root/drivers/mfd/motorola-cpcap.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Motorola CPCAP PMIC core driver
 *
 * Copyright (C) 2016 Tony Lindgren <tony@atomide.com>
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/regmap.h>
#include <linux/sysfs.h>

#include <linux/mfd/core.h>
#include <linux/mfd/motorola-cpcap.h>
#include <linux/spi/spi.h>

#define CPCAP_NR_IRQ_REG_BANKS  6
#define CPCAP_NR_IRQ_CHIPS      3
#define CPCAP_REGISTER_SIZE     4
#define CPCAP_REGISTER_BITS     16

struct cpcap_ddata {
        struct spi_device *spi;
        struct regmap_irq *irqs;
        struct regmap_irq_chip_data *irqdata[CPCAP_NR_IRQ_CHIPS];
        const struct regmap_config *regmap_conf;
        struct regmap *regmap;
};

static int cpcap_sense_irq(struct regmap *regmap, int irq)
{
        int regnum = irq / CPCAP_REGISTER_BITS;
        int mask = BIT(irq % CPCAP_REGISTER_BITS);
        int reg = CPCAP_REG_INTS1 + (regnum * CPCAP_REGISTER_SIZE);
        int err, val;

        if (reg < CPCAP_REG_INTS1 || reg > CPCAP_REG_INTS4)
                return -EINVAL;

        err = regmap_read(regmap, reg, &val);
        if (err)
                return err;

        return !!(val & mask);
}

int cpcap_sense_virq(struct regmap *regmap, int virq)
{
        struct regmap_irq_chip_data *d = irq_get_chip_data(virq);
        int irq_base = regmap_irq_chip_get_base(d);

        return cpcap_sense_irq(regmap, virq - irq_base);
}
EXPORT_SYMBOL_GPL(cpcap_sense_virq);

static int cpcap_check_revision(struct cpcap_ddata *cpcap)
{
        u16 vendor, rev;
        int ret;

        ret = cpcap_get_vendor(&cpcap->spi->dev, cpcap->regmap, &vendor);
        if (ret)
                return ret;

        ret = cpcap_get_revision(&cpcap->spi->dev, cpcap->regmap, &rev);
        if (ret)
                return ret;

        dev_info(&cpcap->spi->dev, "CPCAP vendor: %s rev: %i.%i (%x)\n",
                 vendor == CPCAP_VENDOR_ST ? "ST" : "TI",
                 CPCAP_REVISION_MAJOR(rev), CPCAP_REVISION_MINOR(rev),
                 rev);

        if (rev < CPCAP_REVISION_2_1) {
                dev_info(&cpcap->spi->dev,
                         "Please add old CPCAP revision support as needed\n");
                return -ENODEV;
        }

        return 0;
}

/*
 * First two irq chips are the two private macro interrupt chips, the third
 * irq chip is for register banks 1 - 4 and is available for drivers to use.
 */
static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = {
        {
                .name = "cpcap-m2",
                .num_regs = 1,
                .status_base = CPCAP_REG_MI1,
                .ack_base = CPCAP_REG_MI1,
                .mask_base = CPCAP_REG_MIM1,
                .use_ack = true,
                .clear_ack = true,
        },
        {
                .name = "cpcap-m2",
                .num_regs = 1,
                .status_base = CPCAP_REG_MI2,
                .ack_base = CPCAP_REG_MI2,
                .mask_base = CPCAP_REG_MIM2,
                .use_ack = true,
                .clear_ack = true,
        },
        {
                .name = "cpcap1-4",
                .num_regs = 4,
                .status_base = CPCAP_REG_INT1,
                .ack_base = CPCAP_REG_INT1,
                .mask_base = CPCAP_REG_INTM1,
                .use_ack = true,
                .clear_ack = true,
        },
};

static void cpcap_init_one_regmap_irq(struct cpcap_ddata *cpcap,
                                      struct regmap_irq *rirq,
                                      int irq_base, int irq)
{
        unsigned int reg_offset;
        unsigned int bit, mask;

        reg_offset = irq - irq_base;
        reg_offset /= cpcap->regmap_conf->val_bits;
        reg_offset *= cpcap->regmap_conf->reg_stride;

        bit = irq % cpcap->regmap_conf->val_bits;
        mask = (1 << bit);

        rirq->reg_offset = reg_offset;
        rirq->mask = mask;
}

static int cpcap_init_irq_chip(struct cpcap_ddata *cpcap, int irq_chip,
                               int irq_start, int nr_irqs)
{
        struct regmap_irq_chip *chip = &cpcap_irq_chip[irq_chip];
        int i, ret;

        for (i = irq_start; i < irq_start + nr_irqs; i++) {
                struct regmap_irq *rirq = &cpcap->irqs[i];

                cpcap_init_one_regmap_irq(cpcap, rirq, irq_start, i);
        }
        chip->irqs = &cpcap->irqs[irq_start];
        chip->num_irqs = nr_irqs;
        chip->irq_drv_data = cpcap;

        ret = devm_regmap_add_irq_chip(&cpcap->spi->dev, cpcap->regmap,
                                       cpcap->spi->irq,
                                       irq_get_trigger_type(cpcap->spi->irq) |
                                       IRQF_SHARED, -1,
                                       chip, &cpcap->irqdata[irq_chip]);
        if (ret) {
                dev_err(&cpcap->spi->dev, "could not add irq chip %i: %i\n",
                        irq_chip, ret);
                return ret;
        }

        return 0;
}

static int cpcap_init_irq(struct cpcap_ddata *cpcap)
{
        int ret;

        cpcap->irqs = devm_kzalloc(&cpcap->spi->dev,
                                   array3_size(sizeof(*cpcap->irqs),
                                               CPCAP_NR_IRQ_REG_BANKS,
                                               cpcap->regmap_conf->val_bits),
                                   GFP_KERNEL);
        if (!cpcap->irqs)
                return -ENOMEM;

        ret = cpcap_init_irq_chip(cpcap, 0, 0, 16);
        if (ret)
                return ret;

        ret = cpcap_init_irq_chip(cpcap, 1, 16, 16);
        if (ret)
                return ret;

        ret = cpcap_init_irq_chip(cpcap, 2, 32, 64);
        if (ret)
                return ret;

        enable_irq_wake(cpcap->spi->irq);

        return 0;
}

static const struct of_device_id cpcap_of_match[] = {
        { .compatible = "motorola,cpcap", },
        { .compatible = "st,6556002", },
        {},
};
MODULE_DEVICE_TABLE(of, cpcap_of_match);

static const struct spi_device_id cpcap_spi_ids[] = {
        { .name = "cpcap", },
        { .name = "6556002", },
        {},
};
MODULE_DEVICE_TABLE(spi, cpcap_spi_ids);

static const struct regmap_config cpcap_regmap_config = {
        .reg_bits = 16,
        .reg_stride = 4,
        .pad_bits = 0,
        .val_bits = 16,
        .write_flag_mask = 0x8000,
        .max_register = CPCAP_REG_ST_TEST2,
        .cache_type = REGCACHE_NONE,
        .reg_format_endian = REGMAP_ENDIAN_LITTLE,
        .val_format_endian = REGMAP_ENDIAN_LITTLE,
};

static int cpcap_suspend(struct device *dev)
{
        struct spi_device *spi = to_spi_device(dev);

        disable_irq(spi->irq);

        return 0;
}

static int cpcap_resume(struct device *dev)
{
        struct spi_device *spi = to_spi_device(dev);

        enable_irq(spi->irq);

        return 0;
}

static DEFINE_SIMPLE_DEV_PM_OPS(cpcap_pm, cpcap_suspend, cpcap_resume);

static const struct mfd_cell cpcap_mfd_devices[] = {
        {
                .name          = "cpcap_adc",
                .of_compatible = "motorola,mapphone-cpcap-adc",
        }, {
                .name          = "cpcap_battery",
                .of_compatible = "motorola,cpcap-battery",
        }, {
                .name          = "cpcap-charger",
                .of_compatible = "motorola,mapphone-cpcap-charger",
        }, {
                .name          = "cpcap-regulator",
                .of_compatible = "motorola,mapphone-cpcap-regulator",
        }, {
                .name          = "cpcap-rtc",
                .of_compatible = "motorola,cpcap-rtc",
        }, {
                .name          = "cpcap-pwrbutton",
                .of_compatible = "motorola,cpcap-pwrbutton",
        }, {
                .name          = "cpcap-usb-phy",
                .of_compatible = "motorola,mapphone-cpcap-usb-phy",
        }, {
                .name          = "cpcap-led",
                .id            = 0,
                .of_compatible = "motorola,cpcap-led-red",
        }, {
                .name          = "cpcap-led",
                .id            = 1,
                .of_compatible = "motorola,cpcap-led-green",
        }, {
                .name          = "cpcap-led",
                .id            = 2,
                .of_compatible = "motorola,cpcap-led-blue",
        }, {
                .name          = "cpcap-led",
                .id            = 3,
                .of_compatible = "motorola,cpcap-led-adl",
        }, {
                .name          = "cpcap-led",
                .id            = 4,
                .of_compatible = "motorola,cpcap-led-cp",
        }, {
                .name          = "cpcap-codec",
        }
};

static int cpcap_probe(struct spi_device *spi)
{
        struct cpcap_ddata *cpcap;
        int ret;

        cpcap = devm_kzalloc(&spi->dev, sizeof(*cpcap), GFP_KERNEL);
        if (!cpcap)
                return -ENOMEM;

        cpcap->spi = spi;
        spi_set_drvdata(spi, cpcap);

        spi->bits_per_word = 16;
        spi->mode = SPI_MODE_0 | SPI_CS_HIGH;

        ret = spi_setup(spi);
        if (ret)
                return ret;

        cpcap->regmap_conf = &cpcap_regmap_config;
        cpcap->regmap = devm_regmap_init_spi(spi, &cpcap_regmap_config);
        if (IS_ERR(cpcap->regmap)) {
                ret = PTR_ERR(cpcap->regmap);
                dev_err(&cpcap->spi->dev, "Failed to initialize regmap: %d\n",
                        ret);

                return ret;
        }

        ret = cpcap_check_revision(cpcap);
        if (ret) {
                dev_err(&cpcap->spi->dev, "Failed to detect CPCAP: %i\n", ret);
                return ret;
        }

        ret = cpcap_init_irq(cpcap);
        if (ret)
                return ret;

        /* Parent SPI controller uses DMA, CPCAP and child devices do not */
        spi->dev.coherent_dma_mask = 0;
        spi->dev.dma_mask = &spi->dev.coherent_dma_mask;

        return devm_mfd_add_devices(&spi->dev, 0, cpcap_mfd_devices,
                                    ARRAY_SIZE(cpcap_mfd_devices), NULL, 0, NULL);
}

static struct spi_driver cpcap_driver = {
        .driver = {
                .name = "cpcap-core",
                .of_match_table = cpcap_of_match,
                .pm = pm_sleep_ptr(&cpcap_pm),
        },
        .probe = cpcap_probe,
        .id_table = cpcap_spi_ids,
};
module_spi_driver(cpcap_driver);

MODULE_ALIAS("platform:cpcap");
MODULE_DESCRIPTION("CPCAP driver");
MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");
MODULE_LICENSE("GPL v2");