pinctrl: single: support generic pinconf
authorHaojian Zhuang <haojian.zhuang@linaro.org>
Sun, 17 Feb 2013 11:42:55 +0000 (19:42 +0800)
committerLinus Walleij <linus.walleij@linaro.org>
Thu, 7 Mar 2013 04:27:31 +0000 (05:27 +0100)
Support the operation of generic pinconf. The supported config arguments
are INPUT_SCHMITT, INPUT_SCHMITT_ENABLE, DRIVE_STRENGHT, BIAS_DISABLE,
BIAS_PULLUP, BIAS_PULLDOWN, SLEW_RATE.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
drivers/pinctrl/Kconfig
drivers/pinctrl/pinctrl-single.c

index 34f51d2..5a690ce 100644 (file)
@@ -166,6 +166,7 @@ config PINCTRL_SINGLE
        depends on OF
        select PINMUX
        select PINCONF
+       select GENERIC_PINCONF
        help
          This selects the device tree based generic pinctrl driver.
 
index f9596fe..4cdcf85 100644 (file)
 
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/pinctrl/pinmux.h>
+#include <linux/pinctrl/pinconf-generic.h>
 
 #include "core.h"
+#include "pinconf.h"
 
 #define DRIVER_NAME                    "pinctrl-single"
 #define PCS_MUX_PINS_NAME              "pinctrl-single,pins"
@@ -58,6 +60,33 @@ struct pcs_func_vals {
        unsigned mask;
 };
 
+/**
+ * struct pcs_conf_vals - pinconf parameter, pinconf register offset
+ * and value, enable, disable, mask
+ * @param:     config parameter
+ * @val:       user input bits in the pinconf register
+ * @enable:    enable bits in the pinconf register
+ * @disable:   disable bits in the pinconf register
+ * @mask:      mask bits in the register value
+ */
+struct pcs_conf_vals {
+       enum pin_config_param param;
+       unsigned val;
+       unsigned enable;
+       unsigned disable;
+       unsigned mask;
+};
+
+/**
+ * struct pcs_conf_type - pinconf property name, pinconf param pair
+ * @name:      property name in DTS file
+ * @param:     config parameter
+ */
+struct pcs_conf_type {
+       const char *name;
+       enum pin_config_param param;
+};
+
 /**
  * struct pcs_function - pinctrl function
  * @name:      pinctrl function name
@@ -73,6 +102,8 @@ struct pcs_function {
        unsigned nvals;
        const char **pgnames;
        int npgnames;
+       struct pcs_conf_vals *conf;
+       int nconfs;
        struct list_head node;
 };
 
@@ -131,6 +162,7 @@ struct pcs_name {
  * @fshift:    function register shift
  * @foff:      value to turn mux off
  * @fmax:      max number of functions in fmask
+ * @is_pinconf:        whether supports pinconf
  * @names:     array of register names for pins
  * @pins:      physical pins on the SoC
  * @pgtree:    pingroup index radix tree
@@ -157,6 +189,7 @@ struct pcs_device {
        unsigned foff;
        unsigned fmax;
        bool bits_per_mux;
+       bool is_pinconf;
        struct pcs_name *names;
        struct pcs_data pins;
        struct radix_tree_root pgtree;
@@ -171,6 +204,16 @@ struct pcs_device {
        void (*write)(unsigned val, void __iomem *reg);
 };
 
+static int pcs_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
+                          unsigned long *config);
+static int pcs_pinconf_set(struct pinctrl_dev *pctldev, unsigned pin,
+                          unsigned long config);
+
+static enum pin_config_param pcs_bias[] = {
+       PIN_CONFIG_BIAS_PULL_DOWN,
+       PIN_CONFIG_BIAS_PULL_UP,
+};
+
 /*
  * REVISIT: Reads and writes could eventually use regmap or something
  * generic. But at least on omaps, some mux registers are performance
@@ -342,6 +385,28 @@ static int pcs_get_function_groups(struct pinctrl_dev *pctldev,
        return 0;
 }
 
+static int pcs_get_function(struct pinctrl_dev *pctldev, unsigned pin,
+                           struct pcs_function **func)
+{
+       struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
+       struct pin_desc *pdesc = pin_desc_get(pctldev, pin);
+       const struct pinctrl_setting_mux *setting;
+       unsigned fselector;
+
+       /* If pin is not described in DTS & enabled, mux_setting is NULL. */
+       setting = pdesc->mux_setting;
+       if (!setting)
+               return -ENOTSUPP;
+       fselector = setting->func;
+       *func = radix_tree_lookup(&pcs->ftree, fselector);
+       if (!(*func)) {
+               dev_err(pcs->dev, "%s could not find function%i\n",
+                       __func__, fselector);
+               return -ENOTSUPP;
+       }
+       return 0;
+}
+
 static int pcs_enable(struct pinctrl_dev *pctldev, unsigned fselector,
        unsigned group)
 {
@@ -461,32 +526,191 @@ static const struct pinmux_ops pcs_pinmux_ops = {
        .gpio_request_enable = pcs_request_gpio,
 };
 
+/* Clear BIAS value */
+static void pcs_pinconf_clear_bias(struct pinctrl_dev *pctldev, unsigned pin)
+{
+       unsigned long config;
+       int i;
+       for (i = 0; i < ARRAY_SIZE(pcs_bias); i++) {
+               config = pinconf_to_config_packed(pcs_bias[i], 0);
+               pcs_pinconf_set(pctldev, pin, config);
+       }
+}
+
+/*
+ * Check whether PIN_CONFIG_BIAS_DISABLE is valid.
+ * It's depend on that PULL_DOWN & PULL_UP configs are all invalid.
+ */
+static bool pcs_pinconf_bias_disable(struct pinctrl_dev *pctldev, unsigned pin)
+{
+       unsigned long config;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(pcs_bias); i++) {
+               config = pinconf_to_config_packed(pcs_bias[i], 0);
+               if (!pcs_pinconf_get(pctldev, pin, &config))
+                       goto out;
+       }
+       return true;
+out:
+       return false;
+}
+
 static int pcs_pinconf_get(struct pinctrl_dev *pctldev,
                                unsigned pin, unsigned long *config)
 {
+       struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
+       struct pcs_function *func;
+       enum pin_config_param param;
+       unsigned offset = 0, data = 0, i, j, ret;
+
+       ret = pcs_get_function(pctldev, pin, &func);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < func->nconfs; i++) {
+               param = pinconf_to_config_param(*config);
+               if (param == PIN_CONFIG_BIAS_DISABLE) {
+                       if (pcs_pinconf_bias_disable(pctldev, pin)) {
+                               *config = 0;
+                               return 0;
+                       } else {
+                               return -ENOTSUPP;
+                       }
+               } else if (param != func->conf[i].param) {
+                       continue;
+               }
+
+               offset = pin * (pcs->width / BITS_PER_BYTE);
+               data = pcs->read(pcs->base + offset) & func->conf[i].mask;
+               switch (func->conf[i].param) {
+               /* 4 parameters */
+               case PIN_CONFIG_BIAS_PULL_DOWN:
+               case PIN_CONFIG_BIAS_PULL_UP:
+               case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
+                       if ((data != func->conf[i].enable) ||
+                           (data == func->conf[i].disable))
+                               return -ENOTSUPP;
+                       *config = 0;
+                       break;
+               /* 2 parameters */
+               case PIN_CONFIG_INPUT_SCHMITT:
+                       for (j = 0; j < func->nconfs; j++) {
+                               switch (func->conf[j].param) {
+                               case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
+                                       if (data != func->conf[j].enable)
+                                               return -ENOTSUPP;
+                                       break;
+                               default:
+                                       break;
+                               }
+                       }
+                       *config = data;
+                       break;
+               case PIN_CONFIG_DRIVE_STRENGTH:
+               case PIN_CONFIG_SLEW_RATE:
+               default:
+                       *config = data;
+                       break;
+               }
+               return 0;
+       }
        return -ENOTSUPP;
 }
 
 static int pcs_pinconf_set(struct pinctrl_dev *pctldev,
                                unsigned pin, unsigned long config)
 {
+       struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
+       struct pcs_function *func;
+       unsigned offset = 0, shift = 0, arg = 0, i, data, ret;
+       u16 argument;
+
+       ret = pcs_get_function(pctldev, pin, &func);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < func->nconfs; i++) {
+               if (pinconf_to_config_param(config) == func->conf[i].param) {
+                       offset = pin * (pcs->width / BITS_PER_BYTE);
+                       data = pcs->read(pcs->base + offset);
+                       argument = pinconf_to_config_argument(config);
+                       switch (func->conf[i].param) {
+                       /* 2 parameters */
+                       case PIN_CONFIG_INPUT_SCHMITT:
+                       case PIN_CONFIG_DRIVE_STRENGTH:
+                       case PIN_CONFIG_SLEW_RATE:
+                               shift = ffs(func->conf[i].mask) - 1;
+                               arg = pinconf_to_config_argument(config);
+                               data &= ~func->conf[i].mask;
+                               data |= (arg << shift) & func->conf[i].mask;
+                               break;
+                       /* 4 parameters */
+                       case PIN_CONFIG_BIAS_DISABLE:
+                               pcs_pinconf_clear_bias(pctldev, pin);
+                               break;
+                       case PIN_CONFIG_BIAS_PULL_DOWN:
+                       case PIN_CONFIG_BIAS_PULL_UP:
+                               if (argument)
+                                       pcs_pinconf_clear_bias(pctldev, pin);
+                               /* fall through */
+                       case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
+                               data &= ~func->conf[i].mask;
+                               if (argument)
+                                       data |= func->conf[i].enable;
+                               else
+                                       data |= func->conf[i].disable;
+                               break;
+                       default:
+                               return -ENOTSUPP;
+                       }
+                       pcs->write(data, pcs->base + offset);
+                       return 0;
+               }
+       }
        return -ENOTSUPP;
 }
 
 static int pcs_pinconf_group_get(struct pinctrl_dev *pctldev,
                                unsigned group, unsigned long *config)
 {
-       return -ENOTSUPP;
+       const unsigned *pins;
+       unsigned npins, old = 0;
+       int i, ret;
+
+       ret = pcs_get_group_pins(pctldev, group, &pins, &npins);
+       if (ret)
+               return ret;
+       for (i = 0; i < npins; i++) {
+               if (pcs_pinconf_get(pctldev, pins[i], config))
+                       return -ENOTSUPP;
+               /* configs do not match between two pins */
+               if (i && (old != *config))
+                       return -ENOTSUPP;
+               old = *config;
+       }
+       return 0;
 }
 
 static int pcs_pinconf_group_set(struct pinctrl_dev *pctldev,
                                unsigned group, unsigned long config)
 {
-       return -ENOTSUPP;
+       const unsigned *pins;
+       unsigned npins;
+       int i, ret;
+
+       ret = pcs_get_group_pins(pctldev, group, &pins, &npins);
+       if (ret)
+               return ret;
+       for (i = 0; i < npins; i++) {
+               if (pcs_pinconf_set(pctldev, pins[i], config))
+                       return -ENOTSUPP;
+       }
+       return 0;
 }
 
 static void pcs_pinconf_dbg_show(struct pinctrl_dev *pctldev,
-                               struct seq_file *s, unsigned offset)
+                               struct seq_file *s, unsigned pin)
 {
 }
 
@@ -495,6 +719,13 @@ static void pcs_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
 {
 }
 
+static void pcs_pinconf_config_dbg_show(struct pinctrl_dev *pctldev,
+                                       struct seq_file *s,
+                                       unsigned long config)
+{
+       pinconf_generic_dump_config(pctldev, s, config);
+}
+
 static const struct pinconf_ops pcs_pinconf_ops = {
        .pin_config_get = pcs_pinconf_get,
        .pin_config_set = pcs_pinconf_set,
@@ -502,6 +733,7 @@ static const struct pinconf_ops pcs_pinconf_ops = {
        .pin_config_group_set = pcs_pinconf_group_set,
        .pin_config_dbg_show = pcs_pinconf_dbg_show,
        .pin_config_group_dbg_show = pcs_pinconf_group_dbg_show,
+       .pin_config_config_dbg_show = pcs_pinconf_config_dbg_show,
 };
 
 /**
@@ -692,11 +924,157 @@ static int pcs_get_pin_by_offset(struct pcs_device *pcs, unsigned offset)
        return index;
 }
 
+/*
+ * check whether data matches enable bits or disable bits
+ * Return value: 1 for matching enable bits, 0 for matching disable bits,
+ *               and negative value for matching failure.
+ */
+static int pcs_config_match(unsigned data, unsigned enable, unsigned disable)
+{
+       int ret = -EINVAL;
+
+       if (data == enable)
+               ret = 1;
+       else if (data == disable)
+               ret = 0;
+       return ret;
+}
+
+static void add_config(struct pcs_conf_vals **conf, enum pin_config_param param,
+                      unsigned value, unsigned enable, unsigned disable,
+                      unsigned mask)
+{
+       (*conf)->param = param;
+       (*conf)->val = value;
+       (*conf)->enable = enable;
+       (*conf)->disable = disable;
+       (*conf)->mask = mask;
+       (*conf)++;
+}
+
+static void add_setting(unsigned long **setting, enum pin_config_param param,
+                       unsigned arg)
+{
+       **setting = pinconf_to_config_packed(param, arg);
+       (*setting)++;
+}
+
+/* add pinconf setting with 2 parameters */
+static void pcs_add_conf2(struct pcs_device *pcs, struct device_node *np,
+                         const char *name, enum pin_config_param param,
+                         struct pcs_conf_vals **conf, unsigned long **settings)
+{
+       unsigned value[2];
+       int ret;
+
+       ret = of_property_read_u32_array(np, name, value, 2);
+       if (ret)
+               return;
+       /* set value & mask */
+       value[0] &= value[1];
+       /* skip enable & disable */
+       add_config(conf, param, value[0], 0, 0, value[1]);
+       add_setting(settings, param, value[0]);
+}
+
+/* add pinconf setting with 4 parameters */
+static void pcs_add_conf4(struct pcs_device *pcs, struct device_node *np,
+                         const char *name, enum pin_config_param param,
+                         struct pcs_conf_vals **conf, unsigned long **settings)
+{
+       unsigned value[4];
+       int ret;
+
+       /* value to set, enable, disable, mask */
+       ret = of_property_read_u32_array(np, name, value, 4);
+       if (ret)
+               return;
+       if (!value[3]) {
+               dev_err(pcs->dev, "mask field of the property can't be 0\n");
+               return;
+       }
+       value[0] &= value[3];
+       value[1] &= value[3];
+       value[2] &= value[3];
+       ret = pcs_config_match(value[0], value[1], value[2]);
+       if (ret < 0)
+               dev_dbg(pcs->dev, "failed to match enable or disable bits\n");
+       add_config(conf, param, value[0], value[1], value[2], value[3]);
+       add_setting(settings, param, ret);
+}
+
+static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np,
+                            struct pcs_function *func,
+                            struct pinctrl_map **map)
+
+{
+       struct pinctrl_map *m = *map;
+       int i = 0, nconfs = 0;
+       unsigned long *settings = NULL, *s = NULL;
+       struct pcs_conf_vals *conf = NULL;
+       struct pcs_conf_type prop2[] = {
+               { "pinctrl-single,drive-strength", PIN_CONFIG_DRIVE_STRENGTH, },
+               { "pinctrl-single,slew-rate", PIN_CONFIG_SLEW_RATE, },
+               { "pinctrl-single,input-schmitt", PIN_CONFIG_INPUT_SCHMITT, },
+       };
+       struct pcs_conf_type prop4[] = {
+               { "pinctrl-single,bias-pullup", PIN_CONFIG_BIAS_PULL_UP, },
+               { "pinctrl-single,bias-pulldown", PIN_CONFIG_BIAS_PULL_DOWN, },
+               { "pinctrl-single,input-schmitt-enable",
+                       PIN_CONFIG_INPUT_SCHMITT_ENABLE, },
+       };
+
+       /* If pinconf isn't supported, don't parse properties in below. */
+       if (!pcs->is_pinconf)
+               return 0;
+
+       /* cacluate how much properties are supported in current node */
+       for (i = 0; i < ARRAY_SIZE(prop2); i++) {
+               if (of_find_property(np, prop2[i].name, NULL))
+                       nconfs++;
+       }
+       for (i = 0; i < ARRAY_SIZE(prop4); i++) {
+               if (of_find_property(np, prop4[i].name, NULL))
+                       nconfs++;
+       }
+       if (!nconfs)
+               return 0;
+
+       func->conf = devm_kzalloc(pcs->dev,
+                                 sizeof(struct pcs_conf_vals) * nconfs,
+                                 GFP_KERNEL);
+       if (!func->conf)
+               return -ENOMEM;
+       func->nconfs = nconfs;
+       conf = &(func->conf[0]);
+       m++;
+       settings = devm_kzalloc(pcs->dev, sizeof(unsigned long) * nconfs,
+                               GFP_KERNEL);
+       if (!settings)
+               return -ENOMEM;
+       s = &settings[0];
+
+       for (i = 0; i < ARRAY_SIZE(prop2); i++)
+               pcs_add_conf2(pcs, np, prop2[i].name, prop2[i].param,
+                             &conf, &s);
+       for (i = 0; i < ARRAY_SIZE(prop4); i++)
+               pcs_add_conf4(pcs, np, prop4[i].name, prop4[i].param,
+                             &conf, &s);
+       m->type = PIN_MAP_TYPE_CONFIGS_GROUP;
+       m->data.configs.group_or_pin = np->name;
+       m->data.configs.configs = settings;
+       m->data.configs.num_configs = nconfs;
+       return 0;
+}
+
+static void pcs_free_pingroups(struct pcs_device *pcs);
+
 /**
  * smux_parse_one_pinctrl_entry() - parses a device tree mux entry
  * @pcs: pinctrl driver instance
  * @np: device node of the mux entry
  * @map: map entry
+ * @num_maps: number of map
  * @pgnames: pingroup names
  *
  * Note that this binding currently supports only sets of one register + value.
@@ -713,6 +1091,7 @@ static int pcs_get_pin_by_offset(struct pcs_device *pcs, unsigned offset)
 static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs,
                                                struct device_node *np,
                                                struct pinctrl_map **map,
+                                               unsigned *num_maps,
                                                const char **pgnames)
 {
        struct pcs_func_vals *vals;
@@ -785,8 +1164,18 @@ static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs,
        (*map)->data.mux.group = np->name;
        (*map)->data.mux.function = np->name;
 
+       if (pcs->is_pinconf) {
+               if (pcs_parse_pinconf(pcs, np, function, map))
+                       goto free_pingroups;
+               *num_maps = 2;
+       } else {
+               *num_maps = 1;
+       }
        return 0;
 
+free_pingroups:
+       pcs_free_pingroups(pcs);
+       *num_maps = 1;
 free_function:
        pcs_remove_function(pcs, function);
 
@@ -815,7 +1204,8 @@ static int pcs_dt_node_to_map(struct pinctrl_dev *pctldev,
 
        pcs = pinctrl_dev_get_drvdata(pctldev);
 
-       *map = devm_kzalloc(pcs->dev, sizeof(**map), GFP_KERNEL);
+       /* create 2 maps. One is for pinmux, and the other is for pinconf. */
+       *map = devm_kzalloc(pcs->dev, sizeof(**map) * 2, GFP_KERNEL);
        if (!*map)
                return -ENOMEM;
 
@@ -827,13 +1217,13 @@ static int pcs_dt_node_to_map(struct pinctrl_dev *pctldev,
                goto free_map;
        }
 
-       ret = pcs_parse_one_pinctrl_entry(pcs, np_config, map, pgnames);
+       ret = pcs_parse_one_pinctrl_entry(pcs, np_config, map, num_maps,
+                                         pgnames);
        if (ret < 0) {
                dev_err(pcs->dev, "no pins entries for %s\n",
                        np_config->name);
                goto free_pgnames;
        }
-       *num_maps = 1;
 
        return 0;
 
@@ -976,6 +1366,7 @@ static int pcs_probe(struct platform_device *pdev)
        INIT_LIST_HEAD(&pcs->pingroups);
        INIT_LIST_HEAD(&pcs->functions);
        INIT_LIST_HEAD(&pcs->gpiofuncs);
+       pcs->is_pinconf = match->data;
 
        PCS_GET_PROP_U32("pinctrl-single,register-width", &pcs->width,
                         "register width not specified\n");
@@ -1046,6 +1437,8 @@ static int pcs_probe(struct platform_device *pdev)
        pcs->desc.pmxops = &pcs_pinmux_ops;
        pcs->desc.confops = &pcs_pinconf_ops;
        pcs->desc.owner = THIS_MODULE;
+       if (match->data)
+               pcs_pinconf_ops.is_generic = true;
 
        ret = pcs_allocate_pin_table(pcs);
        if (ret < 0)
@@ -1086,7 +1479,8 @@ static int pcs_remove(struct platform_device *pdev)
 }
 
 static struct of_device_id pcs_of_match[] = {
-       { .compatible = DRIVER_NAME, },
+       { .compatible = "pinctrl-single", .data = (void *)false },
+       { .compatible = "pinconf-single", .data = (void *)true },
        { },
 };
 MODULE_DEVICE_TABLE(of, pcs_of_match);