Register USB Type-C mode switches when the "mode-switch" property and
relevant port are available in Device Tree. Configure the "lane_swap"
state based on the entered alternate mode for a specific Type-C
connector, which ends up updating the lane swap registers of the it6505
chip.
Signed-off-by: Pin-yen Lin <[email protected]>
---
Changes in v6:
- Changed it6505_typec_mux_set callback function to accommodate with
the latest drm-misc patches
- Changed the driver implementation to accommodate with the new binding
- Squashed to a single patch
drivers/gpu/drm/bridge/Kconfig | 1 +
drivers/gpu/drm/bridge/ite-it6505.c | 205 +++++++++++++++++++++++++++-
2 files changed, 202 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index 57946d80b02d..9b1240ef3981 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -87,6 +87,7 @@ config DRM_FSL_LDB
config DRM_ITE_IT6505
tristate "ITE IT6505 DisplayPort bridge"
depends on OF
+ depends on TYPEC || TYPEC=n
select DRM_DISPLAY_DP_HELPER
select DRM_DISPLAY_HDCP_HELPER
select DRM_DISPLAY_HELPER
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 21a9b8422bda..37e2bd8d8d79 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -17,6 +17,8 @@
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/types.h>
+#include <linux/usb/typec_dp.h>
+#include <linux/usb/typec_mux.h>
#include <linux/wait.h>
#include <crypto/hash.h>
@@ -30,6 +32,7 @@
#include <drm/drm_edid.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
+#include <drm/drm_of.h>
#include <sound/hdmi-codec.h>
@@ -402,6 +405,12 @@ struct debugfs_entries {
const struct file_operations *fops;
};
+struct it6505_port_data {
+ bool dp_connected;
+ struct typec_mux_dev *typec_mux;
+ struct it6505 *it6505;
+};
+
struct it6505 {
struct drm_dp_aux aux;
struct drm_bridge bridge;
@@ -454,6 +463,8 @@ struct it6505 {
struct delayed_work delayed_audio;
struct it6505_audio_data audio;
struct dentry *debugfs;
+ int num_typec_switches;
+ struct it6505_port_data *typec_ports;
/* it6505 driver hold option */
bool enable_drv_hold;
@@ -3265,13 +3276,185 @@ static void it6505_shutdown(struct i2c_client *client)
it6505_lane_off(it6505);
}
+static void it6505_typec_ports_update(struct it6505 *it6505)
+{
+ usleep_range(3000, 4000);
+
+ if (it6505->typec_ports[0].dp_connected && it6505->typec_ports[1].dp_connected)
+ /* Both ports available, do nothing to retain the current one. */
+ return;
+ else if (it6505->typec_ports[0].dp_connected)
+ it6505->lane_swap = false;
+ else if (it6505->typec_ports[1].dp_connected)
+ it6505->lane_swap = true;
+
+ usleep_range(3000, 4000);
+}
+
+static int it6505_typec_mux_set(struct typec_mux_dev *mux,
+ struct typec_mux_state *state)
+{
+ struct it6505_port_data *data = typec_mux_get_drvdata(mux);
+ struct it6505 *it6505 = data->it6505;
+ struct device *dev = &it6505->client->dev;
+ bool old_dp_connected, new_dp_connected;
+
+ if (it6505->num_typec_switches == 1)
+ return 0;
+
+ mutex_lock(&it6505->extcon_lock);
+
+ old_dp_connected = it6505->typec_ports[0].dp_connected ||
+ it6505->typec_ports[1].dp_connected;
+
+ data->dp_connected = (state->alt && state->alt->svid == USB_TYPEC_DP_SID &&
+ state->alt->mode == USB_TYPEC_DP_MODE);
+
+ dev_dbg(dev, "mux_set dp_connected: c0=%d, c1=%d\n",
+ it6505->typec_ports[0].dp_connected, it6505->typec_ports[1].dp_connected);
+
+ new_dp_connected = it6505->typec_ports[0].dp_connected ||
+ it6505->typec_ports[1].dp_connected;
+
+ if (it6505->enable_drv_hold) {
+ dev_dbg(dev, "enable driver hold\n");
+ goto unlock;
+ }
+
+ it6505_typec_ports_update(it6505);
+
+ if (!old_dp_connected && new_dp_connected) {
+ int ret = pm_runtime_get_sync(dev);
+
+ /*
+ * On system resume, mux_set can be triggered before
+ * pm_runtime_force_resume re-enables runtime power management.
+ * Handling the error here to make sure the bridge is powered on.
+ */
+ if (ret < 0)
+ it6505_poweron(it6505);
+
+ complete_all(&it6505->extcon_completion);
+ }
+
+ if (old_dp_connected && !new_dp_connected) {
+ reinit_completion(&it6505->extcon_completion);
+ pm_runtime_put_sync(dev);
+ if (it6505->bridge.dev)
+ drm_helper_hpd_irq_event(it6505->bridge.dev);
+ memset(it6505->dpcd, 0, sizeof(it6505->dpcd));
+ }
+
+unlock:
+ mutex_unlock(&it6505->extcon_lock);
+ return 0;
+}
+
+static int it6505_register_mode_switch(struct device *dev, struct device_node *node,
+ struct it6505 *it6505)
+{
+ struct it6505_port_data *port_data;
+ struct typec_mux_desc mux_desc = {};
+ char name[32];
+ u32 dp_lanes[2];
+ int ret, num_lanes, i, port_num = -1;
+
+ num_lanes = drm_of_get_data_lanes_count(node, 0, 2);
+ if (num_lanes <= 0) {
+ dev_err(dev, "Error on getting data lanes count: %d\n",
+ num_lanes);
+ return num_lanes;
+ }
+
+ ret = of_property_read_u32_array(node, "data-lanes", dp_lanes, num_lanes);
+ if (ret) {
+ dev_err(dev, "Failed to read the data-lanes variable: %d\n",
+ ret);
+ return ret;
+ }
+
+ for (i = 0; i < num_lanes; i++) {
+ if (port_num != -1 && port_num != dp_lanes[i] / 2) {
+ dev_err(dev, "Invalid data lane numbers\n");
+ return -EINVAL;
+ }
+ port_num = dp_lanes[i] / 2;
+ }
+
+ port_data = &it6505->typec_ports[port_num];
+ port_data->it6505 = it6505;
+ mux_desc.fwnode = &node->fwnode;
+ mux_desc.drvdata = port_data;
+ snprintf(name, sizeof(name), "%s-%u", node->name, port_num);
+ mux_desc.name = name;
+ mux_desc.set = it6505_typec_mux_set;
+
+ port_data->typec_mux = typec_mux_register(dev, &mux_desc);
+ if (IS_ERR(port_data->typec_mux)) {
+ ret = PTR_ERR(port_data->typec_mux);
+ dev_err(dev, "Mode switch register for port %d failed: %d\n",
+ port_num, ret);
+ }
+
+ return ret;
+}
+
+static void it6505_unregister_typec_switches(struct it6505 *it6505)
+{
+ int i;
+
+ for (i = 0; i < it6505->num_typec_switches; i++)
+ typec_mux_unregister(it6505->typec_ports[i].typec_mux);
+}
+
+static int it6505_register_typec_switches(struct device *dev, struct it6505 *it6505)
+{
+ struct device_node *port, *sw;
+ int ret = 0;
+
+ port = of_graph_get_port_by_id(dev->of_node, 1);
+
+ for_each_child_of_node(port, sw) {
+ if (of_property_read_bool(sw, "mode-switch"))
+ it6505->num_typec_switches++;
+ }
+
+ if (!it6505->num_typec_switches) {
+ dev_warn(dev, "No Type-C switches node found\n");
+ return ret;
+ }
+
+ it6505->typec_ports = devm_kzalloc(
+ dev, it6505->num_typec_switches * sizeof(struct it6505_port_data),
+ GFP_KERNEL);
+ if (!it6505->typec_ports)
+ return -ENOMEM;
+
+ /* Register switches for each connector. */
+ for_each_child_of_node(port, sw) {
+ if (!of_property_read_bool(sw, "mode-switch"))
+ continue;
+ ret = it6505_register_mode_switch(dev, sw, it6505);
+ if (ret) {
+ dev_err(dev, "Failed to register mode switch: %d\n", ret);
+ of_node_put(sw);
+ break;
+ }
+ }
+
+ if (ret)
+ it6505_unregister_typec_switches(it6505);
+
+ return ret;
+}
+
static int it6505_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct it6505 *it6505;
struct device *dev = &client->dev;
struct extcon_dev *extcon;
- int err, intp_irq;
+ int err, intp_irq, ret;
it6505 = devm_kzalloc(&client->dev, sizeof(*it6505), GFP_KERNEL);
if (!it6505)
@@ -3292,11 +3475,24 @@ static int it6505_i2c_probe(struct i2c_client *client,
if (PTR_ERR(extcon) == -EPROBE_DEFER)
return -EPROBE_DEFER;
if (IS_ERR(extcon)) {
- dev_err(dev, "can not get extcon device!");
- return PTR_ERR(extcon);
+ if (PTR_ERR(extcon) != -ENODEV)
+ dev_warn(dev, "Cannot get extcon device: %ld\n",
+ PTR_ERR(extcon));
+ it6505->extcon = NULL;
+ } else {
+ it6505->extcon = extcon;
}
- it6505->extcon = extcon;
+ ret = it6505_register_typec_switches(dev, it6505);
+ if (ret) {
+ if (ret != -ENODEV)
+ dev_warn(dev, "Didn't register Type-C switches, err: %d\n",
+ ret);
+ if (!it6505->extcon) {
+ dev_err(dev, "Both extcon and typec-switch are not registered.\n");
+ return -EINVAL;
+ }
+ }
it6505->regmap = devm_regmap_init_i2c(client, &it6505_regmap_config);
if (IS_ERR(it6505->regmap)) {
@@ -3367,6 +3563,7 @@ static void it6505_i2c_remove(struct i2c_client *client)
drm_dp_aux_unregister(&it6505->aux);
it6505_debugfs_remove(it6505);
it6505_poweroff(it6505);
+ it6505_unregister_typec_switches(it6505);
}
static const struct i2c_device_id it6505_id[] = {
--
2.38.1.584.g0f3c55d4c2-goog
On Thu, Nov 24, 2022 at 06:20:56PM +0800, Pin-yen Lin wrote:
> Register USB Type-C mode switches when the "mode-switch" property and
> relevant port are available in Device Tree. Configure the "lane_swap"
> state based on the entered alternate mode for a specific Type-C
> connector, which ends up updating the lane swap registers of the it6505
> chip.
...
> config DRM_ITE_IT6505
> tristate "ITE IT6505 DisplayPort bridge"
> depends on OF
> + depends on TYPEC || TYPEC=n
> select DRM_DISPLAY_DP_HELPER
> select DRM_DISPLAY_HDCP_HELPER
> select DRM_DISPLAY_HELPER
Something went wrong with the indentation. Perhaps you need to fix it first.
...
> #include <drm/drm_edid.h>
> #include <drm/drm_print.h>
> #include <drm/drm_probe_helper.h>
> +#include <drm/drm_of.h>
Make it ordered?
...
> +struct it6505_port_data {
> + bool dp_connected;
Perhaps make it last?
> + struct typec_mux_dev *typec_mux;
> + struct it6505 *it6505;
> +};
...
> +static void it6505_typec_ports_update(struct it6505 *it6505)
> +{
> + usleep_range(3000, 4000);
> +
> + if (it6505->typec_ports[0].dp_connected && it6505->typec_ports[1].dp_connected)
> + /* Both ports available, do nothing to retain the current one. */
> + return;
> + else if (it6505->typec_ports[0].dp_connected)
> + it6505->lane_swap = false;
> + else if (it6505->typec_ports[1].dp_connected)
> + it6505->lane_swap = true;
> +
> + usleep_range(3000, 4000);
> +}
As per previous patch comments.
Also, comment out these long sleeps. Why they are needed.
...
> + int ret = pm_runtime_get_sync(dev);
> +
> + /*
> + * On system resume, mux_set can be triggered before
> + * pm_runtime_force_resume re-enables runtime power management.
We refer to the functions as func().
> + * Handling the error here to make sure the bridge is powered on.
> + */
> + if (ret < 0)
> + it6505_poweron(it6505);
This seems needed a bit more of explanation, esp. why you leave PM runtime
reference count bumped up.
...
> + num_lanes = drm_of_get_data_lanes_count(node, 0, 2);
> + if (num_lanes <= 0) {
> + dev_err(dev, "Error on getting data lanes count: %d\n",
> + num_lanes);
> + return num_lanes;
> + }
> +
> + ret = of_property_read_u32_array(node, "data-lanes", dp_lanes, num_lanes);
> + if (ret) {
> + dev_err(dev, "Failed to read the data-lanes variable: %d\n",
> + ret);
> + return ret;
> + }
> +
> + for (i = 0; i < num_lanes; i++) {
> + if (port_num != -1 && port_num != dp_lanes[i] / 2) {
> + dev_err(dev, "Invalid data lane numbers\n");
> + return -EINVAL;
> + }
As per previous patch comments.
> + port_num = dp_lanes[i] / 2;
> + }
The above seems like tons of duplicating code that drivers need to implement.
Can we shrink that burden by adding some library functions?
--
With Best Regards,
Andy Shevchenko
Hi Andy,
Thanks for reviewing the patch.
On Thu, Nov 24, 2022 at 8:23 PM Andy Shevchenko
<[email protected]> wrote:
>
> On Thu, Nov 24, 2022 at 06:20:56PM +0800, Pin-yen Lin wrote:
> > Register USB Type-C mode switches when the "mode-switch" property and
> > relevant port are available in Device Tree. Configure the "lane_swap"
> > state based on the entered alternate mode for a specific Type-C
> > connector, which ends up updating the lane swap registers of the it6505
> > chip.
>
> ...
>
> > config DRM_ITE_IT6505
> > tristate "ITE IT6505 DisplayPort bridge"
> > depends on OF
> > + depends on TYPEC || TYPEC=n
> > select DRM_DISPLAY_DP_HELPER
> > select DRM_DISPLAY_HDCP_HELPER
> > select DRM_DISPLAY_HELPER
>
> Something went wrong with the indentation. Perhaps you need to fix it first.
>
> ...
>
> > #include <drm/drm_edid.h>
> > #include <drm/drm_print.h>
> > #include <drm/drm_probe_helper.h>
> > +#include <drm/drm_of.h>
>
> Make it ordered?
Will fix it in v7.
>
> ...
>
> > +struct it6505_port_data {
>
> > + bool dp_connected;
>
> Perhaps make it last?
Will fix it in v7.
>
> > + struct typec_mux_dev *typec_mux;
> > + struct it6505 *it6505;
> > +};
>
> ...
>
> > +static void it6505_typec_ports_update(struct it6505 *it6505)
> > +{
> > + usleep_range(3000, 4000);
> > +
> > + if (it6505->typec_ports[0].dp_connected && it6505->typec_ports[1].dp_connected)
> > + /* Both ports available, do nothing to retain the current one. */
> > + return;
> > + else if (it6505->typec_ports[0].dp_connected)
> > + it6505->lane_swap = false;
> > + else if (it6505->typec_ports[1].dp_connected)
> > + it6505->lane_swap = true;
> > +
> > + usleep_range(3000, 4000);
> > +}
>
> As per previous patch comments.
Will update it in v7.
>
> Also, comment out these long sleeps. Why they are needed.
Actually, it turns out that these sleeps are not needed. I'll remove it in v7.
>
> ...
>
> > + int ret = pm_runtime_get_sync(dev);
> > +
> > + /*
> > + * On system resume, mux_set can be triggered before
> > + * pm_runtime_force_resume re-enables runtime power management.
>
> We refer to the functions as func().
Will fix this in v7.
>
> > + * Handling the error here to make sure the bridge is powered on.
> > + */
> > + if (ret < 0)
> > + it6505_poweron(it6505);
>
> This seems needed a bit more of explanation, esp. why you leave PM runtime
> reference count bumped up.
pm_runtime_force_suspend() disables runtime PM when the device enters
suspend, and sometime it6505_typec_mux_set() is called before
pm_runtime_force_resume brings runtime PM back. We force power up the
bridge in this case and leave the ref count incremented to make the
future pm_runtime_(get|put)_sync() calls balanced.
I'll include more explanations around this in v7.
>
> ...
>
> > + num_lanes = drm_of_get_data_lanes_count(node, 0, 2);
> > + if (num_lanes <= 0) {
> > + dev_err(dev, "Error on getting data lanes count: %d\n",
> > + num_lanes);
> > + return num_lanes;
> > + }
> > +
> > + ret = of_property_read_u32_array(node, "data-lanes", dp_lanes, num_lanes);
> > + if (ret) {
> > + dev_err(dev, "Failed to read the data-lanes variable: %d\n",
> > + ret);
> > + return ret;
> > + }
> > +
> > + for (i = 0; i < num_lanes; i++) {
> > + if (port_num != -1 && port_num != dp_lanes[i] / 2) {
> > + dev_err(dev, "Invalid data lane numbers\n");
> > + return -EINVAL;
> > + }
>
> As per previous patch comments.
I'll remove this part in v7 and try to figure out how to do similar
checking with schemas.
>
> > + port_num = dp_lanes[i] / 2;
> > + }
>
> The above seems like tons of duplicating code that drivers need to implement.
> Can we shrink that burden by adding some library functions?
Could you advise where this lib file should go, and what the namings
can be? The "port-switching" logic is specific to some of the DP
bridges, and I'm not sure what kinds of naming/structure fit into this
case.
Thanks and regards,
Pin-yen
>
> --
> With Best Regards,
> Andy Shevchenko
>
>