Hi Neil,
On Sat, Oct 21, 2023 at 01:09:24PM +0200, Neil Armstrong wrote:
> +static int goodix_berlin_get_ic_info(struct goodix_berlin_core *cd)
> +{
> + u8 afe_data[GOODIX_BERLIN_IC_INFO_MAX_LEN];
You probably already saw the kernel test robot message, I think we
should allocate this buffer in the heap (and free it once its no longer
needed).
> + __le16 length_raw;
> + u16 length;
> + int error;
> +
> + error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_IC_INFO_ADDR,
> + &length_raw, sizeof(length_raw));
> + if (error) {
> + dev_info(cd->dev, "failed get ic info length, %d\n", error);
> + return error;
> + }
> +
> + length = le16_to_cpu(length_raw);
> + if (length >= GOODIX_BERLIN_IC_INFO_MAX_LEN) {
> + dev_info(cd->dev, "invalid ic info length %d\n", length);
> + return -EINVAL;
> + }
> +
> + error = regmap_raw_read(cd->regmap, GOODIX_BERLIN_IC_INFO_ADDR,
> + afe_data, length);
> + if (error) {
> + dev_info(cd->dev, "failed get ic info data, %d\n", error);
> + return error;
> + }
> +
> + /* check whether the data is valid (ex. bus default values) */
> + if (goodix_berlin_is_dummy_data(cd, (const uint8_t *)afe_data, length)) {
This cast is not needed.
> + dev_err(cd->dev, "fw info data invalid\n");
> + return -EINVAL;
> + }
> +
> + if (!goodix_berlin_checksum_valid((const uint8_t *)afe_data, length)) {
This cast is not needed either.
> + dev_info(cd->dev, "fw info checksum error\n");
> + return -EINVAL;
> + }
> +
> + error = goodix_berlin_convert_ic_info(cd, afe_data, length);
> + if (error)
> + return error;
> +
> + /* check some key info */
> + if (!cd->touch_data_addr) {
> + dev_err(cd->dev, "touch_data_addr is null\n");
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static void goodix_berlin_parse_finger(struct goodix_berlin_core *cd,
> + const void *buf, int touch_num)
> +{
> + const struct goodix_berlin_touch_data *touch_data = buf;
> + int i;
> +
> + /* Check for data validity */
> + for (i = 0; i < touch_num; i++) {
> + unsigned int id;
> +
> + id = FIELD_GET(GOODIX_BERLIN_TOUCH_ID_MASK, touch_data[i].id);
> +
> + if (id >= GOODIX_BERLIN_MAX_TOUCH) {
> + dev_warn(cd->dev, "invalid finger id %d\n", id);
> + return;
Is it important to abort entire packet if one if the slots has incorrect
data? Can we simply skip over these contacts?
> + }
> + }
> +
> + /* Report finger touches */
> + for (i = 0; i < touch_num; i++) {
> + input_mt_slot(cd->input_dev,
> + FIELD_GET(GOODIX_BERLIN_TOUCH_ID_MASK,
> + touch_data[i].id));
> + input_mt_report_slot_state(cd->input_dev, MT_TOOL_FINGER, true);
> +
> + touchscreen_report_pos(cd->input_dev, &cd->props,
> + __le16_to_cpu(touch_data[i].x),
> + __le16_to_cpu(touch_data[i].y),
> + true);
> + input_report_abs(cd->input_dev, ABS_MT_TOUCH_MAJOR,
> + __le16_to_cpu(touch_data[i].w));
> + }
> +
> + input_mt_sync_frame(cd->input_dev);
> + input_sync(cd->input_dev);
> +}
> +
> +static void goodix_berlin_touch_handler(struct goodix_berlin_core *cd,
> + const void *pre_buf, u32 pre_buf_len)
> +{
> + static u8 buffer[GOODIX_BERLIN_IRQ_READ_LEN(GOODIX_BERLIN_MAX_TOUCH)];
No, please no static data. The drivers should be ready to handle more
than one device on a system. If the buffer is large-ish put it into
goodix_berlin_core.
> + u8 point_type, touch_num;
> + int error;
> +
> + /* copy pre-data to buffer */
> + memcpy(buffer, pre_buf, pre_buf_len);
> +
> + touch_num = FIELD_GET(GOODIX_BERLIN_TOUCH_COUNT_MASK,
> + buffer[GOODIX_BERLIN_REQUEST_TYPE_OFFSET]);
> +
> + if (touch_num > GOODIX_BERLIN_MAX_TOUCH) {
> + dev_warn(cd->dev, "invalid touch num %d\n", touch_num);
> + return;
> + }
> +
> + if (touch_num) {
> + /* read more data if more than 2 touch events */
> + if (unlikely(touch_num > 2)) {
> + error = regmap_raw_read(cd->regmap,
> + cd->touch_data_addr + pre_buf_len,
> + &buffer[pre_buf_len],
> + (touch_num - 2) * GOODIX_BERLIN_BYTES_PER_POINT);
> + if (error) {
> + dev_err_ratelimited(cd->dev, "failed to get touch data, %d\n",
> + error);
> + return;
> + }
> + }
> +
> + point_type = FIELD_GET(GOODIX_BERLIN_POINT_TYPE_MASK,
> + buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN]);
> +
> + if (point_type == GOODIX_BERLIN_POINT_TYPE_STYLUS ||
> + point_type == GOODIX_BERLIN_POINT_TYPE_STYLUS_HOVER) {
> + dev_warn_once(cd->dev, "Stylus event type not handled\n");
> + return;
> + }
> +
> + if (!goodix_berlin_checksum_valid(&buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN],
> + touch_num * GOODIX_BERLIN_BYTES_PER_POINT + 2)) {
> + dev_err(cd->dev, "touch data checksum error, data: %*ph\n",
> + touch_num * GOODIX_BERLIN_BYTES_PER_POINT + 2,
> + &buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN]);
> + return;
> + }
> + }
> +
> + goodix_berlin_parse_finger(cd, &buffer[GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN],
> + touch_num);
> +}
> +
> +static int goodix_berlin_request_handle_reset(struct goodix_berlin_core *cd)
> +{
> + gpiod_set_value(cd->reset_gpio, 1);
> + usleep_range(2000, 2100);
> + gpiod_set_value(cd->reset_gpio, 0);
> +
> + msleep(GOODIX_BERLIN_NORMAL_RESET_DELAY_MS);
The reset line handling is optional, we should skip waits if there is
no GPIO defined for the board.
> +
> + return 0;
> +}
> +
> +static irqreturn_t goodix_berlin_threadirq_func(int irq, void *data)
> +{
> + struct goodix_berlin_core *cd = data;
> + u8 buf[GOODIX_BERLIN_IRQ_READ_LEN(2)];
> + u8 event_status;
> + int error;
> +
> + /* First, read buffer with space for 2 touch events */
> + error = regmap_raw_read(cd->regmap, cd->touch_data_addr, buf,
> + GOODIX_BERLIN_IRQ_READ_LEN(2));
> + if (error) {
> + dev_err_ratelimited(cd->dev, "failed get event head data, %d\n", error);
> + return IRQ_HANDLED;
> + }
> +
> + if (buf[GOODIX_BERLIN_STATUS_OFFSET] == 0)
> + return IRQ_HANDLED;
> +
> + if (!goodix_berlin_checksum_valid(buf, GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN)) {
> + dev_warn_ratelimited(cd->dev, "touch head checksum err : %*ph\n",
> + GOODIX_BERLIN_IRQ_EVENT_HEAD_LEN, buf);
> + return IRQ_HANDLED;
> + }
> +
> + event_status = buf[GOODIX_BERLIN_STATUS_OFFSET];
> +
> + if (event_status & GOODIX_BERLIN_TOUCH_EVENT)
> + goodix_berlin_touch_handler(cd, buf, GOODIX_BERLIN_IRQ_READ_LEN(2));
> +
> + if (event_status & GOODIX_BERLIN_REQUEST_EVENT) {
> + switch (buf[GOODIX_BERLIN_REQUEST_TYPE_OFFSET]) {
> + case GOODIX_BERLIN_REQUEST_CODE_RESET:
> + goodix_berlin_request_handle_reset(cd);
> + break;
> +
> + default:
> + dev_warn(cd->dev, "unsupported request code 0x%x\n",
> + buf[GOODIX_BERLIN_REQUEST_TYPE_OFFSET]);
> + }
> + }
> +
> + /* Clear up status field */
> + regmap_write(cd->regmap, cd->touch_data_addr, 0);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int goodix_berlin_input_dev_config(struct goodix_berlin_core *cd,
> + const struct input_id *id)
> +{
> + struct input_dev *input_dev;
> + int error;
> +
> + input_dev = devm_input_allocate_device(cd->dev);
> + if (!input_dev)
> + return -ENOMEM;
> +
> + cd->input_dev = input_dev;
> + input_set_drvdata(input_dev, cd);
> +
> + input_dev->name = "Goodix Berlin Capacitive TouchScreen";
> + input_dev->phys = "input/ts";
> +
> + input_dev->id = *id;
> +
> + input_set_abs_params(cd->input_dev, ABS_MT_POSITION_X, 0, SZ_64K - 1, 0, 0);
> + input_set_abs_params(cd->input_dev, ABS_MT_POSITION_Y, 0, SZ_64K - 1, 0, 0);
> + input_set_abs_params(cd->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
> +
> + touchscreen_parse_properties(cd->input_dev, true, &cd->props);
> +
> + error = input_mt_init_slots(cd->input_dev, GOODIX_BERLIN_MAX_TOUCH,
> + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
> + if (error)
> + return error;
> +
> + return input_register_device(cd->input_dev);
Please in functions with multiple possible failure paths use format
error = op(...);
if (error)
return error;
return 0;
Thanks.
--
Dmitry
