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>
diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c
index ffd87ed..5a97444 100644
--- a/drivers/gpu/drm/i2c/tda998x_drv.c
+++ b/drivers/gpu/drm/i2c/tda998x_drv.c
@@ -107,6 +107,8 @@
# 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 @@
/* 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 @@
/* 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);