pinctrl-pxa3xx.c

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/*
 *  linux/drivers/pinctrl/pinctrl-pxa3xx.c
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  publishhed by the Free Software Foundation.
 *
 *  Copyright (C) 2011, Marvell Technology Group Ltd.
 *
 *  Author: Haojian Zhuang <[email protected]>
 *
 */

#include <linux/module.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "pinctrl-pxa3xx.h"

static struct pinctrl_gpio_range pxa3xx_pinctrl_gpio_range = {
    .name       = "PXA3xx GPIO",
    .id     = 0,
    .base       = 0,
    .pin_base   = 0,
};

static int pxa3xx_get_groups_count(struct pinctrl_dev *pctrldev)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);

    return info->num_grps;
}

static const char *pxa3xx_get_group_name(struct pinctrl_dev *pctrldev,
                     unsigned selector)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);

    return info->grps[selector].name;
}

static int pxa3xx_get_group_pins(struct pinctrl_dev *pctrldev,
                 unsigned selector,
                 const unsigned **pins,
                 unsigned *num_pins)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);

    *pins = info->grps[selector].pins;
    *num_pins = info->grps[selector].npins;
    return 0;
}

static struct pinctrl_ops pxa3xx_pctrl_ops = {
    .get_groups_count = pxa3xx_get_groups_count,
    .get_group_name = pxa3xx_get_group_name,
    .get_group_pins = pxa3xx_get_group_pins,
};

static int pxa3xx_pmx_get_funcs_count(struct pinctrl_dev *pctrldev)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);

    return info->num_funcs;
}

static const char *pxa3xx_pmx_get_func_name(struct pinctrl_dev *pctrldev,
                        unsigned func)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
    return info->funcs[func].name;
}

static int pxa3xx_pmx_get_groups(struct pinctrl_dev *pctrldev, unsigned func,
                 const char * const **groups,
                 unsigned * const num_groups)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
    *groups = info->funcs[func].groups;
    *num_groups = info->funcs[func].num_groups;
    return 0;
}

/* Return function number. If failure, return negative value. */
static int match_mux(struct pxa3xx_mfp_pin *mfp, unsigned mux)
{
    int i;
    for (i = 0; i < PXA3xx_MAX_MUX; i++) {
        if (mfp->func[i] == mux)
            break;
    }
    if (i >= PXA3xx_MAX_MUX)
        return -EINVAL;
    return i;
}

/* check whether current pin configuration is valid. Negative for failure */
static int match_group_mux(struct pxa3xx_pin_group *grp,
               struct pxa3xx_pinmux_info *info,
               unsigned mux)
{
    int i, pin, ret = 0;
    for (i = 0; i < grp->npins; i++) {
        pin = grp->pins[i];
        ret = match_mux(&info->mfp[pin], mux);
        if (ret < 0) {
            dev_err(info->dev, "Can't find mux %d on pin%d\n",
                mux, pin);
            break;
        }
    }
    return ret;
}

static int pxa3xx_pmx_enable(struct pinctrl_dev *pctrldev, unsigned func,
                 unsigned group)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
    struct pxa3xx_pin_group *pin_grp = &info->grps[group];
    unsigned int data;
    int i, mfpr, pin, pin_func;

    if (!pin_grp->npins ||
        (match_group_mux(pin_grp, info, pin_grp->mux) < 0)) {
        dev_err(info->dev, "Failed to set the pin group: %d\n", group);
        return -EINVAL;
    }
    for (i = 0; i < pin_grp->npins; i++) {
        pin = pin_grp->pins[i];
        pin_func = match_mux(&info->mfp[pin], pin_grp->mux);
        mfpr = info->mfp[pin].mfpr;
        data = readl_relaxed(info->virt_base + mfpr);
        data &= ~MFPR_FUNC_MASK;
        data |= pin_func;
        writel_relaxed(data, info->virt_base + mfpr);
    }
    return 0;
}

static int pxa3xx_pmx_request_gpio(struct pinctrl_dev *pctrldev,
                   struct pinctrl_gpio_range *range,
                   unsigned pin)
{
    struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
    unsigned int data;
    int pin_func, mfpr;

    pin_func = match_mux(&info->mfp[pin], PXA3xx_MUX_GPIO);
    if (pin_func < 0) {
        dev_err(info->dev, "No GPIO function on pin%d (%s)\n",
            pin, info->pads[pin].name);
        return -EINVAL;
    }
    mfpr = info->mfp[pin].mfpr;
    /* write gpio function into mfpr register */
    data = readl_relaxed(info->virt_base + mfpr) & ~MFPR_FUNC_MASK;
    data |= pin_func;
    writel_relaxed(data, info->virt_base + mfpr);
    return 0;
}

static struct pinmux_ops pxa3xx_pmx_ops = {
    .get_functions_count    = pxa3xx_pmx_get_funcs_count,
    .get_function_name  = pxa3xx_pmx_get_func_name,
    .get_function_groups    = pxa3xx_pmx_get_groups,
    .enable         = pxa3xx_pmx_enable,
    .gpio_request_enable    = pxa3xx_pmx_request_gpio,
};

int pxa3xx_pinctrl_register(struct platform_device *pdev,
                struct pxa3xx_pinmux_info *info)
{
    struct pinctrl_desc *desc;
    struct resource *res;
    int ret = 0;

    if (!info || !info->cputype)
        return -EINVAL;
    desc = info->desc;
    desc->pins = info->pads;
    desc->npins = info->num_pads;
    desc->pctlops = &pxa3xx_pctrl_ops;
    desc->pmxops = &pxa3xx_pmx_ops;
    info->dev = &pdev->dev;
    pxa3xx_pinctrl_gpio_range.npins = info->num_gpio;

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res)
        return -ENOENT;
    info->phy_base = res->start;
    info->phy_size = resource_size(res);
    info->virt_base = ioremap(info->phy_base, info->phy_size);
    if (!info->virt_base)
        return -ENOMEM;
    info->pctrl = pinctrl_register(desc, &pdev->dev, info);
    if (!info->pctrl) {
        dev_err(&pdev->dev, "failed to register PXA pinmux driver\n");
        ret = -EINVAL;
        goto err;
    }
    pinctrl_add_gpio_range(info->pctrl, &pxa3xx_pinctrl_gpio_range);
    platform_set_drvdata(pdev, info);
    return 0;
err:
    iounmap(info->virt_base);
    return ret;
}

int pxa3xx_pinctrl_unregister(struct platform_device *pdev)
{
    struct pxa3xx_pinmux_info *info = platform_get_drvdata(pdev);

    pinctrl_unregister(info->pctrl);
    iounmap(info->virt_base);
    platform_set_drvdata(pdev, NULL);
    return 0;
}

static int __init pxa3xx_pinctrl_init(void)
{
    pr_info("pxa3xx-pinctrl: PXA3xx pinctrl driver initializing\n");
    return 0;
}
core_initcall_sync(pxa3xx_pinctrl_init);

static void __exit pxa3xx_pinctrl_exit(void)
{
}
module_exit(pxa3xx_pinctrl_exit);

MODULE_AUTHOR("Haojian Zhuang <[email protected]>");
MODULE_DESCRIPTION("PXA3xx pin control driver");
MODULE_LICENSE("GPL v2");