usb: Add support for Intel LJCA device
authorWentong Wu <wentong.wu@intel.com>
Mon, 9 Oct 2023 06:33:22 +0000 (14:33 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 11 Oct 2023 09:33:37 +0000 (11:33 +0200)
Implements the USB part of Intel USB-I2C/GPIO/SPI adapter device
named "La Jolla Cove Adapter" (LJCA).

The communication between the various LJCA module drivers and the
hardware will be muxed/demuxed by this driver. Three modules (
I2C, GPIO, and SPI) are supported currently.

Each sub-module of LJCA device is identified by type field within
the LJCA message header.

The sub-modules of LJCA can use ljca_transfer() to issue a transfer
between host and hardware. And ljca_register_event_cb is exported
to LJCA sub-module drivers for hardware event subscription.

The minimum code in ASL that covers this board is
Scope (\_SB.PCI0.DWC3.RHUB.HS01)
    {
        Device (GPIO)
        {
            Name (_ADR, Zero)
            Name (_STA, 0x0F)
        }

        Device (I2C)
        {
            Name (_ADR, One)
            Name (_STA, 0x0F)
        }

        Device (SPI)
        {
            Name (_ADR, 0x02)
            Name (_STA, 0x0F)
        }
    }

Signed-off-by: Wentong Wu <wentong.wu@intel.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/1696833205-16716-2-git-send-email-wentong.wu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/misc/Kconfig
drivers/usb/misc/Makefile
drivers/usb/misc/usb-ljca.c [new file with mode: 0644]
include/linux/usb/ljca.h [new file with mode: 0644]

index 99b15b77dfd576dace539b7166dd574fe134fcdf..c510af7baa0d6d73377826ea6f975bbe0c25c878 100644 (file)
@@ -165,6 +165,19 @@ config APPLE_MFI_FASTCHARGE
 
          It is safe to say M here.
 
+config USB_LJCA
+       tristate "Intel La Jolla Cove Adapter support"
+       select AUXILIARY_BUS
+       depends on USB && ACPI
+       help
+         This adds support for Intel La Jolla Cove USB-I2C/SPI/GPIO
+         Master Adapter (LJCA). Additional drivers such as I2C_LJCA,
+         GPIO_LJCA and SPI_LJCA must be enabled in order to use the
+         functionality of the device.
+
+         This driver can also be built as a module. If so, the module
+         will be called usb-ljca.
+
 source "drivers/usb/misc/sisusbvga/Kconfig"
 
 config USB_LD
index 1992cc284d8aba91f2229810d6b1d9e3b663ef2e..0bc732bcb162b8b6049ccc3cf706705d2ae1e260 100644 (file)
@@ -11,6 +11,7 @@ obj-$(CONFIG_USB_EMI26)                       += emi26.o
 obj-$(CONFIG_USB_EMI62)                        += emi62.o
 obj-$(CONFIG_USB_EZUSB_FX2)            += ezusb.o
 obj-$(CONFIG_APPLE_MFI_FASTCHARGE)     += apple-mfi-fastcharge.o
+obj-$(CONFIG_USB_LJCA)                 += usb-ljca.o
 obj-$(CONFIG_USB_IDMOUSE)              += idmouse.o
 obj-$(CONFIG_USB_IOWARRIOR)            += iowarrior.o
 obj-$(CONFIG_USB_ISIGHTFW)             += isight_firmware.o
diff --git a/drivers/usb/misc/usb-ljca.c b/drivers/usb/misc/usb-ljca.c
new file mode 100644 (file)
index 0000000..c9decd0
--- /dev/null
@@ -0,0 +1,902 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel La Jolla Cove Adapter USB driver
+ *
+ * Copyright (c) 2023, Intel Corporation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/auxiliary_bus.h>
+#include <linux/dev_printk.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+#include <linux/usb/ljca.h>
+
+#include <asm/unaligned.h>
+
+/* command flags */
+#define LJCA_ACK_FLAG                  BIT(0)
+#define LJCA_RESP_FLAG                 BIT(1)
+#define LJCA_CMPL_FLAG                 BIT(2)
+
+#define LJCA_MAX_PACKET_SIZE           64u
+#define LJCA_MAX_PAYLOAD_SIZE          \
+               (LJCA_MAX_PACKET_SIZE - sizeof(struct ljca_msg))
+
+#define LJCA_WRITE_TIMEOUT_MS          200
+#define LJCA_WRITE_ACK_TIMEOUT_MS      500
+#define LJCA_ENUM_CLIENT_TIMEOUT_MS    20
+
+/* ljca client type */
+enum ljca_client_type {
+       LJCA_CLIENT_MNG = 1,
+       LJCA_CLIENT_GPIO = 3,
+       LJCA_CLIENT_I2C = 4,
+       LJCA_CLIENT_SPI = 5,
+};
+
+/* MNG client commands */
+enum ljca_mng_cmd {
+       LJCA_MNG_RESET = 2,
+       LJCA_MNG_ENUM_GPIO = 4,
+       LJCA_MNG_ENUM_I2C = 5,
+       LJCA_MNG_ENUM_SPI = 8,
+};
+
+/* ljca client acpi _ADR */
+enum ljca_client_acpi_adr {
+       LJCA_GPIO_ACPI_ADR,
+       LJCA_I2C1_ACPI_ADR,
+       LJCA_I2C2_ACPI_ADR,
+       LJCA_SPI1_ACPI_ADR,
+       LJCA_SPI2_ACPI_ADR,
+       LJCA_CLIENT_ACPI_ADR_MAX,
+};
+
+/* ljca cmd message structure */
+struct ljca_msg {
+       u8 type;
+       u8 cmd;
+       u8 flags;
+       u8 len;
+       u8 data[] __counted_by(len);
+} __packed;
+
+struct ljca_i2c_ctr_info {
+       u8 id;
+       u8 capacity;
+       u8 intr_pin;
+} __packed;
+
+struct ljca_i2c_descriptor {
+       u8 num;
+       struct ljca_i2c_ctr_info info[] __counted_by(num);
+} __packed;
+
+struct ljca_spi_ctr_info {
+       u8 id;
+       u8 capacity;
+       u8 intr_pin;
+} __packed;
+
+struct ljca_spi_descriptor {
+       u8 num;
+       struct ljca_spi_ctr_info info[] __counted_by(num);
+} __packed;
+
+struct ljca_bank_descriptor {
+       u8 bank_id;
+       u8 pin_num;
+
+       /* 1 bit for each gpio, 1 means valid */
+       __le32 valid_pins;
+} __packed;
+
+struct ljca_gpio_descriptor {
+       u8 pins_per_bank;
+       u8 bank_num;
+       struct ljca_bank_descriptor bank_desc[] __counted_by(bank_num);
+} __packed;
+
+/**
+ * struct ljca_adapter - represent a ljca adapter
+ *
+ * @intf: the usb interface for this ljca adapter
+ * @usb_dev: the usb device for this ljca adapter
+ * @dev: the specific device info of the usb interface
+ * @rx_pipe: bulk in pipe for receive data from firmware
+ * @tx_pipe: bulk out pipe for send data to firmware
+ * @rx_urb: urb used for the bulk in pipe
+ * @rx_buf: buffer used to receive command response and event
+ * @rx_len: length of rx buffer
+ * @ex_buf: external buffer to save command response
+ * @ex_buf_len: length of external buffer
+ * @actual_length: actual length of data copied to external buffer
+ * @tx_buf: buffer used to download command to firmware
+ * @tx_buf_len: length of tx buffer
+ * @lock: spinlock to protect tx_buf and ex_buf
+ * @cmd_completion: completion object as the command receives ack
+ * @mutex: mutex to avoid command download concurrently
+ * @client_list: client device list
+ * @disconnect: usb disconnect ongoing or not
+ * @reset_id: used to reset firmware
+ */
+struct ljca_adapter {
+       struct usb_interface *intf;
+       struct usb_device *usb_dev;
+       struct device *dev;
+
+       unsigned int rx_pipe;
+       unsigned int tx_pipe;
+
+       struct urb *rx_urb;
+       void *rx_buf;
+       unsigned int rx_len;
+
+       u8 *ex_buf;
+       u8 ex_buf_len;
+       u8 actual_length;
+
+       void *tx_buf;
+       u8 tx_buf_len;
+
+       spinlock_t lock;
+
+       struct completion cmd_completion;
+       struct mutex mutex;
+
+       struct list_head client_list;
+
+       bool disconnect;
+
+       u32 reset_id;
+};
+
+struct ljca_match_ids_walk_data {
+       const struct acpi_device_id *ids;
+       const char *uid;
+       struct acpi_device *adev;
+};
+
+static const struct acpi_device_id ljca_gpio_hids[] = {
+       { "INTC1074" },
+       { "INTC1096" },
+       { "INTC100B" },
+       { "INTC10D1" },
+       {},
+};
+
+static const struct acpi_device_id ljca_i2c_hids[] = {
+       { "INTC1075" },
+       { "INTC1097" },
+       { "INTC100C" },
+       { "INTC10D2" },
+       {},
+};
+
+static const struct acpi_device_id ljca_spi_hids[] = {
+       { "INTC1091" },
+       { "INTC1098" },
+       { "INTC100D" },
+       { "INTC10D3" },
+       {},
+};
+
+static void ljca_handle_event(struct ljca_adapter *adap,
+                             struct ljca_msg *header)
+{
+       struct ljca_client *client;
+
+       list_for_each_entry(client, &adap->client_list, link) {
+               /*
+                * Currently only GPIO register event callback, but
+                * firmware message structure should include id when
+                * multiple same type clients register event callback.
+                */
+               if (client->type == header->type) {
+                       unsigned long flags;
+
+                       spin_lock_irqsave(&client->event_cb_lock, flags);
+                       client->event_cb(client->context, header->cmd,
+                                        header->data, header->len);
+                       spin_unlock_irqrestore(&client->event_cb_lock, flags);
+
+                       break;
+               }
+       }
+}
+
+/* process command ack and received data if available */
+static void ljca_handle_cmd_ack(struct ljca_adapter *adap, struct ljca_msg *header)
+{
+       struct ljca_msg *tx_header = adap->tx_buf;
+       u8 ibuf_len, actual_len = 0;
+       unsigned long flags;
+       u8 *ibuf;
+
+       spin_lock_irqsave(&adap->lock, flags);
+
+       if (tx_header->type != header->type || tx_header->cmd != header->cmd) {
+               spin_unlock_irqrestore(&adap->lock, flags);
+               dev_err(adap->dev, "cmd ack mismatch error\n");
+               return;
+       }
+
+       ibuf_len = adap->ex_buf_len;
+       ibuf = adap->ex_buf;
+
+       if (ibuf && ibuf_len) {
+               actual_len = min(header->len, ibuf_len);
+
+               /* copy received data to external buffer */
+               memcpy(ibuf, header->data, actual_len);
+       }
+       /* update copied data length */
+       adap->actual_length = actual_len;
+
+       spin_unlock_irqrestore(&adap->lock, flags);
+
+       complete(&adap->cmd_completion);
+}
+
+static void ljca_recv(struct urb *urb)
+{
+       struct ljca_msg *header = urb->transfer_buffer;
+       struct ljca_adapter *adap = urb->context;
+       int ret;
+
+       switch (urb->status) {
+       case 0:
+               /* success */
+               break;
+       case -ENOENT:
+               /*
+                * directly complete the possible ongoing transfer
+                * during disconnect
+                */
+               if (adap->disconnect)
+                       complete(&adap->cmd_completion);
+               return;
+       case -ECONNRESET:
+       case -ESHUTDOWN:
+       case -EPIPE:
+               /* rx urb is terminated */
+               dev_dbg(adap->dev, "rx urb terminated with status: %d\n",
+                       urb->status);
+               return;
+       default:
+               dev_dbg(adap->dev, "rx urb error: %d\n", urb->status);
+               goto resubmit;
+       }
+
+       if (header->len + sizeof(*header) != urb->actual_length)
+               goto resubmit;
+
+       if (header->flags & LJCA_ACK_FLAG)
+               ljca_handle_cmd_ack(adap, header);
+       else
+               ljca_handle_event(adap, header);
+
+resubmit:
+       ret = usb_submit_urb(urb, GFP_ATOMIC);
+       if (ret && ret != -EPERM)
+               dev_err(adap->dev, "resubmit rx urb error %d\n", ret);
+}
+
+static int ljca_send(struct ljca_adapter *adap, u8 type, u8 cmd,
+                    const u8 *obuf, u8 obuf_len, u8 *ibuf, u8 ibuf_len,
+                    bool ack, unsigned long timeout)
+{
+       unsigned int msg_len = sizeof(struct ljca_msg) + obuf_len;
+       struct ljca_msg *header = adap->tx_buf;
+       unsigned int transferred;
+       unsigned long flags;
+       int ret;
+
+       if (adap->disconnect)
+               return -ENODEV;
+
+       if (msg_len > adap->tx_buf_len)
+               return -EINVAL;
+
+       mutex_lock(&adap->mutex);
+
+       spin_lock_irqsave(&adap->lock, flags);
+
+       header->type = type;
+       header->cmd = cmd;
+       header->len = obuf_len;
+       if (obuf)
+               memcpy(header->data, obuf, obuf_len);
+
+       header->flags = LJCA_CMPL_FLAG | (ack ? LJCA_ACK_FLAG : 0);
+
+       adap->ex_buf = ibuf;
+       adap->ex_buf_len = ibuf_len;
+       adap->actual_length = 0;
+
+       spin_unlock_irqrestore(&adap->lock, flags);
+
+       reinit_completion(&adap->cmd_completion);
+
+       ret = usb_autopm_get_interface(adap->intf);
+       if (ret < 0)
+               goto out;
+
+       ret = usb_bulk_msg(adap->usb_dev, adap->tx_pipe, header,
+                          msg_len, &transferred, LJCA_WRITE_TIMEOUT_MS);
+
+       usb_autopm_put_interface(adap->intf);
+
+       if (ret < 0)
+               goto out;
+       if (transferred != msg_len) {
+               ret = -EIO;
+               goto out;
+       }
+
+       if (ack) {
+               ret = wait_for_completion_timeout(&adap->cmd_completion,
+                                                 timeout);
+               if (!ret) {
+                       ret = -ETIMEDOUT;
+                       goto out;
+               }
+       }
+       ret = adap->actual_length;
+
+out:
+       spin_lock_irqsave(&adap->lock, flags);
+       adap->ex_buf = NULL;
+       adap->ex_buf_len = 0;
+
+       memset(header, 0, sizeof(*header));
+       spin_unlock_irqrestore(&adap->lock, flags);
+
+       mutex_unlock(&adap->mutex);
+
+       return ret;
+}
+
+int ljca_transfer(struct ljca_client *client, u8 cmd, const u8 *obuf,
+                 u8 obuf_len, u8 *ibuf, u8 ibuf_len)
+{
+       return ljca_send(client->adapter, client->type, cmd,
+                        obuf, obuf_len, ibuf, ibuf_len, true,
+                        LJCA_WRITE_ACK_TIMEOUT_MS);
+}
+EXPORT_SYMBOL_NS_GPL(ljca_transfer, LJCA);
+
+int ljca_transfer_noack(struct ljca_client *client, u8 cmd, const u8 *obuf,
+                       u8 obuf_len)
+{
+       return ljca_send(client->adapter, client->type, cmd, obuf,
+                        obuf_len, NULL, 0, false, LJCA_WRITE_ACK_TIMEOUT_MS);
+}
+EXPORT_SYMBOL_NS_GPL(ljca_transfer_noack, LJCA);
+
+int ljca_register_event_cb(struct ljca_client *client, ljca_event_cb_t event_cb,
+                          void *context)
+{
+       unsigned long flags;
+
+       if (!event_cb)
+               return -EINVAL;
+
+       spin_lock_irqsave(&client->event_cb_lock, flags);
+
+       if (client->event_cb) {
+               spin_unlock_irqrestore(&client->event_cb_lock, flags);
+               return -EALREADY;
+       }
+
+       client->event_cb = event_cb;
+       client->context = context;
+
+       spin_unlock_irqrestore(&client->event_cb_lock, flags);
+
+       return 0;
+}
+EXPORT_SYMBOL_NS_GPL(ljca_register_event_cb, LJCA);
+
+void ljca_unregister_event_cb(struct ljca_client *client)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&client->event_cb_lock, flags);
+
+       client->event_cb = NULL;
+       client->context = NULL;
+
+       spin_unlock_irqrestore(&client->event_cb_lock, flags);
+}
+EXPORT_SYMBOL_NS_GPL(ljca_unregister_event_cb, LJCA);
+
+static int ljca_match_device_ids(struct acpi_device *adev, void *data)
+{
+       struct ljca_match_ids_walk_data *wd = data;
+       const char *uid = acpi_device_uid(adev);
+
+       if (acpi_match_device_ids(adev, wd->ids))
+               return 0;
+
+       if (!wd->uid)
+               goto match;
+
+       if (!uid)
+               /*
+                * Some DSDTs have only one ACPI companion for the two I2C
+                * controllers and they don't set a UID at all (e.g. Dell
+                * Latitude 9420). On these platforms only the first I2C
+                * controller is used, so if a HID match has no UID we use
+                * "0" as the UID and assign ACPI companion to the first
+                * I2C controller.
+                */
+               uid = "0";
+       else
+               uid = strchr(uid, wd->uid[0]);
+
+       if (!uid || strcmp(uid, wd->uid))
+               return 0;
+
+match:
+       wd->adev = adev;
+
+       return 1;
+}
+
+/* bind auxiliary device to acpi device */
+static void ljca_auxdev_acpi_bind(struct ljca_adapter *adap,
+                                 struct auxiliary_device *auxdev,
+                                 u64 adr, u8 id)
+{
+       struct ljca_match_ids_walk_data wd = { 0 };
+       struct acpi_device *parent, *adev;
+       struct device *dev = adap->dev;
+       char uid[4];
+
+       parent = ACPI_COMPANION(dev);
+       if (!parent)
+               return;
+
+       /*
+        * get auxdev ACPI handle from the ACPI device directly
+        * under the parent that matches _ADR.
+        */
+       adev = acpi_find_child_device(parent, adr, false);
+       if (adev) {
+               ACPI_COMPANION_SET(&auxdev->dev, adev);
+               return;
+       }
+
+       /*
+        * _ADR is a grey area in the ACPI specification, some
+        * platforms use _HID to distinguish children devices.
+        */
+       switch (adr) {
+       case LJCA_GPIO_ACPI_ADR:
+               wd.ids = ljca_gpio_hids;
+               break;
+       case LJCA_I2C1_ACPI_ADR:
+       case LJCA_I2C2_ACPI_ADR:
+               snprintf(uid, sizeof(uid), "%d", id);
+               wd.uid = uid;
+               wd.ids = ljca_i2c_hids;
+               break;
+       case LJCA_SPI1_ACPI_ADR:
+       case LJCA_SPI2_ACPI_ADR:
+               wd.ids = ljca_spi_hids;
+               break;
+       default:
+               dev_warn(dev, "unsupported _ADR\n");
+               return;
+       }
+
+       acpi_dev_for_each_child(parent, ljca_match_device_ids, &wd);
+       if (wd.adev) {
+               ACPI_COMPANION_SET(&auxdev->dev, wd.adev);
+               return;
+       }
+
+       parent = ACPI_COMPANION(dev->parent->parent);
+       if (!parent)
+               return;
+
+       acpi_dev_for_each_child(parent, ljca_match_device_ids, &wd);
+       if (wd.adev)
+               ACPI_COMPANION_SET(&auxdev->dev, wd.adev);
+}
+
+static void ljca_auxdev_release(struct device *dev)
+{
+       struct auxiliary_device *auxdev = to_auxiliary_dev(dev);
+
+       kfree(auxdev->dev.platform_data);
+}
+
+static int ljca_new_client_device(struct ljca_adapter *adap, u8 type, u8 id,
+                                 char *name, void *data, u64 adr)
+{
+       struct auxiliary_device *auxdev;
+       struct ljca_client *client;
+       int ret;
+
+       client = kzalloc(sizeof *client, GFP_KERNEL);
+       if (!client)
+               return -ENOMEM;
+
+       client->type = type;
+       client->id = id;
+       client->adapter = adap;
+       spin_lock_init(&client->event_cb_lock);
+
+       auxdev = &client->auxdev;
+       auxdev->name = name;
+       auxdev->id = id;
+
+       auxdev->dev.parent = adap->dev;
+       auxdev->dev.platform_data = data;
+       auxdev->dev.release = ljca_auxdev_release;
+
+       ret = auxiliary_device_init(auxdev);
+       if (ret)
+               goto err_free;
+
+       ljca_auxdev_acpi_bind(adap, auxdev, adr, id);
+
+       ret = auxiliary_device_add(auxdev);
+       if (ret)
+               goto err_uninit;
+
+       list_add_tail(&client->link, &adap->client_list);
+
+       return 0;
+
+err_uninit:
+       auxiliary_device_uninit(auxdev);
+
+err_free:
+       kfree(client);
+
+       return ret;
+}
+
+static int ljca_enumerate_gpio(struct ljca_adapter *adap)
+{
+       u32 valid_pin[LJCA_MAX_GPIO_NUM / BITS_PER_TYPE(u32)];
+       struct ljca_gpio_descriptor *desc;
+       struct ljca_gpio_info *gpio_info;
+       u8 buf[LJCA_MAX_PAYLOAD_SIZE];
+       int ret, gpio_num;
+       unsigned int i;
+
+       ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_ENUM_GPIO, NULL, 0, buf,
+                       sizeof(buf), true, LJCA_ENUM_CLIENT_TIMEOUT_MS);
+       if (ret < 0)
+               return ret;
+
+       /* check firmware response */
+       desc = (struct ljca_gpio_descriptor *)buf;
+       if (ret != struct_size(desc, bank_desc, desc->bank_num))
+               return -EINVAL;
+
+       gpio_num = desc->pins_per_bank * desc->bank_num;
+       if (gpio_num > LJCA_MAX_GPIO_NUM)
+               return -EINVAL;
+
+       /* construct platform data */
+       gpio_info = kzalloc(sizeof *gpio_info, GFP_KERNEL);
+       if (!gpio_info)
+               return -ENOMEM;
+       gpio_info->num = gpio_num;
+
+       for (i = 0; i < desc->bank_num; i++)
+               valid_pin[i] = get_unaligned_le32(&desc->bank_desc[i].valid_pins);
+       bitmap_from_arr32(gpio_info->valid_pin_map, valid_pin, gpio_num);
+
+       ret = ljca_new_client_device(adap, LJCA_CLIENT_GPIO, 0, "ljca-gpio",
+                                    gpio_info, LJCA_GPIO_ACPI_ADR);
+       if (ret)
+               kfree(gpio_info);
+
+       return ret;
+}
+
+static int ljca_enumerate_i2c(struct ljca_adapter *adap)
+{
+       struct ljca_i2c_descriptor *desc;
+       struct ljca_i2c_info *i2c_info;
+       u8 buf[LJCA_MAX_PAYLOAD_SIZE];
+       unsigned int i;
+       int ret;
+
+       ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_ENUM_I2C, NULL, 0, buf,
+                       sizeof(buf), true, LJCA_ENUM_CLIENT_TIMEOUT_MS);
+       if (ret < 0)
+               return ret;
+
+       /* check firmware response */
+       desc = (struct ljca_i2c_descriptor *)buf;
+       if (ret != struct_size(desc, info, desc->num))
+               return -EINVAL;
+
+       for (i = 0; i < desc->num; i++) {
+               /* construct platform data */
+               i2c_info = kzalloc(sizeof *i2c_info, GFP_KERNEL);
+               if (!i2c_info)
+                       return -ENOMEM;
+
+               i2c_info->id = desc->info[i].id;
+               i2c_info->capacity = desc->info[i].capacity;
+               i2c_info->intr_pin = desc->info[i].intr_pin;
+
+               ret = ljca_new_client_device(adap, LJCA_CLIENT_I2C, i,
+                                            "ljca-i2c", i2c_info,
+                                            LJCA_I2C1_ACPI_ADR + i);
+               if (ret) {
+                       kfree(i2c_info);
+                       return ret;
+               }
+       }
+
+       return 0;
+}
+
+static int ljca_enumerate_spi(struct ljca_adapter *adap)
+{
+       struct ljca_spi_descriptor *desc;
+       struct ljca_spi_info *spi_info;
+       u8 buf[LJCA_MAX_PAYLOAD_SIZE];
+       unsigned int i;
+       int ret;
+
+       ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_ENUM_SPI, NULL, 0, buf,
+                       sizeof(buf), true, LJCA_ENUM_CLIENT_TIMEOUT_MS);
+       if (ret < 0)
+               return ret;
+
+       /* check firmware response */
+       desc = (struct ljca_spi_descriptor *)buf;
+       if (ret != struct_size(desc, info, desc->num))
+               return -EINVAL;
+
+       for (i = 0; i < desc->num; i++) {
+               /* construct platform data */
+               spi_info = kzalloc(sizeof *spi_info, GFP_KERNEL);
+               if (!spi_info)
+                       return -ENOMEM;
+
+               spi_info->id = desc->info[i].id;
+               spi_info->capacity = desc->info[i].capacity;
+
+               ret = ljca_new_client_device(adap, LJCA_CLIENT_SPI, i,
+                                            "ljca-spi", spi_info,
+                                            LJCA_SPI1_ACPI_ADR + i);
+               if (ret) {
+                       kfree(spi_info);
+                       return ret;
+               }
+       }
+
+       return 0;
+}
+
+static int ljca_reset_handshake(struct ljca_adapter *adap)
+{
+       __le32 reset_id = cpu_to_le32(adap->reset_id);
+       __le32 reset_id_ret = 0;
+       int ret;
+
+       adap->reset_id++;
+
+       ret = ljca_send(adap, LJCA_CLIENT_MNG, LJCA_MNG_RESET, (u8 *)&reset_id,
+                       sizeof(__le32), (u8 *)&reset_id_ret, sizeof(__le32),
+                       true, LJCA_WRITE_ACK_TIMEOUT_MS);
+       if (ret < 0)
+               return ret;
+
+       if (reset_id_ret != reset_id)
+               return -EINVAL;
+
+       return 0;
+}
+
+static int ljca_enumerate_clients(struct ljca_adapter *adap)
+{
+       struct ljca_client *client, *next;
+       int ret;
+
+       ret = ljca_reset_handshake(adap);
+       if (ret)
+               goto err_kill;
+
+       ret = ljca_enumerate_gpio(adap);
+       if (ret) {
+               dev_err(adap->dev, "enumerate GPIO error\n");
+               goto err_kill;
+       }
+
+       ret = ljca_enumerate_i2c(adap);
+       if (ret) {
+               dev_err(adap->dev, "enumerate I2C error\n");
+               goto err_kill;
+       }
+
+       ret = ljca_enumerate_spi(adap);
+       if (ret) {
+               dev_err(adap->dev, "enumerate SPI error\n");
+               goto err_kill;
+       }
+
+       return 0;
+
+err_kill:
+       adap->disconnect = true;
+
+       usb_kill_urb(adap->rx_urb);
+
+       list_for_each_entry_safe_reverse(client, next, &adap->client_list, link) {
+               auxiliary_device_delete(&client->auxdev);
+               auxiliary_device_uninit(&client->auxdev);
+
+               list_del_init(&client->link);
+               kfree(client);
+       }
+
+       return ret;
+}
+
+static int ljca_probe(struct usb_interface *interface,
+                     const struct usb_device_id *id)
+{
+       struct usb_device *usb_dev = interface_to_usbdev(interface);
+       struct usb_host_interface *alt = interface->cur_altsetting;
+       struct usb_endpoint_descriptor *ep_in, *ep_out;
+       struct device *dev = &interface->dev;
+       struct ljca_adapter *adap;
+       int ret;
+
+       adap = devm_kzalloc(dev, sizeof(*adap), GFP_KERNEL);
+       if (!adap)
+               return -ENOMEM;
+
+       /* separate tx buffer allocation for alignment */
+       adap->tx_buf = devm_kzalloc(dev, LJCA_MAX_PACKET_SIZE, GFP_KERNEL);
+       if (!adap->tx_buf)
+               return -ENOMEM;
+       adap->tx_buf_len = LJCA_MAX_PACKET_SIZE;
+
+       mutex_init(&adap->mutex);
+       spin_lock_init(&adap->lock);
+       init_completion(&adap->cmd_completion);
+       INIT_LIST_HEAD(&adap->client_list);
+
+       adap->intf = usb_get_intf(interface);
+       adap->usb_dev = usb_dev;
+       adap->dev = dev;
+
+       /*
+        * find the first bulk in and out endpoints.
+        * ignore any others.
+        */
+       ret = usb_find_common_endpoints(alt, &ep_in, &ep_out, NULL, NULL);
+       if (ret) {
+               dev_err(dev, "bulk endpoints not found\n");
+               goto err_put;
+       }
+       adap->rx_pipe = usb_rcvbulkpipe(usb_dev, usb_endpoint_num(ep_in));
+       adap->tx_pipe = usb_sndbulkpipe(usb_dev, usb_endpoint_num(ep_out));
+
+       /* setup rx buffer */
+       adap->rx_len = usb_endpoint_maxp(ep_in);
+       adap->rx_buf = devm_kzalloc(dev, adap->rx_len, GFP_KERNEL);
+       if (!adap->rx_buf) {
+               ret = -ENOMEM;
+               goto err_put;
+       }
+
+       /* alloc rx urb */
+       adap->rx_urb = usb_alloc_urb(0, GFP_KERNEL);
+       if (!adap->rx_urb) {
+               ret = -ENOMEM;
+               goto err_put;
+       }
+       usb_fill_bulk_urb(adap->rx_urb, usb_dev, adap->rx_pipe,
+                         adap->rx_buf, adap->rx_len, ljca_recv, adap);
+
+       usb_set_intfdata(interface, adap);
+
+       /* submit rx urb before enumerate clients */
+       ret = usb_submit_urb(adap->rx_urb, GFP_KERNEL);
+       if (ret) {
+               dev_err(dev, "submit rx urb failed: %d\n", ret);
+               goto err_free;
+       }
+
+       ret = ljca_enumerate_clients(adap);
+       if (ret)
+               goto err_free;
+
+       usb_enable_autosuspend(usb_dev);
+
+       return 0;
+
+err_free:
+       usb_free_urb(adap->rx_urb);
+
+err_put:
+       usb_put_intf(adap->intf);
+
+       mutex_destroy(&adap->mutex);
+
+       return ret;
+}
+
+static void ljca_disconnect(struct usb_interface *interface)
+{
+       struct ljca_adapter *adap = usb_get_intfdata(interface);
+       struct ljca_client *client, *next;
+
+       adap->disconnect = true;
+
+       usb_kill_urb(adap->rx_urb);
+
+       list_for_each_entry_safe_reverse(client, next, &adap->client_list, link) {
+               auxiliary_device_delete(&client->auxdev);
+               auxiliary_device_uninit(&client->auxdev);
+
+               list_del_init(&client->link);
+               kfree(client);
+       }
+
+       usb_free_urb(adap->rx_urb);
+
+       usb_put_intf(adap->intf);
+
+       mutex_destroy(&adap->mutex);
+}
+
+static int ljca_suspend(struct usb_interface *interface, pm_message_t message)
+{
+       struct ljca_adapter *adap = usb_get_intfdata(interface);
+
+       usb_kill_urb(adap->rx_urb);
+
+       return 0;
+}
+
+static int ljca_resume(struct usb_interface *interface)
+{
+       struct ljca_adapter *adap = usb_get_intfdata(interface);
+
+       return usb_submit_urb(adap->rx_urb, GFP_KERNEL);
+}
+
+static const struct usb_device_id ljca_table[] = {
+       { USB_DEVICE(0x8086, 0x0b63) },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(usb, ljca_table);
+
+static struct usb_driver ljca_driver = {
+       .name = "ljca",
+       .id_table = ljca_table,
+       .probe = ljca_probe,
+       .disconnect = ljca_disconnect,
+       .suspend = ljca_suspend,
+       .resume = ljca_resume,
+       .supports_autosuspend = 1,
+};
+module_usb_driver(ljca_driver);
+
+MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>");
+MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
+MODULE_AUTHOR("Lixu Zhang <lixu.zhang@intel.com>");
+MODULE_DESCRIPTION("Intel La Jolla Cove Adapter USB driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/usb/ljca.h b/include/linux/usb/ljca.h
new file mode 100644 (file)
index 0000000..47661fe
--- /dev/null
@@ -0,0 +1,145 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023, Intel Corporation. All rights reserved.
+ */
+#ifndef _LINUX_USB_LJCA_H_
+#define _LINUX_USB_LJCA_H_
+
+#include <linux/auxiliary_bus.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#define LJCA_MAX_GPIO_NUM 64
+
+#define auxiliary_dev_to_ljca_client(auxiliary_dev)                    \
+               container_of(auxiliary_dev, struct ljca_client, auxdev)
+
+struct ljca_adapter;
+
+/**
+ * typedef ljca_event_cb_t - event callback function signature
+ *
+ * @context: the execution context of who registered this callback
+ * @cmd: the command from device for this event
+ * @evt_data: the event data payload
+ * @len: the event data payload length
+ *
+ * The callback function is called in interrupt context and the data payload is
+ * only valid during the call. If the user needs later access of the data, it
+ * must copy it.
+ */
+typedef void (*ljca_event_cb_t)(void *context, u8 cmd, const void *evt_data, int len);
+
+/**
+ * struct ljca_client - represent a ljca client device
+ *
+ * @type: ljca client type
+ * @id: ljca client id within same client type
+ * @link: ljca client on the same ljca adapter
+ * @auxdev: auxiliary device object
+ * @adapter: ljca adapter the ljca client sit on
+ * @context: the execution context of the event callback
+ * @event_cb: ljca client driver register this callback to get
+ *     firmware asynchronous rx buffer pending notifications
+ * @event_cb_lock: spinlock to protect event callback
+ */
+struct ljca_client {
+       u8 type;
+       u8 id;
+       struct list_head link;
+       struct auxiliary_device auxdev;
+       struct ljca_adapter *adapter;
+
+       void *context;
+       ljca_event_cb_t event_cb;
+       /* lock to protect event_cb */
+       spinlock_t event_cb_lock;
+};
+
+/**
+ * struct ljca_gpio_info - ljca gpio client device info
+ *
+ * @num: ljca gpio client device pin number
+ * @valid_pin_map: ljca gpio client device valid pin mapping
+ */
+struct ljca_gpio_info {
+       unsigned int num;
+       DECLARE_BITMAP(valid_pin_map, LJCA_MAX_GPIO_NUM);
+};
+
+/**
+ * struct ljca_i2c_info - ljca i2c client device info
+ *
+ * @id: ljca i2c client device identification number
+ * @capacity: ljca i2c client device capacity
+ * @intr_pin: ljca i2c client device interrupt pin number if exists
+ */
+struct ljca_i2c_info {
+       u8 id;
+       u8 capacity;
+       u8 intr_pin;
+};
+
+/**
+ * struct ljca_spi_info - ljca spi client device info
+ *
+ * @id: ljca spi client device identification number
+ * @capacity: ljca spi client device capacity
+ */
+struct ljca_spi_info {
+       u8 id;
+       u8 capacity;
+};
+
+/**
+ * ljca_register_event_cb - register a callback function to receive events
+ *
+ * @client: ljca client device
+ * @event_cb: callback function
+ * @context: execution context of event callback
+ *
+ * Return: 0 in case of success, negative value in case of error
+ */
+int ljca_register_event_cb(struct ljca_client *client, ljca_event_cb_t event_cb, void *context);
+
+/**
+ * ljca_unregister_event_cb - unregister the callback function for an event
+ *
+ * @client: ljca client device
+ */
+void ljca_unregister_event_cb(struct ljca_client *client);
+
+/**
+ * ljca_transfer - issue a LJCA command and wait for a response
+ *
+ * @client: ljca client device
+ * @cmd: the command to be sent to the device
+ * @obuf: the buffer to be sent to the device; it can be NULL if the user
+ *     doesn't need to transmit data with this command
+ * @obuf_len: the size of the buffer to be sent to the device; it should
+ *     be 0 when obuf is NULL
+ * @ibuf: any data associated with the response will be copied here; it can be
+ *     NULL if the user doesn't need the response data
+ * @ibuf_len: must be initialized to the input buffer size
+ *
+ * Return: the actual length of response data for success, negative value for errors
+ */
+int ljca_transfer(struct ljca_client *client, u8 cmd, const u8 *obuf,
+                 u8 obuf_len, u8 *ibuf, u8 ibuf_len);
+
+/**
+ * ljca_transfer_noack - issue a LJCA command without a response
+ *
+ * @client: ljca client device
+ * @cmd: the command to be sent to the device
+ * @obuf: the buffer to be sent to the device; it can be NULL if the user
+ *     doesn't need to transmit data with this command
+ * @obuf_len: the size of the buffer to be sent to the device
+ *
+ * Return: 0 for success, negative value for errors
+ */
+int ljca_transfer_noack(struct ljca_client *client, u8 cmd, const u8 *obuf,
+                       u8 obuf_len);
+
+#endif