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path: root/drivers/misc/mei/vsc-tp.c
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Diffstat (limited to 'drivers/misc/mei/vsc-tp.c')
-rw-r--r--drivers/misc/mei/vsc-tp.c593
1 files changed, 593 insertions, 0 deletions
diff --git a/drivers/misc/mei/vsc-tp.c b/drivers/misc/mei/vsc-tp.c
new file mode 100644
index 0000000000..870c70ef3b
--- /dev/null
+++ b/drivers/misc/mei/vsc-tp.c
@@ -0,0 +1,593 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023, Intel Corporation.
+ * Intel Visual Sensing Controller Transport Layer Linux driver
+ */
+
+#include <linux/acpi.h>
+#include <linux/cleanup.h>
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+
+#include "vsc-tp.h"
+
+#define VSC_TP_RESET_PIN_TOGGLE_INTERVAL_MS 20
+#define VSC_TP_ROM_BOOTUP_DELAY_MS 10
+#define VSC_TP_ROM_XFER_POLL_TIMEOUT_US (500 * USEC_PER_MSEC)
+#define VSC_TP_ROM_XFER_POLL_DELAY_US (20 * USEC_PER_MSEC)
+#define VSC_TP_WAIT_FW_POLL_TIMEOUT (2 * HZ)
+#define VSC_TP_WAIT_FW_POLL_DELAY_US (20 * USEC_PER_MSEC)
+#define VSC_TP_MAX_XFER_COUNT 5
+
+#define VSC_TP_PACKET_SYNC 0x31
+#define VSC_TP_CRC_SIZE sizeof(u32)
+#define VSC_TP_MAX_MSG_SIZE 2048
+/* SPI xfer timeout size */
+#define VSC_TP_XFER_TIMEOUT_BYTES 700
+#define VSC_TP_PACKET_PADDING_SIZE 1
+#define VSC_TP_PACKET_SIZE(pkt) \
+ (sizeof(struct vsc_tp_packet) + le16_to_cpu((pkt)->len) + VSC_TP_CRC_SIZE)
+#define VSC_TP_MAX_PACKET_SIZE \
+ (sizeof(struct vsc_tp_packet) + VSC_TP_MAX_MSG_SIZE + VSC_TP_CRC_SIZE)
+#define VSC_TP_MAX_XFER_SIZE \
+ (VSC_TP_MAX_PACKET_SIZE + VSC_TP_XFER_TIMEOUT_BYTES)
+#define VSC_TP_NEXT_XFER_LEN(len, offset) \
+ (len + sizeof(struct vsc_tp_packet) + VSC_TP_CRC_SIZE - offset + VSC_TP_PACKET_PADDING_SIZE)
+
+struct vsc_tp_packet {
+ __u8 sync;
+ __u8 cmd;
+ __le16 len;
+ __le32 seq;
+ __u8 buf[] __counted_by(len);
+};
+
+struct vsc_tp {
+ /* do the actual data transfer */
+ struct spi_device *spi;
+
+ /* bind with mei framework */
+ struct platform_device *pdev;
+
+ struct gpio_desc *wakeuphost;
+ struct gpio_desc *resetfw;
+ struct gpio_desc *wakeupfw;
+
+ /* command sequence number */
+ u32 seq;
+
+ /* command buffer */
+ void *tx_buf;
+ void *rx_buf;
+
+ atomic_t assert_cnt;
+ wait_queue_head_t xfer_wait;
+
+ vsc_tp_event_cb_t event_notify;
+ void *event_notify_context;
+
+ /* used to protect command download */
+ struct mutex mutex;
+};
+
+/* GPIO resources */
+static const struct acpi_gpio_params wakeuphost_gpio = { 0, 0, false };
+static const struct acpi_gpio_params wakeuphostint_gpio = { 1, 0, false };
+static const struct acpi_gpio_params resetfw_gpio = { 2, 0, false };
+static const struct acpi_gpio_params wakeupfw = { 3, 0, false };
+
+static const struct acpi_gpio_mapping vsc_tp_acpi_gpios[] = {
+ { "wakeuphost-gpios", &wakeuphost_gpio, 1 },
+ { "wakeuphostint-gpios", &wakeuphostint_gpio, 1 },
+ { "resetfw-gpios", &resetfw_gpio, 1 },
+ { "wakeupfw-gpios", &wakeupfw, 1 },
+ {}
+};
+
+static irqreturn_t vsc_tp_isr(int irq, void *data)
+{
+ struct vsc_tp *tp = data;
+
+ atomic_inc(&tp->assert_cnt);
+
+ wake_up(&tp->xfer_wait);
+
+ return IRQ_WAKE_THREAD;
+}
+
+static irqreturn_t vsc_tp_thread_isr(int irq, void *data)
+{
+ struct vsc_tp *tp = data;
+
+ if (tp->event_notify)
+ tp->event_notify(tp->event_notify_context);
+
+ return IRQ_HANDLED;
+}
+
+/* wakeup firmware and wait for response */
+static int vsc_tp_wakeup_request(struct vsc_tp *tp)
+{
+ int ret;
+
+ gpiod_set_value_cansleep(tp->wakeupfw, 0);
+
+ ret = wait_event_timeout(tp->xfer_wait,
+ atomic_read(&tp->assert_cnt),
+ VSC_TP_WAIT_FW_POLL_TIMEOUT);
+ if (!ret)
+ return -ETIMEDOUT;
+
+ return read_poll_timeout(gpiod_get_value_cansleep, ret, ret,
+ VSC_TP_WAIT_FW_POLL_DELAY_US,
+ VSC_TP_WAIT_FW_POLL_TIMEOUT, false,
+ tp->wakeuphost);
+}
+
+static void vsc_tp_wakeup_release(struct vsc_tp *tp)
+{
+ atomic_dec_if_positive(&tp->assert_cnt);
+
+ gpiod_set_value_cansleep(tp->wakeupfw, 1);
+}
+
+static int vsc_tp_dev_xfer(struct vsc_tp *tp, void *obuf, void *ibuf, size_t len)
+{
+ struct spi_message msg = { 0 };
+ struct spi_transfer xfer = {
+ .tx_buf = obuf,
+ .rx_buf = ibuf,
+ .len = len,
+ };
+
+ spi_message_init_with_transfers(&msg, &xfer, 1);
+
+ return spi_sync_locked(tp->spi, &msg);
+}
+
+static int vsc_tp_xfer_helper(struct vsc_tp *tp, struct vsc_tp_packet *pkt,
+ void *ibuf, u16 ilen)
+{
+ int ret, offset = 0, cpy_len, src_len, dst_len = sizeof(struct vsc_tp_packet);
+ int next_xfer_len = VSC_TP_PACKET_SIZE(pkt) + VSC_TP_XFER_TIMEOUT_BYTES;
+ u8 *src, *crc_src, *rx_buf = tp->rx_buf;
+ int count_down = VSC_TP_MAX_XFER_COUNT;
+ u32 recv_crc = 0, crc = ~0;
+ struct vsc_tp_packet ack;
+ u8 *dst = (u8 *)&ack;
+ bool synced = false;
+
+ do {
+ ret = vsc_tp_dev_xfer(tp, pkt, rx_buf, next_xfer_len);
+ if (ret)
+ return ret;
+ memset(pkt, 0, VSC_TP_MAX_XFER_SIZE);
+
+ if (synced) {
+ src = rx_buf;
+ src_len = next_xfer_len;
+ } else {
+ src = memchr(rx_buf, VSC_TP_PACKET_SYNC, next_xfer_len);
+ if (!src)
+ continue;
+ synced = true;
+ src_len = next_xfer_len - (src - rx_buf);
+ }
+
+ /* traverse received data */
+ while (src_len > 0) {
+ cpy_len = min(src_len, dst_len);
+ memcpy(dst, src, cpy_len);
+ crc_src = src;
+ src += cpy_len;
+ src_len -= cpy_len;
+ dst += cpy_len;
+ dst_len -= cpy_len;
+
+ if (offset < sizeof(ack)) {
+ offset += cpy_len;
+ crc = crc32(crc, crc_src, cpy_len);
+
+ if (!src_len)
+ continue;
+
+ if (le16_to_cpu(ack.len)) {
+ dst = ibuf;
+ dst_len = min(ilen, le16_to_cpu(ack.len));
+ } else {
+ dst = (u8 *)&recv_crc;
+ dst_len = sizeof(recv_crc);
+ }
+ } else if (offset < sizeof(ack) + le16_to_cpu(ack.len)) {
+ offset += cpy_len;
+ crc = crc32(crc, crc_src, cpy_len);
+
+ if (src_len) {
+ int remain = sizeof(ack) + le16_to_cpu(ack.len) - offset;
+
+ cpy_len = min(src_len, remain);
+ offset += cpy_len;
+ crc = crc32(crc, src, cpy_len);
+ src += cpy_len;
+ src_len -= cpy_len;
+ if (src_len) {
+ dst = (u8 *)&recv_crc;
+ dst_len = sizeof(recv_crc);
+ continue;
+ }
+ }
+ next_xfer_len = VSC_TP_NEXT_XFER_LEN(le16_to_cpu(ack.len), offset);
+ } else if (offset < sizeof(ack) + le16_to_cpu(ack.len) + VSC_TP_CRC_SIZE) {
+ offset += cpy_len;
+
+ if (src_len) {
+ /* terminate the traverse */
+ next_xfer_len = 0;
+ break;
+ }
+ next_xfer_len = VSC_TP_NEXT_XFER_LEN(le16_to_cpu(ack.len), offset);
+ }
+ }
+ } while (next_xfer_len > 0 && --count_down);
+
+ if (next_xfer_len > 0)
+ return -EAGAIN;
+
+ if (~recv_crc != crc || le32_to_cpu(ack.seq) != tp->seq) {
+ dev_err(&tp->spi->dev, "recv crc or seq error\n");
+ return -EINVAL;
+ }
+
+ if (ack.cmd == VSC_TP_CMD_ACK || ack.cmd == VSC_TP_CMD_NACK ||
+ ack.cmd == VSC_TP_CMD_BUSY) {
+ dev_err(&tp->spi->dev, "recv cmd ack error\n");
+ return -EAGAIN;
+ }
+
+ return min(le16_to_cpu(ack.len), ilen);
+}
+
+/**
+ * vsc_tp_xfer - transfer data to firmware
+ * @tp: vsc_tp device handle
+ * @cmd: the command to be sent to the device
+ * @obuf: the tx buffer to be sent to the device
+ * @olen: the length of tx buffer
+ * @ibuf: the rx buffer to receive from the device
+ * @ilen: the length of rx buffer
+ * Return: the length of received data in case of success,
+ * otherwise negative value
+ */
+int vsc_tp_xfer(struct vsc_tp *tp, u8 cmd, const void *obuf, size_t olen,
+ void *ibuf, size_t ilen)
+{
+ struct vsc_tp_packet *pkt = tp->tx_buf;
+ u32 crc;
+ int ret;
+
+ if (!obuf || !ibuf || olen > VSC_TP_MAX_MSG_SIZE)
+ return -EINVAL;
+
+ guard(mutex)(&tp->mutex);
+
+ pkt->sync = VSC_TP_PACKET_SYNC;
+ pkt->cmd = cmd;
+ pkt->len = cpu_to_le16(olen);
+ pkt->seq = cpu_to_le32(++tp->seq);
+ memcpy(pkt->buf, obuf, olen);
+
+ crc = ~crc32(~0, (u8 *)pkt, sizeof(pkt) + olen);
+ memcpy(pkt->buf + olen, &crc, sizeof(crc));
+
+ ret = vsc_tp_wakeup_request(tp);
+ if (unlikely(ret))
+ dev_err(&tp->spi->dev, "wakeup firmware failed ret: %d\n", ret);
+ else
+ ret = vsc_tp_xfer_helper(tp, pkt, ibuf, ilen);
+
+ vsc_tp_wakeup_release(tp);
+
+ return ret;
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_xfer, VSC_TP);
+
+/**
+ * vsc_tp_rom_xfer - transfer data to rom code
+ * @tp: vsc_tp device handle
+ * @obuf: the data buffer to be sent to the device
+ * @ibuf: the buffer to receive data from the device
+ * @len: the length of tx buffer and rx buffer
+ * Return: 0 in case of success, negative value in case of error
+ */
+int vsc_tp_rom_xfer(struct vsc_tp *tp, const void *obuf, void *ibuf, size_t len)
+{
+ size_t words = len / sizeof(__be32);
+ int ret;
+
+ if (len % sizeof(__be32) || len > VSC_TP_MAX_MSG_SIZE)
+ return -EINVAL;
+
+ guard(mutex)(&tp->mutex);
+
+ /* rom xfer is big endian */
+ cpu_to_be32_array(tp->tx_buf, obuf, words);
+
+ ret = read_poll_timeout(gpiod_get_value_cansleep, ret,
+ !ret, VSC_TP_ROM_XFER_POLL_DELAY_US,
+ VSC_TP_ROM_XFER_POLL_TIMEOUT_US, false,
+ tp->wakeuphost);
+ if (ret) {
+ dev_err(&tp->spi->dev, "wait rom failed ret: %d\n", ret);
+ return ret;
+ }
+
+ ret = vsc_tp_dev_xfer(tp, tp->tx_buf, tp->rx_buf, len);
+ if (ret)
+ return ret;
+
+ if (ibuf)
+ cpu_to_be32_array(ibuf, tp->rx_buf, words);
+
+ return ret;
+}
+
+/**
+ * vsc_tp_reset - reset vsc transport layer
+ * @tp: vsc_tp device handle
+ */
+void vsc_tp_reset(struct vsc_tp *tp)
+{
+ disable_irq(tp->spi->irq);
+
+ /* toggle reset pin */
+ gpiod_set_value_cansleep(tp->resetfw, 0);
+ msleep(VSC_TP_RESET_PIN_TOGGLE_INTERVAL_MS);
+ gpiod_set_value_cansleep(tp->resetfw, 1);
+
+ /* wait for ROM */
+ msleep(VSC_TP_ROM_BOOTUP_DELAY_MS);
+
+ /*
+ * Set default host wakeup pin to non-active
+ * to avoid unexpected host irq interrupt.
+ */
+ gpiod_set_value_cansleep(tp->wakeupfw, 1);
+
+ atomic_set(&tp->assert_cnt, 0);
+
+ enable_irq(tp->spi->irq);
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_reset, VSC_TP);
+
+/**
+ * vsc_tp_need_read - check if device has data to sent
+ * @tp: vsc_tp device handle
+ * Return: true if device has data to sent, otherwise false
+ */
+bool vsc_tp_need_read(struct vsc_tp *tp)
+{
+ if (!atomic_read(&tp->assert_cnt))
+ return false;
+ if (!gpiod_get_value_cansleep(tp->wakeuphost))
+ return false;
+ if (!gpiod_get_value_cansleep(tp->wakeupfw))
+ return false;
+
+ return true;
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_need_read, VSC_TP);
+
+/**
+ * vsc_tp_register_event_cb - register a callback function to receive event
+ * @tp: vsc_tp device handle
+ * @event_cb: callback function
+ * @context: execution context of event callback
+ * Return: 0 in case of success, negative value in case of error
+ */
+int vsc_tp_register_event_cb(struct vsc_tp *tp, vsc_tp_event_cb_t event_cb,
+ void *context)
+{
+ tp->event_notify = event_cb;
+ tp->event_notify_context = context;
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_register_event_cb, VSC_TP);
+
+/**
+ * vsc_tp_request_irq - request irq for vsc_tp device
+ * @tp: vsc_tp device handle
+ */
+int vsc_tp_request_irq(struct vsc_tp *tp)
+{
+ struct spi_device *spi = tp->spi;
+ struct device *dev = &spi->dev;
+ int ret;
+
+ irq_set_status_flags(spi->irq, IRQ_DISABLE_UNLAZY);
+ ret = request_threaded_irq(spi->irq, vsc_tp_isr, vsc_tp_thread_isr,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ dev_name(dev), tp);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_request_irq, VSC_TP);
+
+/**
+ * vsc_tp_free_irq - free irq for vsc_tp device
+ * @tp: vsc_tp device handle
+ */
+void vsc_tp_free_irq(struct vsc_tp *tp)
+{
+ free_irq(tp->spi->irq, tp);
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_free_irq, VSC_TP);
+
+/**
+ * vsc_tp_intr_synchronize - synchronize vsc_tp interrupt
+ * @tp: vsc_tp device handle
+ */
+void vsc_tp_intr_synchronize(struct vsc_tp *tp)
+{
+ synchronize_irq(tp->spi->irq);
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_intr_synchronize, VSC_TP);
+
+/**
+ * vsc_tp_intr_enable - enable vsc_tp interrupt
+ * @tp: vsc_tp device handle
+ */
+void vsc_tp_intr_enable(struct vsc_tp *tp)
+{
+ enable_irq(tp->spi->irq);
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_intr_enable, VSC_TP);
+
+/**
+ * vsc_tp_intr_disable - disable vsc_tp interrupt
+ * @tp: vsc_tp device handle
+ */
+void vsc_tp_intr_disable(struct vsc_tp *tp)
+{
+ disable_irq(tp->spi->irq);
+}
+EXPORT_SYMBOL_NS_GPL(vsc_tp_intr_disable, VSC_TP);
+
+static int vsc_tp_match_any(struct acpi_device *adev, void *data)
+{
+ struct acpi_device **__adev = data;
+
+ *__adev = adev;
+
+ return 1;
+}
+
+static int vsc_tp_probe(struct spi_device *spi)
+{
+ struct platform_device_info pinfo = { 0 };
+ struct device *dev = &spi->dev;
+ struct platform_device *pdev;
+ struct acpi_device *adev;
+ struct vsc_tp *tp;
+ int ret;
+
+ tp = devm_kzalloc(dev, sizeof(*tp), GFP_KERNEL);
+ if (!tp)
+ return -ENOMEM;
+
+ tp->tx_buf = devm_kzalloc(dev, VSC_TP_MAX_XFER_SIZE, GFP_KERNEL);
+ if (!tp->tx_buf)
+ return -ENOMEM;
+
+ tp->rx_buf = devm_kzalloc(dev, VSC_TP_MAX_XFER_SIZE, GFP_KERNEL);
+ if (!tp->rx_buf)
+ return -ENOMEM;
+
+ ret = devm_acpi_dev_add_driver_gpios(dev, vsc_tp_acpi_gpios);
+ if (ret)
+ return ret;
+
+ tp->wakeuphost = devm_gpiod_get(dev, "wakeuphost", GPIOD_IN);
+ if (IS_ERR(tp->wakeuphost))
+ return PTR_ERR(tp->wakeuphost);
+
+ tp->resetfw = devm_gpiod_get(dev, "resetfw", GPIOD_OUT_HIGH);
+ if (IS_ERR(tp->resetfw))
+ return PTR_ERR(tp->resetfw);
+
+ tp->wakeupfw = devm_gpiod_get(dev, "wakeupfw", GPIOD_OUT_HIGH);
+ if (IS_ERR(tp->wakeupfw))
+ return PTR_ERR(tp->wakeupfw);
+
+ atomic_set(&tp->assert_cnt, 0);
+ init_waitqueue_head(&tp->xfer_wait);
+ tp->spi = spi;
+
+ irq_set_status_flags(spi->irq, IRQ_DISABLE_UNLAZY);
+ ret = request_threaded_irq(spi->irq, vsc_tp_isr, vsc_tp_thread_isr,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ dev_name(dev), tp);
+ if (ret)
+ return ret;
+
+ mutex_init(&tp->mutex);
+
+ /* only one child acpi device */
+ ret = acpi_dev_for_each_child(ACPI_COMPANION(dev),
+ vsc_tp_match_any, &adev);
+ if (!ret) {
+ ret = -ENODEV;
+ goto err_destroy_lock;
+ }
+ pinfo.fwnode = acpi_fwnode_handle(adev);
+
+ pinfo.name = "intel_vsc";
+ pinfo.data = &tp;
+ pinfo.size_data = sizeof(tp);
+ pinfo.id = PLATFORM_DEVID_NONE;
+
+ pdev = platform_device_register_full(&pinfo);
+ if (IS_ERR(pdev)) {
+ ret = PTR_ERR(pdev);
+ goto err_destroy_lock;
+ }
+
+ tp->pdev = pdev;
+ spi_set_drvdata(spi, tp);
+
+ return 0;
+
+err_destroy_lock:
+ mutex_destroy(&tp->mutex);
+
+ free_irq(spi->irq, tp);
+
+ return ret;
+}
+
+static void vsc_tp_remove(struct spi_device *spi)
+{
+ struct vsc_tp *tp = spi_get_drvdata(spi);
+
+ platform_device_unregister(tp->pdev);
+
+ mutex_destroy(&tp->mutex);
+
+ free_irq(spi->irq, tp);
+}
+
+static const struct acpi_device_id vsc_tp_acpi_ids[] = {
+ { "INTC1009" }, /* Raptor Lake */
+ { "INTC1058" }, /* Tiger Lake */
+ { "INTC1094" }, /* Alder Lake */
+ { "INTC10D0" }, /* Meteor Lake */
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, vsc_tp_acpi_ids);
+
+static struct spi_driver vsc_tp_driver = {
+ .probe = vsc_tp_probe,
+ .remove = vsc_tp_remove,
+ .driver = {
+ .name = "vsc-tp",
+ .acpi_match_table = vsc_tp_acpi_ids,
+ },
+};
+module_spi_driver(vsc_tp_driver);
+
+MODULE_AUTHOR("Wentong Wu <wentong.wu@intel.com>");
+MODULE_AUTHOR("Zhifeng Wang <zhifeng.wang@intel.com>");
+MODULE_DESCRIPTION("Intel Visual Sensing Controller Transport Layer");
+MODULE_LICENSE("GPL");