--- /dev/null
+/*
+ * HID over I2C protocol implementation
+ *
+ * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
+ * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
+ * Copyright (c) 2012 Red Hat, Inc
+ *
+ * This code is partly based on "USB HID support for Linux":
+ *
+ * Copyright (c) 1999 Andreas Gal
+ * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
+ * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
+ * Copyright (c) 2007-2008 Oliver Neukum
+ * Copyright (c) 2006-2010 Jiri Kosina
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/device.h>
+#include <linux/wait.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/list.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/bug.h>
+#include <linux/hid.h>
+
+#include <linux/i2c/i2c-hid.h>
+
+/* flags */
+#define I2C_HID_STARTED (1 << 0)
+#define I2C_HID_RESET_PENDING (1 << 1)
+#define I2C_HID_READ_PENDING (1 << 2)
+
+#define I2C_HID_PWR_ON 0x00
+#define I2C_HID_PWR_SLEEP 0x01
+
+/* debug option */
+static bool debug = false;
+module_param(debug, bool, 0444);
+MODULE_PARM_DESC(debug, "print a lot of debug information");
+
+#define i2c_hid_dbg(ihid, fmt, arg...) \
+ if (debug) \
+ dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg)
+
+struct i2c_hid_desc {
+ __le16 wHIDDescLength;
+ __le16 bcdVersion;
+ __le16 wReportDescLength;
+ __le16 wReportDescRegister;
+ __le16 wInputRegister;
+ __le16 wMaxInputLength;
+ __le16 wOutputRegister;
+ __le16 wMaxOutputLength;
+ __le16 wCommandRegister;
+ __le16 wDataRegister;
+ __le16 wVendorID;
+ __le16 wProductID;
+ __le16 wVersionID;
+} __packed;
+
+struct i2c_hid_cmd {
+ unsigned int registerIndex;
+ __u8 opcode;
+ unsigned int length;
+ bool wait;
+};
+
+union command {
+ u8 data[0];
+ struct cmd {
+ __le16 reg;
+ __u8 reportTypeID;
+ __u8 opcode;
+ } __packed c;
+};
+
+#define I2C_HID_CMD(opcode_) \
+ .opcode = opcode_, .length = 4, \
+ .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
+
+/* fetch HID descriptor */
+static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
+/* fetch report descriptors */
+static const struct i2c_hid_cmd hid_report_descr_cmd = {
+ .registerIndex = offsetof(struct i2c_hid_desc,
+ wReportDescRegister),
+ .opcode = 0x00,
+ .length = 2 };
+/* commands */
+static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01),
+ .wait = true };
+static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) };
+static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) };
+static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
+static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
+static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
+static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
+static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) };
+/* read/write data register */
+static const struct i2c_hid_cmd hid_data_cmd = {
+ .registerIndex = offsetof(struct i2c_hid_desc, wDataRegister),
+ .opcode = 0x00,
+ .length = 2 };
+/* write output reports */
+static const struct i2c_hid_cmd hid_out_cmd = {
+ .registerIndex = offsetof(struct i2c_hid_desc,
+ wOutputRegister),
+ .opcode = 0x00,
+ .length = 2 };
+
+/* The main device structure */
+struct i2c_hid {
+ struct i2c_client *client; /* i2c client */
+ struct hid_device *hid; /* pointer to corresponding HID dev */
+ union {
+ __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
+ struct i2c_hid_desc hdesc; /* the HID Descriptor */
+ };
+ __le16 wHIDDescRegister; /* location of the i2c
+ * register of the HID
+ * descriptor. */
+ unsigned int bufsize; /* i2c buffer size */
+ char *inbuf; /* Input buffer */
+ char *cmdbuf; /* Command buffer */
+ char *argsbuf; /* Command arguments buffer */
+
+ unsigned long flags; /* device flags */
+
+ int irq; /* the interrupt line irq */
+
+ wait_queue_head_t wait; /* For waiting the interrupt */
+};
+
+static int __i2c_hid_command(struct i2c_client *client,
+ const struct i2c_hid_cmd *command, u8 reportID,
+ u8 reportType, u8 *args, int args_len,
+ unsigned char *buf_recv, int data_len)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ union command *cmd = (union command *)ihid->cmdbuf;
+ int ret;
+ struct i2c_msg msg[2];
+ int msg_num = 1;
+
+ int length = command->length;
+ bool wait = command->wait;
+ unsigned int registerIndex = command->registerIndex;
+
+ /* special case for hid_descr_cmd */
+ if (command == &hid_descr_cmd) {
+ cmd->c.reg = ihid->wHIDDescRegister;
+ } else {
+ cmd->data[0] = ihid->hdesc_buffer[registerIndex];
+ cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
+ }
+
+ if (length > 2) {
+ cmd->c.opcode = command->opcode;
+ cmd->c.reportTypeID = reportID | reportType << 4;
+ }
+
+ memcpy(cmd->data + length, args, args_len);
+ length += args_len;
+
+ i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
+
+ msg[0].addr = client->addr;
+ msg[0].flags = client->flags & I2C_M_TEN;
+ msg[0].len = length;
+ msg[0].buf = cmd->data;
+ if (data_len > 0) {
+ msg[1].addr = client->addr;
+ msg[1].flags = client->flags & I2C_M_TEN;
+ msg[1].flags |= I2C_M_RD;
+ msg[1].len = data_len;
+ msg[1].buf = buf_recv;
+ msg_num = 2;
+ set_bit(I2C_HID_READ_PENDING, &ihid->flags);
+ }
+
+ if (wait)
+ set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
+
+ ret = i2c_transfer(client->adapter, msg, msg_num);
+
+ if (data_len > 0)
+ clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
+
+ if (ret != msg_num)
+ return ret < 0 ? ret : -EIO;
+
+ ret = 0;
+
+ if (wait) {
+ i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
+ if (!wait_event_timeout(ihid->wait,
+ !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
+ msecs_to_jiffies(5000)))
+ ret = -ENODATA;
+ i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
+ }
+
+ return ret;
+}
+
+static int i2c_hid_command(struct i2c_client *client,
+ const struct i2c_hid_cmd *command,
+ unsigned char *buf_recv, int data_len)
+{
+ return __i2c_hid_command(client, command, 0, 0, NULL, 0,
+ buf_recv, data_len);
+}
+
+static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
+ u8 reportID, unsigned char *buf_recv, int data_len)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ u8 args[3];
+ int ret;
+ int args_len = 0;
+ u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
+
+ i2c_hid_dbg(ihid, "%s\n", __func__);
+
+ if (reportID >= 0x0F) {
+ args[args_len++] = reportID;
+ reportID = 0x0F;
+ }
+
+ args[args_len++] = readRegister & 0xFF;
+ args[args_len++] = readRegister >> 8;
+
+ ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
+ reportType, args, args_len, buf_recv, data_len);
+ if (ret) {
+ dev_err(&client->dev,
+ "failed to retrieve report from device.\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int i2c_hid_set_report(struct i2c_client *client, u8 reportType,
+ u8 reportID, unsigned char *buf, size_t data_len)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ u8 *args = ihid->argsbuf;
+ int ret;
+ u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
+
+ /* hidraw already checked that data_len < HID_MAX_BUFFER_SIZE */
+ u16 size = 2 /* size */ +
+ (reportID ? 1 : 0) /* reportID */ +
+ data_len /* buf */;
+ int args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
+ 2 /* dataRegister */ +
+ size /* args */;
+ int index = 0;
+
+ i2c_hid_dbg(ihid, "%s\n", __func__);
+
+ if (reportID >= 0x0F) {
+ args[index++] = reportID;
+ reportID = 0x0F;
+ }
+
+ args[index++] = dataRegister & 0xFF;
+ args[index++] = dataRegister >> 8;
+
+ args[index++] = size & 0xFF;
+ args[index++] = size >> 8;
+
+ if (reportID)
+ args[index++] = reportID;
+
+ memcpy(&args[index], buf, data_len);
+
+ ret = __i2c_hid_command(client, &hid_set_report_cmd, reportID,
+ reportType, args, args_len, NULL, 0);
+ if (ret) {
+ dev_err(&client->dev, "failed to set a report to device.\n");
+ return -EINVAL;
+ }
+
+ return data_len;
+}
+
+static int i2c_hid_set_power(struct i2c_client *client, int power_state)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret;
+
+ i2c_hid_dbg(ihid, "%s\n", __func__);
+
+ ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
+ 0, NULL, 0, NULL, 0);
+ if (ret)
+ dev_err(&client->dev, "failed to change power setting.\n");
+
+ return ret;
+}
+
+static int i2c_hid_hwreset(struct i2c_client *client)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret;
+
+ i2c_hid_dbg(ihid, "%s\n", __func__);
+
+ ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
+ if (ret)
+ return ret;
+
+ i2c_hid_dbg(ihid, "resetting...\n");
+
+ ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
+ if (ret) {
+ dev_err(&client->dev, "failed to reset device.\n");
+ i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int i2c_hid_get_input(struct i2c_hid *ihid)
+{
+ int ret, ret_size;
+ int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
+
+ ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
+ if (ret != size) {
+ if (ret < 0)
+ return ret;
+
+ dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
+ __func__, ret, size);
+ return ret;
+ }
+
+ ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
+
+ if (!ret_size) {
+ /* host or device initiated RESET completed */
+ if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
+ wake_up(&ihid->wait);
+ return 0;
+ }
+
+ if (ret_size > size) {
+ dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
+ __func__, size, ret_size);
+ return -EIO;
+ }
+
+ i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
+
+ if (test_bit(I2C_HID_STARTED, &ihid->flags))
+ hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
+ ret_size - 2, 1);
+
+ return 0;
+}
+
+static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
+{
+ struct i2c_hid *ihid = dev_id;
+
+ if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
+ return IRQ_HANDLED;
+
+ i2c_hid_get_input(ihid);
+
+ return IRQ_HANDLED;
+}
+
+static int i2c_hid_get_report_length(struct hid_report *report)
+{
+ return ((report->size - 1) >> 3) + 1 +
+ report->device->report_enum[report->type].numbered + 2;
+}
+
+static void i2c_hid_init_report(struct hid_report *report, u8 *buffer,
+ size_t bufsize)
+{
+ struct hid_device *hid = report->device;
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ unsigned int size, ret_size;
+
+ size = i2c_hid_get_report_length(report);
+ i2c_hid_get_report(client,
+ report->type == HID_FEATURE_REPORT ? 0x03 : 0x01,
+ report->id, buffer, size);
+
+ i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, ihid->inbuf);
+
+ ret_size = buffer[0] | (buffer[1] << 8);
+
+ if (ret_size != size) {
+ dev_err(&client->dev, "error in %s size:%d / ret_size:%d\n",
+ __func__, size, ret_size);
+ return;
+ }
+
+ /* hid->driver_lock is held as we are in probe function,
+ * we just need to setup the input fields, so using
+ * hid_report_raw_event is safe. */
+ hid_report_raw_event(hid, report->type, buffer + 2, size - 2, 1);
+}
+
+/*
+ * Initialize all reports
+ */
+static void i2c_hid_init_reports(struct hid_device *hid)
+{
+ struct hid_report *report;
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ u8 *inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
+
+ if (!inbuf)
+ return;
+
+ list_for_each_entry(report,
+ &hid->report_enum[HID_INPUT_REPORT].report_list, list)
+ i2c_hid_init_report(report, inbuf, ihid->bufsize);
+
+ list_for_each_entry(report,
+ &hid->report_enum[HID_FEATURE_REPORT].report_list, list)
+ i2c_hid_init_report(report, inbuf, ihid->bufsize);
+
+ kfree(inbuf);
+}
+
+/*
+ * Traverse the supplied list of reports and find the longest
+ */
+static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
+ unsigned int *max)
+{
+ struct hid_report *report;
+ unsigned int size;
+
+ /* We should not rely on wMaxInputLength, as some devices may set it to
+ * a wrong length. */
+ list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
+ size = i2c_hid_get_report_length(report);
+ if (*max < size)
+ *max = size;
+ }
+}
+
+static int i2c_hid_alloc_buffers(struct i2c_hid *ihid)
+{
+ /* the worst case is computed from the set_report command with a
+ * reportID > 15 and the maximum report length */
+ int args_len = sizeof(__u8) + /* optional ReportID byte */
+ sizeof(__u16) + /* data register */
+ sizeof(__u16) + /* size of the report */
+ ihid->bufsize; /* report */
+
+ ihid->inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
+
+ if (!ihid->inbuf)
+ return -ENOMEM;
+
+ ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
+
+ if (!ihid->argsbuf) {
+ kfree(ihid->inbuf);
+ return -ENOMEM;
+ }
+
+ ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
+
+ if (!ihid->cmdbuf) {
+ kfree(ihid->inbuf);
+ kfree(ihid->argsbuf);
+ ihid->inbuf = NULL;
+ ihid->argsbuf = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void i2c_hid_free_buffers(struct i2c_hid *ihid)
+{
+ kfree(ihid->inbuf);
+ kfree(ihid->argsbuf);
+ kfree(ihid->cmdbuf);
+ ihid->inbuf = NULL;
+ ihid->cmdbuf = NULL;
+ ihid->argsbuf = NULL;
+}
+
+static int i2c_hid_get_raw_report(struct hid_device *hid,
+ unsigned char report_number, __u8 *buf, size_t count,
+ unsigned char report_type)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret;
+
+ if (report_type == HID_OUTPUT_REPORT)
+ return -EINVAL;
+
+ if (count > ihid->bufsize)
+ count = ihid->bufsize;
+
+ ret = i2c_hid_get_report(client,
+ report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
+ report_number, ihid->inbuf, count);
+
+ if (ret < 0)
+ return ret;
+
+ count = ihid->inbuf[0] | (ihid->inbuf[1] << 8);
+
+ memcpy(buf, ihid->inbuf + 2, count);
+
+ return count;
+}
+
+static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
+ size_t count, unsigned char report_type)
+{
+ struct i2c_client *client = hid->driver_data;
+ int report_id = buf[0];
+
+ if (report_type == HID_INPUT_REPORT)
+ return -EINVAL;
+
+ return i2c_hid_set_report(client,
+ report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
+ report_id, buf, count);
+}
+
+static int i2c_hid_parse(struct hid_device *hid)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ struct i2c_hid_desc *hdesc = &ihid->hdesc;
+ unsigned int rsize;
+ char *rdesc;
+ int ret;
+ int tries = 3;
+
+ i2c_hid_dbg(ihid, "entering %s\n", __func__);
+
+ rsize = le16_to_cpu(hdesc->wReportDescLength);
+ if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
+ dbg_hid("weird size of report descriptor (%u)\n", rsize);
+ return -EINVAL;
+ }
+
+ do {
+ ret = i2c_hid_hwreset(client);
+ if (ret)
+ msleep(1000);
+ } while (tries-- > 0 && ret);
+
+ if (ret)
+ return ret;
+
+ rdesc = kzalloc(rsize, GFP_KERNEL);
+
+ if (!rdesc) {
+ dbg_hid("couldn't allocate rdesc memory\n");
+ return -ENOMEM;
+ }
+
+ i2c_hid_dbg(ihid, "asking HID report descriptor\n");
+
+ ret = i2c_hid_command(client, &hid_report_descr_cmd, rdesc, rsize);
+ if (ret) {
+ hid_err(hid, "reading report descriptor failed\n");
+ kfree(rdesc);
+ return -EIO;
+ }
+
+ i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
+
+ ret = hid_parse_report(hid, rdesc, rsize);
+ kfree(rdesc);
+ if (ret) {
+ dbg_hid("parsing report descriptor failed\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int i2c_hid_start(struct hid_device *hid)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret;
+ int old_bufsize = ihid->bufsize;
+
+ ihid->bufsize = HID_MIN_BUFFER_SIZE;
+ i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &ihid->bufsize);
+ i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &ihid->bufsize);
+ i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &ihid->bufsize);
+
+ if (ihid->bufsize > old_bufsize || !ihid->inbuf || !ihid->cmdbuf) {
+ i2c_hid_free_buffers(ihid);
+
+ ret = i2c_hid_alloc_buffers(ihid);
+
+ if (ret) {
+ ihid->bufsize = old_bufsize;
+ return ret;
+ }
+ }
+
+ if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
+ i2c_hid_init_reports(hid);
+
+ return 0;
+}
+
+static void i2c_hid_stop(struct hid_device *hid)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+
+ hid->claimed = 0;
+
+ i2c_hid_free_buffers(ihid);
+}
+
+static int i2c_hid_open(struct hid_device *hid)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret;
+
+ if (!hid->open++) {
+ ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
+ if (ret) {
+ hid->open--;
+ return -EIO;
+ }
+ set_bit(I2C_HID_STARTED, &ihid->flags);
+ }
+ return 0;
+}
+
+static void i2c_hid_close(struct hid_device *hid)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+
+ /* protecting hid->open to make sure we don't restart
+ * data acquistion due to a resumption we no longer
+ * care about
+ */
+ if (!--hid->open) {
+ clear_bit(I2C_HID_STARTED, &ihid->flags);
+
+ /* Save some power */
+ i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
+ }
+}
+
+static int i2c_hid_power(struct hid_device *hid, int lvl)
+{
+ struct i2c_client *client = hid->driver_data;
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret = 0;
+
+ i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
+
+ switch (lvl) {
+ case PM_HINT_FULLON:
+ ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
+ break;
+ case PM_HINT_NORMAL:
+ ret = i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
+ break;
+ }
+ return ret;
+}
+
+static int i2c_hid_hidinput_input_event(struct input_dev *dev,
+ unsigned int type, unsigned int code, int value)
+{
+ struct hid_device *hid = input_get_drvdata(dev);
+ struct hid_field *field;
+ int offset;
+
+ if (type == EV_FF)
+ return input_ff_event(dev, type, code, value);
+
+ if (type != EV_LED)
+ return -1;
+
+ offset = hidinput_find_field(hid, type, code, &field);
+
+ if (offset == -1) {
+ hid_warn(dev, "event field not found\n");
+ return -1;
+ }
+
+ hid_set_field(field, offset, value);
+
+ return 0;
+}
+
+static struct hid_ll_driver i2c_hid_ll_driver = {
+ .parse = i2c_hid_parse,
+ .start = i2c_hid_start,
+ .stop = i2c_hid_stop,
+ .open = i2c_hid_open,
+ .close = i2c_hid_close,
+ .power = i2c_hid_power,
+ .hidinput_input_event = i2c_hid_hidinput_input_event,
+};
+
+static int __devinit i2c_hid_init_irq(struct i2c_client *client)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ int ret;
+
+ dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
+
+ ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ client->name, ihid);
+ if (ret < 0) {
+ dev_dbg(&client->dev,
+ "Could not register for %s interrupt, irq = %d,"
+ " ret = %d\n",
+ client->name, client->irq, ret);
+
+ return ret;
+ }
+
+ ihid->irq = client->irq;
+
+ return 0;
+}
+
+static int __devinit i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
+{
+ struct i2c_client *client = ihid->client;
+ struct i2c_hid_desc *hdesc = &ihid->hdesc;
+ unsigned int dsize;
+ int ret;
+
+ /* Fetch the length of HID description, retrieve the 4 first bytes:
+ * bytes 0-1 -> length
+ * bytes 2-3 -> bcdVersion (has to be 1.00) */
+ ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer, 4);
+
+ i2c_hid_dbg(ihid, "%s, ihid->hdesc_buffer: %*ph\n",
+ __func__, 4, ihid->hdesc_buffer);
+
+ if (ret) {
+ dev_err(&client->dev, "HID_DESCR_LENGTH_CMD Fail (ret=%d)\n",
+ ret);
+ return -ENODEV;
+ }
+
+ dsize = le16_to_cpu(hdesc->wHIDDescLength);
+ if (!dsize || dsize > HID_MAX_DESCRIPTOR_SIZE) {
+ dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
+ dsize);
+ return -ENODEV;
+ }
+
+ /* check bcdVersion == 1.0 */
+ if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
+ dev_err(&client->dev,
+ "unexpected HID descriptor bcdVersion (0x%04x)\n",
+ le16_to_cpu(hdesc->bcdVersion));
+ return -ENODEV;
+ }
+
+ i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
+
+ ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer,
+ dsize);
+ if (ret) {
+ dev_err(&client->dev, "hid_descr_cmd Fail\n");
+ return -ENODEV;
+ }
+
+ i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
+
+ return 0;
+}
+
+static int __devinit i2c_hid_probe(struct i2c_client *client,
+ const struct i2c_device_id *dev_id)
+{
+ int ret;
+ struct i2c_hid *ihid;
+ struct hid_device *hid;
+ __u16 hidRegister;
+ struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
+
+ dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
+
+ if (!platform_data) {
+ dev_err(&client->dev, "HID register address not provided\n");
+ return -EINVAL;
+ }
+
+ if (!client->irq) {
+ dev_err(&client->dev,
+ "HID over i2c has not been provided an Int IRQ\n");
+ return -EINVAL;
+ }
+
+ ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL);
+ if (!ihid)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, ihid);
+
+ ihid->client = client;
+
+ hidRegister = platform_data->hid_descriptor_address;
+ ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
+
+ init_waitqueue_head(&ihid->wait);
+
+ /* we need to allocate the command buffer without knowing the maximum
+ * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
+ * real computation later. */
+ ihid->bufsize = HID_MIN_BUFFER_SIZE;
+ i2c_hid_alloc_buffers(ihid);
+
+ ret = i2c_hid_fetch_hid_descriptor(ihid);
+ if (ret < 0)
+ goto err;
+
+ ret = i2c_hid_init_irq(client);
+ if (ret < 0)
+ goto err;
+
+ hid = hid_allocate_device();
+ if (IS_ERR(hid)) {
+ ret = PTR_ERR(hid);
+ goto err;
+ }
+
+ ihid->hid = hid;
+
+ hid->driver_data = client;
+ hid->ll_driver = &i2c_hid_ll_driver;
+ hid->hid_get_raw_report = i2c_hid_get_raw_report;
+ hid->hid_output_raw_report = i2c_hid_output_raw_report;
+ hid->dev.parent = &client->dev;
+ hid->bus = BUS_I2C;
+ hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
+ hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
+ hid->product = le16_to_cpu(ihid->hdesc.wProductID);
+
+ snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
+ client->name, hid->vendor, hid->product);
+
+ ret = hid_add_device(hid);
+ if (ret) {
+ if (ret != -ENODEV)
+ hid_err(client, "can't add hid device: %d\n", ret);
+ goto err_mem_free;
+ }
+
+ return 0;
+
+err_mem_free:
+ hid_destroy_device(hid);
+
+err:
+ if (ihid->irq)
+ free_irq(ihid->irq, ihid);
+
+ kfree(ihid);
+ return ret;
+}
+
+static int __devexit i2c_hid_remove(struct i2c_client *client)
+{
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+ struct hid_device *hid;
+
+ if (WARN_ON(!ihid))
+ return -1;
+
+ hid = ihid->hid;
+ hid_destroy_device(hid);
+
+ free_irq(client->irq, ihid);
+
+ kfree(ihid);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int i2c_hid_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct i2c_hid *ihid = i2c_get_clientdata(client);
+
+ if (device_may_wakeup(&client->dev))
+ enable_irq_wake(ihid->irq);
+
+ /* Save some power */
+ i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
+
+ return 0;
+}
+
+static int i2c_hid_resume(struct device *dev)
+{
+ int ret;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ ret = i2c_hid_hwreset(client);
+ if (ret)
+ return ret;
+
+ if (device_may_wakeup(&client->dev))
+ disable_irq_wake(client->irq);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(i2c_hid_pm, i2c_hid_suspend, i2c_hid_resume);
+
+static const struct i2c_device_id i2c_hid_id_table[] = {
+ { "i2c_hid", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
+
+
+static struct i2c_driver i2c_hid_driver = {
+ .driver = {
+ .name = "i2c_hid",
+ .owner = THIS_MODULE,
+ .pm = &i2c_hid_pm,
+ },
+
+ .probe = i2c_hid_probe,
+ .remove = __devexit_p(i2c_hid_remove),
+
+ .id_table = i2c_hid_id_table,
+};
+
+module_i2c_driver(i2c_hid_driver);
+
+MODULE_DESCRIPTION("HID over I2C core driver");
+MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
+MODULE_LICENSE("GPL");
projects / GitHub / moto-9609 / android_kernel_motorola_exynos9610.git / commitdiff