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Message-ID: <6035a0d2-f784-c55d-acd5-aa3ffc470246@quicinc.com>
Date: Wed, 21 Feb 2024 16:08:30 +0530
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Subject: Re: [PATCH 2/5] drivers: mtd: nand: Add qpic_common API file
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To: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
CC: <andersson@kernel.org>, <konrad.dybcio@linaro.org>, <broonie@kernel.org>,
        <robh@kernel.org>, <krzysztof.kozlowski+dt@linaro.org>,
        <conor+dt@kernel.org>, <miquel.raynal@bootlin.com>, <richard@nod.at>,
        <vigneshr@ti.com>, <manivannan.sadhasivam@linaro.org>,
        <linux-arm-msm@vger.kernel.org>, <linux-spi@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-mtd@lists.infradead.org>, <quic_srichara@quicinc.com>,
        <quic_varada@quicinc.com>
References: <20240215134856.1313239-1-quic_mdalam@quicinc.com>
 <20240215134856.1313239-3-quic_mdalam@quicinc.com>
 <CAA8EJpquDwDg+OrZKeJrTWEtokCF7uyHMyzCFK2etSsDip8_6Q@mail.gmail.com>
 <c574c9ab-0a47-2dc8-9ddd-c08f1b770d7e@quicinc.com>
 <CAA8EJprkwv0QstJTveM+06DbMjgBCEVBRhBb5i2QM6LxmmCQug@mail.gmail.com>
From: Md Sadre Alam <quic_mdalam@quicinc.com>
In-Reply-To: <CAA8EJprkwv0QstJTveM+06DbMjgBCEVBRhBb5i2QM6LxmmCQug@mail.gmail.com>
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On 2/20/2024 9:37 PM, Dmitry Baryshkov wrote:
> On Tue, 20 Feb 2024 at 17:59, Md Sadre Alam <quic_mdalam@quicinc.com> wrote:
>>
>>
>>
>> On 2/15/2024 8:30 PM, Dmitry Baryshkov wrote:
>>> On Thu, 15 Feb 2024 at 15:53, Md Sadre Alam <quic_mdalam@quicinc.com> wrote:
>>>>
>>>> Add qpic_common.c file which hold all the common
>>>> qpic APIs which will be used by both qpic raw nand
>>>> driver and qpic spi nand driver.
>>>>
>>>> Co-developed-by: Sricharan Ramabadhran <quic_srichara@quicinc.com>
>>>> Signed-off-by: Sricharan Ramabadhran <quic_srichara@quicinc.com>
>>>> Co-developed-by: Varadarajan Narayanan <quic_varada@quicinc.com>
>>>> Signed-off-by: Varadarajan Narayanan <quic_varada@quicinc.com>
>>>> Signed-off-by: Md Sadre Alam <quic_mdalam@quicinc.com>
>>>> ---
>>>>    drivers/mtd/nand/Makefile            |    1 +
>>>>    drivers/mtd/nand/qpic_common.c       |  786 +++++++++++++++++
>>>>    drivers/mtd/nand/raw/qcom_nandc.c    | 1226 +-------------------------
>>>>    include/linux/mtd/nand-qpic-common.h |  488 ++++++++++
>>>>    4 files changed, 1291 insertions(+), 1210 deletions(-)
>>>>    create mode 100644 drivers/mtd/nand/qpic_common.c
>>>>    create mode 100644 include/linux/mtd/nand-qpic-common.h
>>>>
>>>> diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
>>>> index 19e1291ac4d5..131707a41293 100644
>>>> --- a/drivers/mtd/nand/Makefile
>>>> +++ b/drivers/mtd/nand/Makefile
>>>> @@ -12,3 +12,4 @@ nandcore-$(CONFIG_MTD_NAND_ECC) += ecc.o
>>>>    nandcore-$(CONFIG_MTD_NAND_ECC_SW_HAMMING) += ecc-sw-hamming.o
>>>>    nandcore-$(CONFIG_MTD_NAND_ECC_SW_BCH) += ecc-sw-bch.o
>>>>    nandcore-$(CONFIG_MTD_NAND_ECC_MXIC) += ecc-mxic.o
>>>> +obj-y += qpic_common.o
>>>> diff --git a/drivers/mtd/nand/qpic_common.c b/drivers/mtd/nand/qpic_common.c
>>>> new file mode 100644
>>>> index 000000000000..4d74ba888028
>>>> --- /dev/null
>>>> +++ b/drivers/mtd/nand/qpic_common.c
>>>> @@ -0,0 +1,786 @@
>>>> +// SPDX-License-Identifier: GPL-2.0
>>>> +/*
>>>> + * QPIC Controller common API file.
>>>> + * Copyright (C) 2023  Qualcomm Inc.
>>>> + * Authors:    Md sadre Alam           <quic_mdalam@quicinc.com>
>>>> + *             Sricharan R             <quic_srichara@quicinc.com>
>>>> + *             Varadarajan Narayanan   <quic_varada@quicinc.com>
>>>
>>> This is a bit of an exaggeration. You are moving code, not writing new
>>> code. Please retain the existing copyrights for the moved code.
>> Ok
>>>
>>>> + *
>>>> + */
>>>> +
>>>> +#include <linux/mtd/nand-qpic-common.h>
>>>> +
>>>> +struct qcom_nand_controller *
>>>> +get_qcom_nand_controller(struct nand_chip *chip)
>>>> +{
>>>> +       return container_of(chip->controller, struct qcom_nand_controller,
>>>> +                           controller);
>>>> +}
>>>> +EXPORT_SYMBOL(get_qcom_nand_controller);
>>>
>>> NAK for adding functions to the global export namespace without a
>>> proper driver-specific prefix.
>> Ok, will fix in next patch
>>>
>>> Also, a bunch of the code here seems not so well thought. It was fine
>>> for an internal interface, but it doesn't look so good as a common
>>> wrapper. Please consider defining a sensible common code module
>>> interface instead.
>>
>>    QPIC controller will support both raw NAND as well Serial nand interface.
>>    This common API file was the part of raw NAND driver , since for serial
>>    nand most of the APIs from raw nand driver will be re-used that's why i
>>    have created this common API file, so that QPIC serial nand driver
>>    drivers/spi/spi-qpic-snand.c and QPIC raw NAND driver
>>    drivers/mtd/nand/raw/qcom_nandc.c can used these common APIs.
>>
>>    Could you please suggest how I should handle this in batter way.
> 
> Yes. Start by designing common accessor functions that form a
> sufficient and complete API to access the hardware functionality. A
> set of functions blindly moved from the existing driver usually do not
> make such an API, because usually nobody cares enough about the driver
> internals. It should be something that external user (NAND, SPI, etc)
> can use without looking into the actual implementation of these
> functions.
  Thanks for suggestion. Will make the Common API more generic and
  post in next patch.
>