On Jul 13 2016 or thereabouts, Andrew Duggan wrote:
> Commit 5b65c2a02966 ("HID: rmi: check sanity of the incoming report") added
> support for handling incomplete HID reports do to the input data being
> corrupted in transit. This patch reimplements this functionality in the
> function drivers so they can handle getting less valid data then they
> expect.
>
> Signed-off-by: Andrew Duggan <adug...@synaptics.com>
Acked-by: Benjamin Tissoires <benjamin.tissoi...@redhat.com>
> ---
> In the v2 version I moved the RMI_F11_REL_BYTES hunk to patch 8 and fixed
> the spelling of f_state. This is the same as the v2 version.
>
> drivers/input/rmi4/rmi_f11.c | 54
> ++++++++++++++++++++++++++++++++------------
> drivers/input/rmi4/rmi_f12.c | 23 ++++++++++++++-----
> drivers/input/rmi4/rmi_f30.c | 4 ++++
> 3 files changed, 61 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/input/rmi4/rmi_f11.c b/drivers/input/rmi4/rmi_f11.c
> index 688e604..3fda75b 100644
> --- a/drivers/input/rmi4/rmi_f11.c
> +++ b/drivers/input/rmi4/rmi_f11.c
> @@ -572,31 +572,48 @@ static inline u8 rmi_f11_parse_finger_state(const u8
> *f_state, u8 n_finger)
>
> static void rmi_f11_finger_handler(struct f11_data *f11,
> struct rmi_2d_sensor *sensor,
> - unsigned long *irq_bits, int num_irq_regs)
> + unsigned long *irq_bits, int num_irq_regs,
> + int size)
> {
> const u8 *f_state = f11->data.f_state;
> u8 finger_state;
> u8 i;
> + int abs_fingers;
> + int rel_fingers;
> + int abs_size = sensor->nbr_fingers * RMI_F11_ABS_BYTES;
>
> int abs_bits = bitmap_and(f11->result_bits, irq_bits, f11->abs_mask,
> num_irq_regs * 8);
> int rel_bits = bitmap_and(f11->result_bits, irq_bits, f11->rel_mask,
> num_irq_regs * 8);
>
> - for (i = 0; i < sensor->nbr_fingers; i++) {
> - /* Possible of having 4 fingers per f_statet register */
> - finger_state = rmi_f11_parse_finger_state(f_state, i);
> - if (finger_state == F11_RESERVED) {
> - pr_err("Invalid finger state[%d]: 0x%02x", i,
> - finger_state);
> - continue;
> - }
> + if (abs_bits) {
> + if (abs_size > size)
> + abs_fingers = size / RMI_F11_ABS_BYTES;
> + else
> + abs_fingers = sensor->nbr_fingers;
> +
> + for (i = 0; i < abs_fingers; i++) {
> + /* Possible of having 4 fingers per f_state register */
> + finger_state = rmi_f11_parse_finger_state(f_state, i);
> + if (finger_state == F11_RESERVED) {
> + pr_err("Invalid finger state[%d]: 0x%02x", i,
> + finger_state);
> + continue;
> + }
>
> - if (abs_bits)
> rmi_f11_abs_pos_process(f11, sensor, &sensor->objs[i],
> finger_state, i);
> + }
> + }
> +
> + if (rel_bits) {
> + if ((abs_size + sensor->nbr_fingers * RMI_F11_REL_BYTES) > size)
> + rel_fingers = (size - abs_size) / RMI_F11_REL_BYTES;
> + else
> + rel_fingers = sensor->nbr_fingers;
>
> - if (rel_bits)
> + for (i = 0; i < rel_fingers; i++)
> rmi_f11_rel_pos_report(f11, i);
> }
>
> @@ -612,7 +629,7 @@ static void rmi_f11_finger_handler(struct f11_data *f11,
> sensor->nbr_fingers,
> sensor->dmax);
>
> - for (i = 0; i < sensor->nbr_fingers; i++) {
> + for (i = 0; i < abs_fingers; i++) {
> finger_state = rmi_f11_parse_finger_state(f_state, i);
> if (finger_state == F11_RESERVED)
> /* no need to send twice the error */
> @@ -1266,10 +1283,19 @@ static int rmi_f11_attention(struct rmi_function *fn,
> unsigned long *irq_bits)
> struct f11_data *f11 = dev_get_drvdata(&fn->dev);
> u16 data_base_addr = fn->fd.data_base_addr;
> int error;
> + int valid_bytes = f11->sensor.pkt_size;
>
> if (rmi_dev->xport->attn_data) {
> + /*
> + * The valid data in the attention report is less then
> + * expected. Only process the complete fingers.
> + */
> + if (f11->sensor.attn_size > rmi_dev->xport->attn_size)
> + valid_bytes = rmi_dev->xport->attn_size;
> + else
> + valid_bytes = f11->sensor.attn_size;
> memcpy(f11->sensor.data_pkt, rmi_dev->xport->attn_data,
> - f11->sensor.attn_size);
> + valid_bytes);
> rmi_dev->xport->attn_data += f11->sensor.attn_size;
> rmi_dev->xport->attn_size -= f11->sensor.attn_size;
> } else {
> @@ -1281,7 +1307,7 @@ static int rmi_f11_attention(struct rmi_function *fn,
> unsigned long *irq_bits)
> }
>
> rmi_f11_finger_handler(f11, &f11->sensor, irq_bits,
> - drvdata->num_of_irq_regs);
> + drvdata->num_of_irq_regs, valid_bytes);
>
> return 0;
> }
> diff --git a/drivers/input/rmi4/rmi_f12.c b/drivers/input/rmi4/rmi_f12.c
> index 7d66766..c30fd86 100644
> --- a/drivers/input/rmi4/rmi_f12.c
> +++ b/drivers/input/rmi4/rmi_f12.c
> @@ -26,6 +26,8 @@ enum rmi_f12_object_type {
> RMI_F12_OBJECT_SMALL_OBJECT = 0x0D,
> };
>
> +#define F12_DATA1_BYTES_PER_OBJ 8
> +
> struct f12_data {
> struct rmi_2d_sensor sensor;
> struct rmi_2d_sensor_platform_data sensor_pdata;
> @@ -146,12 +148,16 @@ static int rmi_f12_read_sensor_tuning(struct f12_data
> *f12)
> return 0;
> }
>
> -static void rmi_f12_process_objects(struct f12_data *f12, u8 *data1)
> +static void rmi_f12_process_objects(struct f12_data *f12, u8 *data1, int
> size)
> {
> int i;
> struct rmi_2d_sensor *sensor = &f12->sensor;
> + int objects = f12->data1->num_subpackets;
> +
> + if ((f12->data1->num_subpackets * F12_DATA1_BYTES_PER_OBJ) > size)
> + objects = size / F12_DATA1_BYTES_PER_OBJ;
>
> - for (i = 0; i < f12->data1->num_subpackets; i++) {
> + for (i = 0; i < objects; i++) {
> struct rmi_2d_sensor_abs_object *obj = &sensor->objs[i];
>
> obj->type = RMI_2D_OBJECT_NONE;
> @@ -182,7 +188,7 @@ static void rmi_f12_process_objects(struct f12_data *f12,
> u8 *data1)
>
> rmi_2d_sensor_abs_process(sensor, obj, i);
>
> - data1 += 8;
> + data1 += F12_DATA1_BYTES_PER_OBJ;
> }
>
> if (sensor->kernel_tracking)
> @@ -192,7 +198,7 @@ static void rmi_f12_process_objects(struct f12_data *f12,
> u8 *data1)
> sensor->nbr_fingers,
> sensor->dmax);
>
> - for (i = 0; i < sensor->nbr_fingers; i++)
> + for (i = 0; i < objects; i++)
> rmi_2d_sensor_abs_report(sensor, &sensor->objs[i], i);
> }
>
> @@ -203,10 +209,15 @@ static int rmi_f12_attention(struct rmi_function *fn,
> struct rmi_device *rmi_dev = fn->rmi_dev;
> struct f12_data *f12 = dev_get_drvdata(&fn->dev);
> struct rmi_2d_sensor *sensor = &f12->sensor;
> + int valid_bytes = sensor->pkt_size;
>
> if (rmi_dev->xport->attn_data) {
> + if (sensor->attn_size > rmi_dev->xport->attn_size)
> + valid_bytes = rmi_dev->xport->attn_size;
> + else
> + valid_bytes = sensor->attn_size;
> memcpy(sensor->data_pkt, rmi_dev->xport->attn_data,
> - sensor->attn_size);
> + valid_bytes);
> rmi_dev->xport->attn_data += sensor->attn_size;
> rmi_dev->xport->attn_size -= sensor->attn_size;
> } else {
> @@ -221,7 +232,7 @@ static int rmi_f12_attention(struct rmi_function *fn,
>
> if (f12->data1)
> rmi_f12_process_objects(f12,
> - &sensor->data_pkt[f12->data1_offset]);
> + &sensor->data_pkt[f12->data1_offset], valid_bytes);
>
> input_mt_sync_frame(sensor->input);
>
> diff --git a/drivers/input/rmi4/rmi_f30.c b/drivers/input/rmi4/rmi_f30.c
> index 760aff1..485907f 100644
> --- a/drivers/input/rmi4/rmi_f30.c
> +++ b/drivers/input/rmi4/rmi_f30.c
> @@ -110,6 +110,10 @@ static int rmi_f30_attention(struct rmi_function *fn,
> unsigned long *irq_bits)
>
> /* Read the gpi led data. */
> if (rmi_dev->xport->attn_data) {
> + if (rmi_dev->xport->attn_size < f30->register_count) {
> + dev_warn(&fn->dev, "F30 interrupted, but data is
> missing\n");
> + return 0;
> + }
> memcpy(f30->data_regs, rmi_dev->xport->attn_data,
> f30->register_count);
> rmi_dev->xport->attn_data += f30->register_count;
> --
> 2.5.0
>
