drivers/base/regmap/regmap-mdio.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <linux/errno.h>
   4 #include <linux/mdio.h>
   5 #include <linux/module.h>
   6 #include <linux/regmap.h>
   7
   8 #define REGVAL_MASK             GENMASK(15, 0)
   9 #define REGNUM_C22_MASK         GENMASK(4, 0)
  10 /* Clause-45 mask includes the device type (5 bit) and actual register number (16 bit) */
  11 #define REGNUM_C45_MASK         GENMASK(20, 0)
  12
  13 static int regmap_mdio_c22_read(void *context, unsigned int reg, unsigned int *val)
  14 {
  15         struct mdio_device *mdio_dev = context;
  16         int ret;
  17
  18         if (unlikely(reg & ~REGNUM_C22_MASK))
  19                 return -ENXIO;
  20
  21         ret = mdiodev_read(mdio_dev, reg);
  22         if (ret < 0)
  23                 return ret;
  24
  25         *val = ret & REGVAL_MASK;
  26
  27         return 0;
  28 }
  29
  30 static int regmap_mdio_c22_write(void *context, unsigned int reg, unsigned int val)
  31 {
  32         struct mdio_device *mdio_dev = context;
  33
  34         if (unlikely(reg & ~REGNUM_C22_MASK))
  35                 return -ENXIO;
  36
  37         return mdiodev_write(mdio_dev, reg, val);
  38 }
  39
  40 static const struct regmap_bus regmap_mdio_c22_bus = {
  41         .reg_write = regmap_mdio_c22_write,
  42         .reg_read = regmap_mdio_c22_read,
  43 };
  44
  45 static int regmap_mdio_c45_read(void *context, unsigned int reg, unsigned int *val)
  46 {
  47         struct mdio_device *mdio_dev = context;
  48         unsigned int devad;
  49         int ret;
  50
  51         if (unlikely(reg & ~REGNUM_C45_MASK))
  52                 return -ENXIO;
  53
  54         devad = reg >> REGMAP_MDIO_C45_DEVAD_SHIFT;
  55         reg = reg & REGMAP_MDIO_C45_REGNUM_MASK;
  56
  57         ret = mdiodev_c45_read(mdio_dev, devad, reg);
  58         if (ret < 0)
  59                 return ret;
  60
  61         *val = ret & REGVAL_MASK;
  62
  63         return 0;
  64 }
  65
  66 static int regmap_mdio_c45_write(void *context, unsigned int reg, unsigned int val)
  67 {
  68         struct mdio_device *mdio_dev = context;
  69         unsigned int devad;
  70
  71         if (unlikely(reg & ~REGNUM_C45_MASK))
  72                 return -ENXIO;
  73
  74         devad = reg >> REGMAP_MDIO_C45_DEVAD_SHIFT;
  75         reg = reg & REGMAP_MDIO_C45_REGNUM_MASK;
  76
  77         return mdiodev_c45_write(mdio_dev, devad, reg, val);
  78 }
  79
  80 static const struct regmap_bus regmap_mdio_c45_bus = {
  81         .reg_write = regmap_mdio_c45_write,
  82         .reg_read = regmap_mdio_c45_read,
  83 };
  84
  85 struct regmap *__regmap_init_mdio(struct mdio_device *mdio_dev,
  86         const struct regmap_config *config, struct lock_class_key *lock_key,
  87         const char *lock_name)
  88 {
  89         const struct regmap_bus *bus;
  90
  91         if (config->reg_bits == 5 && config->val_bits == 16)
  92                 bus = &regmap_mdio_c22_bus;
  93         else if (config->reg_bits == 21 && config->val_bits == 16)
  94                 bus = &regmap_mdio_c45_bus;
  95         else
  96                 return ERR_PTR(-EOPNOTSUPP);
  97
  98         return __regmap_init(&mdio_dev->dev, bus, mdio_dev, config, lock_key, lock_name);
  99 }
 100 EXPORT_SYMBOL_GPL(__regmap_init_mdio);
 101
 102 struct regmap *__devm_regmap_init_mdio(struct mdio_device *mdio_dev,
 103         const struct regmap_config *config, struct lock_class_key *lock_key,
 104         const char *lock_name)
 105 {
 106         const struct regmap_bus *bus;
 107
 108         if (config->reg_bits == 5 && config->val_bits == 16)
 109                 bus = &regmap_mdio_c22_bus;
 110         else if (config->reg_bits == 21 && config->val_bits == 16)
 111                 bus = &regmap_mdio_c45_bus;
 112         else
 113                 return ERR_PTR(-EOPNOTSUPP);
 114
 115         return __devm_regmap_init(&mdio_dev->dev, bus, mdio_dev, config, lock_key, lock_name);
 116 }
 117 EXPORT_SYMBOL_GPL(__devm_regmap_init_mdio);
 118
 119 MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
 120 MODULE_DESCRIPTION("regmap MDIO Module");
 121 MODULE_LICENSE("GPL v2");