Input: cyapa - add gen3 trackpad device firmware update support

Add support for firmware image update for gen3 trackpad devices; the
firmware update is initiated by writing to update_fw sysfs attribute.

Signed-off-by: Dudley Du <dudl@cypress.com>
Tested-by: Jeremiah Mahler <jmmahler@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Dudley Du 2015-01-17 22:02:28 -08:00 committed by Dmitry Torokhov
parent c806b0b84d
commit 87b26d7288
1 changed files with 309 additions and 0 deletions

View File

@ -20,6 +20,7 @@
#include <linux/input/mt.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/unaligned/access_ok.h>
#include "cyapa.h"
@ -115,6 +116,18 @@ struct cyapa_reg_data {
struct cyapa_touch touches[5];
} __packed;
struct gen3_write_block_cmd {
u8 checksum_seed; /* Always be 0xff */
u8 cmd_code; /* command code: 0x39 */
u8 key[8]; /* 8-byte security key */
__be16 block_num;
u8 block_data[CYAPA_FW_BLOCK_SIZE];
u8 block_checksum; /* Calculated using bytes 12 - 75 */
u8 cmd_checksum; /* Calculated using bytes 0-76 */
} __packed;
static const u8 security_key[] = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07 };
static const u8 bl_activate[] = { 0x00, 0xff, 0x38, 0x00, 0x01, 0x02, 0x03,
0x04, 0x05, 0x06, 0x07 };
static const u8 bl_deactivate[] = { 0x00, 0xff, 0x3b, 0x00, 0x01, 0x02, 0x03,
@ -423,6 +436,87 @@ static int cyapa_gen3_state_parse(struct cyapa *cyapa, u8 *reg_data, int len)
return -EAGAIN;
}
/*
* Enter bootloader by soft resetting the device.
*
* If device is already in the bootloader, the function just returns.
* Otherwise, reset the device; after reset, device enters bootloader idle
* state immediately.
*
* Returns:
* 0 on success
* -EAGAIN device was reset, but is not now in bootloader idle state
* < 0 if the device never responds within the timeout
*/
static int cyapa_gen3_bl_enter(struct cyapa *cyapa)
{
int error;
int waiting_time;
error = cyapa_poll_state(cyapa, 500);
if (error)
return error;
if (cyapa->state == CYAPA_STATE_BL_IDLE) {
/* Already in BL_IDLE. Skipping reset. */
return 0;
}
if (cyapa->state != CYAPA_STATE_OP)
return -EAGAIN;
cyapa->operational = false;
cyapa->state = CYAPA_STATE_NO_DEVICE;
error = cyapa_write_byte(cyapa, CYAPA_CMD_SOFT_RESET, 0x01);
if (error)
return -EIO;
usleep_range(25000, 50000);
waiting_time = 2000; /* For some shipset, max waiting time is 1~2s. */
do {
error = cyapa_poll_state(cyapa, 500);
if (error) {
if (error == -ETIMEDOUT) {
waiting_time -= 500;
continue;
}
return error;
}
if ((cyapa->state == CYAPA_STATE_BL_IDLE) &&
!(cyapa->status[REG_BL_STATUS] & BL_STATUS_WATCHDOG))
break;
msleep(100);
waiting_time -= 100;
} while (waiting_time > 0);
if ((cyapa->state != CYAPA_STATE_BL_IDLE) ||
(cyapa->status[REG_BL_STATUS] & BL_STATUS_WATCHDOG))
return -EAGAIN;
return 0;
}
static int cyapa_gen3_bl_activate(struct cyapa *cyapa)
{
int error;
error = cyapa_i2c_reg_write_block(cyapa, 0, sizeof(bl_activate),
bl_activate);
if (error)
return error;
/* Wait for bootloader to activate; takes between 2 and 12 seconds */
msleep(2000);
error = cyapa_poll_state(cyapa, 11000);
if (error)
return error;
if (cyapa->state != CYAPA_STATE_BL_ACTIVE)
return -EAGAIN;
return 0;
}
static int cyapa_gen3_bl_deactivate(struct cyapa *cyapa)
{
int error;
@ -483,6 +577,212 @@ static int cyapa_gen3_bl_exit(struct cyapa *cyapa)
return 0;
}
static u16 cyapa_gen3_csum(const u8 *buf, size_t count)
{
int i;
u16 csum = 0;
for (i = 0; i < count; i++)
csum += buf[i];
return csum;
}
/*
* Verify the integrity of a CYAPA firmware image file.
*
* The firmware image file is 30848 bytes, composed of 482 64-byte blocks.
*
* The first 2 blocks are the firmware header.
* The next 480 blocks are the firmware image.
*
* The first two bytes of the header hold the header checksum, computed by
* summing the other 126 bytes of the header.
* The last two bytes of the header hold the firmware image checksum, computed
* by summing the 30720 bytes of the image modulo 0xffff.
*
* Both checksums are stored little-endian.
*/
static int cyapa_gen3_check_fw(struct cyapa *cyapa, const struct firmware *fw)
{
struct device *dev = &cyapa->client->dev;
u16 csum;
u16 csum_expected;
/* Firmware must match exact 30848 bytes = 482 64-byte blocks. */
if (fw->size != CYAPA_FW_SIZE) {
dev_err(dev, "invalid firmware size = %zu, expected %u.\n",
fw->size, CYAPA_FW_SIZE);
return -EINVAL;
}
/* Verify header block */
csum_expected = (fw->data[0] << 8) | fw->data[1];
csum = cyapa_gen3_csum(&fw->data[2], CYAPA_FW_HDR_SIZE - 2);
if (csum != csum_expected) {
dev_err(dev, "%s %04x, expected: %04x\n",
"invalid firmware header checksum = ",
csum, csum_expected);
return -EINVAL;
}
/* Verify firmware image */
csum_expected = (fw->data[CYAPA_FW_HDR_SIZE - 2] << 8) |
fw->data[CYAPA_FW_HDR_SIZE - 1];
csum = cyapa_gen3_csum(&fw->data[CYAPA_FW_HDR_SIZE],
CYAPA_FW_DATA_SIZE);
if (csum != csum_expected) {
dev_err(dev, "%s %04x, expected: %04x\n",
"invalid firmware header checksum = ",
csum, csum_expected);
return -EINVAL;
}
return 0;
}
/*
* Write a |len| byte long buffer |buf| to the device, by chopping it up into a
* sequence of smaller |CYAPA_CMD_LEN|-length write commands.
*
* The data bytes for a write command are prepended with the 1-byte offset
* of the data relative to the start of |buf|.
*/
static int cyapa_gen3_write_buffer(struct cyapa *cyapa,
const u8 *buf, size_t len)
{
int error;
size_t i;
unsigned char cmd[CYAPA_CMD_LEN + 1];
size_t cmd_len;
for (i = 0; i < len; i += CYAPA_CMD_LEN) {
const u8 *payload = &buf[i];
cmd_len = (len - i >= CYAPA_CMD_LEN) ? CYAPA_CMD_LEN : len - i;
cmd[0] = i;
memcpy(&cmd[1], payload, cmd_len);
error = cyapa_i2c_reg_write_block(cyapa, 0, cmd_len + 1, cmd);
if (error)
return error;
}
return 0;
}
/*
* A firmware block write command writes 64 bytes of data to a single flash
* page in the device. The 78-byte block write command has the format:
* <0xff> <CMD> <Key> <Start> <Data> <Data-Checksum> <CMD Checksum>
*
* <0xff> - every command starts with 0xff
* <CMD> - the write command value is 0x39
* <Key> - write commands include an 8-byte key: { 00 01 02 03 04 05 06 07 }
* <Block> - Memory Block number (address / 64) (16-bit, big-endian)
* <Data> - 64 bytes of firmware image data
* <Data Checksum> - sum of 64 <Data> bytes, modulo 0xff
* <CMD Checksum> - sum of 77 bytes, from 0xff to <Data Checksum>
*
* Each write command is split into 5 i2c write transactions of up to 16 bytes.
* Each transaction starts with an i2c register offset: (00, 10, 20, 30, 40).
*/
static int cyapa_gen3_write_fw_block(struct cyapa *cyapa,
u16 block, const u8 *data)
{
int ret;
struct gen3_write_block_cmd write_block_cmd;
u8 status[BL_STATUS_SIZE];
int tries;
u8 bl_status, bl_error;
/* Set write command and security key bytes. */
write_block_cmd.checksum_seed = GEN3_BL_CMD_CHECKSUM_SEED;
write_block_cmd.cmd_code = GEN3_BL_CMD_WRITE_BLOCK;
memcpy(write_block_cmd.key, security_key, sizeof(security_key));
put_unaligned_be16(block, &write_block_cmd.block_num);
memcpy(write_block_cmd.block_data, data, CYAPA_FW_BLOCK_SIZE);
write_block_cmd.block_checksum = cyapa_gen3_csum(
write_block_cmd.block_data, CYAPA_FW_BLOCK_SIZE);
write_block_cmd.cmd_checksum = cyapa_gen3_csum((u8 *)&write_block_cmd,
sizeof(write_block_cmd) - 1);
ret = cyapa_gen3_write_buffer(cyapa, (u8 *)&write_block_cmd,
sizeof(write_block_cmd));
if (ret)
return ret;
/* Wait for write to finish */
tries = 11; /* Programming for one block can take about 100ms. */
do {
usleep_range(10000, 20000);
/* Check block write command result status. */
ret = cyapa_i2c_reg_read_block(cyapa, BL_HEAD_OFFSET,
BL_STATUS_SIZE, status);
if (ret != BL_STATUS_SIZE)
return (ret < 0) ? ret : -EIO;
} while ((status[REG_BL_STATUS] & BL_STATUS_BUSY) && --tries);
/* Ignore WATCHDOG bit and reserved bits. */
bl_status = status[REG_BL_STATUS] & ~BL_STATUS_REV_MASK;
bl_error = status[REG_BL_ERROR] & ~BL_ERROR_RESERVED;
if (bl_status & BL_STATUS_BUSY)
ret = -ETIMEDOUT;
else if (bl_status != BL_STATUS_RUNNING ||
bl_error != BL_ERROR_BOOTLOADING)
ret = -EIO;
else
ret = 0;
return ret;
}
static int cyapa_gen3_write_blocks(struct cyapa *cyapa,
size_t start_block, size_t block_count,
const u8 *image_data)
{
int error;
int i;
for (i = 0; i < block_count; i++) {
size_t block = start_block + i;
size_t addr = i * CYAPA_FW_BLOCK_SIZE;
const u8 *data = &image_data[addr];
error = cyapa_gen3_write_fw_block(cyapa, block, data);
if (error)
return error;
}
return 0;
}
static int cyapa_gen3_do_fw_update(struct cyapa *cyapa,
const struct firmware *fw)
{
struct device *dev = &cyapa->client->dev;
int error;
/* First write data, starting at byte 128 of fw->data */
error = cyapa_gen3_write_blocks(cyapa,
CYAPA_FW_DATA_BLOCK_START, CYAPA_FW_DATA_BLOCK_COUNT,
&fw->data[CYAPA_FW_HDR_BLOCK_COUNT * CYAPA_FW_BLOCK_SIZE]);
if (error) {
dev_err(dev, "FW update aborted, write image: %d\n", error);
return error;
}
/* Then write checksum */
error = cyapa_gen3_write_blocks(cyapa,
CYAPA_FW_HDR_BLOCK_START, CYAPA_FW_HDR_BLOCK_COUNT,
&fw->data[0]);
if (error) {
dev_err(dev, "FW update aborted, write checksum: %d\n", error);
return error;
}
return 0;
}
/*
* cyapa_get_wait_time_for_pwr_cmd
*
@ -791,10 +1091,19 @@ static int cyapa_gen3_irq_handler(struct cyapa *cyapa)
}
static int cyapa_gen3_initialize(struct cyapa *cyapa) { return 0; }
static int cyapa_gen3_bl_initiate(struct cyapa *cyapa,
const struct firmware *fw) { return 0; }
static int cyapa_gen3_empty_output_data(struct cyapa *cyapa,
u8 *buf, int *len, cb_sort func) { return 0; }
const struct cyapa_dev_ops cyapa_gen3_ops = {
.check_fw = cyapa_gen3_check_fw,
.bl_enter = cyapa_gen3_bl_enter,
.bl_activate = cyapa_gen3_bl_activate,
.update_fw = cyapa_gen3_do_fw_update,
.bl_deactivate = cyapa_gen3_bl_deactivate,
.bl_initiate = cyapa_gen3_bl_initiate,
.initialize = cyapa_gen3_initialize,
.state_parse = cyapa_gen3_state_parse,