dw-mipi-dsi based drivers such as dw-mipi-dsi-rockchip or dw_mipi_dsi-stm
depend on dw_mipi_dsi_probe() to initialize the dw_mipi_dsi driver
structure (dmd pointer). This structure is only initialized once
dw_mipi_dsi_probe() returns, creating the link between the locally created
structure and the actual dmd pointer.
Probing the dsi host can be deferred in case of dependency to a dsi
phy-supply (eg. "rockchip,px30-dsi-dphy"). Meanwhile dsi-device drivers
like panels (eg. "ltk050h3146w") can already be registered on the bus.
In that case, when attempting, to register the dsi host from
dw_mipi_dsi_probe() using mipi_dsi_host_register(), the panel probe is
called with a dsi-host pointer that is still locally allocated in
dw_mipi_dsi_probe().
While probing, the panel driver tries to attach to a dsi host
(mipi_dsi_attach()) which calls in return for the specific dsi host
attach hook. (e.g. dw_mipi_dsi_rockchip_host_attach()).
dw_mipi_dsi_rockchip uses the component framework.
In the attach hook, the host component is registered which calls in return
for drm_bridge_attach() while trying to bind the component
(dw_mipi_dsi_bind())
drm_bridge_attach() requires a valid drm bridge parameter. However, the
drm bridge (&dmd->bridge) that will be passed, is not yet initialized since
the dw_mipi_dsi_probe() has not yet returned. This call will fail with a
fatal error (invalid bridge) causing the panel to not be probed again.
To simplify the issue: drm_bridge_attach() depends on the result pointer
of dw_mipi_dsi_probe().
While, if the dsi probe is deferred, drm_bridge_attach() is called before
dw_mipi_dsi_probe() returns.
drm_bridge_attach+0x14/0x1ac
dw_mipi_dsi_bind+0x24/0x30
dw_mipi_dsi_rockchip_bind+0x258/0x378
component_bind_all+0x118/0x248
rockchip_drm_bind+0xb0/0x1f8
try_to_bring_up_aggregate_device+0x168/0x1d4
__component_add+0xa4/0x170
component_add+0x14/0x20
dw_mipi_dsi_rockchip_host_attach+0x54/0x144
dw_mipi_dsi_host_attach+0x9c/0xcc
mipi_dsi_attach+0x28/0x3c
ltk050h3146w_probe+0x10c/0x1a4
mipi_dsi_drv_probe+0x20/0x2c
really_probe+0x148/0x2ac
__driver_probe_device+0x78/0x12c
driver_probe_device+0xdc/0x160
__device_attach_driver+0xb8/0x134
bus_for_each_drv+0x80/0xdc
__device_attach+0xa8/0x1b0
device_initial_probe+0x14/0x20
bus_probe_device+0xa8/0xac
device_add+0x5cc/0x778
mipi_dsi_device_register_full+0xd8/0x198
mipi_dsi_host_register+0x98/0x18c
__dw_mipi_dsi_probe+0x290/0x35c
dw_mipi_dsi_probe+0x10/0x6c
dw_mipi_dsi_rockchip_probe+0x208/0x3e4
platform_probe+0x68/0xdc
really_probe+0x148/0x2ac
__driver_probe_device+0x78/0x12c
driver_probe_device+0xdc/0x160
__device_attach_driver+0xb8/0x134
bus_for_each_drv+0x80/0xdc
__device_attach+0xa8/0x1b0
device_initial_probe+0x14/0x20
bus_probe_device+0xa8/0xac
deferred_probe_work_func+0x88/0xc0
process_one_work+0x138/0x260
worker_thread+0x32c/0x438
kthread+0x118/0x11c
ret_from_fork+0x10/0x20
---[ end trace 0000000000000000 ]---
Fix this by initializing directly the dmd pointer in dw_mipi_dsi_probe(),
which requires also initializting the dmd->bridge attributes that are
required in drm_bridge_attach() before calling mipi_dsi_host_register().
Signed-off-by: Farouk Bouabid <[email protected]>
---
drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c | 4 +-
drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 42 ++++++++++---------
drivers/gpu/drm/meson/meson_dw_mipi_dsi.c | 8 ++--
.../gpu/drm/rockchip/dw-mipi-dsi-rockchip.c | 5 +--
drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 5 +--
include/drm/bridge/dw_mipi_dsi.h | 5 ++-
6 files changed, 35 insertions(+), 34 deletions(-)
diff --git a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
index 3ff30ce80c5b..469976ad3b19 100644
--- a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
@@ -881,8 +881,8 @@ static int imx93_dsi_probe(struct platform_device *pdev)
dsi->pdata.priv_data = dsi;
platform_set_drvdata(pdev, dsi);
- dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
- if (IS_ERR(dsi->dmd))
+ ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
+ if (ret < 0)
return dev_err_probe(dev, PTR_ERR(dsi->dmd),
"failed to probe dw_mipi_dsi\n");
diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index 824fb3c65742..306cba366ba8 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -1184,18 +1184,19 @@ static void dw_mipi_dsi_debugfs_remove(struct dw_mipi_dsi *dsi) { }
#endif /* CONFIG_DEBUG_FS */
-static struct dw_mipi_dsi *
-__dw_mipi_dsi_probe(struct platform_device *pdev,
- const struct dw_mipi_dsi_plat_data *plat_data)
+int __dw_mipi_dsi_probe(struct platform_device *pdev,
+ const struct dw_mipi_dsi_plat_data *plat_data, struct dw_mipi_dsi **dsi_p)
{
struct device *dev = &pdev->dev;
struct reset_control *apb_rst;
struct dw_mipi_dsi *dsi;
int ret;
- dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
- if (!dsi)
- return ERR_PTR(-ENOMEM);
+ *dsi_p = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
+ if (!*dsi_p)
+ return -ENOMEM;
+
+ dsi = *dsi_p;
dsi->dev = dev;
dsi->plat_data = plat_data;
@@ -1203,13 +1204,13 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps ||
!plat_data->phy_ops->get_timing) {
DRM_ERROR("Phy not properly configured\n");
- return ERR_PTR(-ENODEV);
+ return -ENODEV;
}
if (!plat_data->base) {
dsi->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(dsi->base))
- return ERR_PTR(-ENODEV);
+ return -ENODEV;
} else {
dsi->base = plat_data->base;
@@ -1219,7 +1220,7 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
if (IS_ERR(dsi->pclk)) {
ret = PTR_ERR(dsi->pclk);
dev_err(dev, "Unable to get pclk: %d\n", ret);
- return ERR_PTR(ret);
+ return ret;
}
/*
@@ -1233,14 +1234,14 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
if (ret != -EPROBE_DEFER)
dev_err(dev, "Unable to get reset control: %d\n", ret);
- return ERR_PTR(ret);
+ return ret;
}
if (apb_rst) {
ret = clk_prepare_enable(dsi->pclk);
if (ret) {
dev_err(dev, "%s: Failed to enable pclk\n", __func__);
- return ERR_PTR(ret);
+ return ret;
}
reset_control_assert(apb_rst);
@@ -1255,19 +1256,20 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
dsi->dsi_host.dev = dev;
+ dsi->bridge.driver_private = dsi;
+ dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
+ dsi->bridge.of_node = pdev->dev.of_node;
+
ret = mipi_dsi_host_register(&dsi->dsi_host);
if (ret) {
dev_err(dev, "Failed to register MIPI host: %d\n", ret);
pm_runtime_disable(dev);
dw_mipi_dsi_debugfs_remove(dsi);
- return ERR_PTR(ret);
+ return ret;
}
- dsi->bridge.driver_private = dsi;
- dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
- dsi->bridge.of_node = pdev->dev.of_node;
- return dsi;
+ return 0;
}
static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
@@ -1301,11 +1303,11 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_get_bridge);
/*
* Probe/remove API, used from platforms based on the DRM bridge API.
*/
-struct dw_mipi_dsi *
-dw_mipi_dsi_probe(struct platform_device *pdev,
- const struct dw_mipi_dsi_plat_data *plat_data)
+int dw_mipi_dsi_probe(struct platform_device *pdev,
+ const struct dw_mipi_dsi_plat_data *plat_data,
+ struct dw_mipi_dsi **dsi_p)
{
- return __dw_mipi_dsi_probe(pdev, plat_data);
+ return __dw_mipi_dsi_probe(pdev, plat_data, dsi_p);
}
EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
diff --git a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
index e5fe4e994f43..b103f3e31f2a 100644
--- a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
+++ b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
@@ -262,6 +262,7 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
{
struct meson_dw_mipi_dsi *mipi_dsi;
struct device *dev = &pdev->dev;
+ int ret;
mipi_dsi = devm_kzalloc(dev, sizeof(*mipi_dsi), GFP_KERNEL);
if (!mipi_dsi)
@@ -315,10 +316,9 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
mipi_dsi->pdata.priv_data = mipi_dsi;
platform_set_drvdata(pdev, mipi_dsi);
- mipi_dsi->dmd = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata);
- if (IS_ERR(mipi_dsi->dmd))
- return dev_err_probe(dev, PTR_ERR(mipi_dsi->dmd),
- "Failed to probe dw_mipi_dsi\n");
+ ret = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata, &mipi_dsi->dmd);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Failed to probe dw_mipi_dsi\n");
return 0;
}
diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
index 6396f9324dab..4df32747476c 100644
--- a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
@@ -1457,9 +1457,8 @@ static int dw_mipi_dsi_rockchip_probe(struct platform_device *pdev)
if (IS_ERR(phy_provider))
return PTR_ERR(phy_provider);
- dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
- if (IS_ERR(dsi->dmd)) {
- ret = PTR_ERR(dsi->dmd);
+ ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
+ if (ret < 0) {
if (ret != -EPROBE_DEFER)
DRM_DEV_ERROR(dev,
"Failed to probe dw_mipi_dsi: %d\n", ret);
diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
index d5f8c923d7bc..44dbbfc277d8 100644
--- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
+++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
@@ -518,9 +518,8 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, dsi);
- dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
- if (IS_ERR(dsi->dsi)) {
- ret = PTR_ERR(dsi->dsi);
+ ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data, &dsi->dsi);
+ if (ret < 0) {
dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
goto err_dsi_probe;
}
diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
index 65d5e68065e3..f073e819251e 100644
--- a/include/drm/bridge/dw_mipi_dsi.h
+++ b/include/drm/bridge/dw_mipi_dsi.h
@@ -76,9 +76,10 @@ struct dw_mipi_dsi_plat_data {
void *priv_data;
};
-struct dw_mipi_dsi *dw_mipi_dsi_probe(struct platform_device *pdev,
+int dw_mipi_dsi_probe(struct platform_device *pdev,
const struct dw_mipi_dsi_plat_data
- *plat_data);
+ *plat_data,
+ struct dw_mipi_dsi **dsi_p);
void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi);
int dw_mipi_dsi_bind(struct dw_mipi_dsi *dsi, struct drm_encoder *encoder);
void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi);
--
2.34.1
Hi,
On 12/01/2024 19:07, Farouk Bouabid wrote:
> dw-mipi-dsi based drivers such as dw-mipi-dsi-rockchip or dw_mipi_dsi-stm
> depend on dw_mipi_dsi_probe() to initialize the dw_mipi_dsi driver
> structure (dmd pointer). This structure is only initialized once
> dw_mipi_dsi_probe() returns, creating the link between the locally created
> structure and the actual dmd pointer.
>
> Probing the dsi host can be deferred in case of dependency to a dsi
> phy-supply (eg. "rockchip,px30-dsi-dphy"). Meanwhile dsi-device drivers
> like panels (eg. "ltk050h3146w") can already be registered on the bus.
> In that case, when attempting, to register the dsi host from
> dw_mipi_dsi_probe() using mipi_dsi_host_register(), the panel probe is
> called with a dsi-host pointer that is still locally allocated in
> dw_mipi_dsi_probe().
>
> While probing, the panel driver tries to attach to a dsi host
> (mipi_dsi_attach()) which calls in return for the specific dsi host
> attach hook. (e.g. dw_mipi_dsi_rockchip_host_attach()).
> dw_mipi_dsi_rockchip uses the component framework.
> In the attach hook, the host component is registered which calls in return
> for drm_bridge_attach() while trying to bind the component
> (dw_mipi_dsi_bind())
In meson_dw_mipi_dsi I simply fixed this by getting rid of components...
Neil
>
> drm_bridge_attach() requires a valid drm bridge parameter. However, the
> drm bridge (&dmd->bridge) that will be passed, is not yet initialized since
> the dw_mipi_dsi_probe() has not yet returned. This call will fail with a
> fatal error (invalid bridge) causing the panel to not be probed again.
>
> To simplify the issue: drm_bridge_attach() depends on the result pointer
> of dw_mipi_dsi_probe().
> While, if the dsi probe is deferred, drm_bridge_attach() is called before
> dw_mipi_dsi_probe() returns.
>
> drm_bridge_attach+0x14/0x1ac
> dw_mipi_dsi_bind+0x24/0x30
> dw_mipi_dsi_rockchip_bind+0x258/0x378
> component_bind_all+0x118/0x248
> rockchip_drm_bind+0xb0/0x1f8
> try_to_bring_up_aggregate_device+0x168/0x1d4
> __component_add+0xa4/0x170
> component_add+0x14/0x20
> dw_mipi_dsi_rockchip_host_attach+0x54/0x144
> dw_mipi_dsi_host_attach+0x9c/0xcc
> mipi_dsi_attach+0x28/0x3c
> ltk050h3146w_probe+0x10c/0x1a4
> mipi_dsi_drv_probe+0x20/0x2c
> really_probe+0x148/0x2ac
> __driver_probe_device+0x78/0x12c
> driver_probe_device+0xdc/0x160
> __device_attach_driver+0xb8/0x134
> bus_for_each_drv+0x80/0xdc
> __device_attach+0xa8/0x1b0
> device_initial_probe+0x14/0x20
> bus_probe_device+0xa8/0xac
> device_add+0x5cc/0x778
> mipi_dsi_device_register_full+0xd8/0x198
> mipi_dsi_host_register+0x98/0x18c
> __dw_mipi_dsi_probe+0x290/0x35c
> dw_mipi_dsi_probe+0x10/0x6c
> dw_mipi_dsi_rockchip_probe+0x208/0x3e4
> platform_probe+0x68/0xdc
> really_probe+0x148/0x2ac
> __driver_probe_device+0x78/0x12c
> driver_probe_device+0xdc/0x160
> __device_attach_driver+0xb8/0x134
> bus_for_each_drv+0x80/0xdc
> __device_attach+0xa8/0x1b0
> device_initial_probe+0x14/0x20
> bus_probe_device+0xa8/0xac
> deferred_probe_work_func+0x88/0xc0
> process_one_work+0x138/0x260
> worker_thread+0x32c/0x438
> kthread+0x118/0x11c
> ret_from_fork+0x10/0x20
> ---[ end trace 0000000000000000 ]---
>
> Fix this by initializing directly the dmd pointer in dw_mipi_dsi_probe(),
> which requires also initializting the dmd->bridge attributes that are
> required in drm_bridge_attach() before calling mipi_dsi_host_register().
>
> Signed-off-by: Farouk Bouabid <[email protected]>
> ---
> drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c | 4 +-
> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 42 ++++++++++---------
> drivers/gpu/drm/meson/meson_dw_mipi_dsi.c | 8 ++--
> .../gpu/drm/rockchip/dw-mipi-dsi-rockchip.c | 5 +--
> drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 5 +--
> include/drm/bridge/dw_mipi_dsi.h | 5 ++-
> 6 files changed, 35 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
> index 3ff30ce80c5b..469976ad3b19 100644
> --- a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
> @@ -881,8 +881,8 @@ static int imx93_dsi_probe(struct platform_device *pdev)
> dsi->pdata.priv_data = dsi;
> platform_set_drvdata(pdev, dsi);
>
> - dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
> - if (IS_ERR(dsi->dmd))
> + ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
> + if (ret < 0)
> return dev_err_probe(dev, PTR_ERR(dsi->dmd),
> "failed to probe dw_mipi_dsi\n");
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index 824fb3c65742..306cba366ba8 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -1184,18 +1184,19 @@ static void dw_mipi_dsi_debugfs_remove(struct dw_mipi_dsi *dsi) { }
>
> #endif /* CONFIG_DEBUG_FS */
>
> -static struct dw_mipi_dsi *
> -__dw_mipi_dsi_probe(struct platform_device *pdev,
> - const struct dw_mipi_dsi_plat_data *plat_data)
> +int __dw_mipi_dsi_probe(struct platform_device *pdev,
> + const struct dw_mipi_dsi_plat_data *plat_data, struct dw_mipi_dsi **dsi_p)
> {
> struct device *dev = &pdev->dev;
> struct reset_control *apb_rst;
> struct dw_mipi_dsi *dsi;
> int ret;
>
> - dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> - if (!dsi)
> - return ERR_PTR(-ENOMEM);
> + *dsi_p = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> + if (!*dsi_p)
> + return -ENOMEM;
> +
> + dsi = *dsi_p;
>
> dsi->dev = dev;
> dsi->plat_data = plat_data;
> @@ -1203,13 +1204,13 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps ||
> !plat_data->phy_ops->get_timing) {
> DRM_ERROR("Phy not properly configured\n");
> - return ERR_PTR(-ENODEV);
> + return -ENODEV;
> }
>
> if (!plat_data->base) {
> dsi->base = devm_platform_ioremap_resource(pdev, 0);
> if (IS_ERR(dsi->base))
> - return ERR_PTR(-ENODEV);
> + return -ENODEV;
>
> } else {
> dsi->base = plat_data->base;
> @@ -1219,7 +1220,7 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> if (IS_ERR(dsi->pclk)) {
> ret = PTR_ERR(dsi->pclk);
> dev_err(dev, "Unable to get pclk: %d\n", ret);
> - return ERR_PTR(ret);
> + return ret;
> }
>
> /*
> @@ -1233,14 +1234,14 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> if (ret != -EPROBE_DEFER)
> dev_err(dev, "Unable to get reset control: %d\n", ret);
>
> - return ERR_PTR(ret);
> + return ret;
> }
>
> if (apb_rst) {
> ret = clk_prepare_enable(dsi->pclk);
> if (ret) {
> dev_err(dev, "%s: Failed to enable pclk\n", __func__);
> - return ERR_PTR(ret);
> + return ret;
> }
>
> reset_control_assert(apb_rst);
> @@ -1255,19 +1256,20 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>
> dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
> dsi->dsi_host.dev = dev;
> + dsi->bridge.driver_private = dsi;
> + dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
> + dsi->bridge.of_node = pdev->dev.of_node;
> +
> ret = mipi_dsi_host_register(&dsi->dsi_host);
> if (ret) {
> dev_err(dev, "Failed to register MIPI host: %d\n", ret);
> pm_runtime_disable(dev);
> dw_mipi_dsi_debugfs_remove(dsi);
> - return ERR_PTR(ret);
> + return ret;
> }
>
> - dsi->bridge.driver_private = dsi;
> - dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
> - dsi->bridge.of_node = pdev->dev.of_node;
>
> - return dsi;
> + return 0;
> }
>
> static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
> @@ -1301,11 +1303,11 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_get_bridge);
> /*
> * Probe/remove API, used from platforms based on the DRM bridge API.
> */
> -struct dw_mipi_dsi *
> -dw_mipi_dsi_probe(struct platform_device *pdev,
> - const struct dw_mipi_dsi_plat_data *plat_data)
> +int dw_mipi_dsi_probe(struct platform_device *pdev,
> + const struct dw_mipi_dsi_plat_data *plat_data,
> + struct dw_mipi_dsi **dsi_p)
> {
> - return __dw_mipi_dsi_probe(pdev, plat_data);
> + return __dw_mipi_dsi_probe(pdev, plat_data, dsi_p);
> }
> EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
>
> diff --git a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
> index e5fe4e994f43..b103f3e31f2a 100644
> --- a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
> +++ b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
> @@ -262,6 +262,7 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
> {
> struct meson_dw_mipi_dsi *mipi_dsi;
> struct device *dev = &pdev->dev;
> + int ret;
>
> mipi_dsi = devm_kzalloc(dev, sizeof(*mipi_dsi), GFP_KERNEL);
> if (!mipi_dsi)
> @@ -315,10 +316,9 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
> mipi_dsi->pdata.priv_data = mipi_dsi;
> platform_set_drvdata(pdev, mipi_dsi);
>
> - mipi_dsi->dmd = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata);
> - if (IS_ERR(mipi_dsi->dmd))
> - return dev_err_probe(dev, PTR_ERR(mipi_dsi->dmd),
> - "Failed to probe dw_mipi_dsi\n");
> + ret = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata, &mipi_dsi->dmd);
> + if (ret < 0)
> + return dev_err_probe(dev, ret, "Failed to probe dw_mipi_dsi\n");
>
> return 0;
> }
> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
> index 6396f9324dab..4df32747476c 100644
> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
> @@ -1457,9 +1457,8 @@ static int dw_mipi_dsi_rockchip_probe(struct platform_device *pdev)
> if (IS_ERR(phy_provider))
> return PTR_ERR(phy_provider);
>
> - dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
> - if (IS_ERR(dsi->dmd)) {
> - ret = PTR_ERR(dsi->dmd);
> + ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
> + if (ret < 0) {
> if (ret != -EPROBE_DEFER)
> DRM_DEV_ERROR(dev,
> "Failed to probe dw_mipi_dsi: %d\n", ret);
> diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> index d5f8c923d7bc..44dbbfc277d8 100644
> --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> @@ -518,9 +518,8 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, dsi);
>
> - dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
> - if (IS_ERR(dsi->dsi)) {
> - ret = PTR_ERR(dsi->dsi);
> + ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data, &dsi->dsi);
> + if (ret < 0) {
> dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
> goto err_dsi_probe;
> }
> diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
> index 65d5e68065e3..f073e819251e 100644
> --- a/include/drm/bridge/dw_mipi_dsi.h
> +++ b/include/drm/bridge/dw_mipi_dsi.h
> @@ -76,9 +76,10 @@ struct dw_mipi_dsi_plat_data {
> void *priv_data;
> };
>
> -struct dw_mipi_dsi *dw_mipi_dsi_probe(struct platform_device *pdev,
> +int dw_mipi_dsi_probe(struct platform_device *pdev,
> const struct dw_mipi_dsi_plat_data
> - *plat_data);
> + *plat_data,
> + struct dw_mipi_dsi **dsi_p);
> void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi);
> int dw_mipi_dsi_bind(struct dw_mipi_dsi *dsi, struct drm_encoder *encoder);
> void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi);
Am Montag, 15. Januar 2024, 09:45:10 CET schrieb [email protected]:
> Hi,
>
> On 12/01/2024 19:07, Farouk Bouabid wrote:
> > dw-mipi-dsi based drivers such as dw-mipi-dsi-rockchip or dw_mipi_dsi-stm
> > depend on dw_mipi_dsi_probe() to initialize the dw_mipi_dsi driver
> > structure (dmd pointer). This structure is only initialized once
> > dw_mipi_dsi_probe() returns, creating the link between the locally created
> > structure and the actual dmd pointer.
> >
> > Probing the dsi host can be deferred in case of dependency to a dsi
> > phy-supply (eg. "rockchip,px30-dsi-dphy"). Meanwhile dsi-device drivers
> > like panels (eg. "ltk050h3146w") can already be registered on the bus.
> > In that case, when attempting, to register the dsi host from
> > dw_mipi_dsi_probe() using mipi_dsi_host_register(), the panel probe is
> > called with a dsi-host pointer that is still locally allocated in
> > dw_mipi_dsi_probe().
> >
> > While probing, the panel driver tries to attach to a dsi host
> > (mipi_dsi_attach()) which calls in return for the specific dsi host
> > attach hook. (e.g. dw_mipi_dsi_rockchip_host_attach()).
> > dw_mipi_dsi_rockchip uses the component framework.
> > In the attach hook, the host component is registered which calls in return
> > for drm_bridge_attach() while trying to bind the component
> > (dw_mipi_dsi_bind())
>
> In meson_dw_mipi_dsi I simply fixed this by getting rid of components...
If I remember correctly, the component element is there on Rockchip to
facilitate running dual-dsi displays (1 panel driven by 2 dsi controllers),
because it allows to wait for both controllers to have probed individually
before trying to drive the display.
Not sure if there is a better way to do that now.
Heiko
> > drm_bridge_attach() requires a valid drm bridge parameter. However, the
> > drm bridge (&dmd->bridge) that will be passed, is not yet initialized since
> > the dw_mipi_dsi_probe() has not yet returned. This call will fail with a
> > fatal error (invalid bridge) causing the panel to not be probed again.
> >
> > To simplify the issue: drm_bridge_attach() depends on the result pointer
> > of dw_mipi_dsi_probe().
> > While, if the dsi probe is deferred, drm_bridge_attach() is called before
> > dw_mipi_dsi_probe() returns.
> >
> > drm_bridge_attach+0x14/0x1ac
> > dw_mipi_dsi_bind+0x24/0x30
> > dw_mipi_dsi_rockchip_bind+0x258/0x378
> > component_bind_all+0x118/0x248
> > rockchip_drm_bind+0xb0/0x1f8
> > try_to_bring_up_aggregate_device+0x168/0x1d4
> > __component_add+0xa4/0x170
> > component_add+0x14/0x20
> > dw_mipi_dsi_rockchip_host_attach+0x54/0x144
> > dw_mipi_dsi_host_attach+0x9c/0xcc
> > mipi_dsi_attach+0x28/0x3c
> > ltk050h3146w_probe+0x10c/0x1a4
> > mipi_dsi_drv_probe+0x20/0x2c
> > really_probe+0x148/0x2ac
> > __driver_probe_device+0x78/0x12c
> > driver_probe_device+0xdc/0x160
> > __device_attach_driver+0xb8/0x134
> > bus_for_each_drv+0x80/0xdc
> > __device_attach+0xa8/0x1b0
> > device_initial_probe+0x14/0x20
> > bus_probe_device+0xa8/0xac
> > device_add+0x5cc/0x778
> > mipi_dsi_device_register_full+0xd8/0x198
> > mipi_dsi_host_register+0x98/0x18c
> > __dw_mipi_dsi_probe+0x290/0x35c
> > dw_mipi_dsi_probe+0x10/0x6c
> > dw_mipi_dsi_rockchip_probe+0x208/0x3e4
> > platform_probe+0x68/0xdc
> > really_probe+0x148/0x2ac
> > __driver_probe_device+0x78/0x12c
> > driver_probe_device+0xdc/0x160
> > __device_attach_driver+0xb8/0x134
> > bus_for_each_drv+0x80/0xdc
> > __device_attach+0xa8/0x1b0
> > device_initial_probe+0x14/0x20
> > bus_probe_device+0xa8/0xac
> > deferred_probe_work_func+0x88/0xc0
> > process_one_work+0x138/0x260
> > worker_thread+0x32c/0x438
> > kthread+0x118/0x11c
> > ret_from_fork+0x10/0x20
> > ---[ end trace 0000000000000000 ]---
> >
> > Fix this by initializing directly the dmd pointer in dw_mipi_dsi_probe(),
> > which requires also initializting the dmd->bridge attributes that are
> > required in drm_bridge_attach() before calling mipi_dsi_host_register().
> >
> > Signed-off-by: Farouk Bouabid <[email protected]>
> > ---
> > drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c | 4 +-
> > drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 42 ++++++++++---------
> > drivers/gpu/drm/meson/meson_dw_mipi_dsi.c | 8 ++--
> > .../gpu/drm/rockchip/dw-mipi-dsi-rockchip.c | 5 +--
> > drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 5 +--
> > include/drm/bridge/dw_mipi_dsi.h | 5 ++-
> > 6 files changed, 35 insertions(+), 34 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
> > index 3ff30ce80c5b..469976ad3b19 100644
> > --- a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
> > +++ b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
> > @@ -881,8 +881,8 @@ static int imx93_dsi_probe(struct platform_device *pdev)
> > dsi->pdata.priv_data = dsi;
> > platform_set_drvdata(pdev, dsi);
> >
> > - dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
> > - if (IS_ERR(dsi->dmd))
> > + ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
> > + if (ret < 0)
> > return dev_err_probe(dev, PTR_ERR(dsi->dmd),
> > "failed to probe dw_mipi_dsi\n");
> >
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> > index 824fb3c65742..306cba366ba8 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> > @@ -1184,18 +1184,19 @@ static void dw_mipi_dsi_debugfs_remove(struct dw_mipi_dsi *dsi) { }
> >
> > #endif /* CONFIG_DEBUG_FS */
> >
> > -static struct dw_mipi_dsi *
> > -__dw_mipi_dsi_probe(struct platform_device *pdev,
> > - const struct dw_mipi_dsi_plat_data *plat_data)
> > +int __dw_mipi_dsi_probe(struct platform_device *pdev,
> > + const struct dw_mipi_dsi_plat_data *plat_data, struct dw_mipi_dsi **dsi_p)
> > {
> > struct device *dev = &pdev->dev;
> > struct reset_control *apb_rst;
> > struct dw_mipi_dsi *dsi;
> > int ret;
> >
> > - dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> > - if (!dsi)
> > - return ERR_PTR(-ENOMEM);
> > + *dsi_p = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> > + if (!*dsi_p)
> > + return -ENOMEM;
> > +
> > + dsi = *dsi_p;
> >
> > dsi->dev = dev;
> > dsi->plat_data = plat_data;
> > @@ -1203,13 +1204,13 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> > if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps ||
> > !plat_data->phy_ops->get_timing) {
> > DRM_ERROR("Phy not properly configured\n");
> > - return ERR_PTR(-ENODEV);
> > + return -ENODEV;
> > }
> >
> > if (!plat_data->base) {
> > dsi->base = devm_platform_ioremap_resource(pdev, 0);
> > if (IS_ERR(dsi->base))
> > - return ERR_PTR(-ENODEV);
> > + return -ENODEV;
> >
> > } else {
> > dsi->base = plat_data->base;
> > @@ -1219,7 +1220,7 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> > if (IS_ERR(dsi->pclk)) {
> > ret = PTR_ERR(dsi->pclk);
> > dev_err(dev, "Unable to get pclk: %d\n", ret);
> > - return ERR_PTR(ret);
> > + return ret;
> > }
> >
> > /*
> > @@ -1233,14 +1234,14 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> > if (ret != -EPROBE_DEFER)
> > dev_err(dev, "Unable to get reset control: %d\n", ret);
> >
> > - return ERR_PTR(ret);
> > + return ret;
> > }
> >
> > if (apb_rst) {
> > ret = clk_prepare_enable(dsi->pclk);
> > if (ret) {
> > dev_err(dev, "%s: Failed to enable pclk\n", __func__);
> > - return ERR_PTR(ret);
> > + return ret;
> > }
> >
> > reset_control_assert(apb_rst);
> > @@ -1255,19 +1256,20 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
> >
> > dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
> > dsi->dsi_host.dev = dev;
> > + dsi->bridge.driver_private = dsi;
> > + dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
> > + dsi->bridge.of_node = pdev->dev.of_node;
> > +
> > ret = mipi_dsi_host_register(&dsi->dsi_host);
> > if (ret) {
> > dev_err(dev, "Failed to register MIPI host: %d\n", ret);
> > pm_runtime_disable(dev);
> > dw_mipi_dsi_debugfs_remove(dsi);
> > - return ERR_PTR(ret);
> > + return ret;
> > }
> >
> > - dsi->bridge.driver_private = dsi;
> > - dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
> > - dsi->bridge.of_node = pdev->dev.of_node;
> >
> > - return dsi;
> > + return 0;
> > }
> >
> > static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
> > @@ -1301,11 +1303,11 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_get_bridge);
> > /*
> > * Probe/remove API, used from platforms based on the DRM bridge API.
> > */
> > -struct dw_mipi_dsi *
> > -dw_mipi_dsi_probe(struct platform_device *pdev,
> > - const struct dw_mipi_dsi_plat_data *plat_data)
> > +int dw_mipi_dsi_probe(struct platform_device *pdev,
> > + const struct dw_mipi_dsi_plat_data *plat_data,
> > + struct dw_mipi_dsi **dsi_p)
> > {
> > - return __dw_mipi_dsi_probe(pdev, plat_data);
> > + return __dw_mipi_dsi_probe(pdev, plat_data, dsi_p);
> > }
> > EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
> >
> > diff --git a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
> > index e5fe4e994f43..b103f3e31f2a 100644
> > --- a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
> > +++ b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
> > @@ -262,6 +262,7 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
> > {
> > struct meson_dw_mipi_dsi *mipi_dsi;
> > struct device *dev = &pdev->dev;
> > + int ret;
> >
> > mipi_dsi = devm_kzalloc(dev, sizeof(*mipi_dsi), GFP_KERNEL);
> > if (!mipi_dsi)
> > @@ -315,10 +316,9 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
> > mipi_dsi->pdata.priv_data = mipi_dsi;
> > platform_set_drvdata(pdev, mipi_dsi);
> >
> > - mipi_dsi->dmd = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata);
> > - if (IS_ERR(mipi_dsi->dmd))
> > - return dev_err_probe(dev, PTR_ERR(mipi_dsi->dmd),
> > - "Failed to probe dw_mipi_dsi\n");
> > + ret = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata, &mipi_dsi->dmd);
> > + if (ret < 0)
> > + return dev_err_probe(dev, ret, "Failed to probe dw_mipi_dsi\n");
> >
> > return 0;
> > }
> > diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
> > index 6396f9324dab..4df32747476c 100644
> > --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
> > +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
> > @@ -1457,9 +1457,8 @@ static int dw_mipi_dsi_rockchip_probe(struct platform_device *pdev)
> > if (IS_ERR(phy_provider))
> > return PTR_ERR(phy_provider);
> >
> > - dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
> > - if (IS_ERR(dsi->dmd)) {
> > - ret = PTR_ERR(dsi->dmd);
> > + ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
> > + if (ret < 0) {
> > if (ret != -EPROBE_DEFER)
> > DRM_DEV_ERROR(dev,
> > "Failed to probe dw_mipi_dsi: %d\n", ret);
> > diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> > index d5f8c923d7bc..44dbbfc277d8 100644
> > --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> > +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> > @@ -518,9 +518,8 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
> >
> > platform_set_drvdata(pdev, dsi);
> >
> > - dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
> > - if (IS_ERR(dsi->dsi)) {
> > - ret = PTR_ERR(dsi->dsi);
> > + ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data, &dsi->dsi);
> > + if (ret < 0) {
> > dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
> > goto err_dsi_probe;
> > }
> > diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
> > index 65d5e68065e3..f073e819251e 100644
> > --- a/include/drm/bridge/dw_mipi_dsi.h
> > +++ b/include/drm/bridge/dw_mipi_dsi.h
> > @@ -76,9 +76,10 @@ struct dw_mipi_dsi_plat_data {
> > void *priv_data;
> > };
> >
> > -struct dw_mipi_dsi *dw_mipi_dsi_probe(struct platform_device *pdev,
> > +int dw_mipi_dsi_probe(struct platform_device *pdev,
> > const struct dw_mipi_dsi_plat_data
> > - *plat_data);
> > + *plat_data,
> > + struct dw_mipi_dsi **dsi_p);
> > void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi);
> > int dw_mipi_dsi_bind(struct dw_mipi_dsi *dsi, struct drm_encoder *encoder);
> > void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi);
>
>
On 15/01/2024 11:07, Heiko Stübner wrote:
> Am Montag, 15. Januar 2024, 09:45:10 CET schrieb [email protected]:
>> Hi,
>>
>> On 12/01/2024 19:07, Farouk Bouabid wrote:
>>> dw-mipi-dsi based drivers such as dw-mipi-dsi-rockchip or dw_mipi_dsi-stm
>>> depend on dw_mipi_dsi_probe() to initialize the dw_mipi_dsi driver
>>> structure (dmd pointer). This structure is only initialized once
>>> dw_mipi_dsi_probe() returns, creating the link between the locally created
>>> structure and the actual dmd pointer.
>>>
>>> Probing the dsi host can be deferred in case of dependency to a dsi
>>> phy-supply (eg. "rockchip,px30-dsi-dphy"). Meanwhile dsi-device drivers
>>> like panels (eg. "ltk050h3146w") can already be registered on the bus.
>>> In that case, when attempting, to register the dsi host from
>>> dw_mipi_dsi_probe() using mipi_dsi_host_register(), the panel probe is
>>> called with a dsi-host pointer that is still locally allocated in
>>> dw_mipi_dsi_probe().
>>>
>>> While probing, the panel driver tries to attach to a dsi host
>>> (mipi_dsi_attach()) which calls in return for the specific dsi host
>>> attach hook. (e.g. dw_mipi_dsi_rockchip_host_attach()).
>>> dw_mipi_dsi_rockchip uses the component framework.
>>> In the attach hook, the host component is registered which calls in return
>>> for drm_bridge_attach() while trying to bind the component
>>> (dw_mipi_dsi_bind())
>>
>> In meson_dw_mipi_dsi I simply fixed this by getting rid of components...
>
> If I remember correctly, the component element is there on Rockchip to
> facilitate running dual-dsi displays (1 panel driven by 2 dsi controllers),
> because it allows to wait for both controllers to have probed individually
> before trying to drive the display.
>
> Not sure if there is a better way to do that now.
Device links should limit probe deferal to a minimum, at least it works fine
on the systems I work on
Neil
>
>
> Heiko
>
>
>>> drm_bridge_attach() requires a valid drm bridge parameter. However, the
>>> drm bridge (&dmd->bridge) that will be passed, is not yet initialized since
>>> the dw_mipi_dsi_probe() has not yet returned. This call will fail with a
>>> fatal error (invalid bridge) causing the panel to not be probed again.
>>>
>>> To simplify the issue: drm_bridge_attach() depends on the result pointer
>>> of dw_mipi_dsi_probe().
>>> While, if the dsi probe is deferred, drm_bridge_attach() is called before
>>> dw_mipi_dsi_probe() returns.
>>>
>>> drm_bridge_attach+0x14/0x1ac
>>> dw_mipi_dsi_bind+0x24/0x30
>>> dw_mipi_dsi_rockchip_bind+0x258/0x378
>>> component_bind_all+0x118/0x248
>>> rockchip_drm_bind+0xb0/0x1f8
>>> try_to_bring_up_aggregate_device+0x168/0x1d4
>>> __component_add+0xa4/0x170
>>> component_add+0x14/0x20
>>> dw_mipi_dsi_rockchip_host_attach+0x54/0x144
>>> dw_mipi_dsi_host_attach+0x9c/0xcc
>>> mipi_dsi_attach+0x28/0x3c
>>> ltk050h3146w_probe+0x10c/0x1a4
>>> mipi_dsi_drv_probe+0x20/0x2c
>>> really_probe+0x148/0x2ac
>>> __driver_probe_device+0x78/0x12c
>>> driver_probe_device+0xdc/0x160
>>> __device_attach_driver+0xb8/0x134
>>> bus_for_each_drv+0x80/0xdc
>>> __device_attach+0xa8/0x1b0
>>> device_initial_probe+0x14/0x20
>>> bus_probe_device+0xa8/0xac
>>> device_add+0x5cc/0x778
>>> mipi_dsi_device_register_full+0xd8/0x198
>>> mipi_dsi_host_register+0x98/0x18c
>>> __dw_mipi_dsi_probe+0x290/0x35c
>>> dw_mipi_dsi_probe+0x10/0x6c
>>> dw_mipi_dsi_rockchip_probe+0x208/0x3e4
>>> platform_probe+0x68/0xdc
>>> really_probe+0x148/0x2ac
>>> __driver_probe_device+0x78/0x12c
>>> driver_probe_device+0xdc/0x160
>>> __device_attach_driver+0xb8/0x134
>>> bus_for_each_drv+0x80/0xdc
>>> __device_attach+0xa8/0x1b0
>>> device_initial_probe+0x14/0x20
>>> bus_probe_device+0xa8/0xac
>>> deferred_probe_work_func+0x88/0xc0
>>> process_one_work+0x138/0x260
>>> worker_thread+0x32c/0x438
>>> kthread+0x118/0x11c
>>> ret_from_fork+0x10/0x20
>>> ---[ end trace 0000000000000000 ]---
>>>
>>> Fix this by initializing directly the dmd pointer in dw_mipi_dsi_probe(),
>>> which requires also initializting the dmd->bridge attributes that are
>>> required in drm_bridge_attach() before calling mipi_dsi_host_register().
>>>
>>> Signed-off-by: Farouk Bouabid <[email protected]>
>>> ---
>>> drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c | 4 +-
>>> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 42 ++++++++++---------
>>> drivers/gpu/drm/meson/meson_dw_mipi_dsi.c | 8 ++--
>>> .../gpu/drm/rockchip/dw-mipi-dsi-rockchip.c | 5 +--
>>> drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 5 +--
>>> include/drm/bridge/dw_mipi_dsi.h | 5 ++-
>>> 6 files changed, 35 insertions(+), 34 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
>>> index 3ff30ce80c5b..469976ad3b19 100644
>>> --- a/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
>>> +++ b/drivers/gpu/drm/bridge/imx/imx93-mipi-dsi.c
>>> @@ -881,8 +881,8 @@ static int imx93_dsi_probe(struct platform_device *pdev)
>>> dsi->pdata.priv_data = dsi;
>>> platform_set_drvdata(pdev, dsi);
>>>
>>> - dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
>>> - if (IS_ERR(dsi->dmd))
>>> + ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
>>> + if (ret < 0)
>>> return dev_err_probe(dev, PTR_ERR(dsi->dmd),
>>> "failed to probe dw_mipi_dsi\n");
>>>
>>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>> index 824fb3c65742..306cba366ba8 100644
>>> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>> @@ -1184,18 +1184,19 @@ static void dw_mipi_dsi_debugfs_remove(struct dw_mipi_dsi *dsi) { }
>>>
>>> #endif /* CONFIG_DEBUG_FS */
>>>
>>> -static struct dw_mipi_dsi *
>>> -__dw_mipi_dsi_probe(struct platform_device *pdev,
>>> - const struct dw_mipi_dsi_plat_data *plat_data)
>>> +int __dw_mipi_dsi_probe(struct platform_device *pdev,
>>> + const struct dw_mipi_dsi_plat_data *plat_data, struct dw_mipi_dsi **dsi_p)
>>> {
>>> struct device *dev = &pdev->dev;
>>> struct reset_control *apb_rst;
>>> struct dw_mipi_dsi *dsi;
>>> int ret;
>>>
>>> - dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
>>> - if (!dsi)
>>> - return ERR_PTR(-ENOMEM);
>>> + *dsi_p = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
>>> + if (!*dsi_p)
>>> + return -ENOMEM;
>>> +
>>> + dsi = *dsi_p;
>>>
>>> dsi->dev = dev;
>>> dsi->plat_data = plat_data;
>>> @@ -1203,13 +1204,13 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>>> if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps ||
>>> !plat_data->phy_ops->get_timing) {
>>> DRM_ERROR("Phy not properly configured\n");
>>> - return ERR_PTR(-ENODEV);
>>> + return -ENODEV;
>>> }
>>>
>>> if (!plat_data->base) {
>>> dsi->base = devm_platform_ioremap_resource(pdev, 0);
>>> if (IS_ERR(dsi->base))
>>> - return ERR_PTR(-ENODEV);
>>> + return -ENODEV;
>>>
>>> } else {
>>> dsi->base = plat_data->base;
>>> @@ -1219,7 +1220,7 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>>> if (IS_ERR(dsi->pclk)) {
>>> ret = PTR_ERR(dsi->pclk);
>>> dev_err(dev, "Unable to get pclk: %d\n", ret);
>>> - return ERR_PTR(ret);
>>> + return ret;
>>> }
>>>
>>> /*
>>> @@ -1233,14 +1234,14 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>>> if (ret != -EPROBE_DEFER)
>>> dev_err(dev, "Unable to get reset control: %d\n", ret);
>>>
>>> - return ERR_PTR(ret);
>>> + return ret;
>>> }
>>>
>>> if (apb_rst) {
>>> ret = clk_prepare_enable(dsi->pclk);
>>> if (ret) {
>>> dev_err(dev, "%s: Failed to enable pclk\n", __func__);
>>> - return ERR_PTR(ret);
>>> + return ret;
>>> }
>>>
>>> reset_control_assert(apb_rst);
>>> @@ -1255,19 +1256,20 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>>>
>>> dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
>>> dsi->dsi_host.dev = dev;
>>> + dsi->bridge.driver_private = dsi;
>>> + dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
>>> + dsi->bridge.of_node = pdev->dev.of_node;
>>> +
>>> ret = mipi_dsi_host_register(&dsi->dsi_host);
>>> if (ret) {
>>> dev_err(dev, "Failed to register MIPI host: %d\n", ret);
>>> pm_runtime_disable(dev);
>>> dw_mipi_dsi_debugfs_remove(dsi);
>>> - return ERR_PTR(ret);
>>> + return ret;
>>> }
>>>
>>> - dsi->bridge.driver_private = dsi;
>>> - dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
>>> - dsi->bridge.of_node = pdev->dev.of_node;
>>>
>>> - return dsi;
>>> + return 0;
>>> }
>>>
>>> static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
>>> @@ -1301,11 +1303,11 @@ EXPORT_SYMBOL_GPL(dw_mipi_dsi_get_bridge);
>>> /*
>>> * Probe/remove API, used from platforms based on the DRM bridge API.
>>> */
>>> -struct dw_mipi_dsi *
>>> -dw_mipi_dsi_probe(struct platform_device *pdev,
>>> - const struct dw_mipi_dsi_plat_data *plat_data)
>>> +int dw_mipi_dsi_probe(struct platform_device *pdev,
>>> + const struct dw_mipi_dsi_plat_data *plat_data,
>>> + struct dw_mipi_dsi **dsi_p)
>>> {
>>> - return __dw_mipi_dsi_probe(pdev, plat_data);
>>> + return __dw_mipi_dsi_probe(pdev, plat_data, dsi_p);
>>> }
>>> EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
>>>
>>> diff --git a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
>>> index e5fe4e994f43..b103f3e31f2a 100644
>>> --- a/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
>>> +++ b/drivers/gpu/drm/meson/meson_dw_mipi_dsi.c
>>> @@ -262,6 +262,7 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
>>> {
>>> struct meson_dw_mipi_dsi *mipi_dsi;
>>> struct device *dev = &pdev->dev;
>>> + int ret;
>>>
>>> mipi_dsi = devm_kzalloc(dev, sizeof(*mipi_dsi), GFP_KERNEL);
>>> if (!mipi_dsi)
>>> @@ -315,10 +316,9 @@ static int meson_dw_mipi_dsi_probe(struct platform_device *pdev)
>>> mipi_dsi->pdata.priv_data = mipi_dsi;
>>> platform_set_drvdata(pdev, mipi_dsi);
>>>
>>> - mipi_dsi->dmd = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata);
>>> - if (IS_ERR(mipi_dsi->dmd))
>>> - return dev_err_probe(dev, PTR_ERR(mipi_dsi->dmd),
>>> - "Failed to probe dw_mipi_dsi\n");
>>> + ret = dw_mipi_dsi_probe(pdev, &mipi_dsi->pdata, &mipi_dsi->dmd);
>>> + if (ret < 0)
>>> + return dev_err_probe(dev, ret, "Failed to probe dw_mipi_dsi\n");
>>>
>>> return 0;
>>> }
>>> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
>>> index 6396f9324dab..4df32747476c 100644
>>> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
>>> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi-rockchip.c
>>> @@ -1457,9 +1457,8 @@ static int dw_mipi_dsi_rockchip_probe(struct platform_device *pdev)
>>> if (IS_ERR(phy_provider))
>>> return PTR_ERR(phy_provider);
>>>
>>> - dsi->dmd = dw_mipi_dsi_probe(pdev, &dsi->pdata);
>>> - if (IS_ERR(dsi->dmd)) {
>>> - ret = PTR_ERR(dsi->dmd);
>>> + ret = dw_mipi_dsi_probe(pdev, &dsi->pdata, &dsi->dmd);
>>> + if (ret < 0) {
>>> if (ret != -EPROBE_DEFER)
>>> DRM_DEV_ERROR(dev,
>>> "Failed to probe dw_mipi_dsi: %d\n", ret);
>>> diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>> index d5f8c923d7bc..44dbbfc277d8 100644
>>> --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>> +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
>>> @@ -518,9 +518,8 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>>>
>>> platform_set_drvdata(pdev, dsi);
>>>
>>> - dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
>>> - if (IS_ERR(dsi->dsi)) {
>>> - ret = PTR_ERR(dsi->dsi);
>>> + ret = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data, &dsi->dsi);
>>> + if (ret < 0) {
>>> dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
>>> goto err_dsi_probe;
>>> }
>>> diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
>>> index 65d5e68065e3..f073e819251e 100644
>>> --- a/include/drm/bridge/dw_mipi_dsi.h
>>> +++ b/include/drm/bridge/dw_mipi_dsi.h
>>> @@ -76,9 +76,10 @@ struct dw_mipi_dsi_plat_data {
>>> void *priv_data;
>>> };
>>>
>>> -struct dw_mipi_dsi *dw_mipi_dsi_probe(struct platform_device *pdev,
>>> +int dw_mipi_dsi_probe(struct platform_device *pdev,
>>> const struct dw_mipi_dsi_plat_data
>>> - *plat_data);
>>> + *plat_data,
>>> + struct dw_mipi_dsi **dsi_p);
>>> void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi);
>>> int dw_mipi_dsi_bind(struct dw_mipi_dsi *dsi, struct drm_encoder *encoder);
>>> void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi);
>>
>>
>
>
>
>
Hi Farouk,
kernel test robot noticed the following build warnings:
[auto build test WARNING on drm-misc/drm-misc-next]
[also build test WARNING on drm/drm-next linus/master v6.7 next-20240112]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Farouk-Bouabid/drm-bridge-synopsys-dw-mipi-dsi-fix-deferred-dsi-host-probe-breaks-dsi-device-probe/20240113-020945
base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link: https://lore.kernel.org/r/20240112180737.551318-1-farouk.bouabid%40theobroma-systems.com
patch subject: [PATCH] drm/bridge: synopsys: dw-mipi-dsi: fix deferred dsi host probe breaks dsi device probe
config: i386-buildonly-randconfig-002-20240115 (https://download.01.org/0day-ci/archive/20240116/[email protected]/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240116/[email protected]/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All warnings (new ones prefixed by >>):
>> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c:1187:5: warning: no previous prototype for '__dw_mipi_dsi_probe' [-Wmissing-prototypes]
1187 | int __dw_mipi_dsi_probe(struct platform_device *pdev,
| ^~~~~~~~~~~~~~~~~~~
vim +/__dw_mipi_dsi_probe +1187 drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
1186
> 1187 int __dw_mipi_dsi_probe(struct platform_device *pdev,
1188 const struct dw_mipi_dsi_plat_data *plat_data, struct dw_mipi_dsi **dsi_p)
1189 {
1190 struct device *dev = &pdev->dev;
1191 struct reset_control *apb_rst;
1192 struct dw_mipi_dsi *dsi;
1193 int ret;
1194
1195 *dsi_p = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
1196 if (!*dsi_p)
1197 return -ENOMEM;
1198
1199 dsi = *dsi_p;
1200
1201 dsi->dev = dev;
1202 dsi->plat_data = plat_data;
1203
1204 if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps ||
1205 !plat_data->phy_ops->get_timing) {
1206 DRM_ERROR("Phy not properly configured\n");
1207 return -ENODEV;
1208 }
1209
1210 if (!plat_data->base) {
1211 dsi->base = devm_platform_ioremap_resource(pdev, 0);
1212 if (IS_ERR(dsi->base))
1213 return -ENODEV;
1214
1215 } else {
1216 dsi->base = plat_data->base;
1217 }
1218
1219 dsi->pclk = devm_clk_get(dev, "pclk");
1220 if (IS_ERR(dsi->pclk)) {
1221 ret = PTR_ERR(dsi->pclk);
1222 dev_err(dev, "Unable to get pclk: %d\n", ret);
1223 return ret;
1224 }
1225
1226 /*
1227 * Note that the reset was not defined in the initial device tree, so
1228 * we have to be prepared for it not being found.
1229 */
1230 apb_rst = devm_reset_control_get_optional_exclusive(dev, "apb");
1231 if (IS_ERR(apb_rst)) {
1232 ret = PTR_ERR(apb_rst);
1233
1234 if (ret != -EPROBE_DEFER)
1235 dev_err(dev, "Unable to get reset control: %d\n", ret);
1236
1237 return ret;
1238 }
1239
1240 if (apb_rst) {
1241 ret = clk_prepare_enable(dsi->pclk);
1242 if (ret) {
1243 dev_err(dev, "%s: Failed to enable pclk\n", __func__);
1244 return ret;
1245 }
1246
1247 reset_control_assert(apb_rst);
1248 usleep_range(10, 20);
1249 reset_control_deassert(apb_rst);
1250
1251 clk_disable_unprepare(dsi->pclk);
1252 }
1253
1254 dw_mipi_dsi_debugfs_init(dsi);
1255 pm_runtime_enable(dev);
1256
1257 dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
1258 dsi->dsi_host.dev = dev;
1259 dsi->bridge.driver_private = dsi;
1260 dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
1261 dsi->bridge.of_node = pdev->dev.of_node;
1262
1263 ret = mipi_dsi_host_register(&dsi->dsi_host);
1264 if (ret) {
1265 dev_err(dev, "Failed to register MIPI host: %d\n", ret);
1266 pm_runtime_disable(dev);
1267 dw_mipi_dsi_debugfs_remove(dsi);
1268 return ret;
1269 }
1270
1271
1272 return 0;
1273 }
1274
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki