Subject: Re: [v5,6/6] usb: dwc3: Do not set dma coherent mask
To: Sriram Dash <sriram.dash@nxp.com>, <linux-kernel@vger.kernel.org>,
        <linux-usb@vger.kernel.org>
References: <1479383028-27701-7-git-send-email-sriram.dash@nxp.com>
CC: <mathias.nyman@intel.com>, <gregkh@linuxfoundation.org>,
        <suresh.gupta@nxp.com>, <felipe.balbi@linux.intel.com>,
        <stern@rowland.harvard.edu>, <pku.leo@gmail.com>,
        Arnd Bergmann <arnd@arndb.de>
From: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Message-ID: <0ff80ab2-922f-da05-03fd-22f43f7604d7@nokia.com>
Date: Tue, 13 Dec 2016 17:09:52 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101
 Thunderbird/45.5.0
MIME-Version: 1.0
In-Reply-To: <1479383028-27701-7-git-send-email-sriram.dash@nxp.com>
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 7bit
SpamDiagnosticOutput: 1:99
SpamDiagnosticMetadata: NSPM
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Dec 2016 16:09:57.8150 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-Transport-CrossTenantHeadersStamped: HE1PR07MB1321
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 2180
Lines: 78

Hi!

On 17/11/16 12:43, Sriram Dash wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> The dma mask is correctly set up by the DT probe function, no
> need to override it any more.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Sriram Dash <sriram.dash@nxp.com>

Successfully tested on arm64/axxia with DWC3 USB host, XHCIs properly inherit
DMA configuration. Therefore:

Tested-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>

> ---
> Changes in v5:
>   - No update
> 
> Changes in v4:
>   - No update
> 
> Changes in v3:
>   - No update
> 
> Changes in v2:
>   - club the cleanup for dma coherent mask for device
> 
>  drivers/usb/dwc3/dwc3-exynos.c | 10 ----------
>  drivers/usb/dwc3/dwc3-st.c     |  1 -
>  2 files changed, 11 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-exynos.c b/drivers/usb/dwc3/dwc3-exynos.c
> index 2f1fb7e..e27899b 100644
> --- a/drivers/usb/dwc3/dwc3-exynos.c
> +++ b/drivers/usb/dwc3/dwc3-exynos.c
> @@ -20,7 +20,6 @@
>  #include <linux/kernel.h>
>  #include <linux/slab.h>
>  #include <linux/platform_device.h>
> -#include <linux/dma-mapping.h>
>  #include <linux/clk.h>
>  #include <linux/usb/otg.h>
>  #include <linux/usb/usb_phy_generic.h>
> @@ -117,15 +116,6 @@ static int dwc3_exynos_probe(struct platform_device *pdev)
>  	if (!exynos)
>  		return -ENOMEM;
>  
> -	/*
> -	 * Right now device-tree probed devices don't get dma_mask set.
> -	 * Since shared usb code relies on it, set it here for now.
> -	 * Once we move to full device tree support this will vanish off.
> -	 */
> -	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
> -	if (ret)
> -		return ret;
> -
>  	platform_set_drvdata(pdev, exynos);
>  
>  	exynos->dev	= dev;
> diff --git a/drivers/usb/dwc3/dwc3-st.c b/drivers/usb/dwc3/dwc3-st.c
> index 89a2f71..4d7439c 100644
> --- a/drivers/usb/dwc3/dwc3-st.c
> +++ b/drivers/usb/dwc3/dwc3-st.c
> @@ -218,7 +218,6 @@ static int st_dwc3_probe(struct platform_device *pdev)
>  	if (IS_ERR(regmap))
>  		return PTR_ERR(regmap);
>  
> -	dma_set_coherent_mask(dev, dev->coherent_dma_mask);
>  	dwc3_data->dev = dev;
>  	dwc3_data->regmap = regmap;
>  
> 

-- 
Best regards,
Alexander Sverdlin.