linux-kernel - Re: [PATCH v3 05/24] drm/rockchip: dw-mipi-dsi: fix generic packet status check

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Message-ID: <20170130175604.GF20076@art_vandelay>
Date:   Mon, 30 Jan 2017 12:56:04 -0500
From:   Sean Paul <seanpaul@...omium.org>
To:     John Keeping <john@...anate.com>
Cc:     Mark Yao <mark.yao@...k-chips.com>, linux-kernel@...r.kernel.org,
        dri-devel@...ts.freedesktop.org,
        linux-rockchip@...ts.infradead.org,
        Chris Zhong <zyw@...k-chips.com>,
        linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH v3 05/24] drm/rockchip: dw-mipi-dsi: fix generic packet
 status check

On Sun, Jan 29, 2017 at 01:24:25PM +0000, John Keeping wrote:
> We want to check that both the GEN_CMD_EMPTY and GEN_PLD_W_EMPTY bits
> are set so we can't just check "val & mask" because that will be true if
> either bit is set.
> 

Reviewed-by: Sean Paul <seanpaul@...omium.org>

> Signed-off-by: John Keeping <john@...anate.com>
> Reviewed-by: Chris Zhong <zyw@...k-chips.com>
> ---
> v3:
> - Add Chris' Reviewed-by
> Unchanged in v2
> 
>  drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> index 4cbbbcb619b7..4be1ff3a42bb 100644
> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> @@ -545,7 +545,7 @@ static int dw_mipi_dsi_host_detach(struct mipi_dsi_host *host,
>  static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>  {
>  	int ret;
> -	u32 val;
> +	u32 val, mask;
>  
>  	ret = readx_poll_timeout(readl, dsi->base + DSI_CMD_PKT_STATUS,
>  				 val, !(val & GEN_CMD_FULL), 1000,
> @@ -557,8 +557,9 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>  
>  	dsi_write(dsi, DSI_GEN_HDR, hdr_val);
>  
> +	mask = GEN_CMD_EMPTY | GEN_PLD_W_EMPTY;
>  	ret = readx_poll_timeout(readl, dsi->base + DSI_CMD_PKT_STATUS,
> -				 val, val & (GEN_CMD_EMPTY | GEN_PLD_W_EMPTY),
> +				 val, (val & mask) == mask,
>  				 1000, CMD_PKT_STATUS_TIMEOUT_US);
>  	if (ret < 0) {
>  		dev_err(dsi->dev, "failed to write command FIFO\n");
> -- 
> 2.11.0.197.gb556de5.dirty
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Sean Paul, Software Engineer, Google / Chromium OS

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