lkml.org 
[lkml]   [2011]   [Apr]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH] gpio: New driver for the Intel 82801 (ICH) GPIO pins
    On Tue, Apr 19, 2011 at 06:08:29PM +0100, Alan Cox wrote:
    > > How about exporting some bus/device-type neutral probe function, like
    > > we do in drivers/ata/pata_platform.c ?
    >
    > Not sure you want to be using resources as the basic currency, nor do you
    > want your generic code doing the request_region stuff. That was a nasty
    > mistake we made in the IDE code.
    >
    > Maybe the platform code should do that bit, but the generic stuff not - in
    > the PCI case the caller will have done pci_request_* itself and chances
    > are several of the resources are the same pci device resource and
    > different offsets so doing request_resource on them will blow up.

    Oh, right. How about this:

    int __devinit bgpio_probe(struct device *dev,
    unsigned long sz,
    void __iomem *dat,
    void __iomem *set,
    void __iomem *clr,
    void __iomem *dirout,
    void __iomem *dirin,
    bool big_endian);

    I.e. PCI driver can now map the whole area with a single ioremap(),
    and then call bgpio_probe(), which will provide accessors and
    common MMIO GPIO registration stuff.

    Not-yet-signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
    ---
    drivers/gpio/Kconfig | 6 +
    drivers/gpio/Makefile | 1 +
    drivers/gpio/basic_mmio_gpio.c | 241 ++++++++++++++++++++++++---------------
    include/linux/basic_mmio_gpio.h | 15 +++
    4 files changed, 171 insertions(+), 92 deletions(-)
    diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
    index 664660e..88dd650 100644
    --- a/drivers/gpio/Kconfig
    +++ b/drivers/gpio/Kconfig
    @@ -70,8 +70,14 @@ config GPIO_MAX730X

    comment "Memory mapped GPIO expanders:"

    +config GPIO_BASIC_MMIO_CORE
    + tristate
    + help
    + Provides core functionality for basic memory-mapped GPIO controllers.
    +
    config GPIO_BASIC_MMIO
    tristate "Basic memory-mapped GPIO controllers support"
    + select GPIO_BASIC_MMIO_CORE
    help
    Say yes here to support basic memory-mapped GPIO controllers.

    diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
    index 3351cf8..1abf916 100644
    --- a/drivers/gpio/Makefile
    +++ b/drivers/gpio/Makefile
    @@ -10,6 +10,7 @@ obj-$(CONFIG_GPIOLIB) += gpiolib.o

    obj-$(CONFIG_GPIO_ADP5520) += adp5520-gpio.o
    obj-$(CONFIG_GPIO_ADP5588) += adp5588-gpio.o
    +obj-$(CONFIG_GPIO_BASIC_MMIO_CORE) += basic_mmio_gpio.o
    obj-$(CONFIG_GPIO_BASIC_MMIO) += basic_mmio_gpio.o
    obj-$(CONFIG_GPIO_LANGWELL) += langwell_gpio.o
    obj-$(CONFIG_GPIO_MAX730X) += max730x.o
    diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c
    index b2ec45f..947734a 100644
    --- a/drivers/gpio/basic_mmio_gpio.c
    +++ b/drivers/gpio/basic_mmio_gpio.c
    @@ -284,20 +284,10 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
    return 0;
    }

    -static void __iomem *bgpio_request_and_map(struct device *dev,
    - struct resource *res)
    +static int bgpio_setup_accessors(struct device *dev,
    + struct bgpio_chip *bgc,
    + bool be)
    {
    - if (!devm_request_mem_region(dev, res->start, resource_size(res),
    - res->name ?: "mmio_gpio"))
    - return NULL;
    -
    - return devm_ioremap(dev, res->start, resource_size(res));
    -}
    -
    -static int bgpio_setup_accessors(struct platform_device *pdev,
    - struct bgpio_chip *bgc)
    -{
    - const struct platform_device_id *platid = platform_get_device_id(pdev);

    switch (bgc->bits) {
    case 8:
    @@ -319,13 +309,11 @@ static int bgpio_setup_accessors(struct platform_device *pdev,
    break;
    #endif /* BITS_PER_LONG >= 64 */
    default:
    - dev_err(&pdev->dev, "unsupported data width %u bits\n",
    - bgc->bits);
    + dev_err(dev, "unsupported data width %u bits\n", bgc->bits);
    return -EINVAL;
    }

    - bgc->pin2mask = strcmp(platid->name, "basic-mmio-gpio-be") ?
    - bgpio_pin2mask : bgpio_pin2mask_be;
    + bgc->pin2mask = be ? bgpio_pin2mask_be : bgpio_pin2mask;

    return 0;
    }
    @@ -352,51 +340,22 @@ static int bgpio_setup_accessors(struct platform_device *pdev,
    * - an input direction register (named "dirin") where a 1 bit indicates
    * the GPIO is an input.
    */
    -static int bgpio_setup_io(struct platform_device *pdev,
    - struct bgpio_chip *bgc)
    +static int bgpio_setup_io(struct bgpio_chip *bgc,
    + void __iomem *dat,
    + void __iomem *set,
    + void __iomem *clr)
    {
    - struct resource *res_set;
    - struct resource *res_clr;
    - struct resource *res_dat;
    - resource_size_t dat_sz;
    -
    - res_dat = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat");
    - if (!res_dat)
    - return -EINVAL;
    -
    - dat_sz = resource_size(res_dat);
    - if (!is_power_of_2(dat_sz))
    - return -EINVAL;
    -
    - bgc->bits = dat_sz * 8;
    - if (bgc->bits > BITS_PER_LONG)
    - return -EINVAL;

    - bgc->reg_dat = bgpio_request_and_map(&pdev->dev, res_dat);
    + bgc->reg_dat = dat;
    if (!bgc->reg_dat)
    - return -ENOMEM;
    -
    - res_set = platform_get_resource_byname(pdev, IORESOURCE_MEM, "set");
    - 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) != resource_size(res_dat))
    - return -EINVAL;
    -
    - 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;
    + return -EINVAL;

    + if (set && clr) {
    + bgc->reg_set = set;
    + bgc->reg_clr = clr;
    bgc->gc.set = bgpio_set_with_clear;
    - } else if (res_set && !res_clr) {
    - if (resource_size(res_set) != resource_size(res_dat))
    - return -EINVAL;
    -
    - bgc->reg_set = bgpio_request_and_map(&pdev->dev, res_set);
    - if (!bgc->reg_set)
    - return -ENOMEM;
    -
    + } else if (set && !clr) {
    + bgc->reg_set = set;
    bgc->gc.set = bgpio_set_set;
    } else {
    bgc->gc.set = bgpio_set;
    @@ -407,27 +366,18 @@ static int bgpio_setup_io(struct platform_device *pdev,
    return 0;
    }

    -static int bgpio_setup_direction(struct platform_device *pdev,
    - struct bgpio_chip *bgc)
    +static int bgpio_setup_direction(struct bgpio_chip *bgc,
    + void __iomem *dirout,
    + void __iomem *dirin)
    {
    - struct resource *res_dirout;
    - struct resource *res_dirin;
    -
    - res_dirout = platform_get_resource_byname(pdev, IORESOURCE_MEM,
    - "dirout");
    - res_dirin = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dirin");
    - if (res_dirout && res_dirin) {
    + if (dirout && dirin) {
    return -EINVAL;
    - } else if (res_dirout) {
    - bgc->reg_dir = bgpio_request_and_map(&pdev->dev, res_dirout);
    - if (!bgc->reg_dir)
    - return -ENOMEM;
    + } else if (dirout) {
    + bgc->reg_dir = dirout;
    bgc->gc.direction_output = bgpio_dir_out;
    bgc->gc.direction_input = bgpio_dir_in;
    - } else if (res_dirin) {
    - bgc->reg_dir = bgpio_request_and_map(&pdev->dev, res_dirin);
    - if (!bgc->reg_dir)
    - return -ENOMEM;
    + } else if (dirin) {
    + bgc->reg_dir = dirin;
    bgc->gc.direction_output = bgpio_dir_out_inv;
    bgc->gc.direction_input = bgpio_dir_in_inv;
    } else {
    @@ -438,9 +388,23 @@ static int bgpio_setup_direction(struct platform_device *pdev,
    return 0;
    }

    -static int __devinit bgpio_probe(struct platform_device *pdev)
    +int __devexit bgpio_remove(struct device *dev)
    +{
    + struct bgpio_chip *bgc = dev_get_drvdata(dev);
    +
    + return gpiochip_remove(&bgc->gc);
    +}
    +EXPORT_SYMBOL_GPL(bgpio_remove);
    +
    +int __devinit bgpio_probe(struct device *dev,
    + unsigned long sz,
    + void __iomem *dat,
    + void __iomem *set,
    + void __iomem *clr,
    + void __iomem *dirout,
    + void __iomem *dirin,
    + bool big_endian)
    {
    - struct device *dev = &pdev->dev;
    struct bgpio_pdata *pdata = dev_get_platdata(dev);
    struct bgpio_chip *bgc;
    int ret;
    @@ -450,9 +414,16 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
    if (!bgc)
    return -ENOMEM;

    - ret = bgpio_setup_io(pdev, bgc);
    - if (ret)
    - return ret;
    + if (!is_power_of_2(sz))
    + return -EINVAL;
    +
    + bgc->bits = sz * 8;
    + if (bgc->bits > BITS_PER_LONG)
    + return -EINVAL;
    +
    + spin_lock_init(&bgc->lock);
    + bgc->gc.dev = dev;
    + bgc->gc.label = dev_name(dev);

    ngpio = bgc->bits;
    if (pdata) {
    @@ -463,22 +434,23 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
    bgc->gc.base = -1;
    }

    - ret = bgpio_setup_accessors(pdev, bgc);
    + bgc->gc.ngpio = ngpio;
    +
    + ret = bgpio_setup_io(bgc, dat, set, clr);
    if (ret)
    return ret;

    - spin_lock_init(&bgc->lock);
    - ret = bgpio_setup_direction(pdev, bgc);
    + ret = bgpio_setup_accessors(dev, bgc, big_endian);
    if (ret)
    return ret;

    - bgc->data = bgc->read_reg(bgc->reg_dat);
    + ret = bgpio_setup_direction(bgc, dirout, dirin);
    + if (ret)
    + return ret;

    - bgc->gc.ngpio = ngpio;
    - bgc->gc.dev = dev;
    - bgc->gc.label = dev_name(dev);
    + bgc->data = bgc->read_reg(bgc->reg_dat);

    - platform_set_drvdata(pdev, bgc);
    + dev_set_drvdata(dev, bgc);

    ret = gpiochip_add(&bgc->gc);
    if (ret)
    @@ -486,12 +458,95 @@ static int __devinit bgpio_probe(struct platform_device *pdev)

    return ret;
    }
    +EXPORT_SYMBOL_GPL(bgpio_probe);

    -static int __devexit bgpio_remove(struct platform_device *pdev)
    +#ifdef CONFIG_GPIO_BASIC_MMIO
    +
    +static void __iomem *bgpio_map(struct platform_device *pdev,
    + const char *name,
    + resource_size_t sane_sz,
    + int *err)
    {
    - struct bgpio_chip *bgc = platform_get_drvdata(pdev);
    + struct device *dev = &pdev->dev;
    + struct resource *r;
    + resource_size_t start;
    + resource_size_t sz;
    + void __iomem *ret;

    - return gpiochip_remove(&bgc->gc);
    + *err = 0;
    +
    + r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
    + if (!r)
    + return NULL;
    +
    + sz = resource_size(r);
    + if (sz != sane_sz) {
    + *err = -EINVAL;
    + return NULL;
    + }
    +
    + start = r->start;
    + if (!devm_request_mem_region(dev, start, sz, r->name)) {
    + *err = -EBUSY;
    + return NULL;
    + }
    +
    + ret = devm_ioremap(dev, start, sz);
    + if (!ret) {
    + *err = -ENOMEM;
    + return NULL;
    + }
    +
    + return ret;
    +}
    +
    +static int __devinit bgpio_pdev_probe(struct platform_device *pdev)
    +{
    + struct device *dev = &pdev->dev;
    + struct resource *r;
    + void __iomem *dat;
    + void __iomem *set;
    + void __iomem *clr;
    + void __iomem *dirout;
    + void __iomem *dirin;
    + unsigned long sz;
    + bool be;
    + int err;
    +
    + r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat");
    + if (!r)
    + return -EINVAL;
    +
    + sz = resource_size(r);
    +
    + dat = bgpio_map(pdev, "dat", sz, &err);
    + if (!dat)
    + return err ? err : -EINVAL;
    +
    + set = bgpio_map(pdev, "set", sz, &err);
    + if (err)
    + return err;
    +
    + clr = bgpio_map(pdev, "clr", sz, &err);
    + if (err)
    + return err;
    +
    + dirout = bgpio_map(pdev, "dirout", sz, &err);
    + if (err)
    + return err;
    +
    + dirin = bgpio_map(pdev, "dirin", sz, &err);
    + if (err)
    + return err;
    +
    + be = !strcmp(platform_get_device_id(pdev)->name, "basic-mmio-gpio-be");
    +
    + return bgpio_probe(dev, sz, dat, set, clr, dirout, dirin, be);
    +}
    +
    +static int __devexit bgpio_pdev_remove(struct platform_device *pdev)
    +{
    + return bgpio_remove(&pdev->dev);
    }

    static const struct platform_device_id bgpio_id_table[] = {
    @@ -506,8 +561,8 @@ static struct platform_driver bgpio_driver = {
    .name = "basic-mmio-gpio",
    },
    .id_table = bgpio_id_table,
    - .probe = bgpio_probe,
    - .remove = __devexit_p(bgpio_remove),
    + .probe = bgpio_pdev_probe,
    + .remove = __devexit_p(bgpio_pdev_remove),
    };

    static int __init bgpio_init(void)
    @@ -522,6 +577,8 @@ static void __exit bgpio_exit(void)
    }
    module_exit(bgpio_exit);

    +#endif /* CONFIG_GPIO_BASIC_MMIO */
    +
    MODULE_DESCRIPTION("Driver for basic memory-mapped GPIO controllers");
    MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>");
    MODULE_LICENSE("GPL");
    diff --git a/include/linux/basic_mmio_gpio.h b/include/linux/basic_mmio_gpio.h
    index f23ec73..f3a27e4 100644
    --- a/include/linux/basic_mmio_gpio.h
    +++ b/include/linux/basic_mmio_gpio.h
    @@ -13,9 +13,24 @@
    #ifndef __BASIC_MMIO_GPIO_H
    #define __BASIC_MMIO_GPIO_H

    +#include <linux/types.h>
    +#include <linux/compiler.h>
    +
    struct bgpio_pdata {
    int base;
    int ngpio;
    };

    +struct device;
    +
    +int __devexit bgpio_remove(struct device *dev);
    +int __devinit bgpio_probe(struct device *dev,
    + unsigned long sz,
    + void __iomem *dat,
    + void __iomem *set,
    + void __iomem *clr,
    + void __iomem *dirout,
    + void __iomem *dirin,
    + bool big_endian);
    +
    #endif /* __BASIC_MMIO_GPIO_H */
    --
    1.7.4.1


    \
     
     \ /
      Last update: 2011-04-19 22:33    [from the cache]
    ©2003-2014 Jasper Spaans. Advertise on this site