blob: 191d4f38d991ec52493f66d4a0b4d474d1f8df38 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Goodix Touchscreen firmware upload support
*
* Copyright (c) 2021 Hans de Goede <hdegoede@redhat.com>
*
* This is a rewrite of gt9xx_update.c from the Allwinner H3 BSP which is:
* Copyright (c) 2010 - 2012 Goodix Technology.
* Author: andrew@goodix.com
*/
#include <linux/device.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include "goodix.h"
#define GOODIX_FW_HEADER_LENGTH sizeof(struct goodix_fw_header)
#define GOODIX_FW_SECTION_LENGTH 0x2000
#define GOODIX_FW_DSP_LENGTH 0x1000
#define GOODIX_FW_UPLOAD_ADDRESS 0xc000
#define GOODIX_CFG_LOC_HAVE_KEY 7
#define GOODIX_CFG_LOC_DRVA_NUM 27
#define GOODIX_CFG_LOC_DRVB_NUM 28
#define GOODIX_CFG_LOC_SENS_NUM 29
struct goodix_fw_header {
u8 hw_info[4];
u8 pid[8];
u8 vid[2];
} __packed;
static u16 goodix_firmware_checksum(const u8 *data, int size)
{
u16 checksum = 0;
int i;
for (i = 0; i < size; i += 2)
checksum += (data[i] << 8) + data[i + 1];
return checksum;
}
static int goodix_firmware_verify(struct device *dev, const struct firmware *fw)
{
const struct goodix_fw_header *fw_header;
size_t expected_size;
const u8 *data;
u16 checksum;
char buf[9];
expected_size = GOODIX_FW_HEADER_LENGTH + 4 * GOODIX_FW_SECTION_LENGTH +
GOODIX_FW_DSP_LENGTH;
if (fw->size != expected_size) {
dev_err(dev, "Firmware has wrong size, expected %zu got %zu\n",
expected_size, fw->size);
return -EINVAL;
}
data = fw->data + GOODIX_FW_HEADER_LENGTH;
checksum = goodix_firmware_checksum(data, 4 * GOODIX_FW_SECTION_LENGTH);
if (checksum) {
dev_err(dev, "Main firmware checksum error\n");
return -EINVAL;
}
data += 4 * GOODIX_FW_SECTION_LENGTH;
checksum = goodix_firmware_checksum(data, GOODIX_FW_DSP_LENGTH);
if (checksum) {
dev_err(dev, "DSP firmware checksum error\n");
return -EINVAL;
}
fw_header = (const struct goodix_fw_header *)fw->data;
dev_info(dev, "Firmware hardware info %02x%02x%02x%02x\n",
fw_header->hw_info[0], fw_header->hw_info[1],
fw_header->hw_info[2], fw_header->hw_info[3]);
/* pid is a 8 byte buffer containing a string, weird I know */
memcpy(buf, fw_header->pid, 8);
buf[8] = 0;
dev_info(dev, "Firmware PID: %s VID: %02x%02x\n", buf,
fw_header->vid[0], fw_header->vid[1]);
return 0;
}
static int goodix_enter_upload_mode(struct i2c_client *client)
{
int tries, error;
u8 val;
tries = 200;
do {
error = goodix_i2c_write_u8(client,
GOODIX_REG_MISCTL_SWRST, 0x0c);
if (error)
return error;
error = goodix_i2c_read(client,
GOODIX_REG_MISCTL_SWRST, &val, 1);
if (error)
return error;
if (val == 0x0c)
break;
} while (--tries);
if (!tries) {
dev_err(&client->dev, "Error could not hold ss51 & dsp\n");
return -EIO;
}
/* DSP_CK and DSP_ALU_CK PowerOn */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_DSP_CTL, 0x00);
if (error)
return error;
/* Disable watchdog */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_TMR0_EN, 0x00);
if (error)
return error;
/* Clear cache enable */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_CACHE_EN, 0x00);
if (error)
return error;
/* Set boot from SRAM */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_BOOTCTL, 0x02);
if (error)
return error;
/* Software reboot */
error = goodix_i2c_write_u8(client,
GOODIX_REG_MISCTL_CPU_SWRST_PULSE, 0x01);
if (error)
return error;
/* Clear control flag */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_BOOTCTL, 0x00);
if (error)
return error;
/* Set scramble */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_BOOT_OPT, 0x00);
if (error)
return error;
/* Enable accessing code */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_MEM_CD_EN, 0x01);
if (error)
return error;
return 0;
}
static int goodix_start_firmware(struct i2c_client *client)
{
int error;
u8 val;
/* Init software watchdog */
error = goodix_i2c_write_u8(client, GOODIX_REG_SW_WDT, 0xaa);
if (error)
return error;
/* Release SS51 & DSP */
error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_SWRST, 0x00);
if (error)
return error;
error = goodix_i2c_read(client, GOODIX_REG_SW_WDT, &val, 1);
if (error)
return error;
/* The value we've written to SW_WDT should have been cleared now */
if (val == 0xaa) {
dev_err(&client->dev, "Error SW_WDT reg not cleared on fw startup\n");
return -EIO;
}
/* Re-init software watchdog */
error = goodix_i2c_write_u8(client, GOODIX_REG_SW_WDT, 0xaa);
if (error)
return error;
return 0;
}
static int goodix_firmware_upload(struct goodix_ts_data *ts)
{
const struct firmware *fw;
char fw_name[64];
const u8 *data;
int error;
snprintf(fw_name, sizeof(fw_name), "goodix/%s", ts->firmware_name);
error = request_firmware(&fw, fw_name, &ts->client->dev);
if (error) {
dev_err(&ts->client->dev, "Firmware request error %d\n", error);
return error;
}
error = goodix_firmware_verify(&ts->client->dev, fw);
if (error)
goto release;
error = goodix_reset_no_int_sync(ts);
if (error)
goto release;
error = goodix_enter_upload_mode(ts->client);
if (error)
goto release;
/* Select SRAM bank 0 and upload section 1 & 2 */
error = goodix_i2c_write_u8(ts->client,
GOODIX_REG_MISCTL_SRAM_BANK, 0x00);
if (error)
goto release;
data = fw->data + GOODIX_FW_HEADER_LENGTH;
error = goodix_i2c_write(ts->client, GOODIX_FW_UPLOAD_ADDRESS,
data, 2 * GOODIX_FW_SECTION_LENGTH);
if (error)
goto release;
/* Select SRAM bank 1 and upload section 3 & 4 */
error = goodix_i2c_write_u8(ts->client,
GOODIX_REG_MISCTL_SRAM_BANK, 0x01);
if (error)
goto release;
data += 2 * GOODIX_FW_SECTION_LENGTH;
error = goodix_i2c_write(ts->client, GOODIX_FW_UPLOAD_ADDRESS,
data, 2 * GOODIX_FW_SECTION_LENGTH);
if (error)
goto release;
/* Select SRAM bank 2 and upload the DSP firmware */
error = goodix_i2c_write_u8(ts->client,
GOODIX_REG_MISCTL_SRAM_BANK, 0x02);
if (error)
goto release;
data += 2 * GOODIX_FW_SECTION_LENGTH;
error = goodix_i2c_write(ts->client, GOODIX_FW_UPLOAD_ADDRESS,
data, GOODIX_FW_DSP_LENGTH);
if (error)
goto release;
error = goodix_start_firmware(ts->client);
if (error)
goto release;
error = goodix_int_sync(ts);
release:
release_firmware(fw);
return error;
}
static int goodix_prepare_bak_ref(struct goodix_ts_data *ts)
{
u8 have_key, driver_num, sensor_num;
if (ts->bak_ref)
return 0; /* Already done */
have_key = (ts->config[GOODIX_CFG_LOC_HAVE_KEY] & 0x01);
driver_num = (ts->config[GOODIX_CFG_LOC_DRVA_NUM] & 0x1f) +
(ts->config[GOODIX_CFG_LOC_DRVB_NUM] & 0x1f);
if (have_key)
driver_num--;
sensor_num = (ts->config[GOODIX_CFG_LOC_SENS_NUM] & 0x0f) +
((ts->config[GOODIX_CFG_LOC_SENS_NUM] >> 4) & 0x0f);
dev_dbg(&ts->client->dev, "Drv %d Sen %d Key %d\n",
driver_num, sensor_num, have_key);
ts->bak_ref_len = (driver_num * (sensor_num - 2) + 2) * 2;
ts->bak_ref = devm_kzalloc(&ts->client->dev,
ts->bak_ref_len, GFP_KERNEL);
if (!ts->bak_ref)
return -ENOMEM;
/*
* The bak_ref array contains the backup of an array of (self/auto)
* calibration related values which the Android version of the driver
* stores on the filesystem so that it can be restored after reboot.
* The mainline kernel never writes directly to the filesystem like
* this, we always start will all the values which give a correction
* factor in approx. the -20 - +20 range (in 2s complement) set to 0.
*
* Note the touchscreen works fine without restoring the reference
* values after a reboot / power-cycle.
*
* The last 2 bytes are a 16 bits unsigned checksum which is expected
* to make the addition al all 16 bit unsigned values in the array add
* up to 1 (rather then the usual 0), so we must set the last byte to 1.
*/
ts->bak_ref[ts->bak_ref_len - 1] = 1;
return 0;
}
static int goodix_send_main_clock(struct goodix_ts_data *ts)
{
u32 main_clk = 54; /* Default main clock */
u8 checksum = 0;
int i;
device_property_read_u32(&ts->client->dev,
"goodix,main-clk", &main_clk);
for (i = 0; i < (GOODIX_MAIN_CLK_LEN - 1); i++) {
ts->main_clk[i] = main_clk;
checksum += main_clk;
}
/* The value of all bytes combines must be 0 */
ts->main_clk[GOODIX_MAIN_CLK_LEN - 1] = 256 - checksum;
return goodix_i2c_write(ts->client, GOODIX_REG_MAIN_CLK,
ts->main_clk, GOODIX_MAIN_CLK_LEN);
}
int goodix_firmware_check(struct goodix_ts_data *ts)
{
device_property_read_string(&ts->client->dev,
"firmware-name", &ts->firmware_name);
if (!ts->firmware_name)
return 0;
if (ts->irq_pin_access_method == IRQ_PIN_ACCESS_NONE) {
dev_err(&ts->client->dev, "Error no IRQ-pin access method, cannot upload fw.\n");
return -EINVAL;
}
dev_info(&ts->client->dev, "Touchscreen controller needs fw-upload\n");
ts->load_cfg_from_disk = true;
return goodix_firmware_upload(ts);
}
bool goodix_handle_fw_request(struct goodix_ts_data *ts)
{
int error;
u8 val;
error = goodix_i2c_read(ts->client, GOODIX_REG_REQUEST, &val, 1);
if (error)
return false;
switch (val) {
case GOODIX_RQST_RESPONDED:
/*
* If we read back our own last ack the IRQ was not for
* a request.
*/
return false;
case GOODIX_RQST_CONFIG:
error = goodix_send_cfg(ts, ts->config, ts->chip->config_len);
if (error)
return false;
break;
case GOODIX_RQST_BAK_REF:
error = goodix_prepare_bak_ref(ts);
if (error)
return false;
error = goodix_i2c_write(ts->client, GOODIX_REG_BAK_REF,
ts->bak_ref, ts->bak_ref_len);
if (error)
return false;
break;
case GOODIX_RQST_RESET:
error = goodix_firmware_upload(ts);
if (error)
return false;
break;
case GOODIX_RQST_MAIN_CLOCK:
error = goodix_send_main_clock(ts);
if (error)
return false;
break;
case GOODIX_RQST_UNKNOWN:
case GOODIX_RQST_IDLE:
break;
default:
dev_err_ratelimited(&ts->client->dev, "Unknown Request: 0x%02x\n", val);
}
/* Ack the request */
goodix_i2c_write_u8(ts->client,
GOODIX_REG_REQUEST, GOODIX_RQST_RESPONDED);
return true;
}
void goodix_save_bak_ref(struct goodix_ts_data *ts)
{
int error;
u8 val;
if (!ts->firmware_name)
return;
error = goodix_i2c_read(ts->client, GOODIX_REG_STATUS, &val, 1);
if (error)
return;
if (!(val & 0x80))
return;
error = goodix_i2c_read(ts->client, GOODIX_REG_BAK_REF,
ts->bak_ref, ts->bak_ref_len);
if (error) {
memset(ts->bak_ref, 0, ts->bak_ref_len);
ts->bak_ref[ts->bak_ref_len - 1] = 1;
}
}