Re: [PATCH 2/2] clk: rs9: Add support for 9FGV0841

[Alexander Stein <alexander.stein@ew.tq-group.com>]

Hi Marek,

thanks for the patch.

Am Sonntag, 5. November 2023, 21:07:59 CET schrieb Marek Vasut:
> This model is similar to 9FGV0441, the DIFx bits start at bit 0 again,
> except this chip has 8 outputs. Adjust rs9_calc_dif() to special-case
> the 9FGV0241 where DIFx bits start at 1. Extract only vendor ID from
> VID register, the top 4 bits are revision ID which are not useful for
> the vendor ID check.
> 
> Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
> ---
> Cc: Alexander Stein <alexander.stein@ew.tq-group.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Geert Uytterhoeven <geert+renesas@glider.be>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
> Cc: Michael Turquette <mturquette@baylibre.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Stephen Boyd <sboyd@kernel.org>
> Cc: devicetree@vger.kernel.org
> Cc: linux-clk@vger.kernel.org
> Cc: linux-renesas-soc@vger.kernel.org
> ---
>  drivers/clk/clk-renesas-pcie.c | 23 +++++++++++++++++++----
>  1 file changed, 19 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/clk/clk-renesas-pcie.c b/drivers/clk/clk-renesas-pcie.c
> index 6606aba253c5..f8dd79b18d5a 100644
> --- a/drivers/clk/clk-renesas-pcie.c
> +++ b/drivers/clk/clk-renesas-pcie.c
> @@ -7,6 +7,7 @@
>   * Currently supported:
>   *   - 9FGV0241
>   *   - 9FGV0441
> + *   - 9FGV0841
>   *
>   * Copyright (C) 2022 Marek Vasut <marex@denx.de>
>   */
> @@ -42,6 +43,7 @@
>  #define RS9_REG_DID				0x6
>  #define RS9_REG_BCP				0x7
> 
> +#define RS9_REG_VID_MASK			GENMASK(3, 0)
>  #define RS9_REG_VID_IDT				0x01
> 
>  #define RS9_REG_DID_TYPE_FGV			(0x0 << 
RS9_REG_DID_TYPE_SHIFT)
> @@ -53,6 +55,7 @@
>  enum rs9_model {
>  	RENESAS_9FGV0241,
>  	RENESAS_9FGV0441,
> +	RENESAS_9FGV0841,
>  };
> 
>  /* Structure to describe features of a particular 9-series model */
> @@ -162,12 +165,15 @@ static u8 rs9_calc_dif(const struct rs9_driver_data
> *rs9, int idx) {
>  	enum rs9_model model = rs9->chip_info->model;
> 
> +	/*
> +	 * On 9FGV0241, the DIF OE0 is BIT(1) and DIF OE(1) is BIT(2),
> +	 * on 9FGV0441 and 9FGV0841 the DIF OE0 is BIT(0) and so on.
> +	 * Increment the index in the 9FGV0241 special case here.
> +	 */
>  	if (model == RENESAS_9FGV0241)
> -		return BIT(idx + 1);
> -	else if (model == RENESAS_9FGV0441)
> -		return BIT(idx);
> +		idx++;
> 
> -	return 0;
> +	return BIT(idx);
>  }
> 
>  static int rs9_get_output_config(struct rs9_driver_data *rs9, int idx)
> @@ -333,6 +339,7 @@ static int rs9_probe(struct i2c_client *client)
>  	if (ret < 0)
>  		return ret;
> 
> +	vid &= RS9_REG_VID_MASK;

This is an independent change from 9FGV0841 support. So please split it into a 
separate patch.
Despite that adding the support looks good. I don't have a strong opinion 
regarding the model check as raised by Biju.

Best regards,
Alexander

>  	if (vid != RS9_REG_VID_IDT || did != rs9->chip_info->did)
>  		return dev_err_probe(&client->dev, -ENODEV,
>  				     "Incorrect VID/DID: %#02x, %#02x. 
Expected %#02x, %#02x\n",
> @@ -391,9 +398,16 @@ static const struct rs9_chip_info renesas_9fgv0441_info
> = { .did		= RS9_REG_DID_TYPE_FGV | 0x04,
>  };
> 
> +static const struct rs9_chip_info renesas_9fgv0841_info = {
> +	.model		= RENESAS_9FGV0841,
> +	.num_clks	= 8,
> +	.did		= RS9_REG_DID_TYPE_FGV | 0x08,
> +};
> +
>  static const struct i2c_device_id rs9_id[] = {
>  	{ "9fgv0241", .driver_data = (kernel_ulong_t)&renesas_9fgv0241_info 
},
>  	{ "9fgv0441", .driver_data = (kernel_ulong_t)&renesas_9fgv0441_info 
},
> +	{ "9fgv0841", .driver_data = (kernel_ulong_t)&renesas_9fgv0841_info 
},
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(i2c, rs9_id);
> @@ -401,6 +415,7 @@ MODULE_DEVICE_TABLE(i2c, rs9_id);
>  static const struct of_device_id clk_rs9_of_match[] = {
>  	{ .compatible = "renesas,9fgv0241", .data = &renesas_9fgv0241_info 
},
>  	{ .compatible = "renesas,9fgv0441", .data = &renesas_9fgv0441_info 
},
> +	{ .compatible = "renesas,9fgv0841", .data = &renesas_9fgv0841_info 
},
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(of, clk_rs9_of_match);


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