diff options
Diffstat (limited to 'drivers/input/keyboard')
| -rw-r--r-- | drivers/input/keyboard/stmpe-keypad.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/drivers/input/keyboard/stmpe-keypad.c b/drivers/input/keyboard/stmpe-keypad.c index 8d1e7af3c5b1..64514e64d557 100644 --- a/drivers/input/keyboard/stmpe-keypad.c +++ b/drivers/input/keyboard/stmpe-keypad.c @@ -52,6 +52,7 @@ * struct stmpe_keypad_variant - model-specific attributes * @auto_increment: whether the KPC_DATA_BYTE register address * auto-increments on multiple read + * @set_pullup: whether the pins need to have their pull-ups set * @num_data: number of data bytes * @num_normal_data: number of normal keys' data bytes * @max_cols: maximum number of columns supported @@ -61,6 +62,7 @@ */ struct stmpe_keypad_variant { bool auto_increment; + bool set_pullup; int num_data; int num_normal_data; int max_cols; @@ -81,6 +83,7 @@ static const struct stmpe_keypad_variant stmpe_keypad_variants[] = { }, [STMPE2401] = { .auto_increment = false, + .set_pullup = true, .num_data = 3, .num_normal_data = 2, .max_cols = 8, @@ -90,6 +93,7 @@ static const struct stmpe_keypad_variant stmpe_keypad_variants[] = { }, [STMPE2403] = { .auto_increment = true, + .set_pullup = true, .num_data = 5, .num_normal_data = 3, .max_cols = 8, @@ -185,7 +189,10 @@ static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad) unsigned int col_gpios = variant->col_gpios; unsigned int row_gpios = variant->row_gpios; struct stmpe *stmpe = keypad->stmpe; + u8 pureg = stmpe->regs[STMPE_IDX_GPPUR_LSB]; unsigned int pins = 0; + unsigned int pu_pins = 0; + int ret; int i; /* @@ -202,8 +209,10 @@ static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad) for (i = 0; i < variant->max_cols; i++) { int num = __ffs(col_gpios); - if (keypad->cols & (1 << i)) + if (keypad->cols & (1 << i)) { pins |= 1 << num; + pu_pins |= 1 << num; + } col_gpios &= ~(1 << num); } @@ -217,7 +226,31 @@ static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad) row_gpios &= ~(1 << num); } - return stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD); + ret = stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD); + if (ret) + return ret; + + /* + * On STMPE24xx, set pin bias to pull-up on all keypad input + * pins (columns), this incidentally happen to be maximum 8 pins + * and placed at GPIO0-7 so only the LSB of the pull up register + * ever needs to be written. + */ + if (variant->set_pullup) { + u8 val; + + ret = stmpe_reg_read(stmpe, pureg); + if (ret) + return ret; + + /* Do not touch unused pins, may be used for GPIO */ + val = ret & ~pu_pins; + val |= pu_pins; + + ret = stmpe_reg_write(stmpe, pureg, val); + } + + return 0; } static int stmpe_keypad_chip_init(struct stmpe_keypad *keypad) |