Subject: Re: [PATCH] drm/bridge/synopsis: stop clobbering drvdata
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Philippe CORNU <philippe.cornu@st.com>
Cc: Brian Norris <briannorris@chromium.org>,
        Archit Taneja <architt@codeaurora.org>,
        David Airlie <airlied@linux.ie>,
        Yannick FERTRE <yannick.fertre@st.com>,
        Benjamin Gaignard <benjamin.gaignard@linaro.org>,
        Vincent ABRIOU <vincent.abriou@st.com>,
        "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Sean Paul <seanpaul@chromium.org>,
        Nickey Yang <nickey.yang@rock-chips.com>,
        "hl@rock-chips.com" <hl@rock-chips.com>,
        "linux-rockchip@lists.infradead.org" 
        <linux-rockchip@lists.infradead.org>,
        "mka@chromium.org" <mka@chromium.org>
From: Andrzej Hajda <a.hajda@samsung.com>
Message-id: <1446c2ab-cedb-cd8a-adfc-79bcef99c134@samsung.com>
Date: Tue, 09 Jan 2018 14:45:26 +0100
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On 09.01.2018 14:37, Laurent Pinchart wrote:
> Hi Philippe,
>
> On Tuesday, 9 January 2018 15:01:02 EET Philippe CORNU wrote:
>> Hi Archit, Andrzej & Laurent,
>>
>> Regarding this patch from Brian, I think it could be nice to merge it 
>> (1xAcked-by, 2xReviewed-by).
>>
>> Could you please have a look?
>>
>> Only the small "typo" in the headline needs to be changed.
>>
>> Many thanks,
> I've just replied to Brian in this mail thread. Sorry for the delay, it 
> slipped through the cracks. Thank you for pinging me.

I have just pushed the patch to drm-misc-next. I am sorry, if you wanted
to polish it more, from the thread it looked it can be merged as is.

Regards
Andrzej


>> On 11/28/2017 10:34 AM, Philippe CORNU wrote:
>>
>>> Hi Brian,
>>>
>>> On 11/28/2017 02:05 AM, Brian Norris wrote:
>>>
>>>> Bridge drivers/helpers shouldn't be clobbering the drvdata, since a
>>>> parent driver might need to own this. Instead, let's return our
>>>> 'dw_mipi_dsi' object and have callers pass that back to us for removal.
>>>
>>> And many thanks for this cleanup.
>>> (please update the headline with "synopsys")
>>>
>>> Successfully tested on stm.
>>>
>>> Acked-by: Philippe Cornu <philippe.cornu@st.com>
>>>
>>> Many thanks,
>>> Philippe :-)
>>>
>>>>
>>>> Signed-off-by: Brian Norris <briannorris@chromium.org>
>>>> ---
>>>>   drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 36 
>>>> ++++++++++-----------------
>>>>   drivers/gpu/drm/stm/dw_mipi_dsi-stm.c         | 14 +++++++----
>>>>   include/drm/bridge/dw_mipi_dsi.h              | 17 ++++++++-----
>>>>   3 files changed, 33 insertions(+), 34 deletions(-)
>>>>
>>>>
>>>>
>>>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c 
>>>> b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>>> index d9cca4fd66ec..c39c7dce20ed 100644
>>>> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>>> @@ -922,8 +922,6 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>>>>       dsi->bridge.of_node = pdev->dev.of_node;
>>>>   #endif
>>>> -    dev_set_drvdata(dev, dsi);
>>>> -
>>>>       return dsi;
>>>>   }
>>>> @@ -935,23 +933,16 @@ static void __dw_mipi_dsi_remove(struct 
>>>> dw_mipi_dsi *dsi)
>>>>   /*
>>>>    * Probe/remove API, used from platforms based on the DRM bridge API.
>>>>    */
>>>> -int dw_mipi_dsi_probe(struct platform_device *pdev,
>>>> -              const struct dw_mipi_dsi_plat_data *plat_data)
>>>> +struct dw_mipi_dsi *
>>>> +dw_mipi_dsi_probe(struct platform_device *pdev,
>>>> +          const struct dw_mipi_dsi_plat_data *plat_data)
>>>>   {
>>>> -    struct dw_mipi_dsi *dsi;
>>>> -
>>>> -    dsi = __dw_mipi_dsi_probe(pdev, plat_data);
>>>> -    if (IS_ERR(dsi))
>>>> -        return PTR_ERR(dsi);
>>>> -
>>>> -    return 0;
>>>> +    return __dw_mipi_dsi_probe(pdev, plat_data);
>>>>   }
>>>>   EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
>>>> -void dw_mipi_dsi_remove(struct platform_device *pdev)
>>>> +void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
>>>>   {
>>>> -    struct dw_mipi_dsi *dsi = platform_get_drvdata(pdev);
>>>> -
>>>>       mipi_dsi_host_unregister(&dsi->dsi_host);
>>>>       __dw_mipi_dsi_remove(dsi);
>>>> @@ -961,31 +952,30 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_remove);
>>>>   /*
>>>>    * Bind/unbind API, used from platforms based on the component 
>>>> framework.
>>>>    */
>>>> -int dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder 
>>>> *encoder,
>>>> -             const struct dw_mipi_dsi_plat_data *plat_data)
>>>> +struct dw_mipi_dsi *
>>>> +dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder 
>>>> *encoder,
>>>> +         const struct dw_mipi_dsi_plat_data *plat_data)
>>>>   {
>>>>       struct dw_mipi_dsi *dsi;
>>>>       int ret;
>>>>       dsi = __dw_mipi_dsi_probe(pdev, plat_data);
>>>>       if (IS_ERR(dsi))
>>>> -        return PTR_ERR(dsi);
>>>> +        return dsi;
>>>>       ret = drm_bridge_attach(encoder, &dsi->bridge, NULL);
>>>>       if (ret) {
>>>> -        dw_mipi_dsi_remove(pdev);
>>>> +        dw_mipi_dsi_remove(dsi);
>>>>           DRM_ERROR("Failed to initialize bridge with drm\n");
>>>> -        return ret;
>>>> +        return ERR_PTR(ret);
>>>>       }
>>>> -    return 0;
>>>> +    return dsi;
>>>>   }
>>>>   EXPORT_SYMBOL_GPL(dw_mipi_dsi_bind);
>>>> -void dw_mipi_dsi_unbind(struct device *dev)
>>>> +void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi)
>>>>   {
>>>> -    struct dw_mipi_dsi *dsi = dev_get_drvdata(dev);
>>>> -
>>>>       __dw_mipi_dsi_remove(dsi);
>>>>   }
>>>>   EXPORT_SYMBOL_GPL(dw_mipi_dsi_unbind);
>>>> diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c 
>>>> b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>>> index e5b6310240fe..7ed0ef7f6ec2 100644
>>>> --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>>> +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>>> @@ -66,6 +66,7 @@ enum dsi_color {
>>>>   struct dw_mipi_dsi_stm {
>>>>       void __iomem *base;
>>>>       struct clk *pllref_clk;
>>>> +    struct dw_mipi_dsi *dsi;
>>>>   };
>>>>   static inline void dsi_write(struct dw_mipi_dsi_stm *dsi, u32 reg, 
>>>> u32 val)
>>>> @@ -318,21 +319,24 @@ static int dw_mipi_dsi_stm_probe(struct 
>>>> platform_device *pdev)
>>>>       dw_mipi_dsi_stm_plat_data.base = dsi->base;
>>>>       dw_mipi_dsi_stm_plat_data.priv_data = dsi;
>>>> -    ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
>>>> -    if (ret) {
>>>> +    platform_set_drvdata(pdev, dsi);
>>>> +
>>>> +    dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
>>>> +    if (IS_ERR(dsi->dsi)) {
>>>>           DRM_ERROR("Failed to initialize mipi dsi host\n");
>>>>           clk_disable_unprepare(dsi->pllref_clk);
>>>> +        return PTR_ERR(dsi->dsi);
>>>>       }
>>>> -    return ret;
>>>> +    return 0;
>>>>   }
>>>>   static int dw_mipi_dsi_stm_remove(struct platform_device *pdev)
>>>>   {
>>>> -    struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
>>>> +    struct dw_mipi_dsi_stm *dsi = platform_get_drvdata(pdev);
>>>>       clk_disable_unprepare(dsi->pllref_clk);
>>>> -    dw_mipi_dsi_remove(pdev);
>>>> +    dw_mipi_dsi_remove(dsi->dsi);
>>>>       return 0;
>>>>   }
>>>> diff --git a/include/drm/bridge/dw_mipi_dsi.h 
>>>> b/include/drm/bridge/dw_mipi_dsi.h
>>>> index 9b30fec302c8..d9c6d549f971 100644
>>>> --- a/include/drm/bridge/dw_mipi_dsi.h
>>>> +++ b/include/drm/bridge/dw_mipi_dsi.h
>>>> @@ -10,6 +10,8 @@
>>>>   #ifndef __DW_MIPI_DSI__
>>>>   #define __DW_MIPI_DSI__
>>>> +struct dw_mipi_dsi;
>>>> +
>>>>   struct dw_mipi_dsi_phy_ops {
>>>>       int (*init)(void *priv_data);
>>>>       int (*get_lane_mbps)(void *priv_data, struct drm_display_mode 
>>>> *mode,
>>>> @@ -29,11 +31,14 @@ struct dw_mipi_dsi_plat_data {
>>>>       void *priv_data;
>>>>   };
>>>> -int dw_mipi_dsi_probe(struct platform_device *pdev,
>>>> -              const struct dw_mipi_dsi_plat_data *plat_data);
>>>> -void dw_mipi_dsi_remove(struct platform_device *pdev);
>>>> -int dw_mipi_dsi_bind(struct platform_device *pdev, struct drm_encoder 
>>>> *encoder,
>>>> -             const struct dw_mipi_dsi_plat_data *plat_data);
>>>> -void dw_mipi_dsi_unbind(struct device *dev);
>>>> +struct dw_mipi_dsi *dw_mipi_dsi_probe(struct platform_device *pdev,
>>>> +                      const struct dw_mipi_dsi_plat_data
>>>> +                      *plat_data);
>>>> +void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi);
>>>> +struct dw_mipi_dsi *dw_mipi_dsi_bind(struct platform_device *pdev,
>>>> +                     struct drm_encoder *encoder,
>>>> +                     const struct dw_mipi_dsi_plat_data
>>>> +                     *plat_data);
>>>> +void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi);
>>>>   #endif /* __DW_MIPI_DSI__ */
>