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Message-ID: <50bedd75-bcd6-d7bc-26c0-b8c00f99779a@linaro.org>
Date:   Wed, 9 Aug 2023 16:29:33 +0200
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Subject: Re: [PATCH v2 2/2] rtc: nuvoton: Compatible with NCT3015Y-R and
 NCT3018Y-R
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To:     Mia Lin <mimi05633@gmail.com>, avifishman70@gmail.com,
        tmaimon77@gmail.com, tali.perry1@gmail.com, venture@google.com,
        yuenn@google.com, benjaminfair@google.com, a.zummo@towertech.it,
        alexandre.belloni@bootlin.com, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
        KWLIU@nuvoton.com, JJLIU0@nuvoton.com, KFLIN@nuvoton.com,
        mylin1@nuvoton.com
Cc:     openbmc@lists.ozlabs.org, linux-rtc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230809095112.2836-1-mimi05633@gmail.com>
 <20230809095112.2836-3-mimi05633@gmail.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20230809095112.2836-3-mimi05633@gmail.com>
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On 09/08/2023 11:51, Mia Lin wrote:
> -	flags = NCT3018Y_BIT_TWO;
> -	err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
> -	if (err < 0) {
> -		dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n");
> -		return err;
> +	flags = i2c_smbus_read_byte_data(client, NCT3018Y_REG_PART);
> +	if (flags < 0) {
> +		dev_dbg(&client->dev, "%s: read error\n", __func__);
> +		return flags;
> +	} else if (flags & NCT3018Y_REG_PART_NCT3018Y) {
> +		if (!(flags & data->part_number))
> +			dev_warn(&client->dev, "%s: part_num=0x%x but NCT3018Y_REG_PART=0x%x\n",
> +				 __func__, data->part_number, flags);
> +		flags = NCT3018Y_BIT_HF;
> +		err = i2c_smbus_write_byte_data(client, NCT3018Y_REG_CTRL, flags);
> +		if (err < 0) {
> +			dev_dbg(&client->dev, "Unable to write NCT3018Y_REG_CTRL\n");
> +			return err;
> +		}
> +	} else if (flags & NCT3018Y_REG_PART_NCT3015Y) {
> +		if (!(flags & data->part_number))
> +			dev_warn(&client->dev, "%s: part_num=0x%x but NCT3018Y_REG_PART=0x%x\n",
> +				 __func__, data->part_number, flags);

I don't think this is correct. Kernel's job is not to verify the DT...
and why would it verify the device based on DT? You have here device
detection so use it directly without this dance of comparing with
compatible/match data.

Best regards,
Krzysztof