[PATCH v3 12/13] platform/x86: intel_cht_int33fe: Link with external dependencies using fwnodes

Heikki Krogerus
2019-04-12T13:42:06Z

Supplying also external devices - the DisplayPort connector
and the USB role switch - software fwnodes. After this the
driver has access to all the components tied to the USB
Type-C connector and can start creating software node
references to actually associate them with the USB Type-C
connector device.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
---
drivers/platform/x86/intel_cht_int33fe.c | 93 ++++++++++++++++++++++++
1 file changed, 93 insertions(+)

diff --git a/drivers/platform/x86/intel_cht_int33fe.c b/drivers/platform/x86/intel_cht_int33fe.c
index eff5990322ff..7711667a3454 100644
--- a/drivers/platform/x86/intel_cht_int33fe.c
+++ b/drivers/platform/x86/intel_cht_int33fe.c
@@ -21,6 +21,7 @@
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/module.h>
+#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
@@ -32,6 +33,8 @@ enum {
INT33FE_NODE_FUSB302,
INT33FE_NODE_MAX17047,
INT33FE_NODE_PI3USB30532,
+ INT33FE_NODE_DISPLAYPORT,
+ INT33FE_NODE_ROLE_SWITCH,
INT33FE_NODE_USB_CONNECTOR,
INT33FE_NODE_MAX,
};
@@ -43,6 +46,7 @@ struct cht_int33fe_data {
/* Contain a list-head must be per device */
struct device_connection connections[4];

+ struct fwnode_handle *dp;
struct fwnode_handle *node[INT33FE_NODE_MAX];
};

@@ -143,8 +147,71 @@ static const struct property_entry *props[] = {
[INT33FE_NODE_FUSB302] = fusb302_props,
[INT33FE_NODE_MAX17047] = max17047_props,
[INT33FE_NODE_PI3USB30532] = NULL,
+ [INT33FE_NODE_DISPLAYPORT] = NULL,
+ [INT33FE_NODE_ROLE_SWITCH] = NULL,
};

+static int cht_int33fe_setup_mux(struct cht_int33fe_data *data)
+{
+ struct fwnode_handle *fwnode = data->node[INT33FE_NODE_ROLE_SWITCH];
+ struct pci_dev *pdev;
+ struct device *dev;
+ struct device *p;
+
+ /* First let's find xHCI PCI device */
+ pdev = pci_get_class(PCI_CLASS_SERIAL_USB_XHCI, NULL);
+ if (!pdev || (pdev->vendor != PCI_VENDOR_ID_INTEL))
+ return -ENODEV;
+
+ /* Then the child platform device */
+ p = device_find_child_by_name(&pdev->dev, "intel_xhci_usb_sw");
+ pci_dev_put(pdev);
+ if (!p)
+ return -EPROBE_DEFER;
+
+ /* Finally the mux device */
+ dev = device_find_child_by_name(p, "intel_xhci_usb_sw-role-switch");
+ put_device(p);
+ if (!dev)
+ return -EPROBE_DEFER;
+
+ /* If there already is a node for the mux, using that one. */
+ if (dev->fwnode) {
+ fwnode_handle_get(dev->fwnode);
+ fwnode_remove_software_node(fwnode);
+ data->node[INT33FE_NODE_ROLE_SWITCH] = dev->fwnode;
+ } else {
+ /* The node can be tied to the lifetime of the device. */
+ dev->fwnode = fwnode_handle_get(dev->fwnode);
+ }
+
+ put_device(dev);
+
+ return 0;
+}
+
+static int cht_int33fe_setup_dp(struct cht_int33fe_data *data)
+{
+ struct fwnode_handle *fwnode = data->node[INT33FE_NODE_DISPLAYPORT];
+ struct pci_dev *pdev;
+
+ /* First let's find the GPU PCI device */
+ pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
+ if (!pdev || (pdev->vendor != PCI_VENDOR_ID_INTEL))
+ return -ENODEV;
+
+ /* Then the DP child device node */
+ data->dp = device_get_named_child_node(&pdev->dev, "DD02");
+ pci_dev_put(pdev);
+ if (!data->dp)
+ return -ENODEV;
+
+ fwnode->secondary = ERR_PTR(-ENODEV);
+ data->dp->secondary = fwnode;
+
+ return 0;
+}
+
static void cht_int33fe_remove_nodes(struct cht_int33fe_data *data)
{
int i;
@@ -153,6 +220,12 @@ static void cht_int33fe_remove_nodes(struct cht_int33fe_data *data)
fwnode_remove_software_node(data->node[i]);
data->node[i] = NULL;
}
+
+ if (data->dp) {
+ data->dp->secondary = NULL;
+ fwnode_handle_put(data->dp);
+ data->dp = NULL;
+ }
}

static int cht_int33fe_add_nodes(struct cht_int33fe_data *data)
@@ -179,6 +252,26 @@ static int cht_int33fe_add_nodes(struct cht_int33fe_data *data)
}
data->node[INT33FE_NODE_USB_CONNECTOR] = fwnode;

+ /* The devices that are not created in this driver need extra steps. */
+
+ /*
+ * There is no ACPI device node for the USB role mux, so we need to find
+ * the mux device and assign our node directly to it. That means we
+ * depend on the mux driver. This function will return -PROBE_DEFER
+ * until the mux device is registered.
+ */
+ ret = cht_int33fe_setup_mux(data);
+ if (ret)
+ goto err_remove_nodes;
+
+ /*
+ * The DP connector does have ACPI device node. In this case we can just
+ * find that ACPI node and assing our node as the secondary node to it.
+ */
+ ret = cht_int33fe_setup_dp(data);
+ if (ret)
+ goto err_remove_nodes;
+
return 0;

err_remove_nodes:
--
2.20.1