diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/basic_mmio_gpio.c | 90 |
1 files changed, 59 insertions, 31 deletions
diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c index 90f7f8930d5..728bc67ee08 100644 --- a/drivers/gpio/basic_mmio_gpio.c +++ b/drivers/gpio/basic_mmio_gpio.c @@ -161,14 +161,6 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) unsigned long mask = bgc->pin2mask(bgc, gpio); unsigned long flags; - if (bgc->reg_set) { - if (val) - bgc->write_reg(bgc->reg_set, mask); - else - bgc->write_reg(bgc->reg_clr, mask); - return; - } - spin_lock_irqsave(&bgc->lock, flags); if (val) @@ -181,6 +173,18 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val) spin_unlock_irqrestore(&bgc->lock, flags); } +static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio, + int val) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + unsigned long mask = bgc->pin2mask(bgc, gpio); + + if (val) + bgc->write_reg(bgc->reg_set, mask); + else + bgc->write_reg(bgc->reg_clr, mask); +} + static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) { return 0; @@ -188,7 +192,8 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val) { - bgpio_set(gc, gpio, val); + gc->set(gc, gpio, val); + return 0; } @@ -238,18 +243,25 @@ static int bgpio_setup_accessors(struct platform_device *pdev, return 0; } -static int __devinit bgpio_probe(struct platform_device *pdev) +/* + * Create the device and allocate the resources. For setting GPIO's there are + * two supported configurations: + * + * - single output register resource (named "dat"). + * - set/clear pair (named "set" and "clr"). + * + * For the single output register, this drives a 1 by setting a bit and a zero + * 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. + */ +static int bgpio_setup_io(struct platform_device *pdev, + struct bgpio_chip *bgc) { - struct device *dev = &pdev->dev; - struct bgpio_pdata *pdata = dev_get_platdata(dev); - struct bgpio_chip *bgc; - struct resource *res_dat; struct resource *res_set; struct resource *res_clr; + struct resource *res_dat; resource_size_t dat_sz; - int bits; - int ret; - int ngpio; res_dat = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat"); if (!res_dat) @@ -259,16 +271,11 @@ static int __devinit bgpio_probe(struct platform_device *pdev) if (!is_power_of_2(dat_sz)) return -EINVAL; - bits = dat_sz * 8; - ngpio = bits; - if (bits > BITS_PER_LONG) + bgc->bits = dat_sz * 8; + if (bgc->bits > BITS_PER_LONG) return -EINVAL; - bgc = devm_kzalloc(dev, sizeof(*bgc), GFP_KERNEL); - if (!bgc) - return -ENOMEM; - - bgc->reg_dat = bgpio_request_and_map(dev, res_dat); + bgc->reg_dat = bgpio_request_and_map(&pdev->dev, res_dat); if (!bgc->reg_dat) return -ENOMEM; @@ -276,19 +283,41 @@ static int __devinit bgpio_probe(struct platform_device *pdev) res_clr = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clr"); if (res_set && res_clr) { if (resource_size(res_set) != resource_size(res_clr) || - resource_size(res_set) != dat_sz) + resource_size(res_set) != resource_size(res_dat)) return -EINVAL; - bgc->reg_set = bgpio_request_and_map(dev, res_set); - bgc->reg_clr = bgpio_request_and_map(dev, res_clr); + bgc->reg_set = bgpio_request_and_map(&pdev->dev, res_set); + bgc->reg_clr = bgpio_request_and_map(&pdev->dev, res_clr); if (!bgc->reg_set || !bgc->reg_clr) return -ENOMEM; + + bgc->gc.set = bgpio_set_with_clear; } else if (res_set || res_clr) { return -EINVAL; + } else { + bgc->gc.set = bgpio_set; } - spin_lock_init(&bgc->lock); + return 0; +} + +static int __devinit bgpio_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct bgpio_pdata *pdata = dev_get_platdata(dev); + struct bgpio_chip *bgc; + int ret; + int ngpio; + + bgc = devm_kzalloc(dev, sizeof(*bgc), GFP_KERNEL); + if (!bgc) + return -ENOMEM; + + ret = bgpio_setup_io(pdev, bgc); + if (ret) + return ret; + ngpio = bgc->bits; if (pdata) { bgc->gc.base = pdata->base; if (pdata->ngpio > 0) @@ -297,18 +326,17 @@ static int __devinit bgpio_probe(struct platform_device *pdev) bgc->gc.base = -1; } - bgc->bits = bits; ret = bgpio_setup_accessors(pdev, bgc); if (ret) return ret; + spin_lock_init(&bgc->lock); bgc->data = bgc->read_reg(bgc->reg_dat); 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.set = bgpio_set; bgc->gc.dev = dev; bgc->gc.label = dev_name(dev); |