drivers/pinctrl/pinctrl-single.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) EETS GmbH, 2017, Felix Brack <f.brack@eets.ch>
   4  */
   5
   6 #include <common.h>
   7 #include <dm.h>
   8 #include <dm/pinctrl.h>
   9 #include <linux/libfdt.h>
  10 #include <asm/io.h>
  11
  12 DECLARE_GLOBAL_DATA_PTR;
  13
  14 struct single_pdata {
  15         fdt_addr_t base;        /* first configuration register */
  16         int offset;             /* index of last configuration register */
  17         u32 mask;               /* configuration-value mask bits */
  18         int width;              /* configuration register bit width */
  19         bool bits_per_mux;
  20 };
  21
  22 struct single_fdt_pin_cfg {
  23         fdt32_t reg;            /* configuration register offset */
  24         fdt32_t val;            /* configuration register value */
  25 };
  26
  27 struct single_fdt_bits_cfg {
  28         fdt32_t reg;            /* configuration register offset */
  29         fdt32_t val;            /* configuration register value */
  30         fdt32_t mask;           /* configuration register mask */
  31 };
  32
  33 /**
  34  * single_configure_pins() - Configure pins based on FDT data
  35  *
  36  * @dev: Pointer to single pin configuration device which is the parent of
  37  *       the pins node holding the pin configuration data.
  38  * @pins: Pointer to the first element of an array of register/value pairs
  39  *        of type 'struct single_fdt_pin_cfg'. Each such pair describes the
  40  *        the pin to be configured and the value to be used for configuration.
  41  *        This pointer points to a 'pinctrl-single,pins' property in the
  42  *        device-tree.
  43  * @size: Size of the 'pins' array in bytes.
  44  *        The number of register/value pairs in the 'pins' array therefore
  45  *        equals to 'size / sizeof(struct single_fdt_pin_cfg)'.
  46  */
  47 static int single_configure_pins(struct udevice *dev,
  48                                  const struct single_fdt_pin_cfg *pins,
  49                                  int size)
  50 {
  51         struct single_pdata *pdata = dev->platdata;
  52         int count = size / sizeof(struct single_fdt_pin_cfg);
  53         phys_addr_t n, reg;
  54         u32 val;
  55
  56         for (n = 0; n < count; n++, pins++) {
  57                 reg = fdt32_to_cpu(pins->reg);
  58                 if ((reg < 0) || (reg > pdata->offset)) {
  59                         dev_dbg(dev, "  invalid register offset 0x%pa\n", &reg);
  60                         continue;
  61                 }
  62                 reg += pdata->base;
  63                 val = fdt32_to_cpu(pins->val) & pdata->mask;
  64                 switch (pdata->width) {
  65                 case 16:
  66                         writew((readw(reg) & ~pdata->mask) | val, reg);
  67                         break;
  68                 case 32:
  69                         writel((readl(reg) & ~pdata->mask) | val, reg);
  70                         break;
  71                 default:
  72                         dev_warn(dev, "unsupported register width %i\n",
  73                                  pdata->width);
  74                         continue;
  75                 }
  76                 dev_dbg(dev, "  reg/val 0x%pa/0x%08x\n", &reg, val);
  77         }
  78         return 0;
  79 }
  80
  81 static int single_configure_bits(struct udevice *dev,
  82                                  const struct single_fdt_bits_cfg *pins,
  83                                  int size)
  84 {
  85         struct single_pdata *pdata = dev->platdata;
  86         int count = size / sizeof(struct single_fdt_bits_cfg);
  87         phys_addr_t n, reg;
  88         u32 val, mask;
  89
  90         for (n = 0; n < count; n++, pins++) {
  91                 reg = fdt32_to_cpu(pins->reg);
  92                 if ((reg < 0) || (reg > pdata->offset)) {
  93                         dev_dbg(dev, "  invalid register offset 0x%pa\n", &reg);
  94                         continue;
  95                 }
  96                 reg += pdata->base;
  97
  98                 mask = fdt32_to_cpu(pins->mask);
  99                 val = fdt32_to_cpu(pins->val) & mask;
 100
 101                 switch (pdata->width) {
 102                 case 16:
 103                         writew((readw(reg) & ~mask) | val, reg);
 104                         break;
 105                 case 32:
 106                         writel((readl(reg) & ~mask) | val, reg);
 107                         break;
 108                 default:
 109                         dev_warn(dev, "unsupported register width %i\n",
 110                                  pdata->width);
 111                         continue;
 112                 }
 113                 dev_dbg(dev, "  reg/val 0x%pa/0x%08x\n", &reg, val);
 114         }
 115         return 0;
 116 }
 117 static int single_set_state(struct udevice *dev,
 118                             struct udevice *config)
 119 {
 120         const void *fdt = gd->fdt_blob;
 121         const struct single_fdt_pin_cfg *prop;
 122         const struct single_fdt_bits_cfg *prop_bits;
 123         int len;
 124
 125         prop = fdt_getprop(fdt, dev_of_offset(config), "pinctrl-single,pins",
 126                            &len);
 127
 128         if (prop) {
 129                 dev_dbg(dev, "configuring pins for %s\n", config->name);
 130                 if (len % sizeof(struct single_fdt_pin_cfg)) {
 131                         dev_dbg(dev, "  invalid pin configuration in fdt\n");
 132                         return -FDT_ERR_BADSTRUCTURE;
 133                 }
 134                 single_configure_pins(dev, prop, len);
 135                 return 0;
 136         }
 137
 138         /* pinctrl-single,pins not found so check for pinctrl-single,bits */
 139         prop_bits = fdt_getprop(fdt, dev_of_offset(config),
 140                                 "pinctrl-single,bits",
 141                                     &len);
 142         if (prop_bits) {
 143                 dev_dbg(dev, "configuring pins for %s\n", config->name);
 144                 if (len % sizeof(struct single_fdt_bits_cfg)) {
 145                         dev_dbg(dev, "  invalid bits configuration in fdt\n");
 146                         return -FDT_ERR_BADSTRUCTURE;
 147                 }
 148                 single_configure_bits(dev, prop_bits, len);
 149                 return 0;
 150         }
 151
 152         /* Neither 'pinctrl-single,pins' nor 'pinctrl-single,bits' were found */
 153         return len;
 154 }
 155
 156 static int single_ofdata_to_platdata(struct udevice *dev)
 157 {
 158         fdt_addr_t addr;
 159         u32 of_reg[2];
 160         int res;
 161         struct single_pdata *pdata = dev->platdata;
 162
 163         pdata->width = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
 164                                       "pinctrl-single,register-width", 0);
 165
 166         res = fdtdec_get_int_array(gd->fdt_blob, dev_of_offset(dev),
 167                                    "reg", of_reg, 2);
 168         if (res)
 169                 return res;
 170         pdata->offset = of_reg[1] - pdata->width / 8;
 171
 172         addr = devfdt_get_addr(dev);
 173         if (addr == FDT_ADDR_T_NONE) {
 174                 dev_dbg(dev, "no valid base register address\n");
 175                 return -EINVAL;
 176         }
 177         pdata->base = addr;
 178
 179         pdata->mask = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
 180                                      "pinctrl-single,function-mask",
 181                                      0xffffffff);
 182         pdata->bits_per_mux = fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
 183                                               "pinctrl-single,bit-per-mux");
 184
 185         return 0;
 186 }
 187
 188 const struct pinctrl_ops single_pinctrl_ops = {
 189         .set_state = single_set_state,
 190 };
 191
 192 static const struct udevice_id single_pinctrl_match[] = {
 193         { .compatible = "pinctrl-single" },
 194         { /* sentinel */ }
 195 };
 196
 197 U_BOOT_DRIVER(single_pinctrl) = {
 198         .name = "single-pinctrl",
 199         .id = UCLASS_PINCTRL,
 200         .of_match = single_pinctrl_match,
 201         .ops = &single_pinctrl_ops,
 202         .platdata_auto_alloc_size = sizeof(struct single_pdata),
 203         .ofdata_to_platdata = single_ofdata_to_platdata,
 204 };