blob: 06d40b3d2c6afc9e5d4807e220f2c0f48fef84e1 [file] [log] [blame]
/*
* Elan Microelectronics touch panels with I2C interface
*
* Copyright (C) 2014 Elan Microelectronics Corporation.
* Scott Liu <scott.liu@emc.com.tw>
*
* This code is partly based on hid-multitouch.c:
*
* Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
* Copyright (c) 2010-2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
* Copyright (c) 2010-2012 Ecole Nationale de l'Aviation Civile, France
*
*
* This code is partly based on i2c-hid.c:
*
* 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 software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*/
#include <linux/module.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/async.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/firmware.h>
#include <linux/input/mt.h>
#include <linux/acpi.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <asm/unaligned.h>
/* Device, Driver information */
#define DEVICE_NAME "elants_i2c"
#define DRV_VERSION "1.0.9"
/* Convert from rows or columns into resolution */
#define ELAN_TS_RESOLUTION(n, m) (((n) - 1) * (m))
/* FW header data */
#define HEADER_SIZE 4
#define FW_HDR_TYPE 0
#define FW_HDR_COUNT 1
#define FW_HDR_LENGTH 2
/* Buffer mode Queue Header information */
#define QUEUE_HEADER_SINGLE 0x62
#define QUEUE_HEADER_NORMAL 0X63
#define QUEUE_HEADER_WAIT 0x64
/* Command header definition */
#define CMD_HEADER_WRITE 0x54
#define CMD_HEADER_READ 0x53
#define CMD_HEADER_6B_READ 0x5B
#define CMD_HEADER_RESP 0x52
#define CMD_HEADER_6B_RESP 0x9B
#define CMD_HEADER_HELLO 0x55
#define CMD_HEADER_REK 0x66
/* FW position data */
#define PACKET_SIZE 55
#define MAX_CONTACT_NUM 10
#define FW_POS_HEADER 0
#define FW_POS_STATE 1
#define FW_POS_TOTAL 2
#define FW_POS_XY 3
#define FW_POS_CHECKSUM 34
#define FW_POS_WIDTH 35
#define FW_POS_PRESSURE 45
#define HEADER_REPORT_10_FINGER 0x62
/* Header (4 bytes) plus 3 fill 10-finger packets */
#define MAX_PACKET_SIZE 169
#define BOOT_TIME_DELAY_MS 50
/* FW read command, 0x53 0x?? 0x0, 0x01 */
#define E_ELAN_INFO_FW_VER 0x00
#define E_ELAN_INFO_BC_VER 0x10
#define E_ELAN_INFO_TEST_VER 0xE0
#define E_ELAN_INFO_FW_ID 0xF0
#define E_INFO_OSR 0xD6
#define E_INFO_PHY_SCAN 0xD7
#define E_INFO_PHY_DRIVER 0xD8
#define MAX_RETRIES 3
#define MAX_FW_UPDATE_RETRIES 30
#define ELAN_FW_PAGESIZE 132
/* calibration timeout definition */
#define ELAN_CALI_TIMEOUT_MSEC 12000
#define ELAN_POWERON_DELAY_USEC 500
#define ELAN_RESET_DELAY_MSEC 20
enum elants_state {
ELAN_STATE_NORMAL,
ELAN_WAIT_QUEUE_HEADER,
ELAN_WAIT_RECALIBRATION,
};
enum elants_iap_mode {
ELAN_IAP_OPERATIONAL,
ELAN_IAP_RECOVERY,
};
/* struct elants_data - represents state of Elan touchscreen device */
struct elants_data {
struct i2c_client *client;
struct input_dev *input;
struct regulator *vcc33;
struct regulator *vccio;
struct gpio_desc *reset_gpio;
u16 fw_version;
u8 test_version;
u8 solution_version;
u8 bc_version;
u8 iap_version;
u16 hw_version;
unsigned int x_res; /* resolution in units/mm */
unsigned int y_res;
unsigned int x_max;
unsigned int y_max;
enum elants_state state;
enum elants_iap_mode iap_mode;
/* Guards against concurrent access to the device via sysfs */
struct mutex sysfs_mutex;
u8 cmd_resp[HEADER_SIZE];
struct completion cmd_done;
u8 buf[MAX_PACKET_SIZE];
bool wake_irq_enabled;
bool keep_power_in_suspend;
bool unbinding;
};
static int elants_i2c_send(struct i2c_client *client,
const void *data, size_t size)
{
int ret;
ret = i2c_master_send(client, data, size);
if (ret == size)
return 0;
if (ret >= 0)
ret = -EIO;
dev_err(&client->dev, "%s failed (%*ph): %d\n",
__func__, (int)size, data, ret);
return ret;
}
static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
{
int ret;
ret = i2c_master_recv(client, data, size);
if (ret == size)
return 0;
if (ret >= 0)
ret = -EIO;
dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
return ret;
}
static int elants_i2c_execute_command(struct i2c_client *client,
const u8 *cmd, size_t cmd_size,
u8 *resp, size_t resp_size)
{
struct i2c_msg msgs[2];
int ret;
u8 expected_response;
switch (cmd[0]) {
case CMD_HEADER_READ:
expected_response = CMD_HEADER_RESP;
break;
case CMD_HEADER_6B_READ:
expected_response = CMD_HEADER_6B_RESP;
break;
default:
dev_err(&client->dev, "%s: invalid command %*ph\n",
__func__, (int)cmd_size, cmd);
return -EINVAL;
}
msgs[0].addr = client->addr;
msgs[0].flags = client->flags & I2C_M_TEN;
msgs[0].len = cmd_size;
msgs[0].buf = (u8 *)cmd;
msgs[1].addr = client->addr;
msgs[1].flags = client->flags & I2C_M_TEN;
msgs[1].flags |= I2C_M_RD;
msgs[1].len = resp_size;
msgs[1].buf = resp;
ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
if (ret < 0)
return ret;
if (ret != ARRAY_SIZE(msgs) || resp[FW_HDR_TYPE] != expected_response)
return -EIO;
return 0;
}
static int elants_i2c_calibrate(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
int ret, error;
static const u8 w_flashkey[] = { 0x54, 0xC0, 0xE1, 0x5A };
static const u8 rek[] = { 0x54, 0x29, 0x00, 0x01 };
static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
disable_irq(client->irq);
ts->state = ELAN_WAIT_RECALIBRATION;
reinit_completion(&ts->cmd_done);
elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
elants_i2c_send(client, rek, sizeof(rek));
enable_irq(client->irq);
ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
ts->state = ELAN_STATE_NORMAL;
if (ret <= 0) {
error = ret < 0 ? ret : -ETIMEDOUT;
dev_err(&client->dev,
"error while waiting for calibration to complete: %d\n",
error);
return error;
}
if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
dev_err(&client->dev,
"unexpected calibration response: %*ph\n",
(int)sizeof(ts->cmd_resp), ts->cmd_resp);
return -EINVAL;
}
return 0;
}
static int elants_i2c_sw_reset(struct i2c_client *client)
{
const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
int error;
error = elants_i2c_send(client, soft_rst_cmd,
sizeof(soft_rst_cmd));
if (error) {
dev_err(&client->dev, "software reset failed: %d\n", error);
return error;
}
/*
* We should wait at least 10 msec (but no more than 40) before
* sending fastboot or IAP command to the device.
*/
msleep(30);
return 0;
}
static u16 elants_i2c_parse_version(u8 *buf)
{
return get_unaligned_be32(buf) >> 4;
}
static int elants_i2c_query_hw_version(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
int error, retry_cnt;
const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
u8 resp[HEADER_SIZE];
for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
resp, sizeof(resp));
if (!error) {
ts->hw_version = elants_i2c_parse_version(resp);
if (ts->hw_version != 0xffff)
return 0;
}
dev_dbg(&client->dev, "read fw id error=%d, buf=%*phC\n",
error, (int)sizeof(resp), resp);
}
if (error) {
dev_err(&client->dev,
"Failed to read fw id: %d\n", error);
return error;
}
dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
return -EINVAL;
}
static int elants_i2c_query_fw_version(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
int error, retry_cnt;
const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
u8 resp[HEADER_SIZE];
for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
resp, sizeof(resp));
if (!error) {
ts->fw_version = elants_i2c_parse_version(resp);
if (ts->fw_version != 0x0000 &&
ts->fw_version != 0xffff)
return 0;
}
dev_dbg(&client->dev, "read fw version error=%d, buf=%*phC\n",
error, (int)sizeof(resp), resp);
}
dev_err(&client->dev,
"Failed to read fw version or fw version is invalid\n");
return -EINVAL;
}
static int elants_i2c_query_test_version(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
int error, retry_cnt;
u16 version;
const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
u8 resp[HEADER_SIZE];
for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
resp, sizeof(resp));
if (!error) {
version = elants_i2c_parse_version(resp);
ts->test_version = version >> 8;
ts->solution_version = version & 0xff;
return 0;
}
dev_dbg(&client->dev,
"read test version error rc=%d, buf=%*phC\n",
error, (int)sizeof(resp), resp);
}
dev_err(&client->dev, "Failed to read test version\n");
return -EINVAL;
}
static int elants_i2c_query_bc_version(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
u8 resp[HEADER_SIZE];
u16 version;
int error;
error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
resp, sizeof(resp));
if (error) {
dev_err(&client->dev,
"read BC version error=%d, buf=%*phC\n",
error, (int)sizeof(resp), resp);
return error;
}
version = elants_i2c_parse_version(resp);
ts->bc_version = version >> 8;
ts->iap_version = version & 0xff;
return 0;
}
static int elants_i2c_query_ts_info(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
int error;
u8 resp[17];
u16 phy_x, phy_y, rows, cols, osr;
const u8 get_resolution_cmd[] = {
CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
};
const u8 get_osr_cmd[] = {
CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
};
const u8 get_physical_scan_cmd[] = {
CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
};
const u8 get_physical_drive_cmd[] = {
CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
};
/* Get trace number */
error = elants_i2c_execute_command(client,
get_resolution_cmd,
sizeof(get_resolution_cmd),
resp, sizeof(resp));
if (error) {
dev_err(&client->dev, "get resolution command failed: %d\n",
error);
return error;
}
rows = resp[2] + resp[6] + resp[10];
cols = resp[3] + resp[7] + resp[11];
/* Process mm_to_pixel information */
error = elants_i2c_execute_command(client,
get_osr_cmd, sizeof(get_osr_cmd),
resp, sizeof(resp));
if (error) {
dev_err(&client->dev, "get osr command failed: %d\n",
error);
return error;
}
osr = resp[3];
error = elants_i2c_execute_command(client,
get_physical_scan_cmd,
sizeof(get_physical_scan_cmd),
resp, sizeof(resp));
if (error) {
dev_err(&client->dev, "get physical scan command failed: %d\n",
error);
return error;
}
phy_x = get_unaligned_be16(&resp[2]);
error = elants_i2c_execute_command(client,
get_physical_drive_cmd,
sizeof(get_physical_drive_cmd),
resp, sizeof(resp));
if (error) {
dev_err(&client->dev, "get physical drive command failed: %d\n",
error);
return error;
}
phy_y = get_unaligned_be16(&resp[2]);
dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
if (rows == 0 || cols == 0 || osr == 0) {
dev_warn(&client->dev,
"invalid trace number data: %d, %d, %d\n",
rows, cols, osr);
} else {
/* translate trace number to TS resolution */
ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
}
return 0;
}
static int elants_i2c_fastboot(struct i2c_client *client)
{
const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
int error;
error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
if (error) {
dev_err(&client->dev, "boot failed: %d\n", error);
return error;
}
dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
return 0;
}
static int elants_i2c_initialize(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
int error, error2, retry_cnt;
const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
u8 buf[HEADER_SIZE];
for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
error = elants_i2c_sw_reset(client);
if (error) {
/* Continue initializing if it's the last try */
if (retry_cnt < MAX_RETRIES - 1)
continue;
}
error = elants_i2c_fastboot(client);
if (error) {
/* Continue initializing if it's the last try */
if (retry_cnt < MAX_RETRIES - 1)
continue;
}
/* Wait for Hello packet */
msleep(BOOT_TIME_DELAY_MS);
error = elants_i2c_read(client, buf, sizeof(buf));
if (error) {
dev_err(&client->dev,
"failed to read 'hello' packet: %d\n", error);
} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
ts->iap_mode = ELAN_IAP_OPERATIONAL;
break;
} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
/*
* Setting error code will mark device
* in recovery mode below.
*/
error = -EIO;
break;
} else {
error = -EINVAL;
dev_err(&client->dev,
"invalid 'hello' packet: %*ph\n",
(int)sizeof(buf), buf);
}
}
/* hw version is available even if device in recovery state */
error2 = elants_i2c_query_hw_version(ts);
if (!error)
error = error2;
if (!error)
error = elants_i2c_query_fw_version(ts);
if (!error)
error = elants_i2c_query_test_version(ts);
if (!error)
error = elants_i2c_query_bc_version(ts);
if (!error)
error = elants_i2c_query_ts_info(ts);
if (error)
ts->iap_mode = ELAN_IAP_RECOVERY;
return 0;
}
/*
* Firmware update interface.
*/
static int elants_i2c_fw_write_page(struct i2c_client *client,
const void *page)
{
const u8 ack_ok[] = { 0xaa, 0xaa };
u8 buf[2];
int retry;
int error;
for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
if (error) {
dev_err(&client->dev,
"IAP Write Page failed: %d\n", error);
continue;
}
error = elants_i2c_read(client, buf, 2);
if (error) {
dev_err(&client->dev,
"IAP Ack read failed: %d\n", error);
return error;
}
if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
return 0;
error = -EIO;
dev_err(&client->dev,
"IAP Get Ack Error [%02x:%02x]\n",
buf[0], buf[1]);
}
return error;
}
static int elants_i2c_do_update_firmware(struct i2c_client *client,
const struct firmware *fw,
bool force)
{
const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
const u8 close_idle[] = {0x54, 0x2c, 0x01, 0x01};
u8 buf[HEADER_SIZE];
u16 send_id;
int page, n_fw_pages;
int error;
/* Recovery mode detection! */
if (force) {
dev_dbg(&client->dev, "Recovery mode procedure\n");
error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
} else {
/* Start IAP Procedure */
dev_dbg(&client->dev, "Normal IAP procedure\n");
/* Close idle mode */
error = elants_i2c_send(client, close_idle, sizeof(close_idle));
if (error)
dev_err(&client->dev, "Failed close idle: %d\n", error);
msleep(60);
elants_i2c_sw_reset(client);
msleep(20);
error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
}
if (error) {
dev_err(&client->dev, "failed to enter IAP mode: %d\n", error);
return error;
}
msleep(20);
/* check IAP state */
error = elants_i2c_read(client, buf, 4);
if (error) {
dev_err(&client->dev,
"failed to read IAP acknowledgement: %d\n",
error);
return error;
}
if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
dev_err(&client->dev,
"failed to enter IAP: %*ph (expected %*ph)\n",
(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
return -EIO;
}
dev_info(&client->dev, "successfully entered IAP mode");
send_id = client->addr;
error = elants_i2c_send(client, &send_id, 1);
if (error) {
dev_err(&client->dev, "sending dummy byte failed: %d\n",
error);
return error;
}
/* Clear the last page of Master */
error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
if (error) {
dev_err(&client->dev, "clearing of the last page failed: %d\n",
error);
return error;
}
error = elants_i2c_read(client, buf, 2);
if (error) {
dev_err(&client->dev,
"failed to read ACK for clearing the last page: %d\n",
error);
return error;
}
n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
for (page = 0; page < n_fw_pages; page++) {
error = elants_i2c_fw_write_page(client,
fw->data + page * ELAN_FW_PAGESIZE);
if (error) {
dev_err(&client->dev,
"failed to write FW page %d: %d\n",
page, error);
return error;
}
}
/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
msleep(300);
dev_info(&client->dev, "firmware update completed\n");
return 0;
}
static int elants_i2c_fw_update(struct elants_data *ts)
{
struct i2c_client *client = ts->client;
const struct firmware *fw;
char *fw_name;
int error;
fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
if (!fw_name)
return -ENOMEM;
dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
error = request_firmware(&fw, fw_name, &client->dev);
kfree(fw_name);
if (error) {
dev_info(&client->dev, "failed to request firmware: %d\n",
error);
dev_info(&client->dev, "Falling back to 'elants_i2c.bin' instead\n");
error = request_firmware(&fw, "elants_i2c.bin", &client->dev);
if (error) {
dev_info(&client->dev, "failed to request firmware: %d\n",
error);
return error;
}
}
if (fw->size % ELAN_FW_PAGESIZE) {
dev_err(&client->dev, "invalid firmware length: %zu\n",
fw->size);
error = -EINVAL;
goto out;
}
disable_irq(client->irq);
error = elants_i2c_do_update_firmware(client, fw,
ts->iap_mode == ELAN_IAP_RECOVERY);
if (error) {
dev_err(&client->dev, "firmware update failed: %d\n", error);
ts->iap_mode = ELAN_IAP_RECOVERY;
goto out_enable_irq;
}
error = elants_i2c_initialize(ts);
if (error) {
dev_err(&client->dev,
"failed to initialize device after firmware update: %d\n",
error);
ts->iap_mode = ELAN_IAP_RECOVERY;
goto out_enable_irq;
}
ts->iap_mode = ELAN_IAP_OPERATIONAL;
out_enable_irq:
ts->state = ELAN_STATE_NORMAL;
enable_irq(client->irq);
msleep(100);
if (!error)
elants_i2c_calibrate(ts);
out:
release_firmware(fw);
return error;
}
/*
* Event reporting.
*/
static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf)
{
struct input_dev *input = ts->input;
unsigned int n_fingers;
u16 finger_state;
int i;
n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
buf[FW_POS_STATE];
dev_dbg(&ts->client->dev,
"n_fingers: %u, state: %04x\n", n_fingers, finger_state);
for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
if (finger_state & 1) {
unsigned int x, y, p, w;
u8 *pos;
pos = &buf[FW_POS_XY + i * 3];
x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
p = buf[FW_POS_PRESSURE + i];
w = buf[FW_POS_WIDTH + i];
dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
i, x, y, p, w);
input_mt_slot(input, i);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
input_event(input, EV_ABS, ABS_MT_POSITION_X, x);
input_event(input, EV_ABS, ABS_MT_POSITION_Y, y);
input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
n_fingers--;
}
finger_state >>= 1;
}
input_mt_sync_frame(input);
input_sync(input);
}
static u8 elants_i2c_calculate_checksum(u8 *buf)
{
u8 checksum = 0;
u8 i;
for (i = 0; i < FW_POS_CHECKSUM; i++)
checksum += buf[i];
return checksum;
}
static void elants_i2c_event(struct elants_data *ts, u8 *buf)
{
u8 checksum = elants_i2c_calculate_checksum(buf);
if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
dev_warn(&ts->client->dev,
"%s: invalid checksum for packet %02x: %02x vs. %02x\n",
__func__, buf[FW_POS_HEADER],
checksum, buf[FW_POS_CHECKSUM]);
else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
dev_warn(&ts->client->dev,
"%s: unknown packet type: %02x\n",
__func__, buf[FW_POS_HEADER]);
else
elants_i2c_mt_event(ts, buf);
}
static irqreturn_t elants_i2c_irq(int irq, void *_dev)
{
const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
struct elants_data *ts = _dev;
struct i2c_client *client = ts->client;
int report_count, report_len;
int i;
int len;
len = i2c_master_recv(client, ts->buf, sizeof(ts->buf));
if (len < 0) {
dev_err(&client->dev, "%s: failed to read data: %d\n",
__func__, len);
goto out;
}
dev_dbg(&client->dev, "%s: packet %*ph\n",
__func__, HEADER_SIZE, ts->buf);
switch (ts->state) {
case ELAN_WAIT_RECALIBRATION:
if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
complete(&ts->cmd_done);
ts->state = ELAN_STATE_NORMAL;
}
break;
case ELAN_WAIT_QUEUE_HEADER:
if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
break;
ts->state = ELAN_STATE_NORMAL;
/* fall through */
case ELAN_STATE_NORMAL:
switch (ts->buf[FW_HDR_TYPE]) {
case CMD_HEADER_HELLO:
case CMD_HEADER_RESP:
case CMD_HEADER_REK:
break;
case QUEUE_HEADER_WAIT:
if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
dev_err(&client->dev,
"invalid wait packet %*ph\n",
HEADER_SIZE, ts->buf);
} else {
ts->state = ELAN_WAIT_QUEUE_HEADER;
udelay(30);
}
break;
case QUEUE_HEADER_SINGLE:
elants_i2c_event(ts, &ts->buf[HEADER_SIZE]);
break;
case QUEUE_HEADER_NORMAL:
report_count = ts->buf[FW_HDR_COUNT];
if (report_count == 0 || report_count > 3) {
dev_err(&client->dev,
"bad report count: %*ph\n",
HEADER_SIZE, ts->buf);
break;
}
report_len = ts->buf[FW_HDR_LENGTH] / report_count;
if (report_len != PACKET_SIZE) {
dev_err(&client->dev,
"mismatching report length: %*ph\n",
HEADER_SIZE, ts->buf);
break;
}
for (i = 0; i < report_count; i++) {
u8 *buf = ts->buf + HEADER_SIZE +
i * PACKET_SIZE;
elants_i2c_event(ts, buf);
}
break;
default:
dev_err(&client->dev, "unknown packet %*ph\n",
HEADER_SIZE, ts->buf);
break;
}
break;
}
out:
return IRQ_HANDLED;
}
/*
* sysfs interface
*/
static ssize_t calibrate_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct elants_data *ts = i2c_get_clientdata(client);
int error;
error = mutex_lock_interruptible(&ts->sysfs_mutex);
if (error)
return error;
error = elants_i2c_calibrate(ts);
mutex_unlock(&ts->sysfs_mutex);
return error ?: count;
}
static ssize_t write_update_fw(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct elants_data *ts = i2c_get_clientdata(client);
int error;
error = mutex_lock_interruptible(&ts->sysfs_mutex);
if (error)
return error;
error = elants_i2c_fw_update(ts);
dev_dbg(dev, "firmware update result: %d\n", error);
mutex_unlock(&ts->sysfs_mutex);
return error ?: count;
}
static ssize_t show_iap_mode(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct elants_data *ts = i2c_get_clientdata(client);
return sprintf(buf, "%s\n",
ts->iap_mode == ELAN_IAP_OPERATIONAL ?
"Normal" : "Recovery");
}
static DEVICE_ATTR(calibrate, S_IWUSR, NULL, calibrate_store);
static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
struct elants_version_attribute {
struct device_attribute dattr;
size_t field_offset;
size_t field_size;
};
#define __ELANTS_FIELD_SIZE(_field) \
sizeof(((struct elants_data *)NULL)->_field)
#define __ELANTS_VERIFY_SIZE(_field) \
(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) + \
__ELANTS_FIELD_SIZE(_field))
#define ELANTS_VERSION_ATTR(_field) \
struct elants_version_attribute elants_ver_attr_##_field = { \
.dattr = __ATTR(_field, S_IRUGO, \
elants_version_attribute_show, NULL), \
.field_offset = offsetof(struct elants_data, _field), \
.field_size = __ELANTS_VERIFY_SIZE(_field), \
}
static ssize_t elants_version_attribute_show(struct device *dev,
struct device_attribute *dattr,
char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct elants_data *ts = i2c_get_clientdata(client);
struct elants_version_attribute *attr =
container_of(dattr, struct elants_version_attribute, dattr);
u8 *field = (u8 *)((char *)ts + attr->field_offset);
unsigned int fmt_size;
unsigned int val;
if (attr->field_size == 1) {
val = *field;
fmt_size = 2; /* 2 HEX digits */
} else {
val = *(u16 *)field;
fmt_size = 4; /* 4 HEX digits */
}
return sprintf(buf, "%0*x\n", fmt_size, val);
}
static ELANTS_VERSION_ATTR(fw_version);
static ELANTS_VERSION_ATTR(hw_version);
static ELANTS_VERSION_ATTR(test_version);
static ELANTS_VERSION_ATTR(solution_version);
static ELANTS_VERSION_ATTR(bc_version);
static ELANTS_VERSION_ATTR(iap_version);
static struct attribute *elants_attributes[] = {
&dev_attr_calibrate.attr,
&dev_attr_update_fw.attr,
&dev_attr_iap_mode.attr,
&elants_ver_attr_fw_version.dattr.attr,
&elants_ver_attr_hw_version.dattr.attr,
&elants_ver_attr_test_version.dattr.attr,
&elants_ver_attr_solution_version.dattr.attr,
&elants_ver_attr_bc_version.dattr.attr,
&elants_ver_attr_iap_version.dattr.attr,
NULL
};
static struct attribute_group elants_attribute_group = {
.attrs = elants_attributes,
};
static void elants_i2c_remove_sysfs_group(void *_data)
{
struct elants_data *ts = _data;
sysfs_remove_group(&ts->client->dev.kobj, &elants_attribute_group);
}
static int elants_i2c_power_on(struct elants_data *ts)
{
int error;
/*
* If we do not have reset gpio assume platform firmware
* controls regulators and does power them on for us.
*/
if (IS_ERR_OR_NULL(ts->reset_gpio))
return 0;
gpiod_set_value_cansleep(ts->reset_gpio, 1);
error = regulator_enable(ts->vcc33);
if (error) {
dev_err(&ts->client->dev,
"failed to enable vcc33 regulator: %d\n",
error);
goto release_reset_gpio;
}
error = regulator_enable(ts->vccio);
if (error) {
dev_err(&ts->client->dev,
"failed to enable vccio regulator: %d\n",
error);
regulator_disable(ts->vcc33);
goto release_reset_gpio;
}
/*
* We need to wait a bit after powering on controller before
* we are allowed to release reset GPIO.
*/
udelay(ELAN_POWERON_DELAY_USEC);
release_reset_gpio:
gpiod_set_value_cansleep(ts->reset_gpio, 0);
if (error)
return error;
msleep(ELAN_RESET_DELAY_MSEC);
return 0;
}
static void elants_i2c_power_off(void *_data)
{
struct elants_data *ts = _data;
if (ts->unbinding) {
dev_info(&ts->client->dev,
"Not disabling regulators to continue allowing userspace i2c-dev access\n");
return;
}
if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
/*
* Activate reset gpio to prevent leakage through the
* pin once we shut off power to the controller.
*/
gpiod_set_value_cansleep(ts->reset_gpio, 1);
regulator_disable(ts->vccio);
regulator_disable(ts->vcc33);
}
}
static int elants_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
union i2c_smbus_data dummy;
struct elants_data *ts;
unsigned long irqflags;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev,
"%s: i2c check functionality error\n", DEVICE_NAME);
return -ENXIO;
}
ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
if (!ts)
return -ENOMEM;
mutex_init(&ts->sysfs_mutex);
init_completion(&ts->cmd_done);
ts->client = client;
i2c_set_clientdata(client, ts);
ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
if (IS_ERR(ts->vcc33)) {
error = PTR_ERR(ts->vcc33);
if (error != -EPROBE_DEFER)
dev_err(&client->dev,
"Failed to get 'vcc33' regulator: %d\n",
error);
return error;
}
ts->vccio = devm_regulator_get(&client->dev, "vccio");
if (IS_ERR(ts->vccio)) {
error = PTR_ERR(ts->vccio);
if (error != -EPROBE_DEFER)
dev_err(&client->dev,
"Failed to get 'vccio' regulator: %d\n",
error);
return error;
}
ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(ts->reset_gpio)) {
error = PTR_ERR(ts->reset_gpio);
if (error == -EPROBE_DEFER)
return error;
if (error != -ENOENT && error != -ENOSYS) {
dev_err(&client->dev,
"failed to get reset gpio: %d\n",
error);
return error;
}
ts->keep_power_in_suspend = true;
}
error = elants_i2c_power_on(ts);
if (error)
return error;
error = devm_add_action(&client->dev, elants_i2c_power_off, ts);
if (error) {
dev_err(&client->dev,
"failed to install power off action: %d\n", error);
elants_i2c_power_off(ts);
return error;
}
/* Make sure there is something at this address */
if (i2c_smbus_xfer(client->adapter, client->addr, 0,
I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
dev_err(&client->dev, "nothing at this address\n");
return -ENXIO;
}
error = elants_i2c_initialize(ts);
if (error) {
dev_err(&client->dev, "failed to initialize: %d\n", error);
return error;
}
ts->input = devm_input_allocate_device(&client->dev);
if (!ts->input) {
dev_err(&client->dev, "Failed to allocate input device\n");
return -ENOMEM;
}
ts->input->name = "Elan Touchscreen";
ts->input->id.bustype = BUS_I2C;
__set_bit(BTN_TOUCH, ts->input->keybit);
__set_bit(EV_ABS, ts->input->evbit);
__set_bit(EV_KEY, ts->input->evbit);
/* Single touch input params setup */
input_set_abs_params(ts->input, ABS_X, 0, ts->x_max, 0, 0);
input_set_abs_params(ts->input, ABS_Y, 0, ts->y_max, 0, 0);
input_set_abs_params(ts->input, ABS_PRESSURE, 0, 255, 0, 0);
input_abs_set_res(ts->input, ABS_X, ts->x_res);
input_abs_set_res(ts->input, ABS_Y, ts->y_res);
/* Multitouch input params setup */
error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(&client->dev,
"failed to initialize MT slots: %d\n", error);
return error;
}
input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
input_set_drvdata(ts->input, ts);
error = input_register_device(ts->input);
if (error) {
dev_err(&client->dev,
"unable to register input device: %d\n", error);
return error;
}
/*
* Systems using device tree should set up interrupt via DTS,
* the rest will use the default falling edge interrupts.
*/
irqflags = client->dev.of_node ? 0 : IRQF_TRIGGER_FALLING;
error = devm_request_threaded_irq(&client->dev, client->irq,
NULL, elants_i2c_irq,
irqflags | IRQF_ONESHOT,
client->name, ts);
if (error) {
dev_err(&client->dev, "Failed to register interrupt\n");
return error;
}
/*
* Systems using device tree should set up wakeup via DTS,
* the rest will configure device as wakeup source by default.
*/
if (!client->dev.of_node)
device_init_wakeup(&client->dev, true);
error = sysfs_create_group(&client->dev.kobj, &elants_attribute_group);
if (error) {
dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
error);
return error;
}
error = devm_add_action(&client->dev,
elants_i2c_remove_sysfs_group, ts);
if (error) {
elants_i2c_remove_sysfs_group(ts);
dev_err(&client->dev,
"Failed to add sysfs cleanup action: %d\n",
error);
return error;
}
return 0;
}
static int elants_i2c_remove(struct i2c_client *client)
{
struct elants_data *ts = i2c_get_clientdata(client);
/*
* Let elants_i2c_power_off know that it needs to keep
* regulators on.
*/
ts->unbinding = true;
return 0;
}
static int __maybe_unused elants_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct elants_data *ts = i2c_get_clientdata(client);
const u8 set_sleep_cmd[] = { 0x54, 0x50, 0x00, 0x01 };
int retry_cnt;
int error;
/* Command not support in IAP recovery mode */
if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
return -EBUSY;
disable_irq(client->irq);
if (device_may_wakeup(dev)) {
/*
* The device will automatically enter idle mode
* that has reduced power consumption.
*/
ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
} else if (ts->keep_power_in_suspend) {
for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
error = elants_i2c_send(client, set_sleep_cmd,
sizeof(set_sleep_cmd));
if (!error)
break;
dev_err(&client->dev,
"suspend command failed: %d\n", error);
}
} else {
elants_i2c_power_off(ts);
}
return 0;
}
static int __maybe_unused elants_i2c_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct elants_data *ts = i2c_get_clientdata(client);
const u8 set_active_cmd[] = { 0x54, 0x58, 0x00, 0x01 };
int retry_cnt;
int error;
if (device_may_wakeup(dev)) {
if (ts->wake_irq_enabled)
disable_irq_wake(client->irq);
elants_i2c_sw_reset(client);
} else if (ts->keep_power_in_suspend) {
for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
error = elants_i2c_send(client, set_active_cmd,
sizeof(set_active_cmd));
if (!error)
break;
dev_err(&client->dev,
"resume command failed: %d\n", error);
}
} else {
elants_i2c_power_on(ts);
elants_i2c_initialize(ts);
}
ts->state = ELAN_STATE_NORMAL;
/*
* FIXME: Clear interrupts by reading data from the chip.
* The kernel is supposed to replay edge-triggered interrupts
* when we enable them, but this does not seem to happen
* on some devices.
*/
(void) i2c_master_recv(client, ts->buf, sizeof(ts->buf));
enable_irq(client->irq);
return 0;
}
static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
elants_i2c_suspend, elants_i2c_resume);
static const struct i2c_device_id elants_i2c_id[] = {
{ DEVICE_NAME, 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
#ifdef CONFIG_ACPI
static const struct acpi_device_id elants_acpi_id[] = {
{ "ELAN0001", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
#endif
#ifdef CONFIG_OF
static const struct of_device_id elants_of_match[] = {
{ .compatible = "elan,ekth3500" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, elants_of_match);
#endif
static struct i2c_driver elants_i2c_driver = {
.probe = elants_i2c_probe,
.remove = elants_i2c_remove,
.id_table = elants_i2c_id,
.driver = {
.name = DEVICE_NAME,
.pm = &elants_i2c_pm_ops,
.acpi_match_table = ACPI_PTR(elants_acpi_id),
.of_match_table = of_match_ptr(elants_of_match),
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
module_i2c_driver(elants_i2c_driver);
MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
MODULE_VERSION(DRV_VERSION);
MODULE_LICENSE("GPL");