[PATCH v2 5/6] drm/rockchip: Improve analogix-dp psr handling

[Yakir Yang]

On 08/17/2016 09:11 AM, Sean Paul wrote:
> Remove the delayed worker, opting instead for the non-delayed
> variety. Also introduce a lock to ensure we don't have races
> with the worker and psr_state. Finally, cancel and wait for
> the worker to finish when disabling the bridge.
>
> Signed-off-by: Sean Paul <seanpaul at chromium.org>
Reviewed-by: Yakir Yang <ykk at rock-chips.com>
> ---
>
> Changes in v2:
> 	- Rebased on https://cgit.freedesktop.org/~seanpaul/dogwood/log/?h=for-next
>
>   drivers/gpu/drm/rockchip/analogix_dp-rockchip.c | 19 ++++++++++++++-----
>   1 file changed, 14 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> index d6d0751..439b933 100644
> --- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> +++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
> @@ -42,7 +42,6 @@
>   
>   #define HIWORD_UPDATE(val, mask)	(val | (mask) << 16)
>   
> -#define PSR_SET_DELAY_TIME		msecs_to_jiffies(10)
>   #define PSR_WAIT_LINE_FLAG_TIMEOUT_MS	100
>   
>   #define to_dp(nm)	container_of(nm, struct rockchip_dp_device, nm)
> @@ -72,7 +71,8 @@ struct rockchip_dp_device {
>   	struct regmap            *grf;
>   	struct reset_control     *rst;
>   
> -	struct delayed_work      psr_work;
> +	struct work_struct	 psr_work;
> +	spinlock_t		 psr_lock;
>   	unsigned int             psr_state;
>   
>   	const struct rockchip_dp_chip_data *data;
> @@ -83,25 +83,29 @@ struct rockchip_dp_device {
>   static void analogix_dp_psr_set(struct drm_encoder *encoder, bool enabled)
>   {
>   	struct rockchip_dp_device *dp = to_dp(encoder);
> +	unsigned long flags;
>   
>   	dev_dbg(dp->dev, "%s PSR...\n", enabled ? "Entry" : "Exit");
>   
> +	spin_lock_irqsave(&dp->psr_lock, flags);
>   	if (enabled)
>   		dp->psr_state = EDP_VSC_PSR_STATE_ACTIVE;
>   	else
>   		dp->psr_state = ~EDP_VSC_PSR_STATE_ACTIVE;
>   
> -	schedule_delayed_work(&dp->psr_work, PSR_SET_DELAY_TIME);
> +	schedule_work(&dp->psr_work);
> +	spin_unlock_irqrestore(&dp->psr_lock, flags);
>   }
>   
>   static void analogix_dp_psr_work(struct work_struct *work)
>   {
>   	struct rockchip_dp_device *dp =
> -				container_of(work, typeof(*dp), psr_work.work);
> +				container_of(work, typeof(*dp), psr_work);
>   	struct drm_crtc *crtc = dp->encoder.crtc;
>   	int psr_state = dp->psr_state;
>   	int vact_end;
>   	int ret;
> +	unsigned long flags;
>   
>   	if (!crtc)
>   		return;
> @@ -115,10 +119,12 @@ static void analogix_dp_psr_work(struct work_struct *work)
>   		return;
>   	}
>   
> +	spin_lock_irqsave(&dp->psr_lock, flags);
>   	if (psr_state == EDP_VSC_PSR_STATE_ACTIVE)
>   		analogix_dp_enable_psr(dp->dev);
>   	else
>   		analogix_dp_disable_psr(dp->dev);
> +	spin_unlock_irqrestore(&dp->psr_lock, flags);
>   }
>   
>   static int rockchip_dp_pre_init(struct rockchip_dp_device *dp)
> @@ -135,6 +141,8 @@ static int rockchip_dp_poweron(struct analogix_dp_plat_data *plat_data)
>   	struct rockchip_dp_device *dp = to_dp(plat_data);
>   	int ret;
>   
> +	cancel_work_sync(&dp->psr_work);
> +
>   	ret = clk_prepare_enable(dp->pclk);
>   	if (ret < 0) {
>   		dev_err(dp->dev, "failed to enable pclk %d\n", ret);
> @@ -390,8 +398,9 @@ static int rockchip_dp_bind(struct device *dev, struct device *master,
>   	dp->plat_data.power_off = rockchip_dp_powerdown;
>   	dp->plat_data.get_modes = rockchip_dp_get_modes;
>   
> +	spin_lock_init(&dp->psr_lock);
>   	dp->psr_state = ~EDP_VSC_PSR_STATE_ACTIVE;
> -	INIT_DELAYED_WORK(&dp->psr_work, analogix_dp_psr_work);
> +	INIT_WORK(&dp->psr_work, analogix_dp_psr_work);
>   
>   	rockchip_drm_psr_register(&dp->encoder, analogix_dp_psr_set);
>