[3.13.y-ckt stable] Patch "drm/i915: provide interface for audio driver to query cdclk" has been added to staging queue
Kamal Mostafa
kamal at canonical.com
Tue Nov 25 20:35:18 UTC 2014
This is a note to let you know that I have just added a patch titled
drm/i915: provide interface for audio driver to query cdclk
to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree
which can be found at:
http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue
This patch is scheduled to be released in version 3.13.11-ckt12.
If you, or anyone else, feels it should not be added to this tree, please
reply to this email.
For more information about the 3.13.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable
Thanks.
-Kamal
------
>From 5a7673211c1e76eb536b5a4623a57479176928e4 Mon Sep 17 00:00:00 2001
From: Jani Nikula <jani.nikula at intel.com>
Date: Fri, 4 Jul 2014 10:00:37 +0800
Subject: drm/i915: provide interface for audio driver to query cdclk
commit c149dcb5c60bfea8871f16dfcc0690255eeb825f upstream.
For Haswell and Broadwell, if the display power well has been disabled,
the display audio controller divider values EM4 M VALUE and EM5 N VALUE
will have been lost. The CDCLK frequency is required for reprogramming them
to generate 24MHz HD-A link BCLK. So provide a private interface for the
audio driver to query CDCLK.
This is a stopgap solution until a more generic interface between audio
and display drivers has been implemented.
Signed-off-by: Jani Nikula <jani.nikula at intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau at intel.com>
Signed-off-by: Mengdong Lin <mengdong.lin at intel.com>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
drivers/gpu/drm/i915/intel_pm.c | 20 ++++++++++++++++++++
include/drm/i915_powerwell.h | 1 +
2 files changed, 21 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 839e581..ba51112 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5884,6 +5884,26 @@ int i915_release_power_well(void)
}
EXPORT_SYMBOL_GPL(i915_release_power_well);
+/*
+ * Private interface for the audio driver to get CDCLK in kHz.
+ *
+ * Caller must request power well using i915_request_power_well() prior to
+ * making the call.
+ */
+int i915_get_cdclk_freq(void)
+{
+ struct drm_i915_private *dev_priv;
+
+ if (!hsw_pwr)
+ return -ENODEV;
+
+ dev_priv = container_of(hsw_pwr, struct drm_i915_private,
+ power_domains);
+
+ return intel_ddi_get_cdclk_freq(dev_priv);
+}
+EXPORT_SYMBOL_GPL(i915_get_cdclk_freq);
+
int intel_power_domains_init(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
diff --git a/include/drm/i915_powerwell.h b/include/drm/i915_powerwell.h
index 2baba99..baa6f11 100644
--- a/include/drm/i915_powerwell.h
+++ b/include/drm/i915_powerwell.h
@@ -32,5 +32,6 @@
/* For use by hda_i915 driver */
extern int i915_request_power_well(void);
extern int i915_release_power_well(void);
+extern int i915_get_cdclk_freq(void);
#endif /* _I915_POWERWELL_H_ */
--
1.9.1
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