Linux-i2c Archive on lore.kernel.org
 help / color / Atom feed
From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Christian Eggers <ceggers@arri.de>
Cc: Oleksij Rempel <linux@rempel-privat.de>,
	Shawn Guo <shawnguo@kernel.org>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Fabio Estevam <festevam@gmail.com>,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	NXP Linux Team <linux-imx@nxp.com>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org
Subject: Re: [PATCH v2 1/3] i2c: imx: Fix reset of I2SR_IAL flag
Date: Tue, 6 Oct 2020 08:05:28 +0200
Message-ID: <20201006060528.drh2yoo2dklyntez@pengutronix.de> (raw)
In-Reply-To: <20201002152305.4963-2-ceggers@arri.de>


[-- Attachment #1: Type: text/plain, Size: 1771 bytes --]

On Fri, Oct 02, 2020 at 05:23:03PM +0200, Christian Eggers wrote:
> According to the "VFxxx Controller Reference Manual" (and the comment
> block starting at line 97), Vybrid requires writing a one for clearing
> an interrupt flag. Syncing the method for clearing I2SR_IIF in
> i2c_imx_isr().
> 
> Signed-off-by: Christian Eggers <ceggers@arri.de>
> Cc: stable@vger.kernel.org
> ---
>  drivers/i2c/busses/i2c-imx.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index 0ab5381aa012..34648df7f1a6 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -424,7 +424,12 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool a
>  
>  		/* check for arbitration lost */
>  		if (temp & I2SR_IAL) {
> -			temp &= ~I2SR_IAL;
> +			/*
> +			 * i2sr_clr_opcode is the value to clear all interrupts.
> +			 * Here we want to clear only I2SR_IAL, so we write
> +			 * ~i2sr_clr_opcode with just the I2SR_IAL bit toggled.
> +			 */
> +			temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ I2SR_IAL;
>  			imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
>  			return -EAGAIN;

Could we please move clearing an irq to a dedicated function? Such that
it looks like:

	/* check for arbitration lost */
	if (temp & I2SR_IAL) {
		i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
		return -EAGAIN;
	}

Then you also don't need to duplicate the describing comment but just
add it to the implementation of i2c_imx_clear_irq().

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]

  parent reply index

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-02 15:23 [PATCH v2 0/3] i2c: imx: Fix handling of arbitration loss Christian Eggers
2020-10-02 15:23 ` [PATCH v2 1/3] i2c: imx: Fix reset of I2SR_IAL flag Christian Eggers
2020-10-05  8:05   ` Krzysztof Kozlowski
2020-10-06  6:05   ` Uwe Kleine-König [this message]
2020-10-06 10:51     ` [PATCH v3 0/3] i2c: imx: Fix handling of arbitration loss Christian Eggers
2020-10-06 10:51       ` [PATCH v3 1/3] i2c: imx: Fix reset of I2SR_IAL flag Christian Eggers
2020-10-06 12:06         ` David Laight
2020-10-06 12:30           ` Christian Eggers
2020-10-06 12:46           ` Uwe Kleine-König
2020-10-06 12:52             ` David Laight
2020-10-06 10:51       ` [PATCH v3 2/3] i2c: imx: Check for I2SR_IAL after every byte Christian Eggers
2020-10-06 10:51       ` [PATCH v3 3/3] i2c: imx: Don't generate STOP condition if arbitration has been lost Christian Eggers
2020-10-02 15:23 ` [PATCH v2 2/3] i2c: imx: Check for I2SR_IAL after every byte Christian Eggers
2020-10-05  8:07   ` Krzysztof Kozlowski
2020-10-05  9:25     ` Christian Eggers
2020-10-02 15:23 ` [PATCH v2 3/3] i2c: imx: Don't generate STOP condition if arbitration has been lost Christian Eggers
2020-10-05  8:16   ` Krzysztof Kozlowski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201006060528.drh2yoo2dklyntez@pengutronix.de \
    --to=u.kleine-koenig@pengutronix.de \
    --cc=ceggers@arri.de \
    --cc=festevam@gmail.com \
    --cc=kernel@pengutronix.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-imx@nxp.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@rempel-privat.de \
    --cc=s.hauer@pengutronix.de \
    --cc=shawnguo@kernel.org \
    --cc=stable@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-i2c Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-i2c/0 linux-i2c/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-i2c linux-i2c/ https://lore.kernel.org/linux-i2c \
		linux-i2c@vger.kernel.org
	public-inbox-index linux-i2c

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-i2c


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git