[PATCH v3 3/3] drm/bridge: it6505: Add MCCS support

[Dmitry Baryshkov]

On Tue, Sep 24, 2024 at 03:52:34AM GMT, Hermes.Wu at ite.com.tw wrote:
> >On Mon, Sep 23, 2024 at 05:48:29PM GMT, Hermes Wu wrote:
> >> From: Hermes Wu <Hermes.wu at ite.com.tw>
> >> 
> >> Changes in v3:
> >>  -remove non used definition for aux i2x cmd reply
> >> 
> >> Add Aux-I2C functionality to support MCCS.
> >> 
> >> Signed-off-by: Hermes Wu <Hermes.wu at ite.com.tw>
> >> ---
> >>  drivers/gpu/drm/bridge/ite-it6505.c | 174 
> >> +++++++++++++++++++++++++++-
> >>  1 file changed, 172 insertions(+), 2 deletions(-)
> >> 
> >> diff --git a/drivers/gpu/drm/bridge/ite-it6505.c 
> >> b/drivers/gpu/drm/bridge/ite-it6505.c
> >> index 156440c6517e..5aedc5570739 100644
> >> --- a/drivers/gpu/drm/bridge/ite-it6505.c
> >> +++ b/drivers/gpu/drm/bridge/ite-it6505.c
> >> @@ -125,6 +125,9 @@
> >>  #define REG_AUX_ADR_16_19 0x26
> >>  #define REG_AUX_OUT_DATA0 0x27
> >>  
> >> +#define REG_AUX_I2C_ADR 0x25
> >> +#define REG_AUX_I2C_OP 0x26
> >> +
> >
> >Are these registers CMD-specific? Because I see that you already have defines for 0x25 and 0x26.
> >
> 
> The AUX packet i2c into aux transfer frames,
> and I think it's easier to understand how it6505_aux_i2c_operation() packet i2c request into aux frame.

I'm really sorry, but I don't think I can parse this or how this answers
my question. If for the user I2C a part of the register space gets
repurposed, please comment that before the defines (and maybe separate
such defines so that it's obvious to anybody reading the driver).

> 
> >>  #define REG_AUX_CMD_REQ 0x2B
> >>  #define AUX_BUSY BIT(5)
> >>  
> >> @@ -266,6 +269,19 @@
> >>  #define REG_SSC_CTRL1 0x189
> >>  #define REG_SSC_CTRL2 0x18A
> >>  
> >> +#define REG_AUX_USER_CTRL 0x190
> >> +#define EN_USER_AUX BIT(0)
> >> +#define USER_AUX_DONE BIT(1)
> >> +#define AUX_EVENT BIT(4)
> >> +
> >> +#define REG_AUX_USER_DATA_REC 0x191
> >> +#define M_AUX_IN_REC   0xF0
> >> +#define M_AUX_OUT_REC  0x0F
> >> +
> >> +#define REG_AUX_USER_TXB 0x190
> >
> >And two defines for 0x190 too.
> >
> >> +#define REG_AUX_USER_REPLY 0x19A
> >> +#define REG_AUX_USER_RXB(n) (n + 0x19B)
> >> +
> >>  #define RBR DP_LINK_BW_1_62
> >>  #define HBR DP_LINK_BW_2_7
> >>  #define HBR2 DP_LINK_BW_5_4

-- 
With best wishes
Dmitry