Re: [PATCH 1/4] pinctrl: sh-pfc: r8a7790: add pin definitions for the I2C3 interface

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Guennadi,

Thank you for the patch.

On Monday 09 September 2013 18:03:53 Guennadi Liakhovetski wrote:
> There are four I2C interfaces on r8a7790, each of them can be connected to
> one of the two respective I2C controllers, e.g. interface #0 can be
> configured to work with I2C0 or with IIC0. Additionally some of those
> interfaces can also use one of several pin sets. Interface #3 is special,
> because it can be used in automatic mode for DVFS. It only has one set
> of pins available and those pins cannot be used for anything else, they
> also lack the GPIO function.
> 
> This patch uses the sh-pfc ability to configure pins, not associated with
> GPIOs and adds support for I2C3 to the r8a7790 PFC set up.

Ulrich Hecht sent a patch titled "sh-pfc: r8a7790: Add I2C pin groups and 
functions" that added pin groups for I2C1 and I2C2. The patch is available 
from

	git://linuxtv.org/pinchartl/fbdev.git pinmux/next

If you need to resubmit this patch due to my comments below, could you please 
rebase it on top of that branch ?

> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
> ---
>  drivers/pinctrl/sh-pfc/pfc-r8a7790.c |   28 ++++++++++++++++++++++++++++
>  1 files changed, 28 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/pinctrl/sh-pfc/pfc-r8a7790.c
> b/drivers/pinctrl/sh-pfc/pfc-r8a7790.c index 64fcc006..c3c4d9b 100644
> --- a/drivers/pinctrl/sh-pfc/pfc-r8a7790.c
> +++ b/drivers/pinctrl/sh-pfc/pfc-r8a7790.c
> @@ -781,6 +781,8 @@ enum {
>  	ADICS_SAMP_MARK, DU2_CDE_MARK, QPOLB_MARK, SCIFA2_RXD_B_MARK,
>  	USB1_PWEN_MARK, AUDIO_CLKOUT_D_MARK, USB1_OVC_MARK,
>  	TCLK1_B_MARK,
> +
> +	I2C3_SCL_MARK, I2C3_SDA_MARK,
>  	PINMUX_MARK_END,
>  };
> 
> @@ -1719,10 +1721,22 @@ static const u16 pinmux_data[] = {
>  	PINMUX_IPSR_DATA(IP16_6, AUDIO_CLKOUT_D),
>  	PINMUX_IPSR_DATA(IP16_7, USB1_OVC),
>  	PINMUX_IPSR_MODSEL_DATA(IP16_7, TCLK1_B, SEL_TMU1_1),
> +
> +	PINMUX_DATA(I2C3_SCL_MARK, FN_SEL_IICDVFS_1),
> +	PINMUX_DATA(I2C3_SDA_MARK, FN_SEL_IICDVFS_1),

You introduce a way to mux the I2C3 function on those two pins, but no way to 
select the IICDVFS back. I don't think it's an issue, we can always add that 
later when (if) needed. Linus, is that fine with you ?

>  };
> 
> +/* R8A7790 has 6 banks with 32 GPIOs in each = 192 GPIOs */
> +#define ROW_GROUP_A(r) ('Z' - 'A' + 1 + (r))
> +#define PIN_NUMBER(r, c) (((r) - 'A') * 16 + (c) + 200)

The BGA package has 31 columns, shouldn't you multiply the row number by 31 
instead of 16 ?

As we have 192 GPIOs, shouldn't you use an offset of 192 instead of 200 ? This 
doesn't matter too much I guess.

> +#define PIN_A_NUMBER(r, c) PIN_NUMBER(ROW_GROUP_A(r), c)
> +
>  static struct sh_pfc_pin pinmux_pins[] = {
>  	PINMUX_GPIO_GP_ALL(),
> +
> +	/* Pins not associated with a GPIO port */
> +	SH_PFC_PIN_NAMED(ROW_GROUP_A('J'), 15, AJ15),
> +	SH_PFC_PIN_NAMED(ROW_GROUP_A('H'), 15, AH15),
>  };
> 
>  /* - DU RGB
> ----------------------------------------------------------------- */ @@
> -1990,6 +2004,14 @@ static const unsigned int hscif1_ctrl_b_pins[] = {
> static const unsigned int hscif1_ctrl_b_mux[] = {
>  	HRTS1_N_B_MARK, HCTS1_N_B_MARK,
>  };
> +/* - I2C3
> ------------------------------------------------------------------- */
> +static const unsigned int i2c3_pins[] = {
> +	/* SCL, SDA */
> +	PIN_A_NUMBER('J', 15), PIN_A_NUMBER('H', 15),
> +};
> +static const unsigned int i2c3_mux[] = {
> +	I2C3_SCL_MARK, I2C3_SDA_MARK,
> +};
>  /* - INTC
> ------------------------------------------------------------------- */
> static const unsigned int intc_irq0_pins[] = {
>  	/* IRQ */
> @@ -3047,6 +3069,7 @@ static const struct sh_pfc_pin_group pinmux_groups[] =
> { SH_PFC_PIN_GROUP(hscif1_data_b),
>  	SH_PFC_PIN_GROUP(hscif1_clk_b),
>  	SH_PFC_PIN_GROUP(hscif1_ctrl_b),
> +	SH_PFC_PIN_GROUP(i2c3),
>  	SH_PFC_PIN_GROUP(intc_irq0),
>  	SH_PFC_PIN_GROUP(intc_irq1),
>  	SH_PFC_PIN_GROUP(intc_irq2),
> @@ -3243,6 +3266,10 @@ static const char * const hscif1_groups[] = {
>  	"hscif1_ctrl_b",
>  };
> 
> +static const char * const i2c3_groups[] = {
> +	"i2c3",
> +};
> +
>  static const char * const intc_groups[] = {
>  	"intc_irq0",
>  	"intc_irq1",
> @@ -3469,6 +3496,7 @@ static const struct sh_pfc_function pinmux_functions[]
> = { SH_PFC_FUNCTION(eth),
>  	SH_PFC_FUNCTION(hscif0),
>  	SH_PFC_FUNCTION(hscif1),
> +	SH_PFC_FUNCTION(i2c3),
>  	SH_PFC_FUNCTION(intc),
>  	SH_PFC_FUNCTION(mmc0),
>  	SH_PFC_FUNCTION(mmc1),
-- 
Regards,

Laurent Pinchart