Add firmware image update function supported for gen3 trackpad device, it can be used through sysfs update_fw interface. TEST=test on Chromebooks. Signed-off-by: Dudley Du <dudl@xxxxxxxxxxx> --- drivers/input/mouse/cyapa_gen3.c | 291 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 291 insertions(+) diff --git a/drivers/input/mouse/cyapa_gen3.c b/drivers/input/mouse/cyapa_gen3.c index 1b62c7d..715abda 100644 --- a/drivers/input/mouse/cyapa_gen3.c +++ b/drivers/input/mouse/cyapa_gen3.c @@ -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 +436,69 @@ 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; + + 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->state = CYAPA_STATE_NO_DEVICE; + error = cyapa_write_byte(cyapa, CYAPA_CMD_SOFT_RESET, 0x01); + if (error) + return -EIO; + + usleep_range(25000, 50000); + error = cyapa_poll_state(cyapa, 500); + if (error) + return error; + 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 +559,212 @@ 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 +1073,19 @@ 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, -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html