Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
---
drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
1 file changed, 45 insertions(+), 19 deletions(-)
diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
index ea19de5509ed..a567f136ddc7 100644
--- a/drivers/gpu/drm/bridge/tc358768.c
+++ b/drivers/gpu/drm/bridge/tc358768.c
@@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
struct tc358768_dsi_output {
struct mipi_dsi_device *dev;
+
+ /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
struct drm_panel *panel;
- struct drm_bridge *bridge;
+
+ /*
+ * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
+ * to tc358768, 'next_bridge' contains the bridge the driver created
+ * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
+ * the next bridge the driver found.
+ */
+ struct drm_bridge *next_bridge;
};
struct tc358768_priv {
@@ -391,8 +400,6 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
struct mipi_dsi_device *dev)
{
struct tc358768_priv *priv = dsi_host_to_tc358768(host);
- struct drm_bridge *bridge;
- struct drm_panel *panel;
struct device_node *ep;
int ret;
@@ -420,21 +427,7 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
return -ENOTSUPP;
}
- ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
- &bridge);
- if (ret)
- return ret;
-
- if (panel) {
- bridge = drm_panel_bridge_add_typed(panel,
- DRM_MODE_CONNECTOR_DSI);
- if (IS_ERR(bridge))
- return PTR_ERR(bridge);
- }
-
priv->output.dev = dev;
- priv->output.bridge = bridge;
- priv->output.panel = panel;
priv->dsi_lanes = dev->lanes;
priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
@@ -463,7 +456,7 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
drm_bridge_remove(&priv->bridge);
if (priv->output.panel)
- drm_panel_bridge_remove(priv->output.bridge);
+ drm_panel_bridge_remove(priv->output.next_bridge);
return 0;
}
@@ -544,7 +537,40 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
return -ENOTSUPP;
}
- return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
+ if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
+ struct device_node *node;
+
+ /* Get the next bridge, connected to port@1. */
+ node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
+ if (!node)
+ return -ENODEV;
+
+ priv->output.next_bridge = of_drm_find_bridge(node);
+ of_node_put(node);
+ if (!priv->output.next_bridge)
+ return -EPROBE_DEFER;
+ } else {
+ struct drm_bridge *bridge;
+ struct drm_panel *panel;
+ int ret;
+
+ ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
+ &panel, &bridge);
+ if (ret)
+ return ret;
+
+ if (panel) {
+ bridge = drm_panel_bridge_add_typed(panel,
+ DRM_MODE_CONNECTOR_DSI);
+ if (IS_ERR(bridge))
+ return PTR_ERR(bridge);
+ }
+
+ priv->output.next_bridge = bridge;
+ priv->output.panel = panel;
+ }
+
+ return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
flags);
}
--
2.34.1On 04.08.23 12:44, Tomi Valkeinen wrote:
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> ---
> drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
> 1 file changed, 45 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
> index ea19de5509ed..a567f136ddc7 100644
> --- a/drivers/gpu/drm/bridge/tc358768.c
> +++ b/drivers/gpu/drm/bridge/tc358768.c
> @@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
>
> struct tc358768_dsi_output {
> struct mipi_dsi_device *dev;
> +
> + /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
> struct drm_panel *panel;
> - struct drm_bridge *bridge;
> +
> + /*
> + * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
> + * to tc358768, 'next_bridge' contains the bridge the driver created
> + * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
> + * the next bridge the driver found.
> + */
> + struct drm_bridge *next_bridge;
> };
>
> struct tc358768_priv {
> @@ -391,8 +400,6 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
> struct mipi_dsi_device *dev)
> {
> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
> - struct drm_bridge *bridge;
> - struct drm_panel *panel;
> struct device_node *ep;
> int ret;
>
> @@ -420,21 +427,7 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
> return -ENOTSUPP;
> }
>
> - ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
> - &bridge);
> - if (ret)
> - return ret;
> -
> - if (panel) {
> - bridge = drm_panel_bridge_add_typed(panel,
> - DRM_MODE_CONNECTOR_DSI);
> - if (IS_ERR(bridge))
> - return PTR_ERR(bridge);
> - }
> -
> priv->output.dev = dev;
> - priv->output.bridge = bridge;
> - priv->output.panel = panel;
>
> priv->dsi_lanes = dev->lanes;
> priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
> @@ -463,7 +456,7 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
>
> drm_bridge_remove(&priv->bridge);
> if (priv->output.panel)
> - drm_panel_bridge_remove(priv->output.bridge);
> + drm_panel_bridge_remove(priv->output.next_bridge);
>
> return 0;
> }
> @@ -544,7 +537,40 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
> return -ENOTSUPP;
> }
>
> - return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
> + struct device_node *node;
> +
> + /* Get the next bridge, connected to port@1. */
> + node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
> + if (!node)
> + return -ENODEV;
> +
> + priv->output.next_bridge = of_drm_find_bridge(node);
> + of_node_put(node);
> + if (!priv->output.next_bridge)
> + return -EPROBE_DEFER;
> + } else {
> + struct drm_bridge *bridge;
> + struct drm_panel *panel;
> + int ret;
> +
> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
> + &panel, &bridge);
> + if (ret)
> + return ret;
> +
> + if (panel) {
> + bridge = drm_panel_bridge_add_typed(panel,
> + DRM_MODE_CONNECTOR_DSI);
> + if (IS_ERR(bridge))
> + return PTR_ERR(bridge);
> + }
> +
> + priv->output.next_bridge = bridge;
> + priv->output.panel = panel;
> + }
> +
> + return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
> flags);
> }
>
>
This patch unfortunately breaks the display output on the Asus TF700T:
[drm:drm_bridge_attach] *ERROR* failed to attach bridge /i2c-mux/i2c@1/dsi@7 to encoder LVDS-59: -517
tegra-dc 54200000.dc: failed to initialize RGB output: -517
drm drm: failed to initialize 54200000.dc: -517
------------[ cut here ]------------
WARNING: CPU: 3 PID: 69 at lib/refcount.c:28 tegra_dc_init+0x24/0x5fc
refcount_t: underflow; use-after-free.
Modules linked in: elants_i2c panel_simple tc358768 atkbd vivaldi_fmap
CPU: 3 PID: 69 Comm: kworker/u8:6 Not tainted 6.5.0-rc2-postmarketos-grate #95
Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
Workqueue: events_unbound deferred_probe_work_func
unwind_backtrace from show_stack+0x10/0x14
show_stack from dump_stack_lvl+0x40/0x4c
dump_stack_lvl from __warn+0x94/0xc0
__warn from warn_slowpath_fmt+0x118/0x16c
warn_slowpath_fmt from tegra_dc_init+0x24/0x5fc
tegra_dc_init from host1x_device_init+0x84/0x15c
host1x_device_init from host1x_drm_probe+0xd8/0x3c4
host1x_drm_probe from really_probe+0xc8/0x2dc
really_probe from __driver_probe_device+0x88/0x19c
__driver_probe_device from driver_probe_device+0x30/0x104
driver_probe_device from __device_attach_driver+0x94/0x108
__device_attach_driver from bus_for_each_drv+0x80/0xb8
bus_for_each_drv from __device_attach+0xa0/0x190
__device_attach from bus_probe_device+0x88/0x8c
bus_probe_device from deferred_probe_work_func+0x78/0xa4
deferred_probe_work_func from process_one_work+0x208/0x420
process_one_work from worker_thread+0x54/0x550
worker_thread from kthread+0xdc/0xf8
kthread from ret_from_fork+0x14/0x2c
Exception stack(0xcf9c5fb0 to 0xcf9c5ff8)
5fa0: 00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
---[ end trace 0000000000000000 ]---
Best regards,
Maxim
On 13/08/2023 20:11, Maxim Schwalm wrote:
> On 04.08.23 12:44, Tomi Valkeinen wrote:
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> ---
>> drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
>> 1 file changed, 45 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
>> index ea19de5509ed..a567f136ddc7 100644
>> --- a/drivers/gpu/drm/bridge/tc358768.c
>> +++ b/drivers/gpu/drm/bridge/tc358768.c
>> @@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
>>
>> struct tc358768_dsi_output {
>> struct mipi_dsi_device *dev;
>> +
>> + /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
>> struct drm_panel *panel;
>> - struct drm_bridge *bridge;
>> +
>> + /*
>> + * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
>> + * to tc358768, 'next_bridge' contains the bridge the driver created
>> + * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
>> + * the next bridge the driver found.
>> + */
>> + struct drm_bridge *next_bridge;
>> };
>>
>> struct tc358768_priv {
>> @@ -391,8 +400,6 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
>> struct mipi_dsi_device *dev)
>> {
>> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
>> - struct drm_bridge *bridge;
>> - struct drm_panel *panel;
>> struct device_node *ep;
>> int ret;
>>
>> @@ -420,21 +427,7 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
>> return -ENOTSUPP;
>> }
>>
>> - ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
>> - &bridge);
>> - if (ret)
>> - return ret;
>> -
>> - if (panel) {
>> - bridge = drm_panel_bridge_add_typed(panel,
>> - DRM_MODE_CONNECTOR_DSI);
>> - if (IS_ERR(bridge))
>> - return PTR_ERR(bridge);
>> - }
>> -
>> priv->output.dev = dev;
>> - priv->output.bridge = bridge;
>> - priv->output.panel = panel;
>>
>> priv->dsi_lanes = dev->lanes;
>> priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
>> @@ -463,7 +456,7 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
>>
>> drm_bridge_remove(&priv->bridge);
>> if (priv->output.panel)
>> - drm_panel_bridge_remove(priv->output.bridge);
>> + drm_panel_bridge_remove(priv->output.next_bridge);
>>
>> return 0;
>> }
>> @@ -544,7 +537,40 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
>> return -ENOTSUPP;
>> }
>>
>> - return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
>> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
>> + struct device_node *node;
>> +
>> + /* Get the next bridge, connected to port@1. */
>> + node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
>> + if (!node)
>> + return -ENODEV;
>> +
>> + priv->output.next_bridge = of_drm_find_bridge(node);
>> + of_node_put(node);
>> + if (!priv->output.next_bridge)
>> + return -EPROBE_DEFER;
>> + } else {
>> + struct drm_bridge *bridge;
>> + struct drm_panel *panel;
>> + int ret;
>> +
>> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
>> + &panel, &bridge);
>> + if (ret)
>> + return ret;
>> +
>> + if (panel) {
>> + bridge = drm_panel_bridge_add_typed(panel,
>> + DRM_MODE_CONNECTOR_DSI);
>> + if (IS_ERR(bridge))
>> + return PTR_ERR(bridge);
>> + }
>> +
>> + priv->output.next_bridge = bridge;
>> + priv->output.panel = panel;
>> + }
>> +
>> + return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
>> flags);
>> }
>>
>>
> This patch unfortunately breaks the display output on the Asus TF700T:
>
> [drm:drm_bridge_attach] *ERROR* failed to attach bridge /i2c-mux/i2c@1/dsi@7 to encoder LVDS-59: -517
> tegra-dc 54200000.dc: failed to initialize RGB output: -517
> drm drm: failed to initialize 54200000.dc: -517
> ------------[ cut here ]------------
> WARNING: CPU: 3 PID: 69 at lib/refcount.c:28 tegra_dc_init+0x24/0x5fc
> refcount_t: underflow; use-after-free.
> Modules linked in: elants_i2c panel_simple tc358768 atkbd vivaldi_fmap
> CPU: 3 PID: 69 Comm: kworker/u8:6 Not tainted 6.5.0-rc2-postmarketos-grate #95
> Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
> Workqueue: events_unbound deferred_probe_work_func
> unwind_backtrace from show_stack+0x10/0x14
> show_stack from dump_stack_lvl+0x40/0x4c
> dump_stack_lvl from __warn+0x94/0xc0
> __warn from warn_slowpath_fmt+0x118/0x16c
> warn_slowpath_fmt from tegra_dc_init+0x24/0x5fc
> tegra_dc_init from host1x_device_init+0x84/0x15c
> host1x_device_init from host1x_drm_probe+0xd8/0x3c4
> host1x_drm_probe from really_probe+0xc8/0x2dc
> really_probe from __driver_probe_device+0x88/0x19c
> __driver_probe_device from driver_probe_device+0x30/0x104
> driver_probe_device from __device_attach_driver+0x94/0x108
> __device_attach_driver from bus_for_each_drv+0x80/0xb8
> bus_for_each_drv from __device_attach+0xa0/0x190
> __device_attach from bus_probe_device+0x88/0x8c
> bus_probe_device from deferred_probe_work_func+0x78/0xa4
> deferred_probe_work_func from process_one_work+0x208/0x420
> process_one_work from worker_thread+0x54/0x550
> worker_thread from kthread+0xdc/0xf8
> kthread from ret_from_fork+0x14/0x2c
> Exception stack(0xcf9c5fb0 to 0xcf9c5ff8)
> 5fa0: 00000000 00000000 00000000 00000000
> 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> ---[ end trace 0000000000000000 ]---
Hi Maxim,
Can you try the attached patch (on top of the series)? If it helps, I'll
refresh the series with the fix.
Tomi
On 14.08.23 12:04, Tomi Valkeinen wrote:
> On 13/08/2023 20:11, Maxim Schwalm wrote:
>> On 04.08.23 12:44, Tomi Valkeinen wrote:
>>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>>> ---
>>> drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
>>> 1 file changed, 45 insertions(+), 19 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
>>> index ea19de5509ed..a567f136ddc7 100644
>>> --- a/drivers/gpu/drm/bridge/tc358768.c
>>> +++ b/drivers/gpu/drm/bridge/tc358768.c
>>> @@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
>>>
>>> struct tc358768_dsi_output {
>>> struct mipi_dsi_device *dev;
>>> +
>>> + /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
>>> struct drm_panel *panel;
>>> - struct drm_bridge *bridge;
>>> +
>>> + /*
>>> + * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
>>> + * to tc358768, 'next_bridge' contains the bridge the driver created
>>> + * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
>>> + * the next bridge the driver found.
>>> + */
>>> + struct drm_bridge *next_bridge;
>>> };
>>>
>>> struct tc358768_priv {
>>> @@ -391,8 +400,6 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
>>> struct mipi_dsi_device *dev)
>>> {
>>> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
>>> - struct drm_bridge *bridge;
>>> - struct drm_panel *panel;
>>> struct device_node *ep;
>>> int ret;
>>>
>>> @@ -420,21 +427,7 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
>>> return -ENOTSUPP;
>>> }
>>>
>>> - ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
>>> - &bridge);
>>> - if (ret)
>>> - return ret;
>>> -
>>> - if (panel) {
>>> - bridge = drm_panel_bridge_add_typed(panel,
>>> - DRM_MODE_CONNECTOR_DSI);
>>> - if (IS_ERR(bridge))
>>> - return PTR_ERR(bridge);
>>> - }
>>> -
>>> priv->output.dev = dev;
>>> - priv->output.bridge = bridge;
>>> - priv->output.panel = panel;
>>>
>>> priv->dsi_lanes = dev->lanes;
>>> priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
>>> @@ -463,7 +456,7 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
>>>
>>> drm_bridge_remove(&priv->bridge);
>>> if (priv->output.panel)
>>> - drm_panel_bridge_remove(priv->output.bridge);
>>> + drm_panel_bridge_remove(priv->output.next_bridge);
>>>
>>> return 0;
>>> }
>>> @@ -544,7 +537,40 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
>>> return -ENOTSUPP;
>>> }
>>>
>>> - return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
>>> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
>>> + struct device_node *node;
>>> +
>>> + /* Get the next bridge, connected to port@1. */
>>> + node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
>>> + if (!node)
>>> + return -ENODEV;
>>> +
>>> + priv->output.next_bridge = of_drm_find_bridge(node);
>>> + of_node_put(node);
>>> + if (!priv->output.next_bridge)
>>> + return -EPROBE_DEFER;
>>> + } else {
>>> + struct drm_bridge *bridge;
>>> + struct drm_panel *panel;
>>> + int ret;
>>> +
>>> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
>>> + &panel, &bridge);
>>> + if (ret)
>>> + return ret;
>>> +
>>> + if (panel) {
>>> + bridge = drm_panel_bridge_add_typed(panel,
>>> + DRM_MODE_CONNECTOR_DSI);
>>> + if (IS_ERR(bridge))
>>> + return PTR_ERR(bridge);
>>> + }
>>> +
>>> + priv->output.next_bridge = bridge;
>>> + priv->output.panel = panel;
>>> + }
>>> +
>>> + return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
>>> flags);
>>> }
>>>
>>>
>> This patch unfortunately breaks the display output on the Asus TF700T:
>>
>> [drm:drm_bridge_attach] *ERROR* failed to attach bridge /i2c-mux/i2c@1/dsi@7 to encoder LVDS-59: -517
>> tegra-dc 54200000.dc: failed to initialize RGB output: -517
>> drm drm: failed to initialize 54200000.dc: -517
>> ------------[ cut here ]------------
>> WARNING: CPU: 3 PID: 69 at lib/refcount.c:28 tegra_dc_init+0x24/0x5fc
>> refcount_t: underflow; use-after-free.
>> Modules linked in: elants_i2c panel_simple tc358768 atkbd vivaldi_fmap
>> CPU: 3 PID: 69 Comm: kworker/u8:6 Not tainted 6.5.0-rc2-postmarketos-grate #95
>> Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
>> Workqueue: events_unbound deferred_probe_work_func
>> unwind_backtrace from show_stack+0x10/0x14
>> show_stack from dump_stack_lvl+0x40/0x4c
>> dump_stack_lvl from __warn+0x94/0xc0
>> __warn from warn_slowpath_fmt+0x118/0x16c
>> warn_slowpath_fmt from tegra_dc_init+0x24/0x5fc
>> tegra_dc_init from host1x_device_init+0x84/0x15c
>> host1x_device_init from host1x_drm_probe+0xd8/0x3c4
>> host1x_drm_probe from really_probe+0xc8/0x2dc
>> really_probe from __driver_probe_device+0x88/0x19c
>> __driver_probe_device from driver_probe_device+0x30/0x104
>> driver_probe_device from __device_attach_driver+0x94/0x108
>> __device_attach_driver from bus_for_each_drv+0x80/0xb8
>> bus_for_each_drv from __device_attach+0xa0/0x190
>> __device_attach from bus_probe_device+0x88/0x8c
>> bus_probe_device from deferred_probe_work_func+0x78/0xa4
>> deferred_probe_work_func from process_one_work+0x208/0x420
>> process_one_work from worker_thread+0x54/0x550
>> worker_thread from kthread+0xdc/0xf8
>> kthread from ret_from_fork+0x14/0x2c
>> Exception stack(0xcf9c5fb0 to 0xcf9c5ff8)
>> 5fa0: 00000000 00000000 00000000 00000000
>> 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>> 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>> ---[ end trace 0000000000000000 ]---
>
> Hi Maxim,
>
> Can you try the attached patch (on top of the series)? If it helps, I'll
> refresh the series with the fix.
>
Thanks, Tomi! This fixes the issue.
Best regards,
Maxim
Hi Tomi,
> From c13c691bd8826b978325575be9a87f577b83b86b Mon Sep 17 00:00:00 2001
> From: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> Date: Mon, 14 Aug 2023 13:02:23 +0300
> Subject: [PATCH] drm/bridge: tc358768: fix 'Add DRM_BRIDGE_ATTACH_NO_CONNECTOR
> support'
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> ---
> drivers/gpu/drm/bridge/tc358768.c | 56 +++++++++++++------------------
> 1 file changed, 24 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
> index 82ea4d9a814a..9705ce1bd028 100644
> --- a/drivers/gpu/drm/bridge/tc358768.c
> +++ b/drivers/gpu/drm/bridge/tc358768.c
> @@ -455,8 +455,6 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
>
> drm_bridge_remove(&priv->bridge);
> - if (priv->output.panel)
> - drm_panel_bridge_remove(priv->output.next_bridge);
>
> return 0;
> }
> @@ -531,49 +529,42 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
> enum drm_bridge_attach_flags flags)
> {
> struct tc358768_priv *priv = bridge_to_tc358768(bridge);
> + struct drm_bridge *next_bridge;
> + struct drm_panel *panel;
> + int ret;
>
> if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
> dev_err(priv->dev, "needs atomic updates support\n");
> return -ENOTSUPP;
> }
>
> - if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
> - struct device_node *node;
> -
> - /* Get the next bridge, connected to port@1. */
> - node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
> - if (!node)
> - return -ENODEV;
> -
> - priv->output.next_bridge = of_drm_find_bridge(node);
> - of_node_put(node);
> - if (!priv->output.next_bridge)
> - return -EPROBE_DEFER;
> - } else {
> - struct drm_bridge *bridge;
> - struct drm_panel *panel;
> - int ret;
> -
> - ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
> - &panel, &bridge);
> - if (ret)
> - return ret;
> -
> - if (panel) {
> - bridge = drm_panel_bridge_add_typed(panel,
> - DRM_MODE_CONNECTOR_DSI);
> - if (IS_ERR(bridge))
> - return PTR_ERR(bridge);
> - }
> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, -1, &panel,
> + &next_bridge);
I think the right way is to wrap the panel in a bridge,
so something like:
next_bridge = devm_drm_of_get_bridge(dev, priv->dev->of_node, 1, -1)
if (IS_ERR(next_bridge))
return ...
priv->output.next_bridge = next_bridge;
Sam
> + if (ret)
> + return ret;
>
> - priv->output.next_bridge = bridge;
> - priv->output.panel = panel;
> + if (panel) {
> + next_bridge = drm_panel_bridge_add_typed(panel,
> + DRM_MODE_CONNECTOR_DSI);
> + if (IS_ERR(next_bridge))
> + return PTR_ERR(next_bridge);
> }
>
> + priv->output.next_bridge = next_bridge;
> + priv->output.panel = panel;
> +
> return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
> flags);
> }
>
> +void tc358768_bridge_detach(struct drm_bridge *bridge)
> +{
> + struct tc358768_priv *priv = bridge_to_tc358768(bridge);
> +
> + if (priv->output.panel)
> + drm_panel_bridge_remove(priv->output.next_bridge);
> +}
> +
> static enum drm_mode_status
> tc358768_bridge_mode_valid(struct drm_bridge *bridge,
> const struct drm_display_info *info,
> @@ -1156,6 +1147,7 @@ tc358768_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
>
> static const struct drm_bridge_funcs tc358768_bridge_funcs = {
> .attach = tc358768_bridge_attach,
> + .detach = tc358768_bridge_detach,
> .mode_valid = tc358768_bridge_mode_valid,
> .pre_enable = tc358768_bridge_pre_enable,
> .enable = tc358768_bridge_enable,
> --
> 2.34.1
>
Hi Sam,
On 14/08/2023 13:10, Sam Ravnborg wrote:
> Hi Tomi,
>
>> From c13c691bd8826b978325575be9a87f577b83b86b Mon Sep 17 00:00:00 2001
>> From: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> Date: Mon, 14 Aug 2023 13:02:23 +0300
>> Subject: [PATCH] drm/bridge: tc358768: fix 'Add DRM_BRIDGE_ATTACH_NO_CONNECTOR
>> support'
>>
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> ---
>> drivers/gpu/drm/bridge/tc358768.c | 56 +++++++++++++------------------
>> 1 file changed, 24 insertions(+), 32 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
>> index 82ea4d9a814a..9705ce1bd028 100644
>> --- a/drivers/gpu/drm/bridge/tc358768.c
>> +++ b/drivers/gpu/drm/bridge/tc358768.c
>> @@ -455,8 +455,6 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
>> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
>>
>> drm_bridge_remove(&priv->bridge);
>> - if (priv->output.panel)
>> - drm_panel_bridge_remove(priv->output.next_bridge);
>>
>> return 0;
>> }
>> @@ -531,49 +529,42 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
>> enum drm_bridge_attach_flags flags)
>> {
>> struct tc358768_priv *priv = bridge_to_tc358768(bridge);
>> + struct drm_bridge *next_bridge;
>> + struct drm_panel *panel;
>> + int ret;
>>
>> if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
>> dev_err(priv->dev, "needs atomic updates support\n");
>> return -ENOTSUPP;
>> }
>>
>> - if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
>> - struct device_node *node;
>> -
>> - /* Get the next bridge, connected to port@1. */
>> - node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
>> - if (!node)
>> - return -ENODEV;
>> -
>> - priv->output.next_bridge = of_drm_find_bridge(node);
>> - of_node_put(node);
>> - if (!priv->output.next_bridge)
>> - return -EPROBE_DEFER;
>> - } else {
>> - struct drm_bridge *bridge;
>> - struct drm_panel *panel;
>> - int ret;
>> -
>> - ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
>> - &panel, &bridge);
>> - if (ret)
>> - return ret;
>> -
>> - if (panel) {
>> - bridge = drm_panel_bridge_add_typed(panel,
>> - DRM_MODE_CONNECTOR_DSI);
>> - if (IS_ERR(bridge))
>> - return PTR_ERR(bridge);
>> - }
>> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, -1, &panel,
>> + &next_bridge);
>
> I think the right way is to wrap the panel in a bridge,
> so something like:
>
> next_bridge = devm_drm_of_get_bridge(dev, priv->dev->of_node, 1, -1)
>
> if (IS_ERR(next_bridge))
> return ...
> priv->output.next_bridge = next_bridge;
I tried that, but I had trouble with the cleanup side.
In the fixup patch I attached in my reply to Maxim I used
drm_of_find_panel_or_bridge() + drm_panel_bridge_add_typed(), and on
bridge_detach callback I used drm_panel_bridge_remove() (if there is a
panel). This worked for me, but it does feel like a bit too much work
for a driver to do.
Tomi
On Mon, Aug 14, 2023 at 12:10:41PM +0200, Sam Ravnborg wrote:
> > From c13c691bd8826b978325575be9a87f577b83b86b Mon Sep 17 00:00:00 2001
> > From: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> > Date: Mon, 14 Aug 2023 13:02:23 +0300
> > Subject: [PATCH] drm/bridge: tc358768: fix 'Add DRM_BRIDGE_ATTACH_NO_CONNECTOR
> > support'
> >
> > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> > ---
> > drivers/gpu/drm/bridge/tc358768.c | 56 +++++++++++++------------------
> > 1 file changed, 24 insertions(+), 32 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
> > index 82ea4d9a814a..9705ce1bd028 100644
> > --- a/drivers/gpu/drm/bridge/tc358768.c
> > +++ b/drivers/gpu/drm/bridge/tc358768.c
> > @@ -455,8 +455,6 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
> > struct tc358768_priv *priv = dsi_host_to_tc358768(host);
> >
> > drm_bridge_remove(&priv->bridge);
> > - if (priv->output.panel)
> > - drm_panel_bridge_remove(priv->output.next_bridge);
> >
> > return 0;
> > }
> > @@ -531,49 +529,42 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
> > enum drm_bridge_attach_flags flags)
> > {
> > struct tc358768_priv *priv = bridge_to_tc358768(bridge);
> > + struct drm_bridge *next_bridge;
> > + struct drm_panel *panel;
> > + int ret;
> >
> > if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
> > dev_err(priv->dev, "needs atomic updates support\n");
> > return -ENOTSUPP;
> > }
> >
> > - if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
> > - struct device_node *node;
> > -
> > - /* Get the next bridge, connected to port@1. */
> > - node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
> > - if (!node)
> > - return -ENODEV;
> > -
> > - priv->output.next_bridge = of_drm_find_bridge(node);
> > - of_node_put(node);
> > - if (!priv->output.next_bridge)
> > - return -EPROBE_DEFER;
> > - } else {
> > - struct drm_bridge *bridge;
> > - struct drm_panel *panel;
> > - int ret;
> > -
> > - ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
> > - &panel, &bridge);
> > - if (ret)
> > - return ret;
> > -
> > - if (panel) {
> > - bridge = drm_panel_bridge_add_typed(panel,
> > - DRM_MODE_CONNECTOR_DSI);
> > - if (IS_ERR(bridge))
> > - return PTR_ERR(bridge);
> > - }
> > + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, -1, &panel,
> > + &next_bridge);
>
> I think the right way is to wrap the panel in a bridge,
> so something like:
>
> next_bridge = devm_drm_of_get_bridge(dev, priv->dev->of_node, 1, -1)
>
> if (IS_ERR(next_bridge))
> return ...
> priv->output.next_bridge = next_bridge;
Should we at some point bite the bullet and wrap panels in bridges
directly in drm_panel.c ? That would simplify all the consumers.
> > + if (ret)
> > + return ret;
> >
> > - priv->output.next_bridge = bridge;
> > - priv->output.panel = panel;
> > + if (panel) {
> > + next_bridge = drm_panel_bridge_add_typed(panel,
> > + DRM_MODE_CONNECTOR_DSI);
> > + if (IS_ERR(next_bridge))
> > + return PTR_ERR(next_bridge);
> > }
> >
> > + priv->output.next_bridge = next_bridge;
> > + priv->output.panel = panel;
> > +
> > return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
> > flags);
> > }
> >
> > +void tc358768_bridge_detach(struct drm_bridge *bridge)
> > +{
> > + struct tc358768_priv *priv = bridge_to_tc358768(bridge);
> > +
> > + if (priv->output.panel)
> > + drm_panel_bridge_remove(priv->output.next_bridge);
> > +}
> > +
> > static enum drm_mode_status
> > tc358768_bridge_mode_valid(struct drm_bridge *bridge,
> > const struct drm_display_info *info,
> > @@ -1156,6 +1147,7 @@ tc358768_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
> >
> > static const struct drm_bridge_funcs tc358768_bridge_funcs = {
> > .attach = tc358768_bridge_attach,
> > + .detach = tc358768_bridge_detach,
> > .mode_valid = tc358768_bridge_mode_valid,
> > .pre_enable = tc358768_bridge_pre_enable,
> > .enable = tc358768_bridge_enable,
--
Regards,
Laurent Pinchart
On 13/08/2023 20:11, Maxim Schwalm wrote:
> On 04.08.23 12:44, Tomi Valkeinen wrote:
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> ---
>> drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
>> 1 file changed, 45 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
>> index ea19de5509ed..a567f136ddc7 100644
>> --- a/drivers/gpu/drm/bridge/tc358768.c
>> +++ b/drivers/gpu/drm/bridge/tc358768.c
>> @@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
>>
>> struct tc358768_dsi_output {
>> struct mipi_dsi_device *dev;
>> +
>> + /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
>> struct drm_panel *panel;
>> - struct drm_bridge *bridge;
>> +
>> + /*
>> + * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
>> + * to tc358768, 'next_bridge' contains the bridge the driver created
>> + * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
>> + * the next bridge the driver found.
>> + */
>> + struct drm_bridge *next_bridge;
>> };
>>
>> struct tc358768_priv {
>> @@ -391,8 +400,6 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
>> struct mipi_dsi_device *dev)
>> {
>> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
>> - struct drm_bridge *bridge;
>> - struct drm_panel *panel;
>> struct device_node *ep;
>> int ret;
>>
>> @@ -420,21 +427,7 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
>> return -ENOTSUPP;
>> }
>>
>> - ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
>> - &bridge);
>> - if (ret)
>> - return ret;
>> -
>> - if (panel) {
>> - bridge = drm_panel_bridge_add_typed(panel,
>> - DRM_MODE_CONNECTOR_DSI);
>> - if (IS_ERR(bridge))
>> - return PTR_ERR(bridge);
>> - }
>> -
>> priv->output.dev = dev;
>> - priv->output.bridge = bridge;
>> - priv->output.panel = panel;
>>
>> priv->dsi_lanes = dev->lanes;
>> priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
>> @@ -463,7 +456,7 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
>>
>> drm_bridge_remove(&priv->bridge);
>> if (priv->output.panel)
>> - drm_panel_bridge_remove(priv->output.bridge);
>> + drm_panel_bridge_remove(priv->output.next_bridge);
>>
>> return 0;
>> }
>> @@ -544,7 +537,40 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
>> return -ENOTSUPP;
>> }
>>
>> - return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
>> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
>> + struct device_node *node;
>> +
>> + /* Get the next bridge, connected to port@1. */
>> + node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
>> + if (!node)
>> + return -ENODEV;
>> +
>> + priv->output.next_bridge = of_drm_find_bridge(node);
>> + of_node_put(node);
>> + if (!priv->output.next_bridge)
>> + return -EPROBE_DEFER;
>> + } else {
>> + struct drm_bridge *bridge;
>> + struct drm_panel *panel;
>> + int ret;
>> +
>> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
>> + &panel, &bridge);
>> + if (ret)
>> + return ret;
>> +
>> + if (panel) {
>> + bridge = drm_panel_bridge_add_typed(panel,
>> + DRM_MODE_CONNECTOR_DSI);
>> + if (IS_ERR(bridge))
>> + return PTR_ERR(bridge);
>> + }
>> +
>> + priv->output.next_bridge = bridge;
>> + priv->output.panel = panel;
>> + }
>> +
>> + return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
>> flags);
>> }
>>
>>
> This patch unfortunately breaks the display output on the Asus TF700T:
>
> [drm:drm_bridge_attach] *ERROR* failed to attach bridge /i2c-mux/i2c@1/dsi@7 to encoder LVDS-59: -517
> tegra-dc 54200000.dc: failed to initialize RGB output: -517
> drm drm: failed to initialize 54200000.dc: -517
> ------------[ cut here ]------------
> WARNING: CPU: 3 PID: 69 at lib/refcount.c:28 tegra_dc_init+0x24/0x5fc
> refcount_t: underflow; use-after-free.
> Modules linked in: elants_i2c panel_simple tc358768 atkbd vivaldi_fmap
> CPU: 3 PID: 69 Comm: kworker/u8:6 Not tainted 6.5.0-rc2-postmarketos-grate #95
> Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
> Workqueue: events_unbound deferred_probe_work_func
> unwind_backtrace from show_stack+0x10/0x14
> show_stack from dump_stack_lvl+0x40/0x4c
> dump_stack_lvl from __warn+0x94/0xc0
> __warn from warn_slowpath_fmt+0x118/0x16c
> warn_slowpath_fmt from tegra_dc_init+0x24/0x5fc
> tegra_dc_init from host1x_device_init+0x84/0x15c
> host1x_device_init from host1x_drm_probe+0xd8/0x3c4
> host1x_drm_probe from really_probe+0xc8/0x2dc
> really_probe from __driver_probe_device+0x88/0x19c
> __driver_probe_device from driver_probe_device+0x30/0x104
> driver_probe_device from __device_attach_driver+0x94/0x108
> __device_attach_driver from bus_for_each_drv+0x80/0xb8
> bus_for_each_drv from __device_attach+0xa0/0x190
> __device_attach from bus_probe_device+0x88/0x8c
> bus_probe_device from deferred_probe_work_func+0x78/0xa4
> deferred_probe_work_func from process_one_work+0x208/0x420
> process_one_work from worker_thread+0x54/0x550
> worker_thread from kthread+0xdc/0xf8
> kthread from ret_from_fork+0x14/0x2c
> Exception stack(0xcf9c5fb0 to 0xcf9c5ff8)
> 5fa0: 00000000 00000000 00000000 00000000
> 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> ---[ end trace 0000000000000000 ]---
Sounds like the Tegra driver has issues cleaning up after getting a
EPROBE_DEFER.
The tc358768 driver might have an issue with a setup where a panel is
directly attached to it. I don't have such a setup, but maybe I can fake
it just to see if the probing goes ok.
Tomi
On 04/08/2023 13:44, Tomi Valkeinen wrote:
I would rather have a commit message than a blank one.
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> ---
> drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
> 1 file changed, 45 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
> index ea19de5509ed..a567f136ddc7 100644
> --- a/drivers/gpu/drm/bridge/tc358768.c
> +++ b/drivers/gpu/drm/bridge/tc358768.c
> @@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
>
> struct tc358768_dsi_output {
> struct mipi_dsi_device *dev;
> +
> + /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
> struct drm_panel *panel;
> - struct drm_bridge *bridge;
> +
> + /*
> + * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
> + * to tc358768, 'next_bridge' contains the bridge the driver created
> + * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
> + * the next bridge the driver found.
> + */
> + struct drm_bridge *next_bridge;
why it is better to call it next_bridge than just bridge? Is there a
prev_bridge also?
> };
>
> struct tc358768_priv {
> @@ -391,8 +400,6 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
> struct mipi_dsi_device *dev)
> {
> struct tc358768_priv *priv = dsi_host_to_tc358768(host);
> - struct drm_bridge *bridge;
> - struct drm_panel *panel;
> struct device_node *ep;
> int ret;
>
> @@ -420,21 +427,7 @@ static int tc358768_dsi_host_attach(struct mipi_dsi_host *host,
> return -ENOTSUPP;
> }
>
> - ret = drm_of_find_panel_or_bridge(host->dev->of_node, 1, 0, &panel,
> - &bridge);
> - if (ret)
> - return ret;
> -
> - if (panel) {
> - bridge = drm_panel_bridge_add_typed(panel,
> - DRM_MODE_CONNECTOR_DSI);
> - if (IS_ERR(bridge))
> - return PTR_ERR(bridge);
> - }
> -
> priv->output.dev = dev;
> - priv->output.bridge = bridge;
> - priv->output.panel = panel;
>
> priv->dsi_lanes = dev->lanes;
> priv->dsi_bpp = mipi_dsi_pixel_format_to_bpp(dev->format);
> @@ -463,7 +456,7 @@ static int tc358768_dsi_host_detach(struct mipi_dsi_host *host,
>
> drm_bridge_remove(&priv->bridge);
> if (priv->output.panel)
> - drm_panel_bridge_remove(priv->output.bridge);
> + drm_panel_bridge_remove(priv->output.next_bridge);
>
> return 0;
> }
> @@ -544,7 +537,40 @@ static int tc358768_bridge_attach(struct drm_bridge *bridge,
> return -ENOTSUPP;
> }
>
> - return drm_bridge_attach(bridge->encoder, priv->output.bridge, bridge,
> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) {
> + struct device_node *node;
> +
> + /* Get the next bridge, connected to port@1. */
> + node = of_graph_get_remote_node(priv->dev->of_node, 1, -1);
> + if (!node)
> + return -ENODEV;
> +
> + priv->output.next_bridge = of_drm_find_bridge(node);
> + of_node_put(node);
> + if (!priv->output.next_bridge)
> + return -EPROBE_DEFER;
> + } else {
> + struct drm_bridge *bridge;
> + struct drm_panel *panel;
> + int ret;
> +
> + ret = drm_of_find_panel_or_bridge(priv->dev->of_node, 1, 0,
> + &panel, &bridge);
> + if (ret)
> + return ret;
> +
> + if (panel) {
> + bridge = drm_panel_bridge_add_typed(panel,
> + DRM_MODE_CONNECTOR_DSI);
> + if (IS_ERR(bridge))
> + return PTR_ERR(bridge);
> + }
> +
> + priv->output.next_bridge = bridge;
> + priv->output.panel = panel;
> + }
> +
> + return drm_bridge_attach(bridge->encoder, priv->output.next_bridge, bridge,
> flags);
> }
>
>
--
Péter
On 11/08/2023 19:44, Péter Ujfalusi wrote:
>
>
> On 04/08/2023 13:44, Tomi Valkeinen wrote:
>
> I would rather have a commit message than a blank one.
Oops...
>> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>> ---
>> drivers/gpu/drm/bridge/tc358768.c | 64 +++++++++++++++++++++++++++------------
>> 1 file changed, 45 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/tc358768.c b/drivers/gpu/drm/bridge/tc358768.c
>> index ea19de5509ed..a567f136ddc7 100644
>> --- a/drivers/gpu/drm/bridge/tc358768.c
>> +++ b/drivers/gpu/drm/bridge/tc358768.c
>> @@ -131,8 +131,17 @@ static const char * const tc358768_supplies[] = {
>>
>> struct tc358768_dsi_output {
>> struct mipi_dsi_device *dev;
>> +
>> + /* Legacy field if DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used */
>> struct drm_panel *panel;
>> - struct drm_bridge *bridge;
>> +
>> + /*
>> + * If DRM_BRIDGE_ATTACH_NO_CONNECTOR is not used and a panel is attached
>> + * to tc358768, 'next_bridge' contains the bridge the driver created
>> + * with drm_panel_bridge_add_typed(). Otherwise 'next_bridge' contains
>> + * the next bridge the driver found.
>> + */
>> + struct drm_bridge *next_bridge;
>
> why it is better to call it next_bridge than just bridge? Is there a
> prev_bridge also?
There is, prev bridge would be the bridge behind tc358768 in the chain.
Bridge is tc358768. Next bridge is the following one.
Here, it's in the tc358768_dsi_output struct, so bridge is perhaps ok. I
just wanted to be extra clear here, as I think it's often called
next_bridge in other drivers.
Tomi
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