From e4d9e513dedb5ac4e166c1053314fa935ddecc8c Mon Sep 17 00:00:00 2001 From: Mengdong Lin Date: Thu, 3 Jul 2014 17:02:23 +0800 Subject: ALSA: hda - restore BCLK M/N value as per CDCLK for HSW/BDW display HDA controller 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 Cc: Signed-off-by: Takashi Iwai --- sound/pci/hda/hda_i915.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) (limited to 'sound/pci/hda/hda_i915.c') diff --git a/sound/pci/hda/hda_i915.c b/sound/pci/hda/hda_i915.c index e9e8a4a4a9a1..8b4940ba33d6 100644 --- a/sound/pci/hda/hda_i915.c +++ b/sound/pci/hda/hda_i915.c @@ -20,10 +20,20 @@ #include #include #include +#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; } -- cgit v1.2.3