pinctrl: add a driver for NVIDIA Tegra

This adds a driver for the Tegra pinmux, and required parameterization
data for Tegra20 and Tegra30.

The driver is initially added with driver name and device tree compatible
value that won't cause this driver to be used. A later change will switch
the pinctrl driver to use the correct values, switch the old pinmux
driver to be disabled, and update all code that uses the old pinmux APIs
to use the new pinctrl APIs.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Olof Johansson <olof@lixom.net>
[squashed "fix case of Tegra30's foo_groups[] arrays"]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 559 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-tegra.c b/drivers/pinctrl/pinctrl-tegra.c
new file mode 100644
index 000000000000..9b329688120c
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-tegra.c
@@ -0,0 +1,559 @@
+/*
+ * Driver for the NVIDIA Tegra pinmux
+ *
+ * Copyright (c) 2011, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Derived from code:
+ * Copyright (C) 2010 Google, Inc.
+ * Copyright (C) 2010 NVIDIA Corporation
+ * Copyright (C) 2009-2011 ST-Ericsson AB
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf.h>
+
+#include <mach/pinconf-tegra.h>
+
+#include "pinctrl-tegra.h"
+
+#define DRIVER_NAME "tegra-pinmux-disabled"
+
+struct tegra_pmx {
+        struct device *dev;
+        struct pinctrl_dev *pctl;
+
+        const struct tegra_pinctrl_soc_data *soc;
+
+        int nbanks;
+        void __iomem **regs;
+};
+
+static inline u32 pmx_readl(struct tegra_pmx *pmx, u32 bank, u32 reg)
+{
+        return readl(pmx->regs[bank] + reg);
+}
+
+static inline void pmx_writel(struct tegra_pmx *pmx, u32 val, u32 bank, u32 reg)
+{
+        writel(val, pmx->regs[bank] + reg);
+}
+
+static int tegra_pinctrl_list_groups(struct pinctrl_dev *pctldev,
+                                     unsigned group)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+        if (group >= pmx->soc->ngroups)
+                return -EINVAL;
+
+        return 0;
+}
+
+static const char *tegra_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
+                                                unsigned group)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+        if (group >= pmx->soc->ngroups)
+                return NULL;
+
+        return pmx->soc->groups[group].name;
+}
+
+static int tegra_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
+                                        unsigned group,
+                                        const unsigned **pins,
+                                        unsigned *num_pins)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+        if (group >= pmx->soc->ngroups)
+                return -EINVAL;
+
+        *pins = pmx->soc->groups[group].pins;
+        *num_pins = pmx->soc->groups[group].npins;
+
+        return 0;
+}
+
+static void tegra_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
+                                       struct seq_file *s,
+                                       unsigned offset)
+{
+        seq_printf(s, " " DRIVER_NAME);
+}
+
+static struct pinctrl_ops tegra_pinctrl_ops = {
+        .list_groups = tegra_pinctrl_list_groups,
+        .get_group_name = tegra_pinctrl_get_group_name,
+        .get_group_pins = tegra_pinctrl_get_group_pins,
+        .pin_dbg_show = tegra_pinctrl_pin_dbg_show,
+};
+
+static int tegra_pinctrl_list_funcs(struct pinctrl_dev *pctldev,
+                                    unsigned function)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+        if (function >= pmx->soc->nfunctions)
+                return -EINVAL;
+
+        return 0;
+}
+
+static const char *tegra_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
+                                               unsigned function)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+        if (function >= pmx->soc->nfunctions)
+                return NULL;
+
+        return pmx->soc->functions[function].name;
+}
+
+static int tegra_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
+                                         unsigned function,
+                                         const char * const **groups,
+                                         unsigned * const num_groups)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+
+        if (function >= pmx->soc->nfunctions)
+                return -EINVAL;
+
+        *groups = pmx->soc->functions[function].groups;
+        *num_groups = pmx->soc->functions[function].ngroups;
+
+        return 0;
+}
+
+static int tegra_pinctrl_enable(struct pinctrl_dev *pctldev, unsigned function,
+                               unsigned group)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+        const struct tegra_pingroup *g;
+        int i;
+        u32 val;
+
+        if (group >= pmx->soc->ngroups)
+                return -EINVAL;
+        g = &pmx->soc->groups[group];
+
+        if (g->mux_reg < 0)
+                return -EINVAL;
+
+        for (i = 0; i < ARRAY_SIZE(g->funcs); i++) {
+                if (g->funcs[i] == function)
+                        break;
+        }
+        if (i == ARRAY_SIZE(g->funcs))
+                return -EINVAL;
+
+        val = pmx_readl(pmx, g->mux_bank, g->mux_reg);
+        val &= ~(0x3 << g->mux_bit);
+        val |= i << g->mux_bit;
+        pmx_writel(pmx, val, g->mux_bank, g->mux_reg);
+
+        return 0;
+}
+
+static void tegra_pinctrl_disable(struct pinctrl_dev *pctldev,
+                                  unsigned function, unsigned group)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+        const struct tegra_pingroup *g;
+        u32 val;
+
+        if (group >= pmx->soc->ngroups)
+                return;
+        g = &pmx->soc->groups[group];
+
+        if (g->mux_reg < 0)
+                return;
+
+        val = pmx_readl(pmx, g->mux_bank, g->mux_reg);
+        val &= ~(0x3 << g->mux_bit);
+        val |= g->func_safe << g->mux_bit;
+        pmx_writel(pmx, val, g->mux_bank, g->mux_reg);
+}
+
+static struct pinmux_ops tegra_pinmux_ops = {
+        .list_functions = tegra_pinctrl_list_funcs,
+        .get_function_name = tegra_pinctrl_get_func_name,
+        .get_function_groups = tegra_pinctrl_get_func_groups,
+        .enable = tegra_pinctrl_enable,
+        .disable = tegra_pinctrl_disable,
+};
+
+static int tegra_pinconf_reg(struct tegra_pmx *pmx,
+                             const struct tegra_pingroup *g,
+                             enum tegra_pinconf_param param,
+                             s8 *bank, s16 *reg, s8 *bit, s8 *width)
+{
+        switch (param) {
+        case TEGRA_PINCONF_PARAM_PULL:
+                *bank = g->pupd_bank;
+                *reg = g->pupd_reg;
+                *bit = g->pupd_bit;
+                *width = 2;
+                break;
+        case TEGRA_PINCONF_PARAM_TRISTATE:
+                *bank = g->tri_bank;
+                *reg = g->tri_reg;
+                *bit = g->tri_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_ENABLE_INPUT:
+                *bank = g->einput_bank;
+                *reg = g->einput_reg;
+                *bit = g->einput_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_OPEN_DRAIN:
+                *bank = g->odrain_bank;
+                *reg = g->odrain_reg;
+                *bit = g->odrain_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_LOCK:
+                *bank = g->lock_bank;
+                *reg = g->lock_reg;
+                *bit = g->lock_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_IORESET:
+                *bank = g->ioreset_bank;
+                *reg = g->ioreset_reg;
+                *bit = g->ioreset_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_HIGH_SPEED_MODE:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->hsm_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_SCHMITT:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->schmitt_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_LOW_POWER_MODE:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->lpmd_bit;
+                *width = 1;
+                break;
+        case TEGRA_PINCONF_PARAM_DRIVE_DOWN_STRENGTH:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->drvdn_bit;
+                *width = g->drvdn_width;
+                break;
+        case TEGRA_PINCONF_PARAM_DRIVE_UP_STRENGTH:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->drvup_bit;
+                *width = g->drvup_width;
+                break;
+        case TEGRA_PINCONF_PARAM_SLEW_RATE_FALLING:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->slwf_bit;
+                *width = g->slwf_width;
+                break;
+        case TEGRA_PINCONF_PARAM_SLEW_RATE_RISING:
+                *bank = g->drv_bank;
+                *reg = g->drv_reg;
+                *bit = g->slwr_bit;
+                *width = g->slwr_width;
+                break;
+        default:
+                dev_err(pmx->dev, "Invalid config param %04x\n", param);
+                return -ENOTSUPP;
+        }
+
+        if (*reg < 0) {
+                dev_err(pmx->dev,
+                        "Config param %04x not supported on group %s\n",
+                        param, g->name);
+                return -ENOTSUPP;
+        }
+
+        return 0;
+}
+
+static int tegra_pinconf_get(struct pinctrl_dev *pctldev,
+                             unsigned pin, unsigned long *config)
+{
+        return -ENOTSUPP;
+}
+
+static int tegra_pinconf_set(struct pinctrl_dev *pctldev,
+                             unsigned pin, unsigned long config)
+{
+        return -ENOTSUPP;
+}
+
+static int tegra_pinconf_group_get(struct pinctrl_dev *pctldev,
+                                   unsigned group, unsigned long *config)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+        enum tegra_pinconf_param param = TEGRA_PINCONF_UNPACK_PARAM(*config);
+        u16 arg;
+        const struct tegra_pingroup *g;
+        int ret;
+        s8 bank, bit, width;
+        s16 reg;
+        u32 val, mask;
+
+        if (group >= pmx->soc->ngroups)
+                return -EINVAL;
+        g = &pmx->soc->groups[group];
+
+        ret = tegra_pinconf_reg(pmx, g, param, &bank, &reg, &bit, &width);
+        if (ret < 0)
+                return ret;
+
+        val = pmx_readl(pmx, bank, reg);
+        mask = (1 << width) - 1;
+        arg = (val >> bit) & mask;
+
+        *config = TEGRA_PINCONF_PACK(param, arg);
+
+        return 0;
+}
+
+static int tegra_pinconf_group_set(struct pinctrl_dev *pctldev,
+                                   unsigned group, unsigned long config)
+{
+        struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+        enum tegra_pinconf_param param = TEGRA_PINCONF_UNPACK_PARAM(config);
+        u16 arg = TEGRA_PINCONF_UNPACK_ARG(config);
+        const struct tegra_pingroup *g;
+        int ret;
+        s8 bank, bit, width;
+        s16 reg;
+        u32 val, mask;
+
+        if (group >= pmx->soc->ngroups)
+                return -EINVAL;
+        g = &pmx->soc->groups[group];
+
+        ret = tegra_pinconf_reg(pmx, g, param, &bank, &reg, &bit, &width);
+        if (ret < 0)
+                return ret;
+
+        val = pmx_readl(pmx, bank, reg);
+
+        /* LOCK can't be cleared */
+        if (param == TEGRA_PINCONF_PARAM_LOCK) {
+                if ((val & BIT(bit)) && !arg)
+                        return -EINVAL;
+        }
+
+        /* Special-case Boolean values; allow any non-zero as true */
+        if (width == 1)
+                arg = !!arg;
+
+        /* Range-check user-supplied value */
+        mask = (1 << width) - 1;
+        if (arg & ~mask)
+                return -EINVAL;
+
+        /* Update register */
+        val &= ~(mask << bit);
+        val |= arg << bit;
+        pmx_writel(pmx, val, bank, reg);
+
+        return 0;
+}
+
+static void tegra_pinconf_dbg_show(struct pinctrl_dev *pctldev,
+                                   struct seq_file *s, unsigned offset)
+{
+}
+
+static void tegra_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
+                                         struct seq_file *s, unsigned selector)
+{
+}
+
+struct pinconf_ops tegra_pinconf_ops = {
+        .pin_config_get = tegra_pinconf_get,
+        .pin_config_set = tegra_pinconf_set,
+        .pin_config_group_get = tegra_pinconf_group_get,
+        .pin_config_group_set = tegra_pinconf_group_set,
+        .pin_config_dbg_show = tegra_pinconf_dbg_show,
+        .pin_config_group_dbg_show = tegra_pinconf_group_dbg_show,
+};
+
+static struct pinctrl_gpio_range tegra_pinctrl_gpio_range = {
+        .name = "Tegra GPIOs",
+        .id = 0,
+        .base = 0,
+};
+
+static struct pinctrl_desc tegra_pinctrl_desc = {
+        .name = DRIVER_NAME,
+        .pctlops = &tegra_pinctrl_ops,
+        .pmxops = &tegra_pinmux_ops,
+        .confops = &tegra_pinconf_ops,
+        .owner = THIS_MODULE,
+};
+
+static struct of_device_id tegra_pinctrl_of_match[] __devinitdata = {
+#ifdef CONFIG_PINCTRL_TEGRA20
+        {
+                .compatible = "nvidia,tegra20-pinmux-disabled",
+                .data = tegra20_pinctrl_init,
+        },
+#endif
+#ifdef CONFIG_PINCTRL_TEGRA30
+        {
+                .compatible = "nvidia,tegra30-pinmux-disabled",
+                .data = tegra30_pinctrl_init,
+        },
+#endif
+        {},
+};
+
+static int __devinit tegra_pinctrl_probe(struct platform_device *pdev)
+{
+        const struct of_device_id *match;
+        tegra_pinctrl_soc_initf initf = NULL;
+        struct tegra_pmx *pmx;
+        struct resource *res;
+        int i;
+
+        match = of_match_device(tegra_pinctrl_of_match, &pdev->dev);
+        if (match)
+                initf = (tegra_pinctrl_soc_initf)match->data;
+#ifdef CONFIG_PINCTRL_TEGRA20
+        if (!initf)
+                initf = tegra20_pinctrl_init;
+#endif
+        if (!initf) {
+                dev_err(&pdev->dev,
+                        "Could not determine SoC-specific init func\n");
+                return -EINVAL;
+        }
+
+        pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
+        if (!pmx) {
+                dev_err(&pdev->dev, "Can't alloc tegra_pmx\n");
+                return -ENOMEM;
+        }
+        pmx->dev = &pdev->dev;
+
+        (*initf)(&pmx->soc);
+
+        tegra_pinctrl_gpio_range.npins = pmx->soc->ngpios;
+        tegra_pinctrl_desc.pins = pmx->soc->pins;
+        tegra_pinctrl_desc.npins = pmx->soc->npins;
+
+        for (i = 0; ; i++) {
+                res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+                if (!res)
+                        break;
+        }
+        pmx->nbanks = i;
+
+        pmx->regs = devm_kzalloc(&pdev->dev, pmx->nbanks * sizeof(*pmx->regs),
+                                 GFP_KERNEL);
+        if (!pmx->regs) {
+                dev_err(&pdev->dev, "Can't alloc regs pointer\n");
+                return -ENODEV;
+        }
+
+        for (i = 0; i < pmx->nbanks; i++) {
+                res = platform_get_resource(pdev, IORESOURCE_MEM, i);
+                if (!res) {
+                        dev_err(&pdev->dev, "Missing MEM resource\n");
+                        return -ENODEV;
+                }
+
+                if (!devm_request_mem_region(&pdev->dev, res->start,
+                                            resource_size(res),
+                                            dev_name(&pdev->dev))) {
+                        dev_err(&pdev->dev,
+                                "Couldn't request MEM resource %d\n", i);
+                        return -ENODEV;
+                }
+
+                pmx->regs[i] = devm_ioremap(&pdev->dev, res->start,
+                                            resource_size(res));
+                if (!pmx->regs[i]) {
+                        dev_err(&pdev->dev, "Couldn't ioremap regs %d\n", i);
+                        return -ENODEV;
+                }
+        }
+
+        pmx->pctl = pinctrl_register(&tegra_pinctrl_desc, &pdev->dev, pmx);
+        if (IS_ERR(pmx->pctl)) {
+                dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
+                return PTR_ERR(pmx->pctl);
+        }
+
+        pinctrl_add_gpio_range(pmx->pctl, &tegra_pinctrl_gpio_range);
+
+        platform_set_drvdata(pdev, pmx);
+
+        dev_dbg(&pdev->dev, "Probed Tegra pinctrl driver\n");
+
+        return 0;
+}
+
+static int __devexit tegra_pinctrl_remove(struct platform_device *pdev)
+{
+        struct tegra_pmx *pmx = platform_get_drvdata(pdev);
+
+        pinctrl_remove_gpio_range(pmx->pctl, &tegra_pinctrl_gpio_range);
+        pinctrl_unregister(pmx->pctl);
+
+        return 0;
+}
+
+static struct platform_driver tegra_pinctrl_driver = {
+        .driver = {
+                .name = DRIVER_NAME,
+                .owner = THIS_MODULE,
+                .of_match_table = tegra_pinctrl_of_match,
+        },
+        .probe = tegra_pinctrl_probe,
+        .remove = __devexit_p(tegra_pinctrl_remove),
+};
+
+static int __init tegra_pinctrl_init(void)
+{
+        return platform_driver_register(&tegra_pinctrl_driver);
+}
+arch_initcall(tegra_pinctrl_init);
+
+static void __exit tegra_pinctrl_exit(void)
+{
+        platform_driver_unregister(&tegra_pinctrl_driver);
+}
+module_exit(tegra_pinctrl_exit);
+
+MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
+MODULE_DESCRIPTION("NVIDIA Tegra pinctrl driver");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, tegra_pinctrl_of_match);