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-rw-r--r--drivers/input/keyboard/stmpe-keypad.c37
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)