diff options
| author | Luca Ellero <l.ellero@asem.it> | 2023-01-26 11:52:26 +0100 |
|---|---|---|
| committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2023-01-29 18:33:45 -0800 |
| commit | 13f82ca3878db8284a70ef9711d7f710a31eb562 (patch) | |
| tree | 8b608d871cc9704bd8f9bdeaf0a2ee073454450c /drivers/input | |
| parent | d50584d783313c8b05b84d0b07a2142f1bde46dd (diff) | |
Input: ads7846 - always set last command to PWRDOWN
Controllers that report pressure (e.g. ADS7846) use 5 commands and the
correct sequence is READ_X, READ_Y, READ_Z1, READ_Z2, PWRDOWN.
Controllers that don't report pressure (e.g. ADS7845/ADS7843) use only 3
commands and the correct sequence should be READ_X, READ_Y, PWRDOWN. But
the sequence sent was incorrect: READ_X, READ_Y, READ_Z1.
Fix this by setting the third (and last) command to PWRDOWN.
Fixes: ffa458c1bd9b ("spi: ads7846 driver")
Signed-off-by: Luca Ellero <l.ellero@asem.it>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230126105227.47648-3-l.ellero@asem.it
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input')
| -rw-r--r-- | drivers/input/touchscreen/ads7846.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c index f11b444f2138..15da1047a577 100644 --- a/drivers/input/touchscreen/ads7846.c +++ b/drivers/input/touchscreen/ads7846.c @@ -1066,6 +1066,9 @@ static int ads7846_setup_spi_msg(struct ads7846 *ts, struct ads7846_buf_layout *l = &packet->l[cmd_idx]; unsigned int max_count; + if (cmd_idx == packet->cmds - 1) + cmd_idx = ADS7846_PWDOWN; + if (ads7846_cmd_need_settle(cmd_idx)) max_count = packet->count + packet->count_skip; else @@ -1102,7 +1105,12 @@ static int ads7846_setup_spi_msg(struct ads7846 *ts, for (cmd_idx = 0; cmd_idx < packet->cmds; cmd_idx++) { struct ads7846_buf_layout *l = &packet->l[cmd_idx]; - u8 cmd = ads7846_get_cmd(cmd_idx, vref); + u8 cmd; + + if (cmd_idx == packet->cmds - 1) + cmd_idx = ADS7846_PWDOWN; + + cmd = ads7846_get_cmd(cmd_idx, vref); for (b = 0; b < l->count; b++) packet->tx[l->offset + b].cmd = cmd; |