drm/i2c: tda998x: power down pre-filter and color conversion

Disabling the pre-filter block of the TDA998x saves 40mW and the colour
conversion block saves 15mW.  As we always disable these two blocks, we
can power these sections of the chip down to save 55mW of unnecessary
power consumption.

Tested-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Brian Starkey <brian.starkey@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
This commit is contained in:
Russell King 2016-11-03 15:19:06 +00:00
parent 3cb43378d8
commit 9476ed2e38

View File

@ -107,6 +107,8 @@ struct tda998x_priv {
# define I2C_MASTER_DIS_FILT (1 << 1)
# define I2C_MASTER_APP_STRT_LAT (1 << 2)
#define REG_FEAT_POWERDOWN REG(0x00, 0x0e) /* read/write */
# define FEAT_POWERDOWN_PREFILT BIT(0)
# define FEAT_POWERDOWN_CSC BIT(1)
# define FEAT_POWERDOWN_SPDIF (1 << 3)
#define REG_INT_FLAGS_0 REG(0x00, 0x0f) /* read/write */
#define REG_INT_FLAGS_1 REG(0x00, 0x10) /* read/write */
@ -1284,6 +1286,7 @@ tda998x_encoder_mode_set(struct drm_encoder *encoder,
/* no pre-filter or interpolator: */
reg_write(priv, REG_HVF_CNTRL_0, HVF_CNTRL_0_PREFIL(0) |
HVF_CNTRL_0_INTPOL(0));
reg_set(priv, REG_FEAT_POWERDOWN, FEAT_POWERDOWN_PREFILT);
reg_write(priv, REG_VIP_CNTRL_5, VIP_CNTRL_5_SP_CNT(0));
reg_write(priv, REG_VIP_CNTRL_4, VIP_CNTRL_4_BLANKIT(0) |
VIP_CNTRL_4_BLC(0));
@ -1306,6 +1309,7 @@ tda998x_encoder_mode_set(struct drm_encoder *encoder,
/* set color matrix bypass flag: */
reg_write(priv, REG_MAT_CONTRL, MAT_CONTRL_MAT_BP |
MAT_CONTRL_MAT_SC(1));
reg_set(priv, REG_FEAT_POWERDOWN, FEAT_POWERDOWN_CSC);
/* set BIAS tmds value: */
reg_write(priv, REG_ANA_GENERAL, 0x09);