linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Mark Brown <broonie@kernel.org>
To: Jon Lin <jon.lin@rock-chips.com>
Cc: heiko@sntech.de, linux-spi@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v10 5/6] spi: rockchip: Support cs-gpio
Date: Fri, 11 Feb 2022 11:48:26 +0000	[thread overview]
Message-ID: <YgZNCoYeArYTECYC@sirena.org.uk> (raw)
In-Reply-To: <20220211034344.4130-5-jon.lin@rock-chips.com>

[-- Attachment #1: Type: text/plain, Size: 1162 bytes --]

On Fri, Feb 11, 2022 at 11:43:41AM +0800, Jon Lin wrote:
> 1.Add standard cs-gpio support
> 2.Refer to spi-controller.yaml for details
> 
> Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
> ---
> 
> Changes in v10: None
> Changes in v9: None
> Changes in v8: None
> Changes in v7: None
> Changes in v6: None
> Changes in v5: None
> Changes in v4: None
> Changes in v3: None

Why is this the one patch in the series with any versioning information?

> -		ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER,
> -				      BIT(spi->chip_select));
> +		if (spi->cs_gpiod)
> +			ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER, 1);
> +		else
> +			ROCKCHIP_SPI_SET_BITS(rs->regs + ROCKCHIP_SPI_SER, BIT(spi->chip_select));

This appears to be making the device control chip select 0 if a GPIO
chip select is used - that's going to work poorly if there's a device
using that chip select.  It should be fine to prohibit that
configuration if the hardware requires that a GPIO be controlled,
especially if the native chip select can be pinmuxed to a GPIO, but it
ought to be at least documented that this won't work and ideally
detected.

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

  reply	other threads:[~2022-02-11 11:48 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-02-11  3:43 [PATCH 1/6] spi: rockchip: Stop spi slave dma receiver when cs inactive Jon Lin
2022-02-11  3:43 ` [PATCH 2/6] spi: rockchip: Preset cs-high and clk polarity in setup progress Jon Lin
2022-02-11 11:24   ` Mark Brown
     [not found]     ` <4222ce7d-a1e3-1728-fec2-976946b06ba9@rock-chips.com>
2022-02-14 12:49       ` Mark Brown
     [not found]         ` <e0f0ca0d-40df-cf86-9471-9272bcc171f9@rock-chips.com>
2022-02-15 12:36           ` Mark Brown
2022-02-16  1:23             ` Jon Lin
2022-02-11  3:43 ` [PATCH 3/6] spi: rockchip: Fix error in getting num-cs property Jon Lin
2022-02-11 11:25   ` Mark Brown
2022-02-11  3:43 ` [PATCH 4/6] spi: rockchip: Suspend and resume the bus during NOIRQ_SYSTEM_SLEEP_PM ops Jon Lin
2022-02-11  3:43 ` [PATCH v10 5/6] spi: rockchip: Support cs-gpio Jon Lin
2022-02-11 11:48   ` Mark Brown [this message]
2022-02-11  3:43 ` [PATCH 5/6] spi: rockchip: terminate dma transmission when slave abort Jon Lin
2022-02-11 11:49   ` Mark Brown
2022-02-11  3:43 ` [PATCH 6/6] spi: rockchip: clear interrupt status in error handler Jon Lin
2022-02-11  3:43 ` [PATCH v10 6/6] spi: rockchip: Support SPI_CS_HIGH Jon Lin
  -- strict thread matches above, loose matches on Subject: below --
2021-06-21 10:47 [PATCH v10 0/6] Support ROCKCHIP SPI new feature Jon Lin
2021-06-21 10:48 ` [PATCH v10 5/6] spi: rockchip: Support cs-gpio Jon Lin

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=YgZNCoYeArYTECYC@sirena.org.uk \
    --to=broonie@kernel.org \
    --cc=heiko@sntech.de \
    --cc=jon.lin@rock-chips.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rockchip@lists.infradead.org \
    --cc=linux-spi@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
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).