[PATCH 17/20] video: msm: Prevent framebuffer glitch during initialization

From: Carl Vanderlip
Date: Fri Mar 18 2011 - 18:00:00 EST


Holds a reference to the mdp_clk until lateinit, and moves the frambuffer
initialization to device_init. The framebuffer lcdc driver will grab a
reference to mdp_clk, which prevents the clock from being disabled by
clock_late_init.

Authors:
Dima Zavin <dima@xxxxxxxxxxx>
Rebecca Schultz Zavin <rebecca@xxxxxxxxxxx>
Colin Cross <ccross@xxxxxxxxxxx>

Signed-off-by: Carl Vanderlip <carlv@xxxxxxxxxxxxxx>
---
drivers/video/msm/mdp.c | 10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/drivers/video/msm/mdp.c b/drivers/video/msm/mdp.c
index 0bb19fa..b3f334ad 100644
--- a/drivers/video/msm/mdp.c
+++ b/drivers/video/msm/mdp.c
@@ -38,6 +38,7 @@ struct class *mdp_class;

static DECLARE_WAIT_QUEUE_HEAD(mdp_ppp_waitqueue);
static unsigned int mdp_irq_mask;
+struct clk *mdp_clk_to_disable_later;
DEFINE_MUTEX(mdp_mutex);

static int locked_enable_mdp_irq(struct mdp_info *mdp, uint32_t mask)
@@ -670,6 +671,7 @@ int mdp_probe(struct platform_device *pdev)
disable_irq(mdp->irq);

clk_enable(mdp->clk);
+ mdp_clk_to_disable_later = mdp->clk;
mdp_hw_init(mdp);

/* register mdp device */
@@ -706,6 +708,13 @@ static struct platform_driver msm_mdp_driver = {
.driver = {.name = "msm_mdp"},
};

+static int __init mdp_lateinit(void)
+{
+ if (mdp_clk_to_disable_later)
+ clk_disable(mdp_clk_to_disable_later);
+ return 0;
+}
+
static int __init mdp_init(void)
{
mdp_class = class_create(THIS_MODULE, "msm_mdp");
@@ -717,3 +726,4 @@ static int __init mdp_init(void)
}

subsys_initcall(mdp_init);
+late_initcall(mdp_lateinit);
--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

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