mfd: AXP20x: Add mfd driver for AXP20x PMIC

This patch introduces the preliminary support for PMICs X-Powers AXP202
and AXP209. The AXP209 and AXP202 are the PMUs (Power Management Unit)
used by A10, A13 and A20 SoCs and developed by X-Powers, a sister company
of Allwinner.

The core enables support for two subsystems:
- PEK (Power Enable Key)
- Regulators

Signed-off-by: Carlo Caione <carlo@caione.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 258 insertions, 0 deletions

diff --git a/drivers/mfd/axp20x.c b/drivers/mfd/axp20x.c
new file mode 100644
index 000000000000..dee653989e3a
--- /dev/null
+++ b/drivers/mfd/axp20x.c
@@ -0,0 +1,258 @@
+/*
+ * axp20x.c - MFD core driver for the X-Powers AXP202 and AXP209
+ *
+ * AXP20x comprises an adaptive USB-Compatible PWM charger, 2 BUCK DC-DC
+ * converters, 5 LDOs, multiple 12-bit ADCs of voltage, current and temperature
+ * as well as 4 configurable GPIOs.
+ *
+ * Author: Carlo Caione <carlo@caione.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+#include <linux/mfd/axp20x.h>
+#include <linux/mfd/core.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+
+#define AXP20X_OFF      0x80
+
+static const struct regmap_range axp20x_writeable_ranges[] = {
+        regmap_reg_range(AXP20X_DATACACHE(0), AXP20X_IRQ5_STATE),
+        regmap_reg_range(AXP20X_DCDC_MODE, AXP20X_FG_RES),
+};
+
+static const struct regmap_range axp20x_volatile_ranges[] = {
+        regmap_reg_range(AXP20X_IRQ1_EN, AXP20X_IRQ5_STATE),
+};
+
+static const struct regmap_access_table axp20x_writeable_table = {
+        .yes_ranges     = axp20x_writeable_ranges,
+        .n_yes_ranges   = ARRAY_SIZE(axp20x_writeable_ranges),
+};
+
+static const struct regmap_access_table axp20x_volatile_table = {
+        .yes_ranges     = axp20x_volatile_ranges,
+        .n_yes_ranges   = ARRAY_SIZE(axp20x_volatile_ranges),
+};
+
+static struct resource axp20x_pek_resources[] = {
+        {
+                .name   = "PEK_DBR",
+                .start  = AXP20X_IRQ_PEK_RIS_EDGE,
+                .end    = AXP20X_IRQ_PEK_RIS_EDGE,
+                .flags  = IORESOURCE_IRQ,
+        }, {
+                .name   = "PEK_DBF",
+                .start  = AXP20X_IRQ_PEK_FAL_EDGE,
+                .end    = AXP20X_IRQ_PEK_FAL_EDGE,
+                .flags  = IORESOURCE_IRQ,
+        },
+};
+
+static const struct regmap_config axp20x_regmap_config = {
+        .reg_bits       = 8,
+        .val_bits       = 8,
+        .wr_table       = &axp20x_writeable_table,
+        .volatile_table = &axp20x_volatile_table,
+        .max_register   = AXP20X_FG_RES,
+        .cache_type     = REGCACHE_RBTREE,
+};
+
+#define AXP20X_IRQ(_irq, _off, _mask) \
+        [AXP20X_IRQ_##_irq] = { .reg_offset = (_off), .mask = BIT(_mask) }
+
+static const struct regmap_irq axp20x_regmap_irqs[] = {
+        AXP20X_IRQ(ACIN_OVER_V,         0, 7),
+        AXP20X_IRQ(ACIN_PLUGIN,         0, 6),
+        AXP20X_IRQ(ACIN_REMOVAL,        0, 5),
+        AXP20X_IRQ(VBUS_OVER_V,         0, 4),
+        AXP20X_IRQ(VBUS_PLUGIN,         0, 3),
+        AXP20X_IRQ(VBUS_REMOVAL,        0, 2),
+        AXP20X_IRQ(VBUS_V_LOW,          0, 1),
+        AXP20X_IRQ(BATT_PLUGIN,         1, 7),
+        AXP20X_IRQ(BATT_REMOVAL,        1, 6),
+        AXP20X_IRQ(BATT_ENT_ACT_MODE,   1, 5),
+        AXP20X_IRQ(BATT_EXIT_ACT_MODE,  1, 4),
+        AXP20X_IRQ(CHARG,               1, 3),
+        AXP20X_IRQ(CHARG_DONE,          1, 2),
+        AXP20X_IRQ(BATT_TEMP_HIGH,      1, 1),
+        AXP20X_IRQ(BATT_TEMP_LOW,       1, 0),
+        AXP20X_IRQ(DIE_TEMP_HIGH,       2, 7),
+        AXP20X_IRQ(CHARG_I_LOW,         2, 6),
+        AXP20X_IRQ(DCDC1_V_LONG,        2, 5),
+        AXP20X_IRQ(DCDC2_V_LONG,        2, 4),
+        AXP20X_IRQ(DCDC3_V_LONG,        2, 3),
+        AXP20X_IRQ(PEK_SHORT,           2, 1),
+        AXP20X_IRQ(PEK_LONG,            2, 0),
+        AXP20X_IRQ(N_OE_PWR_ON,         3, 7),
+        AXP20X_IRQ(N_OE_PWR_OFF,        3, 6),
+        AXP20X_IRQ(VBUS_VALID,          3, 5),
+        AXP20X_IRQ(VBUS_NOT_VALID,      3, 4),
+        AXP20X_IRQ(VBUS_SESS_VALID,     3, 3),
+        AXP20X_IRQ(VBUS_SESS_END,       3, 2),
+        AXP20X_IRQ(LOW_PWR_LVL1,        3, 1),
+        AXP20X_IRQ(LOW_PWR_LVL2,        3, 0),
+        AXP20X_IRQ(TIMER,               4, 7),
+        AXP20X_IRQ(PEK_RIS_EDGE,        4, 6),
+        AXP20X_IRQ(PEK_FAL_EDGE,        4, 5),
+        AXP20X_IRQ(GPIO3_INPUT,         4, 3),
+        AXP20X_IRQ(GPIO2_INPUT,         4, 2),
+        AXP20X_IRQ(GPIO1_INPUT,         4, 1),
+        AXP20X_IRQ(GPIO0_INPUT,         4, 0),
+};
+
+static const struct of_device_id axp20x_of_match[] = {
+        { .compatible = "x-powers,axp202", .data = (void *) AXP202_ID },
+        { .compatible = "x-powers,axp209", .data = (void *) AXP209_ID },
+        { },
+};
+MODULE_DEVICE_TABLE(of, axp20x_of_match);
+
+/*
+ * This is useless for OF-enabled devices, but it is needed by I2C subsystem
+ */
+static const struct i2c_device_id axp20x_i2c_id[] = {
+        { },
+};
+MODULE_DEVICE_TABLE(i2c, axp20x_i2c_id);
+
+static const struct regmap_irq_chip axp20x_regmap_irq_chip = {
+        .name                   = "axp20x_irq_chip",
+        .status_base            = AXP20X_IRQ1_STATE,
+        .ack_base               = AXP20X_IRQ1_STATE,
+        .mask_base              = AXP20X_IRQ1_EN,
+        .num_regs               = 5,
+        .irqs                   = axp20x_regmap_irqs,
+        .num_irqs               = ARRAY_SIZE(axp20x_regmap_irqs),
+        .mask_invert            = true,
+        .init_ack_masked        = true,
+};
+
+static const char * const axp20x_supplies[] = {
+        "acin",
+        "vin2",
+        "vin3",
+        "ldo24in",
+        "ldo3in",
+        "ldo5in",
+};
+
+static struct mfd_cell axp20x_cells[] = {
+        {
+                .name                   = "axp20x-pek",
+                .num_resources          = ARRAY_SIZE(axp20x_pek_resources),
+                .resources              = axp20x_pek_resources,
+        }, {
+                .name                   = "axp20x-regulator",
+                .parent_supplies        = axp20x_supplies,
+                .num_parent_supplies    = ARRAY_SIZE(axp20x_supplies),
+        },
+};
+
+static struct axp20x_dev *axp20x_pm_power_off;
+static void axp20x_power_off(void)
+{
+        regmap_write(axp20x_pm_power_off->regmap, AXP20X_OFF_CTRL,
+                     AXP20X_OFF);
+}
+
+static int axp20x_i2c_probe(struct i2c_client *i2c,
+                         const struct i2c_device_id *id)
+{
+        struct axp20x_dev *axp20x;
+        const struct of_device_id *of_id;
+        int ret;
+
+        axp20x = devm_kzalloc(&i2c->dev, sizeof(*axp20x), GFP_KERNEL);
+        if (!axp20x)
+                return -ENOMEM;
+
+        of_id = of_match_device(axp20x_of_match, &i2c->dev);
+        if (!of_id) {
+                dev_err(&i2c->dev, "Unable to setup AXP20X data\n");
+                return -ENODEV;
+        }
+        axp20x->variant = (long) of_id->data;
+
+        axp20x->i2c_client = i2c;
+        axp20x->dev = &i2c->dev;
+        dev_set_drvdata(axp20x->dev, axp20x);
+
+        axp20x->regmap = devm_regmap_init_i2c(i2c, &axp20x_regmap_config);
+        if (IS_ERR(axp20x->regmap)) {
+                ret = PTR_ERR(axp20x->regmap);
+                dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
+                return ret;
+        }
+
+        ret = regmap_add_irq_chip(axp20x->regmap, i2c->irq,
+                                  IRQF_ONESHOT | IRQF_SHARED, -1,
+                                  &axp20x_regmap_irq_chip,
+                                  &axp20x->regmap_irqc);
+        if (ret) {
+                dev_err(&i2c->dev, "failed to add irq chip: %d\n", ret);
+                return ret;
+        }
+
+        ret = mfd_add_devices(axp20x->dev, -1, axp20x_cells,
+                              ARRAY_SIZE(axp20x_cells), NULL, 0, NULL);
+
+        if (ret) {
+                dev_err(&i2c->dev, "failed to add MFD devices: %d\n", ret);
+                regmap_del_irq_chip(i2c->irq, axp20x->regmap_irqc);
+                return ret;
+        }
+
+        if (!pm_power_off) {
+                axp20x_pm_power_off = axp20x;
+                pm_power_off = axp20x_power_off;
+        }
+
+        dev_info(&i2c->dev, "AXP20X driver loaded\n");
+
+        return 0;
+}
+
+static int axp20x_i2c_remove(struct i2c_client *i2c)
+{
+        struct axp20x_dev *axp20x = i2c_get_clientdata(i2c);
+
+        if (axp20x == axp20x_pm_power_off) {
+                axp20x_pm_power_off = NULL;
+                pm_power_off = NULL;
+        }
+
+        mfd_remove_devices(axp20x->dev);
+        regmap_del_irq_chip(axp20x->i2c_client->irq, axp20x->regmap_irqc);
+
+        return 0;
+}
+
+static struct i2c_driver axp20x_i2c_driver = {
+        .driver = {
+                .name   = "axp20x",
+                .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(axp20x_of_match),
+        },
+        .probe          = axp20x_i2c_probe,
+        .remove         = axp20x_i2c_remove,
+        .id_table       = axp20x_i2c_id,
+};
+
+module_i2c_driver(axp20x_i2c_driver);
+
+MODULE_DESCRIPTION("PMIC MFD core driver for AXP20X");
+MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
+MODULE_LICENSE("GPL");