[PATCH v3 1/8] Input: atmel_mxt_ts - add support for T37 diagnostic data

Nick Dyer
2016-06-01T16:40:10Z

Atmel maXTouch devices have a T37 object which can be used to read raw
touch deltas from the device. This consists of an array of 16-bit
integers, one for each node on the touchscreen matrix.

Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 152 +++++++++++++++++++++++++++++++
1 file changed, 152 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 5af7907..21f42ed 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -124,6 +124,17 @@ struct t9_range {
#define MXT_COMMS_CTRL 0
#define MXT_COMMS_CMD 1

+/* MXT_DEBUG_DIAGNOSTIC_T37 */
+#define MXT_DIAGNOSTIC_PAGEUP 0x01
+#define MXT_DIAGNOSTIC_DELTAS 0x10
+#define MXT_DIAGNOSTIC_SIZE 128
+
+struct t37_debug {
+ u8 mode;
+ u8 page;
+ u8 data[MXT_DIAGNOSTIC_SIZE];
+};
+
/* Define for MXT_GEN_COMMAND_T6 */
#define MXT_BOOT_VALUE 0xa5
#define MXT_RESET_VALUE 0x01
@@ -205,6 +216,14 @@ struct mxt_object {
u8 num_report_ids;
} __packed;

+struct mxt_dbg {
+ u16 t37_address;
+ u16 diag_cmd_address;
+ struct t37_debug *t37_buf;
+ unsigned int t37_pages;
+ unsigned int t37_nodes;
+};
+
/* Each client has this additional data */
struct mxt_data {
struct i2c_client *client;
@@ -233,6 +252,7 @@ struct mxt_data {
u8 num_touchids;
u8 multitouch;
struct t7_config t7_cfg;
+ struct mxt_dbg dbg;

/* Cached parameters from object table */
u16 T5_address;
@@ -2043,6 +2063,136 @@ recheck:
return 0;
}

+static u16 mxt_get_debug_value(struct mxt_data *data, unsigned int x,
+ unsigned int y)
+{
+ struct mxt_dbg *dbg = &data->dbg;
+ unsigned int ofs, page;
+
+ ofs = (y + (x * data->info.matrix_ysize)) * sizeof(u16);
+ page = ofs / MXT_DIAGNOSTIC_SIZE;
+ ofs %= MXT_DIAGNOSTIC_SIZE;
+
+ return get_unaligned_le16(&dbg->t37_buf[page].data[ofs]);
+}
+
+static int mxt_convert_debug_pages(struct mxt_data *data, u16 *outbuf)
+{
+ struct mxt_dbg *dbg = &data->dbg;
+ unsigned int x = 0;
+ unsigned int y = 0;
+ unsigned int i;
+
+ for (i = 0; i < dbg->t37_nodes; i++) {
+ outbuf[i] = mxt_get_debug_value(data, x, y);
+
+ /* Next value */
+ if (++x >= data->info.matrix_xsize) {
+ x = 0;
+ y++;
+ }
+ }
+
+ return 0;
+}
+
+static int mxt_read_diagnostic_debug(struct mxt_data *data, u8 mode,
+ u16 *outbuf)
+{
+ struct mxt_dbg *dbg = &data->dbg;
+ int retries = 0;
+ int page;
+ int ret;
+ u8 cmd = mode;
+ struct t37_debug *p;
+ u8 cmd_poll;
+
+ for (page = 0; page < dbg->t37_pages; page++) {
+ p = dbg->t37_buf + page;
+
+ ret = mxt_write_reg(data->client, dbg->diag_cmd_address,
+ cmd);
+ if (ret)
+ return ret;
+
+ retries = 0;
+ msleep(20);
+wait_cmd:
+ /* Read back command byte */
+ ret = __mxt_read_reg(data->client, dbg->diag_cmd_address,
+ sizeof(cmd_poll), &cmd_poll);
+ if (ret)
+ return ret;
+
+ /* Field is cleared once the command has been processed */
+ if (cmd_poll) {
+ if (retries++ > 100)
+ return -EINVAL;
+
+ msleep(20);
+ goto wait_cmd;
+ }
+
+ /* Read T37 page */
+ ret = __mxt_read_reg(data->client, dbg->t37_address,
+ sizeof(struct t37_debug), p);
+ if (ret)
+ return ret;
+
+ if ((p->mode != mode) || (p->page != page)) {
+ dev_err(&data->client->dev, "T37 page mismatch\n");
+ return -EINVAL;
+ }
+
+ dev_dbg(&data->client->dev, "%s page:%d retries:%d\n",
+ __func__, page, retries);
+
+ /* For remaining pages, write PAGEUP rather than mode */
+ cmd = MXT_DIAGNOSTIC_PAGEUP;
+ }
+
+ return mxt_convert_debug_pages(data, outbuf);
+}
+
+static void mxt_debug_init(struct mxt_data *data)
+{
+ struct mxt_dbg *dbg = &data->dbg;
+ struct mxt_object *object;
+
+ object = mxt_get_object(data, MXT_GEN_COMMAND_T6);
+ if (!object)
+ return;
+
+ dbg->diag_cmd_address = object->start_address + MXT_COMMAND_DIAGNOSTIC;
+
+ object = mxt_get_object(data, MXT_DEBUG_DIAGNOSTIC_T37);
+ if (!object)
+ return;
+
+ if (mxt_obj_size(object) != sizeof(struct t37_debug)) {
+ dev_warn(&data->client->dev, "Bad T37 size");
+ return;
+ }
+
+ dbg->t37_address = object->start_address;
+
+ /* Calculate size of data and allocate buffer */
+ dbg->t37_nodes = data->info.matrix_xsize * data->info.matrix_ysize;
+ dbg->t37_pages = dbg->t37_nodes * sizeof(u16)
+ / sizeof(dbg->t37_buf->data) + 1;
+
+ dbg->t37_buf = devm_kzalloc(&data->client->dev,
+ sizeof(struct t37_debug) * dbg->t37_pages,
+ GFP_KERNEL);
+ if (!dbg->t37_buf)
+ goto error;
+
+ return;
+
+error:
+ dev_err(&data->client->dev, "Error initialising T37 diagnostic data\n");
+}
+
static int mxt_configure_objects(struct mxt_data *data,
const struct firmware *cfg)
{
@@ -2070,6 +2220,8 @@ static int mxt_configure_objects(struct mxt_data *data,
dev_warn(dev, "No touch object detected\n");
}

+ mxt_debug_init(data);
+
dev_info(dev,
"Family: %u Variant: %u Firmware V%u.%u.%02X Objects: %u\n",
info->family_id, info->variant_id, info->version >> 4,
--
2.5.0