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-rw-r--r--drivers/gpio/max730x.c22
-rw-r--r--include/linux/spi/max7301.h8
2 files changed, 23 insertions, 7 deletions
diff --git a/drivers/gpio/max730x.c b/drivers/gpio/max730x.c
index 7696a56..94ce773 100644
--- a/drivers/gpio/max730x.c
+++ b/drivers/gpio/max730x.c
@@ -54,7 +54,7 @@ static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct max7301 *ts = container_of(chip, struct max7301, chip);
u8 *config;
- u8 offset_bits;
+ u8 offset_bits, pin_config;
int ret;
/* First 4 pins are unused in the controller */
@@ -63,12 +63,15 @@ static int max7301_direction_input(struct gpio_chip *chip, unsigned offset)
config = &ts->port_config[offset >> 2];
+ if (ts->input_pullup_active & BIT(offset))
+ pin_config = PIN_CONFIG_IN_PULLUP;
+ else
+ pin_config = PIN_CONFIG_IN_WO_PULLUP;
+
mutex_lock(&ts->lock);
- /* Standard GPIO API doesn't support pull-ups, has to be extended.
- * Hard-coding no pollup for now. */
*config = (*config & ~(PIN_CONFIG_MASK << offset_bits))
- | (PIN_CONFIG_IN_WO_PULLUP << offset_bits);
+ | (pin_config << offset_bits);
ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);
@@ -177,6 +180,7 @@ int __devinit __max730x_probe(struct max7301 *ts)
/* Power up the chip and disable IRQ output */
ts->write(dev, 0x04, 0x01);
+ ts->input_pullup_active = pdata->input_pullup_active;
ts->chip.label = dev->driver->name;
ts->chip.direction_input = max7301_direction_input;
@@ -191,13 +195,17 @@ int __devinit __max730x_probe(struct max7301 *ts)
ts->chip.owner = THIS_MODULE;
/*
- * tristate all pins in hardware and cache the
+ * initialize pullups according to platform data and cache the
* register values for later use.
*/
for (i = 1; i < 8; i++) {
int j;
- /* 0xAA means input with internal pullup disabled */
- ts->write(dev, 0x08 + i, 0xAA);
+ /*
+ * initialize port_config with "0xAA", which means
+ * input with internal pullup disabled. This is needed
+ * to avoid writing zeros (in the inner for loop),
+ * which is not allowed according to the datasheet.
+ */
ts->port_config[i] = 0xAA;
for (j = 0; j < 4; j++) {
int offset = (i - 1) * 4 + j;
diff --git a/include/linux/spi/max7301.h b/include/linux/spi/max7301.h
index 34af0a3..bcaa2f7 100644
--- a/include/linux/spi/max7301.h
+++ b/include/linux/spi/max7301.h
@@ -11,6 +11,7 @@ struct max7301 {
struct mutex lock;
u8 port_config[8]; /* field 0 is unused */
u32 out_level; /* cached output levels */
+ u32 input_pullup_active;
struct gpio_chip chip;
struct device *dev;
int (*write)(struct device *dev, unsigned int reg, unsigned int val);
@@ -20,6 +21,13 @@ struct max7301 {
struct max7301_platform_data {
/* number assigned to the first GPIO */
unsigned base;
+ /*
+ * bitmask controlling the pullup configuration,
+ *
+ * _note_ the 4 lowest bits are unused, because the first 4
+ * ports of the controller are not used, too.
+ */
+ u32 input_pullup_active;
};
extern int __max730x_remove(struct device *dev);