soc: qcom: pmic_glink: Introduce altmode support
authorBjorn Andersson <bjorn.andersson@linaro.org>
Wed, 1 Feb 2023 04:18:52 +0000 (20:18 -0800)
committerBjorn Andersson <andersson@kernel.org>
Sat, 4 Feb 2023 18:56:16 +0000 (10:56 -0800)
With the PMIC GLINK service, the host OS subscribes to USB-C altmode
messages, which are sent by the firmware to notify the host OS about
state updates and HPD interrupts.

The pmic_glink_altmode driver registers for these notifications and
propagates the notifications as typec_mux, typec_switch and DRM OOB
notifications as necessary to implement DisplayPort altmode support.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
Tested-by: Konrad Dybcio <konrad.dybcio@linaro.org> # SM8350 PDX215
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-MTP & SM8450-HDK
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230201041853.1934355-4-quic_bjorande@quicinc.com
drivers/soc/qcom/Makefile
drivers/soc/qcom/pmic_glink_altmode.c [new file with mode: 0644]

index fbbd1231e55453478055c840b5ded3be90322569..8d62a17863c1c67fa51742e7bfea5c3fb70b2598 100644 (file)
@@ -9,6 +9,7 @@ obj-$(CONFIG_QCOM_MDT_LOADER)   += mdt_loader.o
 obj-$(CONFIG_QCOM_OCMEM)       += ocmem.o
 obj-$(CONFIG_QCOM_PDR_HELPERS) += pdr_interface.o
 obj-$(CONFIG_QCOM_PMIC_GLINK)  += pmic_glink.o
+obj-$(CONFIG_QCOM_PMIC_GLINK)  += pmic_glink_altmode.o
 obj-$(CONFIG_QCOM_QMI_HELPERS) += qmi_helpers.o
 qmi_helpers-y  += qmi_encdec.o qmi_interface.o
 obj-$(CONFIG_QCOM_RMTFS_MEM)   += rmtfs_mem.o
diff --git a/drivers/soc/qcom/pmic_glink_altmode.c b/drivers/soc/qcom/pmic_glink_altmode.c
new file mode 100644 (file)
index 0000000..71f861b
--- /dev/null
@@ -0,0 +1,478 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2019-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2022, Linaro Ltd
+ */
+#include <linux/auxiliary_bus.h>
+#include <linux/bitfield.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/mutex.h>
+#include <linux/property.h>
+#include <linux/soc/qcom/pdr.h>
+#include <drm/drm_bridge.h>
+
+#include <linux/usb/typec_altmode.h>
+#include <linux/usb/typec_dp.h>
+#include <linux/usb/typec_mux.h>
+
+#include <linux/soc/qcom/pmic_glink.h>
+
+#define PMIC_GLINK_MAX_PORTS   2
+
+#define USBC_SC8180X_NOTIFY_IND        0x13
+#define USBC_CMD_WRITE_REQ      0x15
+#define USBC_NOTIFY_IND                0x16
+
+#define ALTMODE_PAN_EN         0x10
+#define ALTMODE_PAN_ACK                0x11
+
+struct usbc_write_req {
+       struct pmic_glink_hdr   hdr;
+       __le32 cmd;
+       __le32 arg;
+       __le32 reserved;
+};
+
+#define NOTIFY_PAYLOAD_SIZE 16
+struct usbc_notify {
+       struct pmic_glink_hdr hdr;
+       char payload[NOTIFY_PAYLOAD_SIZE];
+       u32 reserved;
+};
+
+struct usbc_sc8180x_notify {
+       struct pmic_glink_hdr hdr;
+       __le32 notification;
+       __le32 reserved[2];
+};
+
+enum pmic_glink_altmode_pin_assignment {
+       DPAM_HPD_OUT,
+       DPAM_HPD_A,
+       DPAM_HPD_B,
+       DPAM_HPD_C,
+       DPAM_HPD_D,
+       DPAM_HPD_E,
+       DPAM_HPD_F,
+};
+
+struct pmic_glink_altmode;
+
+#define work_to_altmode_port(w) container_of((w), struct pmic_glink_altmode_port, work)
+
+struct pmic_glink_altmode_port {
+       struct pmic_glink_altmode *altmode;
+       unsigned int index;
+
+       struct typec_switch *typec_switch;
+       struct typec_mux *typec_mux;
+       struct typec_mux_state state;
+       struct typec_altmode dp_alt;
+
+       struct work_struct work;
+
+       struct drm_bridge bridge;
+
+       enum typec_orientation orientation;
+       u16 svid;
+       u8 dp_data;
+       u8 mode;
+       u8 hpd_state;
+       u8 hpd_irq;
+};
+
+#define work_to_altmode(w) container_of((w), struct pmic_glink_altmode, enable_work)
+
+struct pmic_glink_altmode {
+       struct device *dev;
+
+       unsigned int owner_id;
+
+       /* To synchronize WRITE_REQ acks */
+       struct mutex lock;
+
+       struct completion pan_ack;
+       struct pmic_glink_client *client;
+
+       struct work_struct enable_work;
+
+       struct pmic_glink_altmode_port ports[PMIC_GLINK_MAX_PORTS];
+};
+
+static int pmic_glink_altmode_request(struct pmic_glink_altmode *altmode, u32 cmd, u32 arg)
+{
+       struct usbc_write_req req = {};
+       unsigned long left;
+       int ret;
+
+       /*
+        * The USBC_CMD_WRITE_REQ ack doesn't identify the request, so wait for
+        * one ack at a time.
+        */
+       mutex_lock(&altmode->lock);
+
+       req.hdr.owner = cpu_to_le32(altmode->owner_id);
+       req.hdr.type = cpu_to_le32(PMIC_GLINK_REQ_RESP);
+       req.hdr.opcode = cpu_to_le32(USBC_CMD_WRITE_REQ);
+       req.cmd = cpu_to_le32(cmd);
+       req.arg = cpu_to_le32(arg);
+
+       ret = pmic_glink_send(altmode->client, &req, sizeof(req));
+       if (ret) {
+               dev_err(altmode->dev, "failed to send altmode request: %#x (%d)\n", cmd, ret);
+               goto out_unlock;
+       }
+
+       left = wait_for_completion_timeout(&altmode->pan_ack, 5 * HZ);
+       if (!left) {
+               dev_err(altmode->dev, "timeout waiting for altmode request ack for: %#x\n", cmd);
+               ret = -ETIMEDOUT;
+       }
+
+out_unlock:
+       mutex_unlock(&altmode->lock);
+       return ret;
+}
+
+static void pmic_glink_altmode_enable_dp(struct pmic_glink_altmode *altmode,
+                                        struct pmic_glink_altmode_port *port,
+                                        u8 mode, bool hpd_state,
+                                        bool hpd_irq)
+{
+       struct typec_displayport_data dp_data = {};
+       int ret;
+
+       dp_data.status = DP_STATUS_ENABLED;
+       if (hpd_state)
+               dp_data.status |= DP_STATUS_HPD_STATE;
+       if (hpd_irq)
+               dp_data.status |= DP_STATUS_IRQ_HPD;
+       dp_data.conf = DP_CONF_SET_PIN_ASSIGN(mode);
+
+       port->state.alt = &port->dp_alt;
+       port->state.data = &dp_data;
+       port->state.mode = TYPEC_MODAL_STATE(mode);
+
+       ret = typec_mux_set(port->typec_mux, &port->state);
+       if (ret)
+               dev_err(altmode->dev, "failed to switch mux to DP\n");
+}
+
+static void pmic_glink_altmode_enable_usb(struct pmic_glink_altmode *altmode,
+                                         struct pmic_glink_altmode_port *port)
+{
+       int ret;
+
+       port->state.alt = NULL;
+       port->state.data = NULL;
+       port->state.mode = TYPEC_STATE_USB;
+
+       ret = typec_mux_set(port->typec_mux, &port->state);
+       if (ret)
+               dev_err(altmode->dev, "failed to switch mux to USB\n");
+}
+
+static void pmic_glink_altmode_worker(struct work_struct *work)
+{
+       struct pmic_glink_altmode_port *alt_port = work_to_altmode_port(work);
+       struct pmic_glink_altmode *altmode = alt_port->altmode;
+
+       typec_switch_set(alt_port->typec_switch, alt_port->orientation);
+
+       if (alt_port->svid == USB_TYPEC_DP_SID)
+               pmic_glink_altmode_enable_dp(altmode, alt_port, alt_port->mode,
+                                            alt_port->hpd_state, alt_port->hpd_irq);
+       else
+               pmic_glink_altmode_enable_usb(altmode, alt_port);
+
+       if (alt_port->hpd_state)
+               drm_bridge_hpd_notify(&alt_port->bridge, connector_status_connected);
+       else
+               drm_bridge_hpd_notify(&alt_port->bridge, connector_status_disconnected);
+
+       pmic_glink_altmode_request(altmode, ALTMODE_PAN_ACK, alt_port->index);
+};
+
+static enum typec_orientation pmic_glink_altmode_orientation(unsigned int orientation)
+{
+       if (orientation == 0)
+               return TYPEC_ORIENTATION_NORMAL;
+       else if (orientation == 1)
+               return TYPEC_ORIENTATION_REVERSE;
+       else
+               return TYPEC_ORIENTATION_NONE;
+}
+
+#define SC8180X_PORT_MASK              0x000000ff
+#define SC8180X_ORIENTATION_MASK       0x0000ff00
+#define SC8180X_MUX_MASK               0x00ff0000
+#define SC8180X_MODE_MASK              0x3f000000
+#define SC8180X_HPD_STATE_MASK         0x40000000
+#define SC8180X_HPD_IRQ_MASK           0x80000000
+
+static void pmic_glink_altmode_sc8180xp_notify(struct pmic_glink_altmode *altmode,
+                                              const void *data, size_t len)
+{
+       struct pmic_glink_altmode_port *alt_port;
+       const struct usbc_sc8180x_notify *msg;
+       u32 notification;
+       u8 orientation;
+       u8 hpd_state;
+       u8 hpd_irq;
+       u16 svid;
+       u8 port;
+       u8 mode;
+       u8 mux;
+
+       if (len != sizeof(*msg)) {
+               dev_warn(altmode->dev, "invalid length of USBC_NOTIFY indication: %zd\n", len);
+               return;
+       }
+
+       msg = data;
+       notification = le32_to_cpu(msg->notification);
+       port = FIELD_GET(SC8180X_PORT_MASK, notification);
+       orientation = FIELD_GET(SC8180X_ORIENTATION_MASK, notification);
+       mux = FIELD_GET(SC8180X_MUX_MASK, notification);
+       mode = FIELD_GET(SC8180X_MODE_MASK, notification);
+       hpd_state = FIELD_GET(SC8180X_HPD_STATE_MASK, notification);
+       hpd_irq = FIELD_GET(SC8180X_HPD_IRQ_MASK, notification);
+
+       svid = mux == 2 ? USB_TYPEC_DP_SID : 0;
+
+       if (!altmode->ports[port].altmode) {
+               dev_dbg(altmode->dev, "notification on undefined port %d\n", port);
+               return;
+       }
+
+       alt_port = &altmode->ports[port];
+       alt_port->orientation = pmic_glink_altmode_orientation(orientation);
+       alt_port->svid = mux == 2 ? USB_TYPEC_DP_SID : 0;
+       alt_port->mode = mode;
+       alt_port->hpd_state = hpd_state;
+       alt_port->hpd_irq = hpd_irq;
+       schedule_work(&alt_port->work);
+}
+
+#define SC8280XP_DPAM_MASK     0x3f
+#define SC8280XP_HPD_STATE_MASK BIT(6)
+#define SC8280XP_HPD_IRQ_MASK  BIT(7)
+
+static void pmic_glink_altmode_sc8280xp_notify(struct pmic_glink_altmode *altmode,
+                                              u16 svid, const void *data, size_t len)
+{
+       struct pmic_glink_altmode_port *alt_port;
+       const struct usbc_notify *notify;
+       u8 orientation;
+       u8 hpd_state;
+       u8 hpd_irq;
+       u8 mode;
+       u8 port;
+
+       if (len != sizeof(*notify)) {
+               dev_warn(altmode->dev, "invalid length USBC_NOTIFY_IND: %zd\n",
+                        len);
+               return;
+       }
+
+       notify = data;
+
+       port = notify->payload[0];
+       orientation = notify->payload[1];
+       mode = FIELD_GET(SC8280XP_DPAM_MASK, notify->payload[8]) - DPAM_HPD_A;
+       hpd_state = FIELD_GET(SC8280XP_HPD_STATE_MASK, notify->payload[8]);
+       hpd_irq = FIELD_GET(SC8280XP_HPD_IRQ_MASK, notify->payload[8]);
+
+       if (!altmode->ports[port].altmode) {
+               dev_dbg(altmode->dev, "notification on undefined port %d\n", port);
+               return;
+       }
+
+       alt_port = &altmode->ports[port];
+       alt_port->orientation = pmic_glink_altmode_orientation(orientation);
+       alt_port->svid = svid;
+       alt_port->mode = mode;
+       alt_port->hpd_state = hpd_state;
+       alt_port->hpd_irq = hpd_irq;
+       schedule_work(&alt_port->work);
+}
+
+static void pmic_glink_altmode_callback(const void *data, size_t len, void *priv)
+{
+       struct pmic_glink_altmode *altmode = priv;
+       const struct pmic_glink_hdr *hdr = data;
+       u16 opcode;
+       u16 svid;
+
+       opcode = le32_to_cpu(hdr->opcode) & 0xff;
+       svid = le32_to_cpu(hdr->opcode) >> 16;
+
+       switch (opcode) {
+       case USBC_CMD_WRITE_REQ:
+               complete(&altmode->pan_ack);
+               break;
+       case USBC_NOTIFY_IND:
+               pmic_glink_altmode_sc8280xp_notify(altmode, svid, data, len);
+               break;
+       case USBC_SC8180X_NOTIFY_IND:
+               pmic_glink_altmode_sc8180xp_notify(altmode, data, len);
+               break;
+       }
+}
+
+static int pmic_glink_altmode_attach(struct drm_bridge *bridge,
+                                    enum drm_bridge_attach_flags flags)
+{
+       return flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR ? 0 : -EINVAL;
+}
+
+static const struct drm_bridge_funcs pmic_glink_altmode_bridge_funcs = {
+       .attach = pmic_glink_altmode_attach,
+};
+
+static void pmic_glink_altmode_put_mux(void *data)
+{
+       typec_mux_put(data);
+}
+
+static void pmic_glink_altmode_put_switch(void *data)
+{
+       typec_switch_put(data);
+}
+
+static void pmic_glink_altmode_enable_worker(struct work_struct *work)
+{
+       struct pmic_glink_altmode *altmode = work_to_altmode(work);
+       int ret;
+
+       ret = pmic_glink_altmode_request(altmode, ALTMODE_PAN_EN, 0);
+       if (ret)
+               dev_err(altmode->dev, "failed to request altmode notifications\n");
+}
+
+static void pmic_glink_altmode_pdr_notify(void *priv, int state)
+{
+       struct pmic_glink_altmode *altmode = priv;
+
+       if (state == SERVREG_SERVICE_STATE_UP)
+               schedule_work(&altmode->enable_work);
+}
+
+static const struct of_device_id pmic_glink_altmode_of_quirks[] = {
+       { .compatible = "qcom,sc8180x-pmic-glink", .data = (void *)PMIC_GLINK_OWNER_USBC },
+       {}
+};
+
+static int pmic_glink_altmode_probe(struct auxiliary_device *adev,
+                                   const struct auxiliary_device_id *id)
+{
+       struct pmic_glink_altmode_port *alt_port;
+       struct pmic_glink_altmode *altmode;
+       struct typec_altmode_desc mux_desc = {};
+       const struct of_device_id *match;
+       struct fwnode_handle *fwnode;
+       struct device *dev = &adev->dev;
+       u32 port;
+       int ret;
+
+       altmode = devm_kzalloc(dev, sizeof(*altmode), GFP_KERNEL);
+       if (!altmode)
+               return -ENOMEM;
+
+       altmode->dev = dev;
+
+       match = of_match_device(pmic_glink_altmode_of_quirks, dev->parent);
+       if (match)
+               altmode->owner_id = (unsigned long)match->data;
+       else
+               altmode->owner_id = PMIC_GLINK_OWNER_USBC_PAN;
+
+       INIT_WORK(&altmode->enable_work, pmic_glink_altmode_enable_worker);
+       init_completion(&altmode->pan_ack);
+       mutex_init(&altmode->lock);
+
+       device_for_each_child_node(dev, fwnode) {
+               ret = fwnode_property_read_u32(fwnode, "reg", &port);
+               if (ret < 0) {
+                       dev_err(dev, "missing reg property of %pOFn\n", fwnode);
+                       return ret;
+               }
+
+               if (port >= ARRAY_SIZE(altmode->ports)) {
+                       dev_warn(dev, "invalid connector number, ignoring\n");
+                       continue;
+               }
+
+               if (altmode->ports[port].altmode) {
+                       dev_err(dev, "multiple connector definition for port %u\n", port);
+                       return -EINVAL;
+               }
+
+               alt_port = &altmode->ports[port];
+               alt_port->altmode = altmode;
+               alt_port->index = port;
+               INIT_WORK(&alt_port->work, pmic_glink_altmode_worker);
+
+               alt_port->bridge.funcs = &pmic_glink_altmode_bridge_funcs;
+               alt_port->bridge.of_node = to_of_node(fwnode);
+               alt_port->bridge.ops = DRM_BRIDGE_OP_HPD;
+               alt_port->bridge.type = DRM_MODE_CONNECTOR_USB;
+
+               ret = devm_drm_bridge_add(dev, &alt_port->bridge);
+               if (ret)
+                       return ret;
+
+               alt_port->dp_alt.svid = USB_TYPEC_DP_SID;
+               alt_port->dp_alt.mode = USB_TYPEC_DP_MODE;
+               alt_port->dp_alt.active = 1;
+
+               mux_desc.svid = USB_TYPEC_DP_SID;
+               mux_desc.mode = USB_TYPEC_DP_MODE;
+               alt_port->typec_mux = fwnode_typec_mux_get(fwnode, &mux_desc);
+               if (IS_ERR(alt_port->typec_mux))
+                       return dev_err_probe(dev, PTR_ERR(alt_port->typec_mux),
+                                            "failed to acquire mode-switch for port: %d\n",
+                                            port);
+
+               ret = devm_add_action_or_reset(dev, pmic_glink_altmode_put_mux,
+                                              alt_port->typec_mux);
+               if (ret)
+                       return ret;
+
+               alt_port->typec_switch = fwnode_typec_switch_get(fwnode);
+               if (IS_ERR(alt_port->typec_switch))
+                       return dev_err_probe(dev, PTR_ERR(alt_port->typec_switch),
+                                            "failed to acquire orientation-switch for port: %d\n",
+                                            port);
+
+               ret = devm_add_action_or_reset(dev, pmic_glink_altmode_put_switch,
+                                              alt_port->typec_switch);
+               if (ret)
+                       return ret;
+       }
+
+       altmode->client = devm_pmic_glink_register_client(dev,
+                                                         altmode->owner_id,
+                                                         pmic_glink_altmode_callback,
+                                                         pmic_glink_altmode_pdr_notify,
+                                                         altmode);
+       return PTR_ERR_OR_ZERO(altmode->client);
+}
+
+static const struct auxiliary_device_id pmic_glink_altmode_id_table[] = {
+       { .name = "pmic_glink.altmode", },
+       {},
+};
+MODULE_DEVICE_TABLE(auxiliary, pmic_glink_altmode_id_table);
+
+static struct auxiliary_driver pmic_glink_altmode_driver = {
+       .name = "pmic_glink_altmode",
+       .probe = pmic_glink_altmode_probe,
+       .id_table = pmic_glink_altmode_id_table,
+};
+
+module_auxiliary_driver(pmic_glink_altmode_driver);
+
+MODULE_DESCRIPTION("Qualcomm PMIC GLINK Altmode driver");
+MODULE_LICENSE("GPL");