From f853f3daac748daa339bc8b64ba39db82160524a Mon Sep 17 00:00:00 2001 From: Steve Longerbeam Date: Mon, 26 Aug 2013 11:42:09 -0700 Subject: [PATCH] gpu: ipu-v3: Implement use counter for ipu_dc_enable(), ipu_dc_disable() The functions ipu_dc_enable() and ipu_dc_disable() enable/disable the DC globally in the IPU_CONF register, but the DC is used by multiple clients on different DC channels. So make sure to only disable/enable the DC globally based on a use counter. Signed-off-by: Steve Longerbeam Signed-off-by: Philipp Zabel --- drivers/gpu/ipu-v3/ipu-dc.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/ipu-v3/ipu-dc.c b/drivers/gpu/ipu-v3/ipu-dc.c index 2326c752d89b..323203d0503a 100644 --- a/drivers/gpu/ipu-v3/ipu-dc.c +++ b/drivers/gpu/ipu-v3/ipu-dc.c @@ -114,6 +114,7 @@ struct ipu_dc_priv { struct completion comp; int dc_irq; int dp_irq; + int use_count; }; static void dc_link_event(struct ipu_dc *dc, int event, int addr, int priority) @@ -232,7 +233,16 @@ EXPORT_SYMBOL_GPL(ipu_dc_init_sync); void ipu_dc_enable(struct ipu_soc *ipu) { - ipu_module_enable(ipu, IPU_CONF_DC_EN); + struct ipu_dc_priv *priv = ipu->dc_priv; + + mutex_lock(&priv->mutex); + + if (!priv->use_count) + ipu_module_enable(priv->ipu, IPU_CONF_DC_EN); + + priv->use_count++; + + mutex_unlock(&priv->mutex); } EXPORT_SYMBOL_GPL(ipu_dc_enable); @@ -294,7 +304,18 @@ EXPORT_SYMBOL_GPL(ipu_dc_disable_channel); void ipu_dc_disable(struct ipu_soc *ipu) { - ipu_module_disable(ipu, IPU_CONF_DC_EN); + struct ipu_dc_priv *priv = ipu->dc_priv; + + mutex_lock(&priv->mutex); + + priv->use_count--; + if (!priv->use_count) + ipu_module_disable(priv->ipu, IPU_CONF_DC_EN); + + if (priv->use_count < 0) + priv->use_count = 0; + + mutex_unlock(&priv->mutex); } EXPORT_SYMBOL_GPL(ipu_dc_disable); -- 2.11.0