Dudley,
On Mon, Dec 15, 2014 at 02:23:17PM +0800, Dudley Du wrote:
> 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 <dudley.dulixin@xxxxxxxxx>
> ---
> drivers/input/mouse/cyapa_gen3.c | 284 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 284 insertions(+)
>
> diff --git a/drivers/input/mouse/cyapa_gen3.c b/drivers/input/mouse/cyapa_gen3.c
> index 433c5b1..9851337 100644
> --- a/drivers/input/mouse/cyapa_gen3.c
> +++ b/drivers/input/mouse/cyapa_gen3.c
> @@ -416,6 +416,72 @@ 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.
> + *
> + * Also, if device was unregister device from input core. Device will
> + * re-register after it is detected following resumption of operational mode.
> + *
I don't quite understand this. Tell me if the following re-wording is
correct.
+ * Also, if the device was unregistered from the input core, the device
+ * will re-register after it is detected following resumption of
+ * operational mode.
> + * 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
Could be formatted nicer. Tell me if the re-wording makes sense.
+ * 0 on success
+ * -EAGAIN if device was reset, but it is not 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;
> @@ -476,6 +542,218 @@ static int cyapa_gen3_bl_exit(struct cyapa *cyapa)
> return 0;
> }
>
> +/* Used in gen3 bootloader commands. */
We should be able to figure out where it is used. Unnecessary comment?
> +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;
> + u8 cmd[78];
> + u8 status[BL_STATUS_SIZE];
> + /* Programming for one block can take about 100ms. */
> + int tries = 11;
> + u8 bl_status, bl_error;
> +
> + /* Set write command and security key bytes. */
> + cmd[0] = 0xff;
> + cmd[1] = 0x39;
> + cmd[2] = 0x00;
> + cmd[3] = 0x01;
> + cmd[4] = 0x02;
> + cmd[5] = 0x03;
> + cmd[6] = 0x04;
> + cmd[7] = 0x05;
> + cmd[8] = 0x06;
> + cmd[9] = 0x07;
> + cmd[10] = block >> 8;
> + cmd[11] = block;
> + memcpy(&cmd[12], data, CYAPA_FW_BLOCK_SIZE);
> + cmd[76] = cyapa_gen3_csum(data, CYAPA_FW_BLOCK_SIZE);
> + cmd[77] = cyapa_gen3_csum(cmd, sizeof(cmd) - 1);
> +
Sequences like these are used all over this code. I wish there was a
cleaner and more descriptive way to describe what is being constructed.
Perhaps using a struct?
> + ret = cyapa_gen3_write_buffer(cyapa, cmd, sizeof(cmd));
> + if (ret)
> + return ret;
> +
> + /* Wait for write to finish */
> + 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 */
^
extra space
> + 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
> *
> @@ -783,6 +1061,12 @@ static int cyapa_gen3_irq_handler(struct cyapa *cyapa)
> }
>
> 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,
> +
> .state_parse = cyapa_gen3_state_parse,
> .operational_check = cyapa_gen3_do_operational_check,
>
> --
> 1.9.1
>
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--
- Jeremiah Mahler
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