RE: [PATCH 4/5] i2c: riic: Pass register offsets and chip details as OF data

From: Biju Das <biju.das.jz@bp.renesas.com>
To: Prabhakar <prabhakar.csengg@gmail.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Chris Brandt <Chris.Brandt@renesas.com>,
	Andi Shyti <andi.shyti@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Magnus Damm <magnus.damm@gmail.com>,
	Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: "linux-renesas-soc@vger.kernel.org"
	<linux-renesas-soc@vger.kernel.org>,
	"linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Fabrizio Castro <fabrizio.castro.jz@renesas.com>,
	Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com>
Subject: RE: [PATCH 4/5] i2c: riic: Pass register offsets and chip details as OF data
Date: Fri, 8 Mar 2024 17:36:32 +0000	[thread overview]
Message-ID: <OSAPR01MB1587CFE774834B31820E7D5486272@OSAPR01MB1587.jpnprd01.prod.outlook.com> (raw)
In-Reply-To: <20240308172726.225357-5-prabhakar.mahadev-lad.rj@bp.renesas.com>

Hi Prabhakar,

Thanks for the patch.

> -----Original Message-----
> From: Prabhakar <prabhakar.csengg@gmail.com>
> Sent: Friday, March 8, 2024 5:27 PM
> Subject: [PATCH 4/5] i2c: riic: Pass register offsets and chip details as OF data
> 
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> 
> With an increasing number of SoCs reusing this driver, each with slight variations in the RIIC IP, it
> becomes necessary to support passing these details as OF data. This approach simplifies the extension
> of the driver for other SoCs.
> 
> This patch lays the groundwork for adding support for the Renesas RZ/V2H SoC.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> Reviewed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
> ---
>  drivers/i2c/busses/i2c-riic.c | 59 ++++++++++++++++++++++++++---------
>  1 file changed, 44 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-riic.c b/drivers/i2c/busses/i2c-riic.c index
> 49a12f1ecdf9..3398d639b754 100644
> --- a/drivers/i2c/busses/i2c-riic.c
> +++ b/drivers/i2c/busses/i2c-riic.c
> @@ -46,18 +46,6 @@
>  #include <linux/pm_runtime.h>
>  #include <linux/reset.h>
> 
> -#define RIIC_ICCR1	0x00
> -#define RIIC_ICCR2	0x04
> -#define RIIC_ICMR1	0x08
> -#define RIIC_ICMR3	0x10
> -#define RIIC_ICSER	0x18
> -#define RIIC_ICIER	0x1c
> -#define RIIC_ICSR2	0x24
> -#define RIIC_ICBRL	0x34
> -#define RIIC_ICBRH	0x38
> -#define RIIC_ICDRT	0x3c
> -#define RIIC_ICDRR	0x40
> -
>  #define ICCR1_ICE	0x80
>  #define ICCR1_IICRST	0x40
>  #define ICCR1_SOWP	0x10
> @@ -87,6 +75,13 @@
> 
>  #define RIIC_INIT_MSG	-1
> 
> +#define RIIC_RZ_A_TYPE	0

> +
> +struct riic_of_data {
> +	u8 family;

Do you need family as compatible have this information?

> +	u8 regs[];
> +};
> +
>  struct riic_dev {
>  	void __iomem *base;
>  	u8 *buf;
> @@ -94,6 +89,7 @@ struct riic_dev {
>  	int bytes_left;
>  	int err;
>  	int is_last;
> +	const struct riic_of_data *info;
>  	struct completion msg_done;
>  	struct i2c_adapter adapter;
>  	struct clk *clk;
> @@ -105,14 +101,28 @@ struct riic_irq_desc {
>  	char *name;
>  };
> 
> +enum riic_reg_list {
> +	RIIC_ICCR1 = 0,
> +	RIIC_ICCR2,
> +	RIIC_ICMR1,
> +	RIIC_ICMR3,
> +	RIIC_ICSER,
> +	RIIC_ICIER,
> +	RIIC_ICSR2,
> +	RIIC_ICBRL,
> +	RIIC_ICBRH,
> +	RIIC_ICDRT,
> +	RIIC_ICDRR,
> +};
> +
>  static inline void riic_writeb_reg(u8 val, struct riic_dev *riic, u8 offset)  {
> -	writeb(val, riic->base + offset);
> +	writeb(val, riic->base + riic->info->regs[offset]);
>  }
> 
>  static inline u8 riic_readb_reg(struct riic_dev *riic, u8 offset)  {
> -	return readb(riic->base + offset);
> +	return readb(riic->base + riic->info->regs[offset]);
>  }
> 
>  static inline void riic_clear_set_bit(struct riic_dev *riic, u8 clear, u8 set, u8 reg) @@ -453,6
> +463,8 @@ static int riic_i2c_probe(struct platform_device *pdev)
>  		}
>  	}
> 
> +	riic->info = of_device_get_match_data(&pdev->dev);
> +
>  	adap = &riic->adapter;
>  	i2c_set_adapdata(adap, riic);
>  	strscpy(adap->name, "Renesas RIIC adapter", sizeof(adap->name)); @@ -497,8 +509,25 @@ static void
> riic_i2c_remove(struct platform_device *pdev)
>  	pm_runtime_disable(&pdev->dev);
>  }
> 
> +static const struct riic_of_data riic_rz_a_info = {
> +	.family = RIIC_RZ_A_TYPE,
> +	.regs = {
> +		[RIIC_ICCR1] = 0x00,
> +		[RIIC_ICCR2] = 0x04,
> +		[RIIC_ICMR1] = 0x08,
> +		[RIIC_ICMR3] = 0x10,
> +		[RIIC_ICSER] = 0x18,
> +		[RIIC_ICIER] = 0x1c,
> +		[RIIC_ICSR2] = 0x24,
> +		[RIIC_ICBRL] = 0x34,
> +		[RIIC_ICBRH] = 0x38,
> +		[RIIC_ICDRT] = 0x3c,
> +		[RIIC_ICDRR] = 0x40,
> +	},
> +};
> +
>  static const struct of_device_id riic_i2c_dt_ids[] = {
> -	{ .compatible = "renesas,riic-rz", },
> +	{ .compatible = "renesas,riic-rz", .data = &riic_rz_a_info },
>  	{ /* Sentinel */ },
>  };
> 
> --
> 2.34.1
> 