Introduce the UCSI PMIC Glink aux driver that communicates
with the aDSP firmware with the UCSI protocol which handles
the USB-C Port(s) Power Delivery.
The UCSI messaging is necessary on newer Qualcomm SoCs to
provide USB role switch and altmode notifications.
Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
---
drivers/usb/typec/ucsi/Kconfig | 10 ++
drivers/usb/typec/ucsi/Makefile | 1 +
drivers/usb/typec/ucsi/ucsi_glink.c | 320 ++++++++++++++++++++++++++++++++++++
3 files changed, 331 insertions(+)
diff --git a/drivers/usb/typec/ucsi/Kconfig b/drivers/usb/typec/ucsi/Kconfig
index 8f9c4b9f31f7..b3bb0191987e 100644
--- a/drivers/usb/typec/ucsi/Kconfig
+++ b/drivers/usb/typec/ucsi/Kconfig
@@ -58,4 +58,14 @@ config UCSI_STM32G0
To compile the driver as a module, choose M here: the module will be
called ucsi_stm32g0.
+config UCSI_PMIC_GLINK
+ tristate "UCSI Qualcomm PMIC GLINK Interface Driver"
+ depends on QCOM_PMIC_GLINK
+ help
+ This driver enables UCSI support on platforms that expose UCSI
+ interface as PMIC GLINK device.
+
+ To compile the driver as a module, choose M here: the module will be
+ called ucsi_glink.
+
endif
diff --git a/drivers/usb/typec/ucsi/Makefile b/drivers/usb/typec/ucsi/Makefile
index 480d533d762f..77f09e136956 100644
--- a/drivers/usb/typec/ucsi/Makefile
+++ b/drivers/usb/typec/ucsi/Makefile
@@ -18,3 +18,4 @@ endif
obj-$(CONFIG_UCSI_ACPI) += ucsi_acpi.o
obj-$(CONFIG_UCSI_CCG) += ucsi_ccg.o
obj-$(CONFIG_UCSI_STM32G0) += ucsi_stm32g0.o
+obj-$(CONFIG_UCSI_PMIC_GLINK) += ucsi_glink.o
diff --git a/drivers/usb/typec/ucsi/ucsi_glink.c b/drivers/usb/typec/ucsi/ucsi_glink.c
new file mode 100644
index 000000000000..d916e5d59e03
--- /dev/null
+++ b/drivers/usb/typec/ucsi/ucsi_glink.c
@@ -0,0 +1,320 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2019-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2023, Linaro Ltd
+ */
+#include <linux/auxiliary_bus.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 <linux/soc/qcom/pmic_glink.h>
+#include "ucsi.h"
+
+#define UCSI_BUF_SIZE 48
+
+#define MSG_TYPE_REQ_RESP 1
+#define UCSI_BUF_SIZE 48
+
+#define UC_NOTIFY_RECEIVER_UCSI 0x0
+#define UC_UCSI_READ_BUF_REQ 0x11
+#define UC_UCSI_WRITE_BUF_REQ 0x12
+#define UC_UCSI_USBC_NOTIFY_IND 0x13
+
+struct ucsi_read_buf_req_msg {
+ struct pmic_glink_hdr hdr;
+};
+
+struct ucsi_read_buf_resp_msg {
+ struct pmic_glink_hdr hdr;
+ u8 buf[UCSI_BUF_SIZE];
+ u32 ret_code;
+};
+
+struct ucsi_write_buf_req_msg {
+ struct pmic_glink_hdr hdr;
+ u8 buf[UCSI_BUF_SIZE];
+ u32 reserved;
+};
+
+struct ucsi_write_buf_resp_msg {
+ struct pmic_glink_hdr hdr;
+ u32 ret_code;
+};
+
+struct ucsi_notify_ind_msg {
+ struct pmic_glink_hdr hdr;
+ u32 notification;
+ u32 receiver;
+ u32 reserved;
+};
+
+struct pmic_glink_ucsi {
+ struct device *dev;
+
+ struct pmic_glink_client *client;
+
+ struct ucsi *ucsi;
+ struct completion read_ack;
+ struct completion write_ack;
+ struct completion sync_ack;
+ bool sync_pending;
+ struct mutex lock; /* protects concurrent access to PMIC Glink interface */
+
+ int sync_val;
+
+ struct work_struct notify_work;
+ struct work_struct register_work;
+
+ u8 read_buf[UCSI_BUF_SIZE];
+};
+
+static int pmic_glink_ucsi_read(struct ucsi *__ucsi, unsigned int offset,
+ void *val, size_t val_len)
+{
+ struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(__ucsi);
+ struct ucsi_read_buf_req_msg req = {};
+ unsigned long left;
+ int ret;
+
+ req.hdr.owner = PMIC_GLINK_OWNER_USBC;
+ req.hdr.type = MSG_TYPE_REQ_RESP;
+ req.hdr.opcode = UC_UCSI_READ_BUF_REQ;
+
+ mutex_lock(&ucsi->lock);
+ memset(ucsi->read_buf, 0, sizeof(ucsi->read_buf));
+ reinit_completion(&ucsi->read_ack);
+
+ ret = pmic_glink_send(ucsi->client, &req, sizeof(req));
+ if (ret < 0) {
+ dev_err(ucsi->dev, "failed to send UCSI read request: %d\n", ret);
+ goto out_unlock;
+ }
+
+ left = wait_for_completion_timeout(&ucsi->read_ack, 5 * HZ);
+ if (!left) {
+ dev_err(ucsi->dev, "timeout waiting for UCSI read response\n");
+ ret = -ETIMEDOUT;
+ goto out_unlock;
+ }
+
+ memcpy(val, &ucsi->read_buf[offset], val_len);
+ ret = 0;
+
+out_unlock:
+ mutex_unlock(&ucsi->lock);
+
+ return ret;
+}
+
+static int pmic_glink_ucsi_locked_write(struct pmic_glink_ucsi *ucsi, unsigned int offset,
+ const void *val, size_t val_len)
+{
+ struct ucsi_write_buf_req_msg req = {};
+ unsigned long left;
+ int ret;
+
+ req.hdr.owner = PMIC_GLINK_OWNER_USBC;
+ req.hdr.type = MSG_TYPE_REQ_RESP;
+ req.hdr.opcode = UC_UCSI_WRITE_BUF_REQ;
+ memcpy(&req.buf[offset], val, val_len);
+
+ reinit_completion(&ucsi->write_ack);
+
+ ret = pmic_glink_send(ucsi->client, &req, sizeof(req));
+ if (ret < 0) {
+ dev_err(ucsi->dev, "failed to send UCSI write request: %d\n", ret);
+ return ret;
+ }
+
+ left = wait_for_completion_timeout(&ucsi->write_ack, 5 * HZ);
+ if (!left) {
+ dev_err(ucsi->dev, "timeout waiting for UCSI write response\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static int pmic_glink_ucsi_async_write(struct ucsi *__ucsi, unsigned int offset,
+ const void *val, size_t val_len)
+{
+ struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(__ucsi);
+ int ret;
+
+ mutex_lock(&ucsi->lock);
+ ret = pmic_glink_ucsi_locked_write(ucsi, offset, val, val_len);
+ mutex_unlock(&ucsi->lock);
+
+ return ret;
+}
+
+static int pmic_glink_ucsi_sync_write(struct ucsi *__ucsi, unsigned int offset,
+ const void *val, size_t val_len)
+{
+ struct pmic_glink_ucsi *ucsi = ucsi_get_drvdata(__ucsi);
+ unsigned long left;
+ int ret;
+
+ /* TOFIX: Downstream forces recipient to CON when UCSI_GET_ALTERNATE_MODES command */
+
+ mutex_lock(&ucsi->lock);
+ ucsi->sync_val = 0;
+ reinit_completion(&ucsi->sync_ack);
+ ucsi->sync_pending = true;
+ ret = pmic_glink_ucsi_locked_write(ucsi, offset, val, val_len);
+ mutex_unlock(&ucsi->lock);
+
+ left = wait_for_completion_timeout(&ucsi->sync_ack, 5 * HZ);
+ if (!left) {
+ dev_err(ucsi->dev, "timeout waiting for UCSI sync write response\n");
+ ret = -ETIMEDOUT;
+ } else if (ucsi->sync_val) {
+ dev_err(ucsi->dev, "sync write returned: %d\n", ucsi->sync_val);
+ }
+
+ ucsi->sync_pending = false;
+
+ return ret;
+}
+
+static const struct ucsi_operations pmic_glink_ucsi_ops = {
+ .read = pmic_glink_ucsi_read,
+ .sync_write = pmic_glink_ucsi_sync_write,
+ .async_write = pmic_glink_ucsi_async_write
+};
+
+static void pmic_glink_ucsi_read_ack(struct pmic_glink_ucsi *ucsi, const void *data, int len)
+{
+ const struct ucsi_read_buf_resp_msg *resp = data;
+
+ if (resp->ret_code)
+ return;
+
+ memcpy(ucsi->read_buf, resp->buf, UCSI_BUF_SIZE);
+ complete(&ucsi->read_ack);
+}
+
+static void pmic_glink_ucsi_write_ack(struct pmic_glink_ucsi *ucsi, const void *data, int len)
+{
+ const struct ucsi_write_buf_resp_msg *resp = data;
+
+ if (resp->ret_code)
+ return;
+
+ ucsi->sync_val = resp->ret_code;
+ complete(&ucsi->write_ack);
+}
+
+static void pmic_glink_ucsi_notify(struct work_struct *work)
+{
+ struct pmic_glink_ucsi *ucsi = container_of(work, struct pmic_glink_ucsi, notify_work);
+ unsigned int con_num;
+ u32 cci;
+ int ret;
+
+ ret = pmic_glink_ucsi_read(ucsi->ucsi, UCSI_CCI, &cci, sizeof(cci));
+ if (ret) {
+ dev_err(ucsi->dev, "failed to read CCI on notification\n");
+ return;
+ }
+
+ con_num = UCSI_CCI_CONNECTOR(cci);
+ if (con_num)
+ ucsi_connector_change(ucsi->ucsi, con_num);
+
+ if (ucsi->sync_pending && cci & UCSI_CCI_BUSY) {
+ ucsi->sync_val = -EBUSY;
+ complete(&ucsi->sync_ack);
+ } else if (ucsi->sync_pending &&
+ (cci & (UCSI_CCI_ACK_COMPLETE | UCSI_CCI_COMMAND_COMPLETE))) {
+ complete(&ucsi->sync_ack);
+ }
+}
+
+static void pmic_glink_ucsi_register(struct work_struct *work)
+{
+ struct pmic_glink_ucsi *ucsi = container_of(work, struct pmic_glink_ucsi, register_work);
+
+ ucsi_register(ucsi->ucsi);
+}
+
+static void pmic_glink_ucsi_callback(const void *data, size_t len, void *priv)
+{
+ struct pmic_glink_ucsi *ucsi = priv;
+ const struct pmic_glink_hdr *hdr = data;
+
+ switch (hdr->opcode) {
+ case UC_UCSI_READ_BUF_REQ:
+ pmic_glink_ucsi_read_ack(ucsi, data, len);
+ break;
+ case UC_UCSI_WRITE_BUF_REQ:
+ pmic_glink_ucsi_write_ack(ucsi, data, len);
+ break;
+ case UC_UCSI_USBC_NOTIFY_IND:
+ schedule_work(&ucsi->notify_work);
+ break;
+ };
+}
+
+static void pmic_glink_ucsi_pdr_notify(void *priv, int state)
+{
+ struct pmic_glink_ucsi *ucsi = priv;
+
+ if (state == SERVREG_SERVICE_STATE_UP)
+ schedule_work(&ucsi->register_work);
+ else if (state == SERVREG_SERVICE_STATE_DOWN)
+ ucsi_unregister(ucsi->ucsi);
+}
+
+static int pmic_glink_ucsi_probe(struct auxiliary_device *adev,
+ const struct auxiliary_device_id *id)
+{
+ struct pmic_glink_ucsi *ucsi;
+ struct device *dev = &adev->dev;
+
+ ucsi = devm_kzalloc(dev, sizeof(*ucsi), GFP_KERNEL);
+ if (!ucsi)
+ return -ENOMEM;
+
+ ucsi->dev = dev;
+ dev_set_drvdata(dev, ucsi);
+
+ INIT_WORK(&ucsi->notify_work, pmic_glink_ucsi_notify);
+ INIT_WORK(&ucsi->register_work, pmic_glink_ucsi_register);
+ init_completion(&ucsi->read_ack);
+ init_completion(&ucsi->write_ack);
+ init_completion(&ucsi->sync_ack);
+ mutex_init(&ucsi->lock);
+
+ ucsi->ucsi = ucsi_create(dev, &pmic_glink_ucsi_ops);
+ if (IS_ERR(ucsi->ucsi))
+ return PTR_ERR(ucsi->ucsi);
+
+ ucsi_set_drvdata(ucsi->ucsi, ucsi);
+
+ ucsi->client = devm_pmic_glink_register_client(dev,
+ PMIC_GLINK_OWNER_USBC,
+ pmic_glink_ucsi_callback,
+ pmic_glink_ucsi_pdr_notify,
+ ucsi);
+ return PTR_ERR_OR_ZERO(ucsi->client);
+}
+
+static const struct auxiliary_device_id pmic_glink_ucsi_id_table[] = {
+ { .name = "pmic_glink.ucsi", },
+ {},
+};
+MODULE_DEVICE_TABLE(auxiliary, pmic_glink_ucsi_id_table);
+
+static struct auxiliary_driver pmic_glink_ucsi_driver = {
+ .name = "pmic_glink_ucsi",
+ .probe = pmic_glink_ucsi_probe,
+ .id_table = pmic_glink_ucsi_id_table,
+};
+
+module_auxiliary_driver(pmic_glink_ucsi_driver);
+
+MODULE_DESCRIPTION("Qualcomm PMIC GLINK UCSI driver");
+MODULE_LICENSE("GPL");
--
2.34.1
