pinctrl: New driver for TI DA850/OMAP-L138/AM18XX pinconf

This adds a new driver for pinconf on TI DA850/OMAP-L138/AM18XX. These
SoCs have a separate controller for controlling pullup/pulldown groups.

Signed-off-by: David Lechner <david@lechnology.com>
Reviewed-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 210 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-da850-pupd.c b/drivers/pinctrl/pinctrl-da850-pupd.c
new file mode 100644
index 000000000000..b36a90a3f3e4
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-da850-pupd.c
@@ -0,0 +1,210 @@
+/*
+ * Pinconf driver for TI DA850/OMAP-L138/AM18XX pullup/pulldown groups
+ *
+ * Copyright (C) 2016  David Lechner
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that 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/bitops.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinconf-generic.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/platform_device.h>
+
+#define DA850_PUPD_ENA          0x00
+#define DA850_PUPD_SEL          0x04
+
+struct da850_pupd_data {
+        void __iomem *base;
+        struct pinctrl_desc desc;
+        struct pinctrl_dev *pinctrl;
+};
+
+static const char * const da850_pupd_group_names[] = {
+        "cp0", "cp1", "cp2", "cp3", "cp4", "cp5", "cp6", "cp7",
+        "cp8", "cp9", "cp10", "cp11", "cp12", "cp13", "cp14", "cp15",
+        "cp16", "cp17", "cp18", "cp19", "cp20", "cp21", "cp22", "cp23",
+        "cp24", "cp25", "cp26", "cp27", "cp28", "cp29", "cp30", "cp31",
+};
+
+static int da850_pupd_get_groups_count(struct pinctrl_dev *pctldev)
+{
+        return ARRAY_SIZE(da850_pupd_group_names);
+}
+
+static const char *da850_pupd_get_group_name(struct pinctrl_dev *pctldev,
+                                             unsigned int selector)
+{
+        return da850_pupd_group_names[selector];
+}
+
+static int da850_pupd_get_group_pins(struct pinctrl_dev *pctldev,
+                                     unsigned int selector,
+                                     const unsigned int **pins,
+                                     unsigned int *num_pins)
+{
+        *num_pins = 0;
+
+        return 0;
+}
+
+static const struct pinctrl_ops da850_pupd_pctlops = {
+        .get_groups_count       = da850_pupd_get_groups_count,
+        .get_group_name         = da850_pupd_get_group_name,
+        .get_group_pins         = da850_pupd_get_group_pins,
+        .dt_node_to_map         = pinconf_generic_dt_node_to_map_group,
+        .dt_free_map            = pinconf_generic_dt_free_map,
+};
+
+static int da850_pupd_pin_config_group_get(struct pinctrl_dev *pctldev,
+                                           unsigned int selector,
+                                           unsigned long *config)
+{
+        struct da850_pupd_data *data = pinctrl_dev_get_drvdata(pctldev);
+        enum pin_config_param param = pinconf_to_config_param(*config);
+        u32 val;
+        u16 arg;
+
+        val = readl(data->base + DA850_PUPD_ENA);
+        arg = !!(~val & BIT(selector));
+
+        switch (param) {
+        case PIN_CONFIG_BIAS_DISABLE:
+                break;
+        case PIN_CONFIG_BIAS_PULL_UP:
+        case PIN_CONFIG_BIAS_PULL_DOWN:
+                if (arg) {
+                        /* bias is disabled */
+                        arg = 0;
+                        break;
+                }
+                val = readl(data->base + DA850_PUPD_SEL);
+                if (param == PIN_CONFIG_BIAS_PULL_DOWN)
+                        val = ~val;
+                arg = !!(val & BIT(selector));
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        *config = pinconf_to_config_packed(param, arg);
+
+        return 0;
+}
+
+static int da850_pupd_pin_config_group_set(struct pinctrl_dev *pctldev,
+                                           unsigned int selector,
+                                           unsigned long *configs,
+                                           unsigned int num_configs)
+{
+        struct da850_pupd_data *data = pinctrl_dev_get_drvdata(pctldev);
+        u32 ena, sel;
+        enum pin_config_param param;
+        u16 arg;
+        int i;
+
+        ena = readl(data->base + DA850_PUPD_ENA);
+        sel = readl(data->base + DA850_PUPD_SEL);
+
+        for (i = 0; i < num_configs; i++) {
+                param = pinconf_to_config_param(configs[i]);
+                arg = pinconf_to_config_argument(configs[i]);
+
+                switch (param) {
+                case PIN_CONFIG_BIAS_DISABLE:
+                        ena &= ~BIT(selector);
+                        break;
+                case PIN_CONFIG_BIAS_PULL_UP:
+                        ena |= BIT(selector);
+                        sel |= BIT(selector);
+                        break;
+                case PIN_CONFIG_BIAS_PULL_DOWN:
+                        ena |= BIT(selector);
+                        sel &= ~BIT(selector);
+                        break;
+                default:
+                        return -EINVAL;
+                }
+        }
+
+        writel(sel, data->base + DA850_PUPD_SEL);
+        writel(ena, data->base + DA850_PUPD_ENA);
+
+        return 0;
+}
+
+static const struct pinconf_ops da850_pupd_confops = {
+        .is_generic             = true,
+        .pin_config_group_get   = da850_pupd_pin_config_group_get,
+        .pin_config_group_set   = da850_pupd_pin_config_group_set,
+};
+
+static int da850_pupd_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct da850_pupd_data *data;
+        struct resource *res;
+
+        data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        data->base = devm_ioremap_resource(dev, res);
+        if (IS_ERR(data->base)) {
+                dev_err(dev, "Could not map resource\n");
+                return PTR_ERR(data->base);
+        }
+
+        data->desc.name = dev_name(dev);
+        data->desc.pctlops = &da850_pupd_pctlops;
+        data->desc.confops = &da850_pupd_confops;
+        data->desc.owner = THIS_MODULE;
+
+        data->pinctrl = devm_pinctrl_register(dev, &data->desc, data);
+        if (IS_ERR(data->pinctrl)) {
+                dev_err(dev, "Failed to register pinctrl\n");
+                return PTR_ERR(data->pinctrl);
+        }
+
+        platform_set_drvdata(pdev, data);
+
+        return 0;
+}
+
+static int da850_pupd_remove(struct platform_device *pdev)
+{
+        return 0;
+}
+
+static const struct of_device_id da850_pupd_of_match[] = {
+        { .compatible = "ti,da850-pupd" },
+        { }
+};
+
+static struct platform_driver da850_pupd_driver = {
+        .driver = {
+                .name           = "ti-da850-pupd",
+                .of_match_table = da850_pupd_of_match,
+        },
+        .probe  = da850_pupd_probe,
+        .remove = da850_pupd_remove,
+};
+module_platform_driver(da850_pupd_driver);
+
+MODULE_AUTHOR("David Lechner <david@lechnology.com>");
+MODULE_DESCRIPTION("TI DA850/OMAP-L138/AM18XX pullup/pulldown configuration");
+MODULE_LICENSE("GPL");