pinctrl: tegra: Add complete device tree support

Implement pinctrl_ops dt_node_to_map() and dt_free_map(). These allow
complete specification of the desired pinmux configuration using device
tree.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 205 insertions, 0 deletions

diff --git a/drivers/pinctrl/pinctrl-tegra.c b/drivers/pinctrl/pinctrl-tegra.c
index 41311a2a4256..2c98fba01ca5 100644
--- a/drivers/pinctrl/pinctrl-tegra.c
+++ b/drivers/pinctrl/pinctrl-tegra.c
@@ -23,9 +23,11 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
+#include <linux/pinctrl/machine.h>
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/pinctrl/pinmux.h>
 #include <linux/pinctrl/pinconf.h>
+#include <linux/slab.h>
 
 #include <mach/pinconf-tegra.h>
 
@@ -88,11 +90,214 @@ static void tegra_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
         seq_printf(s, " " DRIVER_NAME);
 }
 
+static int reserve_map(struct pinctrl_map **map, unsigned *reserved_maps,
+                       unsigned *num_maps, unsigned reserve)
+{
+        unsigned old_num = *reserved_maps;
+        unsigned new_num = *num_maps + reserve;
+        struct pinctrl_map *new_map;
+
+        if (old_num >= new_num)
+                return 0;
+
+        new_map = krealloc(*map, sizeof(*new_map) * new_num, GFP_KERNEL);
+        if (!new_map)
+                return -ENOMEM;
+
+        memset(new_map + old_num, 0, (new_num - old_num) * sizeof(*new_map));
+
+        *map = new_map;
+        *reserved_maps = new_num;
+
+        return 0;
+}
+
+static int add_map_mux(struct pinctrl_map **map, unsigned *reserved_maps,
+                       unsigned *num_maps, const char *group,
+                       const char *function)
+{
+        if (*num_maps == *reserved_maps)
+                return -ENOSPC;
+
+        (*map)[*num_maps].type = PIN_MAP_TYPE_MUX_GROUP;
+        (*map)[*num_maps].data.mux.group = group;
+        (*map)[*num_maps].data.mux.function = function;
+        (*num_maps)++;
+
+        return 0;
+}
+
+static int add_map_configs(struct pinctrl_map **map, unsigned *reserved_maps,
+                           unsigned *num_maps, const char *group,
+                           unsigned long *configs, unsigned num_configs)
+{
+        unsigned long *dup_configs;
+
+        if (*num_maps == *reserved_maps)
+                return -ENOSPC;
+
+        dup_configs = kmemdup(configs, num_configs * sizeof(*dup_configs),
+                              GFP_KERNEL);
+        if (!dup_configs)
+                return -ENOMEM;
+
+        (*map)[*num_maps].type = PIN_MAP_TYPE_CONFIGS_GROUP;
+        (*map)[*num_maps].data.configs.group_or_pin = group;
+        (*map)[*num_maps].data.configs.configs = dup_configs;
+        (*map)[*num_maps].data.configs.num_configs = num_configs;
+        (*num_maps)++;
+
+        return 0;
+}
+
+static int add_config(unsigned long **configs, unsigned *num_configs,
+                      unsigned long config)
+{
+        unsigned old_num = *num_configs;
+        unsigned new_num = old_num + 1;
+        unsigned long *new_configs;
+
+        new_configs = krealloc(*configs, sizeof(*new_configs) * new_num,
+                               GFP_KERNEL);
+        if (!new_configs)
+                return -ENOMEM;
+
+        new_configs[old_num] = config;
+
+        *configs = new_configs;
+        *num_configs = new_num;
+
+        return 0;
+}
+
+void tegra_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
+                               struct pinctrl_map *map, unsigned num_maps)
+{
+        int i;
+
+        for (i = 0; i < num_maps; i++)
+                if (map[i].type == PIN_MAP_TYPE_CONFIGS_GROUP)
+                        kfree(map[i].data.configs.configs);
+
+        kfree(map);
+}
+
+static const struct cfg_param {
+        const char *property;
+        enum tegra_pinconf_param param;
+} cfg_params[] = {
+        {"nvidia,pull",                 TEGRA_PINCONF_PARAM_PULL},
+        {"nvidia,tristate",             TEGRA_PINCONF_PARAM_TRISTATE},
+        {"nvidia,enable-input",         TEGRA_PINCONF_PARAM_ENABLE_INPUT},
+        {"nvidia,open-drain",           TEGRA_PINCONF_PARAM_OPEN_DRAIN},
+        {"nvidia,lock",                 TEGRA_PINCONF_PARAM_LOCK},
+        {"nvidia,io-reset",             TEGRA_PINCONF_PARAM_IORESET},
+        {"nvidia,high-speed-mode",      TEGRA_PINCONF_PARAM_HIGH_SPEED_MODE},
+        {"nvidia,schmitt",              TEGRA_PINCONF_PARAM_SCHMITT},
+        {"nvidia,low-power-mode",       TEGRA_PINCONF_PARAM_LOW_POWER_MODE},
+        {"nvidia,pull-down-strength",   TEGRA_PINCONF_PARAM_DRIVE_DOWN_STRENGTH},
+        {"nvidia,pull-up-strength",     TEGRA_PINCONF_PARAM_DRIVE_UP_STRENGTH},
+        {"nvidia,slew-rate-falling",    TEGRA_PINCONF_PARAM_SLEW_RATE_FALLING},
+        {"nvidia,slew-rate-rising",     TEGRA_PINCONF_PARAM_SLEW_RATE_RISING},
+};
+
+int tegra_pinctrl_dt_subnode_to_map(struct device_node *np,
+                                    struct pinctrl_map **map,
+                                    unsigned *reserved_maps,
+                                    unsigned *num_maps)
+{
+        int ret, i;
+        const char *function;
+        u32 val;
+        unsigned long config;
+        unsigned long *configs = NULL;
+        unsigned num_configs = 0;
+        unsigned reserve;
+        struct property *prop;
+        const char *group;
+
+        ret = of_property_read_string(np, "nvidia,function", &function);
+        if (ret < 0)
+                function = NULL;
+
+        for (i = 0; i < ARRAY_SIZE(cfg_params); i++) {
+                ret = of_property_read_u32(np, cfg_params[i].property, &val);
+                if (!ret) {
+                        config = TEGRA_PINCONF_PACK(cfg_params[i].param, val);
+                        ret = add_config(&configs, &num_configs, config);
+                        if (ret < 0)
+                                goto exit;
+                }
+        }
+
+        reserve = 0;
+        if (function != NULL)
+                reserve++;
+        if (num_configs)
+                reserve++;
+        ret = of_property_count_strings(np, "nvidia,pins");
+        if (ret < 0)
+                goto exit;
+        reserve *= ret;
+
+        ret = reserve_map(map, reserved_maps, num_maps, reserve);
+        if (ret < 0)
+                goto exit;
+
+        of_property_for_each_string(np, "nvidia,pins", prop, group) {
+                if (function) {
+                        ret = add_map_mux(map, reserved_maps, num_maps,
+                                          group, function);
+                        if (ret < 0)
+                                goto exit;
+                }
+
+                if (num_configs) {
+                        ret = add_map_configs(map, reserved_maps, num_maps,
+                                              group, configs, num_configs);
+                        if (ret < 0)
+                                goto exit;
+                }
+        }
+
+        ret = 0;
+
+exit:
+        kfree(configs);
+        return ret;
+}
+
+int tegra_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
+                                 struct device_node *np_config,
+                                 struct pinctrl_map **map, unsigned *num_maps)
+{
+        unsigned reserved_maps;
+        struct device_node *np;
+        int ret;
+
+        reserved_maps = 0;
+        *map = NULL;
+        *num_maps = 0;
+
+        for_each_child_of_node(np_config, np) {
+                ret = tegra_pinctrl_dt_subnode_to_map(np, map, &reserved_maps,
+                                                      num_maps);
+                if (ret < 0) {
+                        tegra_pinctrl_dt_free_map(pctldev, *map, *num_maps);
+                        return ret;
+                }
+        }
+
+        return 0;
+}
+
 static struct pinctrl_ops tegra_pinctrl_ops = {
         .get_groups_count = tegra_pinctrl_get_groups_count,
         .get_group_name = tegra_pinctrl_get_group_name,
         .get_group_pins = tegra_pinctrl_get_group_pins,
         .pin_dbg_show = tegra_pinctrl_pin_dbg_show,
+        .dt_node_to_map = tegra_pinctrl_dt_node_to_map,
+        .dt_free_map = tegra_pinctrl_dt_free_map,
 };
 
 static int tegra_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)