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Diffstat (limited to 'sound/pci/hda/hda_i915.c')
-rw-r--r--sound/pci/hda/hda_i915.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/sound/pci/hda/hda_i915.c b/sound/pci/hda/hda_i915.c
index e9e8a4a..d4d0375 100644
--- a/sound/pci/hda/hda_i915.c
+++ b/sound/pci/hda/hda_i915.c
@@ -20,10 +20,20 @@
#include <linux/module.h>
#include <sound/core.h>
#include <drm/i915_powerwell.h>
+#include "hda_priv.h"
#include "hda_i915.h"
+/* Intel HSW/BDW display HDA controller Extended Mode registers.
+ * EM4 (M value) and EM5 (N Value) are used to convert CDClk (Core Display
+ * Clock) to 24MHz BCLK: BCLK = CDCLK * M / N
+ * The values will be lost when the display power well is disabled.
+ */
+#define AZX_REG_EM4 0x100c
+#define AZX_REG_EM5 0x1010
+
static int (*get_power)(void);
static int (*put_power)(void);
+static int (*get_cdclk)(void);
int hda_display_power(bool enable)
{
@@ -38,6 +48,43 @@ int hda_display_power(bool enable)
return put_power();
}
+void haswell_set_bclk(struct azx *chip)
+{
+ int cdclk_freq;
+ unsigned int bclk_m, bclk_n;
+
+ if (!get_cdclk)
+ return;
+
+ cdclk_freq = get_cdclk();
+ switch (cdclk_freq) {
+ case 337500:
+ bclk_m = 16;
+ bclk_n = 225;
+ break;
+
+ case 450000:
+ default: /* default CDCLK 450MHz */
+ bclk_m = 4;
+ bclk_n = 75;
+ break;
+
+ case 540000:
+ bclk_m = 4;
+ bclk_n = 90;
+ break;
+
+ case 675000:
+ bclk_m = 8;
+ bclk_n = 225;
+ break;
+ }
+
+ azx_writew(chip, EM4, bclk_m);
+ azx_writew(chip, EM5, bclk_n);
+}
+
+
int hda_i915_init(void)
{
int err = 0;
@@ -55,6 +102,10 @@ int hda_i915_init(void)
return -ENODEV;
}
+ get_cdclk = symbol_request(i915_get_cdclk_freq);
+ if (!get_cdclk) /* may have abnormal BCLK and audio playback rate */
+ pr_warn("hda-i915: get_cdclk symbol get fail\n");
+
pr_debug("HDA driver get symbol successfully from i915 module\n");
return err;
@@ -70,6 +121,10 @@ int hda_i915_exit(void)
symbol_put(i915_release_power_well);
put_power = NULL;
}
+ if (get_cdclk) {
+ symbol_put(i915_get_cdclk_freq);
+ get_cdclk = NULL;
+ }
return 0;
}
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