drivers/mfd/rohm-bd9576.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2021 ROHM Semiconductors
   4  *
   5  * ROHM BD9576MUF and BD9573MUF PMIC driver
   6  */
   7
   8 #include <linux/i2c.h>
   9 #include <linux/interrupt.h>
  10 #include <linux/ioport.h>
  11 #include <linux/irq.h>
  12 #include <linux/mfd/core.h>
  13 #include <linux/mfd/rohm-bd957x.h>
  14 #include <linux/mfd/rohm-generic.h>
  15 #include <linux/module.h>
  16 #include <linux/of.h>
  17 #include <linux/regmap.h>
  18 #include <linux/types.h>
  19
  20 enum {
  21         BD957X_REGULATOR_CELL,
  22         BD957X_WDT_CELL,
  23 };
  24
  25 /*
  26  * Due to the BD9576MUF nasty IRQ behaviour we don't always populate IRQs.
  27  * These will be added to regulator resources only if IRQ information for the
  28  * PMIC is populated in device-tree.
  29  */
  30 static const struct resource bd9576_regulator_irqs[] = {
  31         DEFINE_RES_IRQ_NAMED(BD9576_INT_THERM, "bd9576-temp"),
  32         DEFINE_RES_IRQ_NAMED(BD9576_INT_OVD, "bd9576-ovd"),
  33         DEFINE_RES_IRQ_NAMED(BD9576_INT_UVD, "bd9576-uvd"),
  34 };
  35
  36 static struct mfd_cell bd9573_mfd_cells[] = {
  37         [BD957X_REGULATOR_CELL] = { .name = "bd9573-regulator", },
  38         [BD957X_WDT_CELL]       = { .name = "bd9576-wdt", },
  39 };
  40
  41 static struct mfd_cell bd9576_mfd_cells[] = {
  42         [BD957X_REGULATOR_CELL] = { .name = "bd9576-regulator", },
  43         [BD957X_WDT_CELL]       = { .name = "bd9576-wdt", },
  44 };
  45
  46 static const struct regmap_range volatile_ranges[] = {
  47         regmap_reg_range(BD957X_REG_SMRB_ASSERT, BD957X_REG_SMRB_ASSERT),
  48         regmap_reg_range(BD957X_REG_PMIC_INTERNAL_STAT,
  49                          BD957X_REG_PMIC_INTERNAL_STAT),
  50         regmap_reg_range(BD957X_REG_INT_THERM_STAT, BD957X_REG_INT_THERM_STAT),
  51         regmap_reg_range(BD957X_REG_INT_OVP_STAT, BD957X_REG_INT_SYS_STAT),
  52         regmap_reg_range(BD957X_REG_INT_MAIN_STAT, BD957X_REG_INT_MAIN_STAT),
  53 };
  54
  55 static const struct regmap_access_table volatile_regs = {
  56         .yes_ranges = &volatile_ranges[0],
  57         .n_yes_ranges = ARRAY_SIZE(volatile_ranges),
  58 };
  59
  60 static struct regmap_config bd957x_regmap = {
  61         .reg_bits = 8,
  62         .val_bits = 8,
  63         .volatile_table = &volatile_regs,
  64         .max_register = BD957X_MAX_REGISTER,
  65         .cache_type = REGCACHE_MAPLE,
  66 };
  67
  68 static struct regmap_irq bd9576_irqs[] = {
  69         REGMAP_IRQ_REG(BD9576_INT_THERM, 0, BD957X_MASK_INT_MAIN_THERM),
  70         REGMAP_IRQ_REG(BD9576_INT_OVP, 0, BD957X_MASK_INT_MAIN_OVP),
  71         REGMAP_IRQ_REG(BD9576_INT_SCP, 0, BD957X_MASK_INT_MAIN_SCP),
  72         REGMAP_IRQ_REG(BD9576_INT_OCP, 0, BD957X_MASK_INT_MAIN_OCP),
  73         REGMAP_IRQ_REG(BD9576_INT_OVD, 0, BD957X_MASK_INT_MAIN_OVD),
  74         REGMAP_IRQ_REG(BD9576_INT_UVD, 0, BD957X_MASK_INT_MAIN_UVD),
  75         REGMAP_IRQ_REG(BD9576_INT_UVP, 0, BD957X_MASK_INT_MAIN_UVP),
  76         REGMAP_IRQ_REG(BD9576_INT_SYS, 0, BD957X_MASK_INT_MAIN_SYS),
  77 };
  78
  79 static struct regmap_irq_chip bd9576_irq_chip = {
  80         .name = "bd9576_irq",
  81         .irqs = &bd9576_irqs[0],
  82         .num_irqs = ARRAY_SIZE(bd9576_irqs),
  83         .status_base = BD957X_REG_INT_MAIN_STAT,
  84         .mask_base = BD957X_REG_INT_MAIN_MASK,
  85         .ack_base = BD957X_REG_INT_MAIN_STAT,
  86         .init_ack_masked = true,
  87         .num_regs = 1,
  88         .irq_reg_stride = 1,
  89 };
  90
  91 static int bd957x_i2c_probe(struct i2c_client *i2c)
  92 {
  93         int ret;
  94         struct regmap *regmap;
  95         struct mfd_cell *cells;
  96         int num_cells;
  97         unsigned long chip_type;
  98         struct irq_domain *domain;
  99         bool usable_irqs;
 100
 101         chip_type = (unsigned long)of_device_get_match_data(&i2c->dev);
 102
 103         switch (chip_type) {
 104         case ROHM_CHIP_TYPE_BD9576:
 105                 cells = bd9576_mfd_cells;
 106                 num_cells = ARRAY_SIZE(bd9576_mfd_cells);
 107                 usable_irqs = !!i2c->irq;
 108                 break;
 109         case ROHM_CHIP_TYPE_BD9573:
 110                 cells = bd9573_mfd_cells;
 111                 num_cells = ARRAY_SIZE(bd9573_mfd_cells);
 112                 /*
 113                  * BD9573 only supports fatal IRQs which we can not handle
 114                  * because SoC is going to lose the power.
 115                  */
 116                 usable_irqs = false;
 117                 break;
 118         default:
 119                 dev_err(&i2c->dev, "Unknown device type");
 120                 return -EINVAL;
 121         }
 122
 123         regmap = devm_regmap_init_i2c(i2c, &bd957x_regmap);
 124         if (IS_ERR(regmap))
 125                 return dev_err_probe(&i2c->dev, PTR_ERR(regmap),
 126                                      "Failed to initialize Regmap\n");
 127
 128         /*
 129          * BD9576 behaves badly. It kepts IRQ line asserted for the whole
 130          * duration of detected HW condition (like over temperature). So we
 131          * don't require IRQ to be populated.
 132          * If IRQ information is not given, then we mask all IRQs and do not
 133          * provide IRQ resources to regulator driver - which then just omits
 134          * the notifiers.
 135          */
 136         if (usable_irqs) {
 137                 struct regmap_irq_chip_data *irq_data;
 138                 struct mfd_cell *regulators;
 139
 140                 regulators = &bd9576_mfd_cells[BD957X_REGULATOR_CELL];
 141                 regulators->resources = bd9576_regulator_irqs;
 142                 regulators->num_resources = ARRAY_SIZE(bd9576_regulator_irqs);
 143
 144                 ret = devm_regmap_add_irq_chip(&i2c->dev, regmap, i2c->irq,
 145                                                IRQF_ONESHOT, 0,
 146                                                &bd9576_irq_chip, &irq_data);
 147                 if (ret)
 148                         return dev_err_probe(&i2c->dev, ret,
 149                                              "Failed to add IRQ chip\n");
 150
 151                 domain = regmap_irq_get_domain(irq_data);
 152         } else {
 153                 ret = regmap_update_bits(regmap, BD957X_REG_INT_MAIN_MASK,
 154                                          BD957X_MASK_INT_ALL,
 155                                          BD957X_MASK_INT_ALL);
 156                 if (ret)
 157                         return ret;
 158                 domain = NULL;
 159         }
 160
 161         ret = devm_mfd_add_devices(&i2c->dev, PLATFORM_DEVID_AUTO, cells,
 162                                    num_cells, NULL, 0, domain);
 163         if (ret)
 164                 dev_err_probe(&i2c->dev, ret, "Failed to create subdevices\n");
 165
 166         return ret;
 167 }
 168
 169 static const struct of_device_id bd957x_of_match[] = {
 170         { .compatible = "rohm,bd9576", .data = (void *)ROHM_CHIP_TYPE_BD9576, },
 171         { .compatible = "rohm,bd9573", .data = (void *)ROHM_CHIP_TYPE_BD9573, },
 172         { },
 173 };
 174 MODULE_DEVICE_TABLE(of, bd957x_of_match);
 175
 176 static struct i2c_driver bd957x_drv = {
 177         .driver = {
 178                 .name = "rohm-bd957x",
 179                 .of_match_table = bd957x_of_match,
 180         },
 181         .probe = bd957x_i2c_probe,
 182 };
 183 module_i2c_driver(bd957x_drv);
 184
 185 MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
 186 MODULE_DESCRIPTION("ROHM BD9576MUF and BD9573MUF Power Management IC driver");
 187 MODULE_LICENSE("GPL");