| /* |
| * 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/pm_runtime.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/hid.h> |
| #include <linux/mutex.h> |
| #include <linux/acpi.h> |
| #include <linux/of.h> |
| #include <linux/gpio/consumer.h> |
| |
| #include <linux/i2c/i2c-hid.h> |
| |
| /* flags */ |
| #define I2C_HID_STARTED 0 |
| #define I2C_HID_RESET_PENDING 1 |
| #define I2C_HID_READ_PENDING 2 |
| |
| #define I2C_HID_PWR_ON 0x00 |
| #define I2C_HID_PWR_SLEEP 0x01 |
| |
| /* debug option */ |
| static bool debug; |
| module_param(debug, bool, 0444); |
| MODULE_PARM_DESC(debug, "print a lot of debug information"); |
| |
| #define i2c_hid_dbg(ihid, fmt, arg...) \ |
| do { \ |
| if (debug) \ |
| dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \ |
| } while (0) |
| |
| 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; |
| __le32 reserved; |
| } __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_set_power_cmd = { I2C_HID_CMD(0x08) }; |
| static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 }; |
| |
| /* |
| * These definitions are not used here, but are defined by the spec. |
| * Keeping them here for documentation purposes. |
| * |
| * 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 DEFINE_MUTEX(i2c_hid_open_mut); |
| |
| /* 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 *rawbuf; /* Raw Input buffer */ |
| char *cmdbuf; /* Command buffer */ |
| char *argsbuf; /* Command arguments buffer */ |
| |
| unsigned long flags; /* device flags */ |
| |
| wait_queue_head_t wait; /* For waiting the interrupt */ |
| struct gpio_desc *desc; |
| int irq; |
| |
| struct i2c_hid_platform_data pdata; |
| |
| bool irq_wake_enabled; |
| }; |
| |
| 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 ret; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * i2c_hid_set_or_send_report: forward an incoming report to the device |
| * @client: the i2c_client of the device |
| * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT |
| * @reportID: the report ID |
| * @buf: the actual data to transfer, without the report ID |
| * @len: size of buf |
| * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report |
| */ |
| static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType, |
| u8 reportID, unsigned char *buf, size_t data_len, bool use_data) |
| { |
| struct i2c_hid *ihid = i2c_get_clientdata(client); |
| u8 *args = ihid->argsbuf; |
| const struct i2c_hid_cmd *hidcmd; |
| int ret; |
| u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister); |
| u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister); |
| u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength); |
| |
| /* hid_hw_* 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 (!use_data && maxOutputLength == 0) |
| return -ENOSYS; |
| |
| if (reportID >= 0x0F) { |
| args[index++] = reportID; |
| reportID = 0x0F; |
| } |
| |
| /* |
| * use the data register for feature reports or if the device does not |
| * support the output register |
| */ |
| if (use_data) { |
| args[index++] = dataRegister & 0xFF; |
| args[index++] = dataRegister >> 8; |
| hidcmd = &hid_set_report_cmd; |
| } else { |
| args[index++] = outputRegister & 0xFF; |
| args[index++] = outputRegister >> 8; |
| hidcmd = &hid_no_cmd; |
| } |
| |
| args[index++] = size & 0xFF; |
| args[index++] = size >> 8; |
| |
| if (reportID) |
| args[index++] = reportID; |
| |
| memcpy(&args[index], buf, data_len); |
| |
| ret = __i2c_hid_command(client, hidcmd, reportID, |
| reportType, args, args_len, NULL, 0); |
| if (ret) { |
| dev_err(&client->dev, "failed to set a report to device.\n"); |
| return ret; |
| } |
| |
| 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 void i2c_hid_get_input(struct i2c_hid *ihid) |
| { |
| int ret, ret_size; |
| int size = le16_to_cpu(ihid->hdesc.wMaxInputLength); |
| |
| if (size > ihid->bufsize) |
| size = ihid->bufsize; |
| |
| ret = i2c_master_recv(ihid->client, ihid->inbuf, size); |
| if (ret != size) { |
| if (ret < 0) |
| return; |
| |
| dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n", |
| __func__, ret, size); |
| return; |
| } |
| |
| 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; |
| } |
| |
| if (ret_size > size) { |
| dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n", |
| __func__, size, ret_size); |
| return; |
| } |
| |
| 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; |
| } |
| |
| 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); |
| if (i2c_hid_get_report(client, |
| report->type == HID_FEATURE_REPORT ? 0x03 : 0x01, |
| report->id, buffer, size)) |
| return; |
| |
| i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, buffer); |
| |
| 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) { |
| dev_err(&client->dev, "can not retrieve initial reports\n"); |
| return; |
| } |
| |
| /* |
| * The device must be powered on while we fetch initial reports |
| * from it. |
| */ |
| pm_runtime_get_sync(&client->dev); |
| |
| list_for_each_entry(report, |
| &hid->report_enum[HID_FEATURE_REPORT].report_list, list) |
| i2c_hid_init_report(report, inbuf, ihid->bufsize); |
| |
| pm_runtime_put(&client->dev); |
| |
| 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 void i2c_hid_free_buffers(struct i2c_hid *ihid) |
| { |
| kfree(ihid->inbuf); |
| kfree(ihid->rawbuf); |
| kfree(ihid->argsbuf); |
| kfree(ihid->cmdbuf); |
| ihid->inbuf = NULL; |
| ihid->rawbuf = NULL; |
| ihid->cmdbuf = NULL; |
| ihid->argsbuf = NULL; |
| ihid->bufsize = 0; |
| } |
| |
| static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size) |
| { |
| /* 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 */ |
| report_size; /* report */ |
| |
| ihid->inbuf = kzalloc(report_size, GFP_KERNEL); |
| ihid->rawbuf = kzalloc(report_size, GFP_KERNEL); |
| ihid->argsbuf = kzalloc(args_len, GFP_KERNEL); |
| ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL); |
| |
| if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) { |
| i2c_hid_free_buffers(ihid); |
| return -ENOMEM; |
| } |
| |
| ihid->bufsize = report_size; |
| |
| return 0; |
| } |
| |
| 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); |
| size_t ret_count, ask_count; |
| int ret; |
| |
| if (report_type == HID_OUTPUT_REPORT) |
| return -EINVAL; |
| |
| /* +2 bytes to include the size of the reply in the query buffer */ |
| ask_count = min(count + 2, (size_t)ihid->bufsize); |
| |
| ret = i2c_hid_get_report(client, |
| report_type == HID_FEATURE_REPORT ? 0x03 : 0x01, |
| report_number, ihid->rawbuf, ask_count); |
| |
| if (ret < 0) |
| return ret; |
| |
| ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8); |
| |
| if (ret_count <= 2) |
| return 0; |
| |
| ret_count = min(ret_count, ask_count); |
| |
| /* The query buffer contains the size, dropping it in the reply */ |
| count = min(count, ret_count - 2); |
| memcpy(buf, ihid->rawbuf + 2, count); |
| |
| return count; |
| } |
| |
| static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf, |
| size_t count, unsigned char report_type, bool use_data) |
| { |
| struct i2c_client *client = hid->driver_data; |
| int report_id = buf[0]; |
| int ret; |
| |
| if (report_type == HID_INPUT_REPORT) |
| return -EINVAL; |
| |
| if (report_id) { |
| buf++; |
| count--; |
| } |
| |
| ret = i2c_hid_set_or_send_report(client, |
| report_type == HID_FEATURE_REPORT ? 0x03 : 0x02, |
| report_id, buf, count, use_data); |
| |
| if (report_id && ret >= 0) |
| ret++; /* add report_id to the number of transfered bytes */ |
| |
| return ret; |
| } |
| |
| static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf, |
| size_t count) |
| { |
| return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT, |
| false); |
| } |
| |
| static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum, |
| __u8 *buf, size_t len, unsigned char rtype, |
| int reqtype) |
| { |
| switch (reqtype) { |
| case HID_REQ_GET_REPORT: |
| return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype); |
| case HID_REQ_SET_REPORT: |
| if (buf[0] != reportnum) |
| return -EINVAL; |
| return i2c_hid_output_raw_report(hid, buf, len, rtype, true); |
| default: |
| return -EIO; |
| } |
| } |
| |
| 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; |
| unsigned int bufsize = HID_MIN_BUFFER_SIZE; |
| |
| i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize); |
| i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize); |
| i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize); |
| |
| if (bufsize > ihid->bufsize) { |
| i2c_hid_free_buffers(ihid); |
| |
| ret = i2c_hid_alloc_buffers(ihid, bufsize); |
| |
| if (ret) |
| 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) |
| { |
| hid->claimed = 0; |
| } |
| |
| 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 = 0; |
| |
| mutex_lock(&i2c_hid_open_mut); |
| if (!hid->open++) { |
| ret = pm_runtime_get_sync(&client->dev); |
| if (ret < 0) { |
| hid->open--; |
| goto done; |
| } |
| set_bit(I2C_HID_STARTED, &ihid->flags); |
| } |
| done: |
| mutex_unlock(&i2c_hid_open_mut); |
| return ret < 0 ? ret : 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 |
| */ |
| mutex_lock(&i2c_hid_open_mut); |
| if (!--hid->open) { |
| clear_bit(I2C_HID_STARTED, &ihid->flags); |
| |
| /* Save some power */ |
| pm_runtime_put(&client->dev); |
| } |
| mutex_unlock(&i2c_hid_open_mut); |
| } |
| |
| 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); |
| |
| i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl); |
| |
| switch (lvl) { |
| case PM_HINT_FULLON: |
| pm_runtime_get_sync(&client->dev); |
| break; |
| case PM_HINT_NORMAL: |
| pm_runtime_put(&client->dev); |
| break; |
| } |
| 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, |
| .output_report = i2c_hid_output_report, |
| .raw_request = i2c_hid_raw_request, |
| }; |
| |
| static int 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", ihid->irq); |
| |
| ret = request_threaded_irq(ihid->irq, NULL, i2c_hid_irq, |
| IRQF_TRIGGER_LOW | IRQF_ONESHOT, |
| client->name, ihid); |
| if (ret < 0) { |
| dev_warn(&client->dev, |
| "Could not register for %s interrupt, irq = %d," |
| " ret = %d\n", |
| client->name, ihid->irq, ret); |
| |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int 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; |
| |
| /* i2c hid fetch using a fixed descriptor size (30 bytes) */ |
| i2c_hid_dbg(ihid, "Fetching the HID descriptor\n"); |
| ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer, |
| sizeof(struct i2c_hid_desc)); |
| if (ret) { |
| dev_err(&client->dev, "hid_descr_cmd failed\n"); |
| return -ENODEV; |
| } |
| |
| /* Validate the length of HID descriptor, the 4 first bytes: |
| * bytes 0-1 -> length |
| * bytes 2-3 -> bcdVersion (has to be 1.00) */ |
| /* check bcdVersion == 1.0 */ |
| if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) { |
| dev_err(&client->dev, |
| "unexpected HID descriptor bcdVersion (0x%04hx)\n", |
| le16_to_cpu(hdesc->bcdVersion)); |
| return -ENODEV; |
| } |
| |
| /* Descriptor length should be 30 bytes as per the specification */ |
| dsize = le16_to_cpu(hdesc->wHIDDescLength); |
| if (dsize != sizeof(struct i2c_hid_desc)) { |
| dev_err(&client->dev, "weird size of HID descriptor (%u)\n", |
| dsize); |
| return -ENODEV; |
| } |
| i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer); |
| return 0; |
| } |
| |
| #ifdef CONFIG_ACPI |
| |
| /* Default GPIO mapping */ |
| static const struct acpi_gpio_params i2c_hid_irq_gpio = { 0, 0, true }; |
| static const struct acpi_gpio_mapping i2c_hid_acpi_gpios[] = { |
| { "gpios", &i2c_hid_irq_gpio, 1 }, |
| { }, |
| }; |
| |
| static int i2c_hid_acpi_pdata(struct i2c_client *client, |
| struct i2c_hid_platform_data *pdata) |
| { |
| static u8 i2c_hid_guid[] = { |
| 0xF7, 0xF6, 0xDF, 0x3C, 0x67, 0x42, 0x55, 0x45, |
| 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE, |
| }; |
| union acpi_object *obj; |
| struct acpi_device *adev; |
| acpi_handle handle; |
| int ret; |
| |
| handle = ACPI_HANDLE(&client->dev); |
| if (!handle || acpi_bus_get_device(handle, &adev)) |
| return -ENODEV; |
| |
| obj = acpi_evaluate_dsm_typed(handle, i2c_hid_guid, 1, 1, NULL, |
| ACPI_TYPE_INTEGER); |
| if (!obj) { |
| dev_err(&client->dev, "device _DSM execution failed\n"); |
| return -ENODEV; |
| } |
| |
| pdata->hid_descriptor_address = obj->integer.value; |
| ACPI_FREE(obj); |
| |
| /* GPIOs are optional */ |
| ret = acpi_dev_add_driver_gpios(adev, i2c_hid_acpi_gpios); |
| return ret < 0 && ret != -ENXIO ? ret : 0; |
| } |
| |
| static const struct acpi_device_id i2c_hid_acpi_match[] = { |
| {"ACPI0C50", 0 }, |
| {"PNP0C50", 0 }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match); |
| #else |
| static inline int i2c_hid_acpi_pdata(struct i2c_client *client, |
| struct i2c_hid_platform_data *pdata) |
| { |
| return -ENODEV; |
| } |
| #endif |
| |
| #ifdef CONFIG_OF |
| static int i2c_hid_of_probe(struct i2c_client *client, |
| struct i2c_hid_platform_data *pdata) |
| { |
| struct device *dev = &client->dev; |
| u32 val; |
| int ret; |
| |
| ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val); |
| if (ret) { |
| dev_err(&client->dev, "HID register address not provided\n"); |
| return -ENODEV; |
| } |
| if (val >> 16) { |
| dev_err(&client->dev, "Bad HID register address: 0x%08x\n", |
| val); |
| return -EINVAL; |
| } |
| pdata->hid_descriptor_address = val; |
| |
| return 0; |
| } |
| |
| static const struct of_device_id i2c_hid_of_match[] = { |
| { .compatible = "hid-over-i2c" }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, i2c_hid_of_match); |
| #else |
| static inline int i2c_hid_of_probe(struct i2c_client *client, |
| struct i2c_hid_platform_data *pdata) |
| { |
| return -ENODEV; |
| } |
| #endif |
| |
| static int 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); |
| |
| ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL); |
| if (!ihid) |
| return -ENOMEM; |
| |
| if (client->dev.of_node) { |
| ret = i2c_hid_of_probe(client, &ihid->pdata); |
| if (ret) |
| goto err; |
| } else if (!platform_data) { |
| ret = i2c_hid_acpi_pdata(client, &ihid->pdata); |
| if (ret) { |
| dev_err(&client->dev, |
| "HID register address not provided\n"); |
| goto err; |
| } |
| } else { |
| ihid->pdata = *platform_data; |
| } |
| |
| if (client->irq > 0) { |
| ihid->irq = client->irq; |
| } else if (ACPI_COMPANION(&client->dev)) { |
| ihid->desc = gpiod_get(&client->dev, NULL, GPIOD_IN); |
| if (IS_ERR(ihid->desc)) { |
| dev_err(&client->dev, "Failed to get GPIO interrupt\n"); |
| return PTR_ERR(ihid->desc); |
| } |
| |
| ihid->irq = gpiod_to_irq(ihid->desc); |
| if (ihid->irq < 0) { |
| gpiod_put(ihid->desc); |
| dev_err(&client->dev, "Failed to convert GPIO to IRQ\n"); |
| return ihid->irq; |
| } |
| } |
| |
| i2c_set_clientdata(client, ihid); |
| |
| ihid->client = client; |
| |
| hidRegister = ihid->pdata.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. */ |
| ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE); |
| if (ret < 0) |
| goto err; |
| |
| pm_runtime_get_noresume(&client->dev); |
| pm_runtime_set_active(&client->dev); |
| pm_runtime_enable(&client->dev); |
| |
| ret = i2c_hid_fetch_hid_descriptor(ihid); |
| if (ret < 0) |
| goto err_pm; |
| |
| ret = i2c_hid_init_irq(client); |
| if (ret < 0) |
| goto err_pm; |
| |
| hid = hid_allocate_device(); |
| if (IS_ERR(hid)) { |
| ret = PTR_ERR(hid); |
| goto err_irq; |
| } |
| |
| ihid->hid = hid; |
| |
| hid->driver_data = client; |
| hid->ll_driver = &i2c_hid_ll_driver; |
| 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 %04hX:%04hX", |
| client->name, hid->vendor, hid->product); |
| strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys)); |
| |
| 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; |
| } |
| |
| pm_runtime_put(&client->dev); |
| return 0; |
| |
| err_mem_free: |
| hid_destroy_device(hid); |
| |
| err_irq: |
| free_irq(ihid->irq, ihid); |
| |
| err_pm: |
| pm_runtime_put_noidle(&client->dev); |
| pm_runtime_disable(&client->dev); |
| |
| err: |
| if (ihid->desc) |
| gpiod_put(ihid->desc); |
| |
| i2c_hid_free_buffers(ihid); |
| kfree(ihid); |
| return ret; |
| } |
| |
| static int i2c_hid_remove(struct i2c_client *client) |
| { |
| struct i2c_hid *ihid = i2c_get_clientdata(client); |
| struct hid_device *hid; |
| |
| pm_runtime_get_sync(&client->dev); |
| pm_runtime_disable(&client->dev); |
| pm_runtime_set_suspended(&client->dev); |
| pm_runtime_put_noidle(&client->dev); |
| |
| hid = ihid->hid; |
| hid_destroy_device(hid); |
| |
| free_irq(ihid->irq, ihid); |
| |
| if (ihid->bufsize) |
| i2c_hid_free_buffers(ihid); |
| |
| if (ihid->desc) |
| gpiod_put(ihid->desc); |
| |
| kfree(ihid); |
| |
| acpi_dev_remove_driver_gpios(ACPI_COMPANION(&client->dev)); |
| |
| 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); |
| struct hid_device *hid = ihid->hid; |
| int ret = 0; |
| int wake_status; |
| |
| if (hid->driver && hid->driver->suspend) |
| ret = hid->driver->suspend(hid, PMSG_SUSPEND); |
| |
| disable_irq(ihid->irq); |
| if (device_may_wakeup(&client->dev)) { |
| wake_status = enable_irq_wake(ihid->irq); |
| if (!wake_status) |
| ihid->irq_wake_enabled = true; |
| else |
| hid_warn(hid, "Failed to enable irq wake: %d\n", |
| wake_status); |
| } |
| |
| /* Save some power */ |
| i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); |
| |
| return ret; |
| } |
| |
| static int i2c_hid_resume(struct device *dev) |
| { |
| int ret; |
| struct i2c_client *client = to_i2c_client(dev); |
| struct i2c_hid *ihid = i2c_get_clientdata(client); |
| struct hid_device *hid = ihid->hid; |
| int wake_status; |
| |
| enable_irq(ihid->irq); |
| ret = i2c_hid_hwreset(client); |
| if (ret) |
| return ret; |
| |
| if (device_may_wakeup(&client->dev) && ihid->irq_wake_enabled) { |
| wake_status = disable_irq_wake(ihid->irq); |
| if (!wake_status) |
| ihid->irq_wake_enabled = false; |
| else |
| hid_warn(hid, "Failed to disable irq wake: %d\n", |
| wake_status); |
| } |
| |
| if (hid->driver && hid->driver->reset_resume) { |
| ret = hid->driver->reset_resume(hid); |
| return ret; |
| } |
| |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_PM |
| static int i2c_hid_runtime_suspend(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct i2c_hid *ihid = i2c_get_clientdata(client); |
| |
| i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); |
| disable_irq(ihid->irq); |
| return 0; |
| } |
| |
| static int i2c_hid_runtime_resume(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct i2c_hid *ihid = i2c_get_clientdata(client); |
| |
| enable_irq(ihid->irq); |
| i2c_hid_set_power(client, I2C_HID_PWR_ON); |
| return 0; |
| } |
| #endif |
| |
| static const struct dev_pm_ops i2c_hid_pm = { |
| SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume) |
| SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume, |
| NULL) |
| }; |
| |
| static const struct i2c_device_id i2c_hid_id_table[] = { |
| { "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, |
| .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match), |
| .of_match_table = of_match_ptr(i2c_hid_of_match), |
| }, |
| |
| .probe = i2c_hid_probe, |
| .remove = 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"); |