diff options
Diffstat (limited to 'drivers/gpio/gpio-mmio.c')
-rw-r--r-- | drivers/gpio/gpio-mmio.c | 99 |
1 files changed, 51 insertions, 48 deletions
diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c index 50bdc29591c0..6f904c874678 100644 --- a/drivers/gpio/gpio-mmio.c +++ b/drivers/gpio/gpio-mmio.c @@ -134,17 +134,6 @@ static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio) unsigned long pinmask = bgpio_line2mask(gc, gpio); bool dir = !!(gc->bgpio_dir & pinmask); - /* - * If the direction is OUT we read the value from the SET - * register, and if the direction is IN we read the value - * from the DAT register. - * - * If the direction bits are inverted, naturally this gets - * inverted too. - */ - if (gc->bgpio_dir_inverted) - dir = !dir; - if (dir) return !!(gc->read_reg(gc->reg_set) & pinmask); else @@ -164,14 +153,8 @@ static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask, /* Make sure we first clear any bits that are zero when we read the register */ *bits &= ~*mask; - /* Exploit the fact that we know which directions are set */ - if (gc->bgpio_dir_inverted) { - set_mask = *mask & ~gc->bgpio_dir; - get_mask = *mask & gc->bgpio_dir; - } else { - set_mask = *mask & gc->bgpio_dir; - get_mask = *mask & ~gc->bgpio_dir; - } + set_mask = *mask & gc->bgpio_dir; + get_mask = *mask & ~gc->bgpio_dir; if (set_mask) *bits |= gc->read_reg(gc->reg_set) & set_mask; @@ -372,11 +355,12 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) spin_lock_irqsave(&gc->bgpio_lock, flags); - if (gc->bgpio_dir_inverted) - gc->bgpio_dir |= bgpio_line2mask(gc, gpio); - else - gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio); - gc->write_reg(gc->reg_dir, gc->bgpio_dir); + gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio); + + if (gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + if (gc->reg_dir_out) + gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); spin_unlock_irqrestore(&gc->bgpio_lock, flags); @@ -385,11 +369,16 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio) { - /* Return 0 if output, 1 of input */ - if (gc->bgpio_dir_inverted) - return !!(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio)); - else - return !(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio)); + /* Return 0 if output, 1 if input */ + if (gc->bgpio_dir_unreadable) + return !(gc->bgpio_dir & bgpio_line2mask(gc, gpio)); + if (gc->reg_dir_out) + return !(gc->read_reg(gc->reg_dir_out) & bgpio_line2mask(gc, gpio)); + if (gc->reg_dir_in) + return !!(gc->read_reg(gc->reg_dir_in) & bgpio_line2mask(gc, gpio)); + + /* This should not happen */ + return 1; } static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) @@ -400,11 +389,12 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) spin_lock_irqsave(&gc->bgpio_lock, flags); - if (gc->bgpio_dir_inverted) - gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio); - else - gc->bgpio_dir |= bgpio_line2mask(gc, gpio); - gc->write_reg(gc->reg_dir, gc->bgpio_dir); + gc->bgpio_dir |= bgpio_line2mask(gc, gpio); + + if (gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + if (gc->reg_dir_out) + gc->write_reg(gc->reg_dir_out, gc->bgpio_dir); spin_unlock_irqrestore(&gc->bgpio_lock, flags); @@ -537,19 +527,12 @@ static int bgpio_setup_direction(struct gpio_chip *gc, void __iomem *dirin, unsigned long flags) { - if (dirout && dirin) { - return -EINVAL; - } else if (dirout) { - gc->reg_dir = dirout; - gc->direction_output = bgpio_dir_out; - gc->direction_input = bgpio_dir_in; - gc->get_direction = bgpio_get_dir; - } else if (dirin) { - gc->reg_dir = dirin; + if (dirout || dirin) { + gc->reg_dir_out = dirout; + gc->reg_dir_in = dirin; gc->direction_output = bgpio_dir_out; gc->direction_input = bgpio_dir_in; gc->get_direction = bgpio_get_dir; - gc->bgpio_dir_inverted = true; } else { if (flags & BGPIOF_NO_OUTPUT) gc->direction_output = bgpio_dir_out_err; @@ -588,11 +571,11 @@ static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin) * @dirout: MMIO address for the register to set the line as OUTPUT. It is assumed * that setting a line to 1 in this register will turn that line into an * output line. Conversely, setting the line to 0 will turn that line into - * an input. Either this or @dirin can be defined, but never both. + * an input. * @dirin: MMIO address for the register to set this line as INPUT. It is assumed * that setting a line to 1 in this register will turn that line into an * input line. Conversely, setting the line to 0 will turn that line into - * an output. Either this or @dirout can be defined, but never both. + * an output. * @flags: Different flags that will affect the behaviour of the device, such as * endianness etc. */ @@ -634,8 +617,28 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev, if (gc->set == bgpio_set_set && !(flags & BGPIOF_UNREADABLE_REG_SET)) gc->bgpio_data = gc->read_reg(gc->reg_set); - if (gc->reg_dir && !(flags & BGPIOF_UNREADABLE_REG_DIR)) - gc->bgpio_dir = gc->read_reg(gc->reg_dir); + + if (flags & BGPIOF_UNREADABLE_REG_DIR) + gc->bgpio_dir_unreadable = true; + + /* + * Inspect hardware to find initial direction setting. + */ + if ((gc->reg_dir_out || gc->reg_dir_in) && + !(flags & BGPIOF_UNREADABLE_REG_DIR)) { + if (gc->reg_dir_out) + gc->bgpio_dir = gc->read_reg(gc->reg_dir_out); + else if (gc->reg_dir_in) + gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in); + /* + * If we have two direction registers, synchronise + * input setting to output setting, the library + * can not handle a line being input and output at + * the same time. + */ + if (gc->reg_dir_out && gc->reg_dir_in) + gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir); + } return ret; } |