diff --git a/drivers/gpio/max730x.c b/drivers/gpio/max730x.c index 7696a5625d58..94ce773f95f8 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 34af0a3477bf..bcaa2f762cc1 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);