_CLK, 0x18, 5, 0);
> +     /* Disable clock initially, hdmi_cec_adap_enable() manages it */
> +     REG_FLD_MOD(core->wp->base, HDMI_WP_CLK, 0, 5, 0);
>  
>       ret = cec_register_adapter(core->adap, &pdev->dev);
>       if (ret < 0) {

-- 
Regards,

Laurent Pinchart
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