Re: [PATCH] drm/bridge/synopsis: stop clobbering drvdata

From: Philippe CORNU
Date: Tue Nov 28 2017 - 04:35:02 EST

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@xxxxxx>

Many thanks,
Philippe :-)
>
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
> ---
> 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__ */
>