Re: [PATCH v8 1/2] spi: Add Renesas R-Car Gen3 RPC-IF SPI controller driver

[Sergei Shtylyov]

Hello!

On 01/28/2019 09:49 AM, Mason Yang wrote:

> Add a driver for Renesas R-Car Gen3 RPC-IF SPI controller.
> 
> Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx>
> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx>
[...]
> diff --git a/drivers/spi/spi-renesas-rpc.c b/drivers/spi/spi-renesas-rpc.c
> new file mode 100644
> index 0000000..ea12017
> --- /dev/null
> +++ b/drivers/spi/spi-renesas-rpc.c
> @@ -0,0 +1,804 @@
[...]
> +static void rpc_spi_hw_init(struct rpc_spi *rpc)
> +{
> +	//
> +	// NOTE: The 0x260 are undocumented bits, but they must be set.
> +	//	RPC_PHYCNT_STRTIM is strobe timing adjustment bit,
> +	//	0x0 : the delay is biggest,
> +	//	0x1 : the delay is 2nd biggest,
> +	//	On H3 ES1.x, the value should be 0, while on others,
> +	//	the value should be 6.
> +	//
> +	regmap_write(rpc->regmap, RPC_PHYCNT, RPC_PHYCNT_CAL |
> +				  RPC_PHYCNT_STRTIM(6) | 0x260);
> +
> +	//
> +	// NOTE: The 0x1511144 are undocumented bits, but they must be set
> +	//       for RPC_PHYOFFSET1.
> +	//	 The 0x31 are undocumented bits, but they must be set
> +	//	 for RPC_PHYOFFSET2.
> +	//
> +	regmap_write(rpc->regmap, RPC_PHYOFFSET1, RPC_PHYOFFSET1_DDRTMG(3) |
> +		     0x1511144);
> +	regmap_write(rpc->regmap, RPC_PHYOFFSET2, 0x31 |
> +		     RPC_PHYOFFSET2_OCTTMG(4));
> +	regmap_write(rpc->regmap, RPC_SSLDR, RPC_SSLDR_SPNDL(7) |
> +		     RPC_SSLDR_SLNDL(7) | RPC_SSLDR_SCKDL(7));
> +	regmap_write(rpc->regmap, RPC_CMNCR, RPC_CMNCR_MD | RPC_CMNCR_SFDE |
> +		     RPC_CMNCR_MOIIO_HIZ | RPC_CMNCR_IOFV_HIZ |
> +		     RPC_CMNCR_BSZ(0));
> +}

   We clearly need runtime PM get/put() calls around this code. Otherwise,
we're dependant on U-Boot leaving the clocks enabled...

[...]

MBR, Sergei