drivers/pinctrl/meson/pinctrl-meson.c

   1 /*
   2  * (C) Copyright 2016 - Beniamino Galvani <b.galvani@gmail.com>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <dm.h>
   9 #include <dm/pinctrl.h>
  10 #include <fdt_support.h>
  11 #include <linux/err.h>
  12 #include <linux/io.h>
  13 #include <linux/sizes.h>
  14
  15 #include "pinctrl-meson.h"
  16
  17 DECLARE_GLOBAL_DATA_PTR;
  18
  19 static const char *meson_pinctrl_dummy_name = "_dummy";
  20
  21 static int meson_pinctrl_get_groups_count(struct udevice *dev)
  22 {
  23         struct meson_pinctrl *priv = dev_get_priv(dev);
  24
  25         return priv->data->num_groups;
  26 }
  27
  28 static const char *meson_pinctrl_get_group_name(struct udevice *dev,
  29                                                 unsigned selector)
  30 {
  31         struct meson_pinctrl *priv = dev_get_priv(dev);
  32
  33         if (!priv->data->groups[selector].name)
  34                 return meson_pinctrl_dummy_name;
  35
  36         return priv->data->groups[selector].name;
  37 }
  38
  39 static int meson_pinmux_get_functions_count(struct udevice *dev)
  40 {
  41         struct meson_pinctrl *priv = dev_get_priv(dev);
  42
  43         return priv->data->num_funcs;
  44 }
  45
  46 static const char *meson_pinmux_get_function_name(struct udevice *dev,
  47                                                   unsigned selector)
  48 {
  49         struct meson_pinctrl *priv = dev_get_priv(dev);
  50
  51         return priv->data->funcs[selector].name;
  52 }
  53
  54 static void meson_pinmux_disable_other_groups(struct meson_pinctrl *priv,
  55                                               unsigned int pin, int sel_group)
  56 {
  57         struct meson_pmx_group *group;
  58         void __iomem *addr;
  59         int i, j;
  60
  61         for (i = 0; i < priv->data->num_groups; i++) {
  62                 group = &priv->data->groups[i];
  63                 if (group->is_gpio || i == sel_group)
  64                         continue;
  65
  66                 for (j = 0; j < group->num_pins; j++) {
  67                         if (group->pins[j] == pin) {
  68                                 /* We have found a group using the pin */
  69                                 debug("pinmux: disabling %s\n", group->name);
  70                                 addr = priv->reg_mux + group->reg * 4;
  71                                 writel(readl(addr) & ~BIT(group->bit), addr);
  72                         }
  73                 }
  74         }
  75 }
  76
  77 static int meson_pinmux_group_set(struct udevice *dev,
  78                                   unsigned group_selector,
  79                                   unsigned func_selector)
  80 {
  81         struct meson_pinctrl *priv = dev_get_priv(dev);
  82         const struct meson_pmx_group *group;
  83         const struct meson_pmx_func *func;
  84         void __iomem *addr;
  85         int i;
  86
  87         group = &priv->data->groups[group_selector];
  88         func = &priv->data->funcs[func_selector];
  89
  90         debug("pinmux: set group %s func %s\n", group->name, func->name);
  91
  92         /*
  93          * Disable groups using the same pins.
  94          * The selected group is not disabled to avoid glitches.
  95          */
  96         for (i = 0; i < group->num_pins; i++) {
  97                 meson_pinmux_disable_other_groups(priv,
  98                                                   group->pins[i],
  99                                                   group_selector);
 100         }
 101
 102         /* Function 0 (GPIO) doesn't need any additional setting */
 103         if (func_selector) {
 104                 addr = priv->reg_mux + group->reg * 4;
 105                 writel(readl(addr) | BIT(group->bit), addr);
 106         }
 107
 108         return 0;
 109 }
 110
 111 const struct pinctrl_ops meson_pinctrl_ops = {
 112         .get_groups_count = meson_pinctrl_get_groups_count,
 113         .get_group_name = meson_pinctrl_get_group_name,
 114         .get_functions_count = meson_pinmux_get_functions_count,
 115         .get_function_name = meson_pinmux_get_function_name,
 116         .pinmux_group_set = meson_pinmux_group_set,
 117         .set_state = pinctrl_generic_set_state,
 118 };
 119
 120 static fdt_addr_t parse_address(int offset, const char *name, int na, int ns)
 121 {
 122         int index, len = 0;
 123         const fdt32_t *reg;
 124
 125         index = fdt_stringlist_search(gd->fdt_blob, offset, "reg-names", name);
 126         if (index < 0)
 127                 return FDT_ADDR_T_NONE;
 128
 129         reg = fdt_getprop(gd->fdt_blob, offset, "reg", &len);
 130         if (!reg || (len <= (index * sizeof(fdt32_t) * (na + ns))))
 131                 return FDT_ADDR_T_NONE;
 132
 133         reg += index * (na + ns);
 134
 135         return fdt_translate_address((void *)gd->fdt_blob, offset, reg);
 136 }
 137
 138 int meson_pinctrl_probe(struct udevice *dev)
 139 {
 140         struct meson_pinctrl *priv = dev_get_priv(dev);
 141         fdt_addr_t addr;
 142         int node, gpio = -1, len;
 143         int na, ns;
 144
 145         na = fdt_address_cells(gd->fdt_blob, dev_of_offset(dev->parent));
 146         if (na < 1) {
 147                 debug("bad #address-cells\n");
 148                 return -EINVAL;
 149         }
 150
 151         ns = fdt_size_cells(gd->fdt_blob, dev_of_offset(dev->parent));
 152         if (ns < 1) {
 153                 debug("bad #size-cells\n");
 154                 return -EINVAL;
 155         }
 156
 157         fdt_for_each_subnode(node, gd->fdt_blob, dev_of_offset(dev)) {
 158                 if (fdt_getprop(gd->fdt_blob, node, "gpio-controller", &len)) {
 159                         gpio = node;
 160                         break;
 161                 }
 162         }
 163
 164         if (!gpio) {
 165                 debug("gpio node not found\n");
 166                 return -EINVAL;
 167         }
 168
 169         addr = parse_address(gpio, "mux", na, ns);
 170         if (addr == FDT_ADDR_T_NONE) {
 171                 debug("mux not found\n");
 172                 return -EINVAL;
 173         }
 174
 175         priv->reg_mux = (void __iomem *)addr;
 176         priv->data = (struct meson_pinctrl_data *)dev_get_driver_data(dev);
 177
 178         return 0;
 179 }