Messages in this thread Patch in this message | | | From | Jamie Iles <> | Subject | [RFC PATCH 6/7] basic_mmio_gpio: support different input/output registers | Date | Wed, 6 Apr 2011 12:11:02 +0100 |
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Some controllers have separate input and output registers. For these controllers, allow a register named "in" to be used for reading the value of a GPIO pin.
Signed-off-by: Jamie Iles <jamie@jamieiles.com> Cc: Anton Vorontsov <cbouatmailru@gmail.com> Cc: Grant Likely <grant.likely@secretlab.ca> --- drivers/gpio/basic_mmio_gpio.c | 29 +++++++++++++++++++++++++++-- 1 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c index 500eb6ae..d18a866 100644 --- a/drivers/gpio/basic_mmio_gpio.c +++ b/drivers/gpio/basic_mmio_gpio.c @@ -70,6 +70,7 @@ struct bgpio_chip { void __iomem *reg_dat; void __iomem *reg_set; void __iomem *reg_clr; + void __iomem *reg_in; /* Number of bits (GPIOs): <register width> * 8. */ int bits; @@ -149,13 +150,20 @@ static unsigned long bgpio_pin2mask_be(struct bgpio_chip *bgc, return 1 << (bgc->bits - 1 - pin); } -static int bgpio_get(struct gpio_chip *gc, unsigned int gpio) +static int bgpio_get_dat(struct gpio_chip *gc, unsigned int gpio) { struct bgpio_chip *bgc = to_bgpio_chip(gc); return bgc->read_reg(bgc->reg_dat) & bgc->pin2mask(bgc, gpio); } +static int bgpio_get_in(struct gpio_chip *gc, unsigned int gpio) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + + return bgc->read_reg(bgc->reg_in) & bgc->pin2mask(bgc, gpio); +} + static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) { struct bgpio_chip *bgc = to_bgpio_chip(gc); @@ -255,12 +263,18 @@ static int bgpio_setup_accessors(struct platform_device *pdev, * by clearing a bit. For the set clr pair, this drives a 1 by setting a bit * in the set register and clears it by setting a bit in the clear register. * The configuration is detected by which resources are present. + * + * For getting GPIO values, there are two supported configurations: + * + * - single output/input register resource (named "dat"). + * - separate output/input register resources (named "dat" and "in"). */ static int bgpio_setup_io(struct platform_device *pdev, struct bgpio_chip *bgc) { struct resource *res_set; struct resource *res_clr; + struct resource *res_in; res_set = platform_get_resource_byname(pdev, IORESOURCE_MEM, "set"); res_clr = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clr"); @@ -281,6 +295,16 @@ static int bgpio_setup_io(struct platform_device *pdev, bgc->gc.set = bgpio_set; } + res_in = platform_get_resource_byname(pdev, IORESOURCE_MEM, "in"); + if (res_in) { + bgc->reg_in = bgpio_request_and_map(&pdev->dev, res_in); + if (!bgc->reg_in) + return -ENOMEM; + bgc->gc.get = bgpio_get_in; + } else { + bgc->gc.get = bgpio_get_dat; + } + return 0; } @@ -316,6 +340,8 @@ static int __devinit bgpio_probe(struct platform_device *pdev) if (!bgc->reg_dat) return -ENOMEM; + spin_lock_init(&bgc->lock); + if (pdata) { bgc->gc.base = pdata->base; if (pdata->ngpio > 0) @@ -338,7 +364,6 @@ static int __devinit bgpio_probe(struct platform_device *pdev) bgc->gc.ngpio = ngpio; bgc->gc.direction_input = bgpio_dir_in; bgc->gc.direction_output = bgpio_dir_out; - bgc->gc.get = bgpio_get; bgc->gc.dev = dev; bgc->gc.label = dev_name(dev); -- 1.7.4
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