linux-spi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sean Anderson <seanga2@gmail.com>
To: Damien Le Moal <damien.lemoal@wdc.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	linux-riscv@lists.infradead.org, Rob Herring <robh+dt@kernel.org>,
	Frank Rowand <frowand.list@gmail.com>,
	devicetree@vger.kernel.org, Serge Semin <fancer.lancer@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	linux-spi@vger.kernel.org, Stephen Boyd <sboyd@kernel.org>,
	linux-clk@vger.kernel.org,
	Linus Walleij <linus.walleij@linaro.org>,
	linux-gpio@vger.kernel.org,
	Philipp Zabel <p.zabel@pengutronix.de>
Subject: Re: [PATCH 03/32] spi: dw: Fix driving MOSI low while recieving
Date: Sat, 7 Nov 2020 08:30:21 -0500	[thread overview]
Message-ID: <2f2acc07-aa00-5d21-e8f6-d99407bf9590@gmail.com> (raw)
In-Reply-To: <20201107081420.60325-4-damien.lemoal@wdc.com>

On 11/7/20 3:13 AM, Damien Le Moal wrote:
> Fix for the Synopsis DesignWare SPI mmio driver taken from the work
> by Sean Anderson for the U-Boot project. Sean comments:
> 
> The resting state of MOSI is high when nothing is driving it. If we
> drive it low while recieving, it looks like we are transmitting 0x00
> instead of transmitting nothing. This can confuse slaves (like SD cards)
> which allow new commands to be sent over MOSI while they are returning
> data over MISO. The return of MOSI from 0 to 1 at the end of recieving
> a byte can look like a start bit and a transmission bit to an SD card.
> This will cause the card to become out-of-sync with the SPI device, as
> it thinks the device has already started transmitting two bytes of a new
> command. The mmc-spi driver will not detect the R1 response from the SD
> card, since it is sent too early, and offset by two bits. This patch
> fixes transfer errors when using SD cards with dw spi.
> 
> Signed-off-by: Sean Anderson <seanga2@gmail.com>
> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
> ---
>  drivers/spi/spi-dw-core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c
> index 841c85247f01..c2ef1d8d46d5 100644
> --- a/drivers/spi/spi-dw-core.c
> +++ b/drivers/spi/spi-dw-core.c
> @@ -137,7 +137,7 @@ static inline u32 rx_max(struct dw_spi *dws)
>  static void dw_writer(struct dw_spi *dws)
>  {
>  	u32 max = tx_max(dws);
> -	u16 txw = 0;
> +	u16 txw = 0xffff;
>  
>  	while (max--) {
>  		if (dws->tx) {
> 

Reviewed-by: Sean Anderson <seanga2@gmail.com>

  reply	other threads:[~2020-11-07 13:30 UTC|newest]

Thread overview: 132+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-07  8:13 [PATCH 00/32] RISC-V Kendryte K210 support improvments Damien Le Moal
2020-11-07  8:13 ` [PATCH 01/32] of: Fix property supplier parsing Damien Le Moal
2020-11-09 15:05   ` Serge Semin
2020-11-09 15:14   ` Andy Shevchenko
2020-11-09 17:44     ` Serge Semin
2020-11-09 20:52       ` Rob Herring
2020-11-07  8:13 ` [PATCH 02/32] spi: dw: Add support for 32-bits ctrlr0 layout Damien Le Moal
2020-11-07 13:28   ` Sean Anderson
2020-11-09 14:25   ` Serge Semin
2020-11-09 14:33     ` Sean Anderson
2020-11-09 14:35       ` Sean Anderson
2020-11-09 14:40       ` Andy Shevchenko
2020-11-09 14:41         ` Andy Shevchenko
2020-11-09 14:49           ` Sean Anderson
2020-11-09 15:10             ` Andy Shevchenko
2020-11-09 14:36     ` Andy Shevchenko
2020-11-09 17:56       ` Serge Semin
2020-11-07  8:13 ` [PATCH 03/32] spi: dw: Fix driving MOSI low while recieving Damien Le Moal
2020-11-07 13:30   ` Sean Anderson [this message]
2020-11-09 13:29   ` Mark Brown
2020-11-09 13:47     ` Sean Anderson
2020-11-09 14:14       ` Mark Brown
2020-11-09 14:48         ` Serge Semin
2020-11-09 16:45           ` Mark Brown
2020-11-09 19:19         ` Serge Semin
2020-11-09 19:40           ` Sean Anderson
2020-11-09 20:17             ` Serge Semin
2020-11-09 20:29               ` Mark Brown
2020-11-09 20:20           ` Mark Brown
2020-11-09 21:05             ` Serge Semin
2020-11-10 13:43               ` Mark Brown
2020-11-07  8:13 ` [PATCH 04/32] spi: dw: Introduce polling device tree property Damien Le Moal
2020-11-09 16:04   ` Mark Brown
2020-11-09 19:59   ` Serge Semin
2020-11-13  9:22     ` Damien Le Moal
2020-11-15 16:01       ` Serge Semin
2020-11-16  7:47         ` Damien Le Moal
2020-11-16 12:33           ` Mark Brown
2020-11-16 21:55           ` Serge Semin
2020-11-17 14:44             ` Damien Le Moal
2020-11-17 18:26               ` Serge Semin
2020-11-18  4:41                 ` Damien Le Moal
2020-11-18 15:16                   ` Serge Semin
2020-11-19  5:12                     ` Damien Le Moal
2020-11-19  8:51                       ` Serge Semin
2020-11-19  8:57                         ` Damien Le Moal
2020-11-07  8:13 ` [PATCH 05/32] spi: dw: Introduce DW_SPI_CAP_POLL_NODELAY Damien Le Moal
2020-11-09 14:03   ` Mark Brown
2020-11-09 20:45   ` Serge Semin
2020-11-07  8:13 ` [PATCH 06/32] spi: dw: Add support for the Kendryte K210 SoC Damien Le Moal
2020-11-07 13:31   ` Sean Anderson
2020-11-07 13:42     ` Damien Le Moal
2020-11-07 13:52       ` Sean Anderson
2020-11-09 14:15         ` Mark Brown
2020-11-13  8:00     ` Damien Le Moal
2020-11-09 21:21   ` Serge Semin
2020-11-09 21:39     ` Damien Le Moal
2020-11-09 21:55       ` Rob Herring
2020-11-09 22:00         ` Damien Le Moal
2020-11-09 23:07           ` Rob Herring
2020-11-10  0:35             ` Damien Le Moal
2020-11-07  8:13 ` [PATCH 07/32] dt-bindings: Update DW SPI device tree bindings Damien Le Moal
2020-11-07  8:13 ` [PATCH 08/32] riscv: Fix kernel time_init() Damien Le Moal
2020-11-12  7:21   ` Atish Patra
2020-11-13  7:31   ` Stephen Boyd
2020-11-07  8:13 ` [PATCH 09/32] riscv: Fix SiFive gpio probe Damien Le Moal
2020-11-10 14:39   ` Linus Walleij
2020-11-07  8:13 ` [PATCH 10/32] riscv: Fix sifive serial driver Damien Le Moal
2020-11-07  8:13 ` [PATCH 11/32] riscv: Enable interrupts during syscalls with M-Mode Damien Le Moal
2020-11-07  8:14 ` [PATCH 12/32] riscv: Automatically select sysctl config options Damien Le Moal
2020-11-07  8:14 ` [PATCH 13/32] riscv: Fix builtin DTB handling Damien Le Moal
2020-11-15  4:17   ` kernel test robot
2020-11-07  8:14 ` [PATCH 14/32] dt-bindings: Define all Kendryte K210 clock IDs Damien Le Moal
2020-11-07 13:33   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 15/32] dt-bindings: Define Kendryte K210 sysctl registers Damien Le Moal
2020-11-07 13:34   ` Sean Anderson
2020-11-09 21:59   ` Rob Herring
2020-11-09 22:10     ` Sean Anderson
2020-11-09 23:01       ` Rob Herring
2020-11-07  8:14 ` [PATCH 16/32] dt-bindings: Define Kendryte K210 pin functions Damien Le Moal
2020-11-07 13:38   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 17/32] dt-bindings: Define Kendryte K210 reset signals Damien Le Moal
2020-11-07 13:38   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 18/32] riscv: Add Kendryte K210 SoC clock driver Damien Le Moal
2020-11-07 13:48   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 19/32] riscv: Add Kendryte K210 SoC reset controller Damien Le Moal
2020-11-07 13:58   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 20/32] riscv: Add Kendryte K210 FPIOA pinctrl driver Damien Le Moal
2020-11-09 18:48   ` kernel test robot
2020-11-15  0:28   ` kernel test robot
2020-11-24  8:43   ` Linus Walleij
2020-11-24  8:53     ` Damien Le Moal
2020-11-29 21:33       ` Linus Walleij
2020-11-30  3:13         ` Damien Le Moal
2020-11-30  7:05           ` Serge Semin
2020-11-30  7:27             ` Damien Le Moal
2020-11-24  8:56     ` Damien Le Moal
2020-11-07  8:14 ` [PATCH 21/32] dt-bindings: Add Kendryte and Canaan vendor prefix Damien Le Moal
2020-11-07 14:03   ` Sean Anderson
2020-11-13  8:17     ` Damien Le Moal
2020-11-09 22:01   ` Rob Herring
2020-11-09 22:04     ` Damien Le Moal
2020-11-07  8:14 ` [PATCH 22/32] dt-binding: Document kendryte,k210-sysctl bindings Damien Le Moal
2020-11-07 14:05   ` Sean Anderson
2020-11-09 15:32   ` Rob Herring
2020-11-07  8:14 ` [PATCH 23/32] dt-binding: Document kendryte,k210-clk bindings Damien Le Moal
2020-11-07 14:05   ` Sean Anderson
2020-11-09 21:58   ` Rob Herring
2020-11-07  8:14 ` [PATCH 24/32] dt-bindings: Document kendryte,k210-fpioa bindings Damien Le Moal
2020-11-07 14:06   ` Sean Anderson
2020-11-09 15:32   ` Rob Herring
2020-11-09 15:36   ` Rob Herring
2020-11-09 15:45     ` Sean Anderson
2020-11-11 14:32       ` Rob Herring
2020-11-19 10:57       ` Geert Uytterhoeven
2020-11-19 11:22         ` Damien Le Moal
2020-11-07  8:14 ` [PATCH 25/32] dt-bindings: Document kendryte,k210-rst bindings Damien Le Moal
2020-11-07 14:07   ` Sean Anderson
2020-11-09 15:37   ` Rob Herring
2020-11-09 15:41   ` Rob Herring
2020-11-07  8:14 ` [PATCH 26/32] riscv: Update Kendryte K210 device tree Damien Le Moal
2020-11-07 14:08   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 27/32] riscv: Add SiPeed MAIX BiT board " Damien Le Moal
2020-11-07 14:13   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 28/32] riscv: Add SiPeed MAIX DOCK " Damien Le Moal
2020-11-07  8:14 ` [PATCH 29/32] riscv: Add SiPeed MAIX GO " Damien Le Moal
2020-11-07  8:14 ` [PATCH 30/32] riscv: Add SiPeed MAIXDUINO " Damien Le Moal
2020-11-07 14:14   ` Sean Anderson
2020-11-07  8:14 ` [PATCH 31/32] riscv: Add Kendryte KD233 " Damien Le Moal
2020-11-07  8:14 ` [PATCH 32/32] riscv: Update Kendryte K210 defconfig Damien Le Moal
2020-11-09 12:51 ` [PATCH 00/32] RISC-V Kendryte K210 support improvments Mark Brown
2020-11-09 12:55   ` Damien Le Moal

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=2f2acc07-aa00-5d21-e8f6-d99407bf9590@gmail.com \
    --to=seanga2@gmail.com \
    --cc=broonie@kernel.org \
    --cc=damien.lemoal@wdc.com \
    --cc=devicetree@vger.kernel.org \
    --cc=fancer.lancer@gmail.com \
    --cc=frowand.list@gmail.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-gpio@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=linux-spi@vger.kernel.org \
    --cc=p.zabel@pengutronix.de \
    --cc=palmer@dabbelt.com \
    --cc=robh+dt@kernel.org \
    --cc=sboyd@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).