[alsa-devel] [PATCH v3 2/2] ALSA: hda - restore BCLK M/N value as per CDCLK for HSW/BDW display HDA controller
mengdong.lin at intel.com
mengdong.lin at intel.com
Thu Jul 3 11:02:23 CEST 2014
From: Mengdong Lin <mengdong.lin at intel.com>
For HSW/BDW display HD-A controller, hda_set_bclk() is defined to set BCLK
by programming the M/N values as per the core display clock (CDCLK) queried from
i915 display driver.
And the audio driver will also set BCLK in azx_first_init() since the display
driver can turn off the shared power in boot phase if only eDP is connected
and M/N values will be lost and must be reprogrammed.
Signed-off-by: Mengdong Lin <mengdong.lin at intel.com>
diff --git a/sound/pci/hda/hda_i915.c b/sound/pci/hda/hda_i915.c
index e9e8a4a..8b4940b 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 ICH6_REG_EM4 0x100c
+#define ICH6_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;
}
diff --git a/sound/pci/hda/hda_i915.h b/sound/pci/hda/hda_i915.h
index bfd835f..e6072c6 100644
--- a/sound/pci/hda/hda_i915.h
+++ b/sound/pci/hda/hda_i915.h
@@ -18,10 +18,12 @@
#ifdef CONFIG_SND_HDA_I915
int hda_display_power(bool enable);
+void haswell_set_bclk(struct azx *chip);
int hda_i915_init(void);
int hda_i915_exit(void);
#else
static inline int hda_display_power(bool enable) { return 0; }
+static inline void haswell_set_bclk(struct azx *chip) { return; }
static inline int hda_i915_init(void)
{
return -ENODEV;
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 25753db..b6b4e71 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -62,9 +62,9 @@
#include <linux/vga_switcheroo.h>
#include <linux/firmware.h>
#include "hda_codec.h"
-#include "hda_i915.h"
#include "hda_controller.h"
#include "hda_priv.h"
+#include "hda_i915.h"
static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
@@ -288,21 +288,8 @@ static char *driver_short_names[] = {
[AZX_DRIVER_GENERIC] = "HD-Audio Generic",
};
-
-/* 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 ICH6_REG_EM4 0x100c
-#define ICH6_REG_EM5 0x1010
-
struct hda_intel {
struct azx chip;
-
- /* HSW/BDW display HDA controller to restore BCLK from CDCLK */
- unsigned int bclk_m;
- unsigned int bclk_n;
};
@@ -598,22 +585,6 @@ static int param_set_xint(const char *val, const struct kernel_param *kp)
#define azx_del_card_list(chip) /* NOP */
#endif /* CONFIG_PM */
-static void haswell_save_bclk(struct azx *chip)
-{
- struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
-
- hda->bclk_m = azx_readw(chip, EM4);
- hda->bclk_n = azx_readw(chip, EM5);
-}
-
-static void haswell_restore_bclk(struct azx *chip)
-{
- struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
-
- azx_writew(chip, EM4, hda->bclk_m);
- azx_writew(chip, EM5, hda->bclk_n);
-}
-
#if defined(CONFIG_PM_SLEEP) || defined(SUPPORT_VGA_SWITCHEROO)
/*
* power management
@@ -641,12 +612,6 @@ static int azx_suspend(struct device *dev)
chip->irq = -1;
}
- /* Save BCLK M/N values before they become invalid in D3.
- * Will test if display power well can be released now.
- */
- if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
- haswell_save_bclk(chip);
-
if (chip->msi)
pci_disable_msi(chip->pci);
pci_disable_device(pci);
@@ -668,7 +633,7 @@ static int azx_resume(struct device *dev)
if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
hda_display_power(true);
- haswell_restore_bclk(chip);
+ haswell_set_bclk(chip);
}
pci_set_power_state(pci, PCI_D0);
pci_restore_state(pci);
@@ -713,10 +678,9 @@ static int azx_runtime_suspend(struct device *dev)
azx_stop_chip(chip);
azx_enter_link_reset(chip);
azx_clear_irq_pending(chip);
- if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
- haswell_save_bclk(chip);
+ if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
hda_display_power(false);
- }
+
return 0;
}
@@ -736,7 +700,7 @@ static int azx_runtime_resume(struct device *dev)
if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
hda_display_power(true);
- haswell_restore_bclk(chip);
+ haswell_set_bclk(chip);
}
/* Read STATESTS before controller reset */
@@ -1426,6 +1390,10 @@ static int azx_first_init(struct azx *chip)
/* initialize chip */
azx_init_pci(chip);
+
+ if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
+ haswell_set_bclk(chip);
+
azx_init_chip(chip, (probe_only[dev] & 2) == 0);
/* codec detection */
--
1.8.1.2
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