diff options
Diffstat (limited to 'drivers/mfd/qcom-i2c-pmic.c')
-rw-r--r-- | drivers/mfd/qcom-i2c-pmic.c | 664 |
1 files changed, 664 insertions, 0 deletions
diff --git a/drivers/mfd/qcom-i2c-pmic.c b/drivers/mfd/qcom-i2c-pmic.c new file mode 100644 index 000000000000..ea5ac972b096 --- /dev/null +++ b/drivers/mfd/qcom-i2c-pmic.c @@ -0,0 +1,664 @@ +/* Copyright (c) 2016 The Linux Foundation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#define pr_fmt(fmt) "I2C PMIC: %s: " fmt, __func__ + +#include <linux/bitops.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of_platform.h> +#include <linux/pinctrl/consumer.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define I2C_INTR_STATUS_BASE 0x0550 +#define INT_RT_STS_OFFSET 0x10 +#define INT_SET_TYPE_OFFSET 0x11 +#define INT_POL_HIGH_OFFSET 0x12 +#define INT_POL_LOW_OFFSET 0x13 +#define INT_LATCHED_CLR_OFFSET 0x14 +#define INT_EN_SET_OFFSET 0x15 +#define INT_EN_CLR_OFFSET 0x16 +#define INT_LATCHED_STS_OFFSET 0x18 +#define INT_PENDING_STS_OFFSET 0x19 +#define INT_MID_SEL_OFFSET 0x1A +#define INT_MID_SEL_MASK GENMASK(1, 0) +#define INT_PRIORITY_OFFSET 0x1B +#define INT_PRIORITY_BIT BIT(0) + +enum { + IRQ_SET_TYPE = 0, + IRQ_POL_HIGH, + IRQ_POL_LOW, + IRQ_LATCHED_CLR, /* not needed but makes life easy */ + IRQ_EN_SET, + IRQ_MAX_REGS, +}; + +struct i2c_pmic_periph { + void *data; + u16 addr; + u8 cached[IRQ_MAX_REGS]; + u8 synced[IRQ_MAX_REGS]; + u8 wake; + struct mutex lock; +}; + +struct i2c_pmic { + struct device *dev; + struct regmap *regmap; + struct irq_domain *domain; + struct i2c_pmic_periph *periph; + struct pinctrl *pinctrl; + const char *pinctrl_name; + int num_periphs; +}; + +static void i2c_pmic_irq_bus_lock(struct irq_data *d) +{ + struct i2c_pmic_periph *periph = irq_data_get_irq_chip_data(d); + + mutex_lock(&periph->lock); +} + +static void i2c_pmic_sync_type_polarity(struct i2c_pmic *chip, + struct i2c_pmic_periph *periph) +{ + int rc; + + /* did any irq type change? */ + if (periph->cached[IRQ_SET_TYPE] ^ periph->synced[IRQ_SET_TYPE]) { + rc = regmap_write(chip->regmap, + periph->addr | INT_SET_TYPE_OFFSET, + periph->cached[IRQ_SET_TYPE]); + if (rc < 0) { + pr_err("Couldn't set periph 0x%04x irqs 0x%02x type rc=%d\n", + periph->addr, periph->cached[IRQ_SET_TYPE], rc); + return; + } + + periph->synced[IRQ_SET_TYPE] = periph->cached[IRQ_SET_TYPE]; + } + + /* did any polarity high change? */ + if (periph->cached[IRQ_POL_HIGH] ^ periph->synced[IRQ_POL_HIGH]) { + rc = regmap_write(chip->regmap, + periph->addr | INT_POL_HIGH_OFFSET, + periph->cached[IRQ_POL_HIGH]); + if (rc < 0) { + pr_err("Couldn't set periph 0x%04x irqs 0x%02x polarity high rc=%d\n", + periph->addr, periph->cached[IRQ_POL_HIGH], rc); + return; + } + + periph->synced[IRQ_POL_HIGH] = periph->cached[IRQ_POL_HIGH]; + } + + /* did any polarity low change? */ + if (periph->cached[IRQ_POL_LOW] ^ periph->synced[IRQ_POL_LOW]) { + rc = regmap_write(chip->regmap, + periph->addr | INT_POL_LOW_OFFSET, + periph->cached[IRQ_POL_LOW]); + if (rc < 0) { + pr_err("Couldn't set periph 0x%04x irqs 0x%02x polarity low rc=%d\n", + periph->addr, periph->cached[IRQ_POL_LOW], rc); + return; + } + + periph->synced[IRQ_POL_LOW] = periph->cached[IRQ_POL_LOW]; + } +} + +static void i2c_pmic_sync_enable(struct i2c_pmic *chip, + struct i2c_pmic_periph *periph) +{ + u8 en_set, en_clr; + int rc; + + /* determine which irqs were enabled and which were disabled */ + en_clr = periph->synced[IRQ_EN_SET] & ~periph->cached[IRQ_EN_SET]; + en_set = ~periph->synced[IRQ_EN_SET] & periph->cached[IRQ_EN_SET]; + + /* were any irqs disabled? */ + if (en_clr) { + rc = regmap_write(chip->regmap, + periph->addr | INT_EN_CLR_OFFSET, en_clr); + if (rc < 0) { + pr_err("Couldn't disable periph 0x%04x irqs 0x%02x rc=%d\n", + periph->addr, en_clr, rc); + return; + } + } + + /* were any irqs enabled? */ + if (en_set) { + rc = regmap_write(chip->regmap, + periph->addr | INT_EN_SET_OFFSET, en_set); + if (rc < 0) { + pr_err("Couldn't enable periph 0x%04x irqs 0x%02x rc=%d\n", + periph->addr, en_set, rc); + return; + } + } + + /* irq enabled status was written to hardware */ + periph->synced[IRQ_EN_SET] = periph->cached[IRQ_EN_SET]; +} + +static void i2c_pmic_irq_bus_sync_unlock(struct irq_data *d) +{ + struct i2c_pmic_periph *periph = irq_data_get_irq_chip_data(d); + struct i2c_pmic *chip = periph->data; + + i2c_pmic_sync_type_polarity(chip, periph); + i2c_pmic_sync_enable(chip, periph); + mutex_unlock(&periph->lock); +} + +static void i2c_pmic_irq_disable(struct irq_data *d) +{ + struct i2c_pmic_periph *periph = irq_data_get_irq_chip_data(d); + + periph->cached[IRQ_EN_SET] &= ~d->hwirq & 0xFF; +} + +static void i2c_pmic_irq_enable(struct irq_data *d) +{ + struct i2c_pmic_periph *periph = irq_data_get_irq_chip_data(d); + + periph->cached[IRQ_EN_SET] |= d->hwirq & 0xFF; +} + +static int i2c_pmic_irq_set_type(struct irq_data *d, unsigned int irq_type) +{ + struct i2c_pmic_periph *periph = irq_data_get_irq_chip_data(d); + + switch (irq_type) { + case IRQ_TYPE_EDGE_RISING: + periph->cached[IRQ_SET_TYPE] |= d->hwirq & 0xFF; + periph->cached[IRQ_POL_HIGH] |= d->hwirq & 0xFF; + periph->cached[IRQ_POL_LOW] &= ~d->hwirq & 0xFF; + break; + case IRQ_TYPE_EDGE_FALLING: + periph->cached[IRQ_SET_TYPE] |= d->hwirq & 0xFF; + periph->cached[IRQ_POL_HIGH] &= ~d->hwirq & 0xFF; + periph->cached[IRQ_POL_LOW] |= d->hwirq & 0xFF; + break; + case IRQ_TYPE_EDGE_BOTH: + periph->cached[IRQ_SET_TYPE] |= d->hwirq & 0xFF; + periph->cached[IRQ_POL_HIGH] |= d->hwirq & 0xFF; + periph->cached[IRQ_POL_LOW] |= d->hwirq & 0xFF; + break; + case IRQ_TYPE_LEVEL_HIGH: + periph->cached[IRQ_SET_TYPE] &= ~d->hwirq & 0xFF; + periph->cached[IRQ_POL_HIGH] |= d->hwirq & 0xFF; + periph->cached[IRQ_POL_LOW] &= ~d->hwirq & 0xFF; + break; + case IRQ_TYPE_LEVEL_LOW: + periph->cached[IRQ_SET_TYPE] &= ~d->hwirq & 0xFF; + periph->cached[IRQ_POL_HIGH] &= ~d->hwirq & 0xFF; + periph->cached[IRQ_POL_LOW] |= d->hwirq & 0xFF; + break; + default: + pr_err("irq type 0x%04x is not supported\n", irq_type); + return -EINVAL; + } + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int i2c_pmic_irq_set_wake(struct irq_data *d, unsigned int on) +{ + struct i2c_pmic_periph *periph = irq_data_get_irq_chip_data(d); + + if (on) + periph->wake |= d->hwirq & 0xFF; + else + periph->wake &= ~d->hwirq & 0xFF; + + return 0; +} +#else +#define i2c_pmic_irq_set_wake NULL +#endif + +static struct irq_chip i2c_pmic_irq_chip = { + .name = "i2c_pmic_irq_chip", + .irq_bus_lock = i2c_pmic_irq_bus_lock, + .irq_bus_sync_unlock = i2c_pmic_irq_bus_sync_unlock, + .irq_disable = i2c_pmic_irq_disable, + .irq_enable = i2c_pmic_irq_enable, + .irq_set_type = i2c_pmic_irq_set_type, + .irq_set_wake = i2c_pmic_irq_set_wake, +}; + +static struct i2c_pmic_periph *i2c_pmic_find_periph(struct i2c_pmic *chip, + irq_hw_number_t hwirq) +{ + int i; + + for (i = 0; i < chip->num_periphs; i++) + if (chip->periph[i].addr == (hwirq & 0xFF00)) + return &chip->periph[i]; + + pr_err_ratelimited("Couldn't find periph struct for hwirq 0x%04lx\n", + hwirq); + return NULL; +} + +static int i2c_pmic_domain_map(struct irq_domain *d, unsigned int virq, + irq_hw_number_t hwirq) +{ + struct i2c_pmic *chip = d->host_data; + struct i2c_pmic_periph *periph = i2c_pmic_find_periph(chip, hwirq); + + if (!periph) + return -ENODEV; + + irq_set_chip_data(virq, periph); + irq_set_chip_and_handler(virq, &i2c_pmic_irq_chip, handle_level_irq); + irq_set_nested_thread(virq, 1); + irq_set_noprobe(virq); + return 0; +} + +static int i2c_pmic_domain_xlate(struct irq_domain *d, + struct device_node *ctrlr, const u32 *intspec, + unsigned int intsize, unsigned long *out_hwirq, + unsigned int *out_type) +{ + if (intsize != 3) + return -EINVAL; + + if (intspec[0] > 0xFF || intspec[1] > 0x7 || + intspec[2] > IRQ_TYPE_SENSE_MASK) + return -EINVAL; + + /* + * Interrupt specifiers are triplets + * <peripheral-address, irq-number, IRQ_TYPE_*> + * + * peripheral-address - The base address of the peripheral + * irq-number - The zero based bit position of the peripheral's + * interrupt registers corresponding to the irq + * where the LSB is 0 and the MSB is 7 + * IRQ_TYPE_* - Please refer to linux/irq.h + */ + *out_hwirq = intspec[0] << 8 | BIT(intspec[1]); + *out_type = intspec[2] & IRQ_TYPE_SENSE_MASK; + + return 0; +} + +static const struct irq_domain_ops i2c_pmic_domain_ops = { + .map = i2c_pmic_domain_map, + .xlate = i2c_pmic_domain_xlate, +}; + +static void i2c_pmic_irq_ack_now(struct i2c_pmic *chip, u16 hwirq) +{ + int rc; + + rc = regmap_write(chip->regmap, + (hwirq & 0xFF00) | INT_LATCHED_CLR_OFFSET, + hwirq & 0xFF); + if (rc < 0) + pr_err_ratelimited("Couldn't ack 0x%04x rc=%d\n", hwirq, rc); +} + +static void i2c_pmic_irq_disable_now(struct i2c_pmic *chip, u16 hwirq) +{ + struct i2c_pmic_periph *periph = i2c_pmic_find_periph(chip, hwirq); + int rc; + + if (!periph) + return; + + mutex_lock(&periph->lock); + periph->cached[IRQ_EN_SET] &= ~hwirq & 0xFF; + + rc = regmap_write(chip->regmap, + (hwirq & 0xFF00) | INT_EN_CLR_OFFSET, + hwirq & 0xFF); + if (rc < 0) { + pr_err_ratelimited("Couldn't disable irq 0x%04x rc=%d\n", + hwirq, rc); + goto unlock; + } + + periph->synced[IRQ_EN_SET] = periph->cached[IRQ_EN_SET]; + +unlock: + mutex_unlock(&periph->lock); +} + +static void i2c_pmic_periph_status_handler(struct i2c_pmic *chip, + u16 periph_address, u8 periph_status) +{ + unsigned int hwirq, virq; + int i; + + while (periph_status) { + i = ffs(periph_status) - 1; + periph_status &= ~BIT(i); + hwirq = periph_address | BIT(i); + virq = irq_find_mapping(chip->domain, hwirq); + if (virq == 0) { + pr_err_ratelimited("Couldn't find mapping; disabling 0x%04x\n", + hwirq); + i2c_pmic_irq_disable_now(chip, hwirq); + continue; + } + + handle_nested_irq(virq); + i2c_pmic_irq_ack_now(chip, hwirq); + } +} + +static void i2c_pmic_summary_status_handler(struct i2c_pmic *chip, + struct i2c_pmic_periph *periph, + u8 summary_status) +{ + unsigned int periph_status; + int rc, i; + + while (summary_status) { + i = ffs(summary_status) - 1; + summary_status &= ~BIT(i); + + rc = regmap_read(chip->regmap, + periph[i].addr | INT_LATCHED_STS_OFFSET, + &periph_status); + if (rc < 0) { + pr_err_ratelimited("Couldn't read 0x%04x | INT_LATCHED_STS rc=%d\n", + periph[i].addr, rc); + continue; + } + + i2c_pmic_periph_status_handler(chip, periph[i].addr, + periph_status); + } +} + +static irqreturn_t i2c_pmic_irq_handler(int irq, void *dev_id) +{ + struct i2c_pmic *chip = dev_id; + struct i2c_pmic_periph *periph; + unsigned int summary_status; + int rc, i; + + for (i = 0; i < DIV_ROUND_UP(chip->num_periphs, BITS_PER_BYTE); i++) { + rc = regmap_read(chip->regmap, I2C_INTR_STATUS_BASE + i, + &summary_status); + if (rc < 0) { + pr_err_ratelimited("Couldn't read I2C_INTR_STATUS%d rc=%d\n", + i, rc); + continue; + } + + if (summary_status == 0) + continue; + + periph = &chip->periph[i * 8]; + i2c_pmic_summary_status_handler(chip, periph, summary_status); + } + + return IRQ_HANDLED; +} + +static int i2c_pmic_parse_dt(struct i2c_pmic *chip) +{ + struct device_node *node = chip->dev->of_node; + int rc, i; + u32 temp; + + if (!node) { + pr_err("missing device tree\n"); + return -EINVAL; + } + + chip->num_periphs = of_property_count_u32_elems(node, + "qcom,periph-map"); + if (chip->num_periphs < 0) { + pr_err("missing qcom,periph-map property rc=%d\n", + chip->num_periphs); + return chip->num_periphs; + } + + if (chip->num_periphs == 0) { + pr_err("qcom,periph-map must contain at least one address\n"); + return -EINVAL; + } + + chip->periph = devm_kcalloc(chip->dev, chip->num_periphs, + sizeof(*chip->periph), GFP_KERNEL); + if (!chip->periph) + return -ENOMEM; + + for (i = 0; i < chip->num_periphs; i++) { + rc = of_property_read_u32_index(node, "qcom,periph-map", + i, &temp); + if (rc < 0) { + pr_err("Couldn't read qcom,periph-map[%d] rc=%d\n", + i, rc); + return rc; + } + + chip->periph[i].addr = (u16)(temp << 8); + chip->periph[i].data = chip; + mutex_init(&chip->periph[i].lock); + } + + of_property_read_string(node, "pinctrl-names", &chip->pinctrl_name); + + return rc; +} + +static int i2c_pmic_determine_initial_status(struct i2c_pmic *chip) +{ + int rc, i; + + for (i = 0; i < chip->num_periphs; i++) { + rc = regmap_bulk_read(chip->regmap, + chip->periph[i].addr | INT_SET_TYPE_OFFSET, + chip->periph[i].cached, IRQ_MAX_REGS); + if (rc < 0) { + pr_err("Couldn't read irq data rc=%d\n", rc); + return rc; + } + + memcpy(chip->periph[i].synced, chip->periph[i].cached, + IRQ_MAX_REGS * sizeof(*chip->periph[i].synced)); + } + + return 0; +} + +static struct regmap_config i2c_pmic_regmap_config = { + .reg_bits = 16, + .val_bits = 8, + .max_register = 0xFFFF, +}; + +static int i2c_pmic_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_pmic *chip; + int rc = 0; + + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->dev = &client->dev; + chip->regmap = devm_regmap_init_i2c(client, &i2c_pmic_regmap_config); + if (!chip->regmap) + return -ENODEV; + + i2c_set_clientdata(client, chip); + if (!of_property_read_bool(chip->dev->of_node, "interrupt-controller")) + goto probe_children; + + chip->domain = irq_domain_add_tree(client->dev.of_node, + &i2c_pmic_domain_ops, chip); + if (!chip->domain) { + rc = -ENOMEM; + goto cleanup; + } + + rc = i2c_pmic_parse_dt(chip); + if (rc < 0) { + pr_err("Couldn't parse device tree rc=%d\n", rc); + goto cleanup; + } + + rc = i2c_pmic_determine_initial_status(chip); + if (rc < 0) { + pr_err("Couldn't determine initial status rc=%d\n", rc); + goto cleanup; + } + + if (chip->pinctrl_name) { + chip->pinctrl = devm_pinctrl_get_select(chip->dev, + chip->pinctrl_name); + if (IS_ERR(chip->pinctrl)) { + pr_err("Couldn't select %s pinctrl rc=%ld\n", + chip->pinctrl_name, PTR_ERR(chip->pinctrl)); + rc = PTR_ERR(chip->pinctrl); + goto cleanup; + } + } + + rc = devm_request_threaded_irq(&client->dev, client->irq, NULL, + i2c_pmic_irq_handler, + IRQF_ONESHOT | IRQF_SHARED, + "i2c_pmic_stat_irq", chip); + if (rc < 0) { + pr_err("Couldn't request irq %d rc=%d\n", client->irq, rc); + goto cleanup; + } + + enable_irq_wake(client->irq); + +probe_children: + of_platform_populate(chip->dev->of_node, NULL, NULL, chip->dev); + pr_info("I2C PMIC probe successful\n"); + return rc; + +cleanup: + if (chip->domain) + irq_domain_remove(chip->domain); + i2c_set_clientdata(client, NULL); + return rc; +} + +static int i2c_pmic_remove(struct i2c_client *client) +{ + struct i2c_pmic *chip = i2c_get_clientdata(client); + + of_platform_depopulate(chip->dev); + if (chip->domain) + irq_domain_remove(chip->domain); + i2c_set_clientdata(client, NULL); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int i2c_pmic_suspend(struct device *dev) +{ + struct i2c_pmic *chip = dev_get_drvdata(dev); + struct i2c_pmic_periph *periph; + int rc = 0, i; + + for (i = 0; i < chip->num_periphs; i++) { + periph = &chip->periph[i]; + + rc = regmap_write(chip->regmap, + periph->addr | INT_EN_CLR_OFFSET, 0xFF); + if (rc < 0) { + pr_err_ratelimited("Couldn't clear 0x%04x irqs rc=%d\n", + periph->addr, rc); + continue; + } + + rc = regmap_write(chip->regmap, + periph->addr | INT_EN_SET_OFFSET, + periph->wake); + if (rc < 0) + pr_err_ratelimited("Couldn't enable 0x%04x wake irqs 0x%02x rc=%d\n", + periph->addr, periph->wake, rc); + } + + return rc; +} + +static int i2c_pmic_resume(struct device *dev) +{ + struct i2c_pmic *chip = dev_get_drvdata(dev); + struct i2c_pmic_periph *periph; + int rc = 0, i; + + for (i = 0; i < chip->num_periphs; i++) { + periph = &chip->periph[i]; + + rc = regmap_write(chip->regmap, + periph->addr | INT_EN_CLR_OFFSET, 0xFF); + if (rc < 0) { + pr_err("Couldn't clear 0x%04x irqs rc=%d\n", + periph->addr, rc); + continue; + } + + rc = regmap_write(chip->regmap, + periph->addr | INT_EN_SET_OFFSET, + periph->synced[IRQ_EN_SET]); + if (rc < 0) + pr_err("Couldn't restore 0x%04x synced irqs 0x%02x rc=%d\n", + periph->addr, periph->synced[IRQ_EN_SET], rc); + } + + return rc; +} +#endif +static SIMPLE_DEV_PM_OPS(i2c_pmic_pm_ops, i2c_pmic_suspend, i2c_pmic_resume); + +static const struct of_device_id i2c_pmic_match_table[] = { + { .compatible = "qcom,i2c-pmic", }, + { }, +}; + +static const struct i2c_device_id i2c_pmic_id[] = { + { "i2c-pmic", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, i2c_pmic_id); + +static struct i2c_driver i2c_pmic_driver = { + .driver = { + .name = "i2c_pmic", + .owner = THIS_MODULE, + .pm = &i2c_pmic_pm_ops, + .of_match_table = i2c_pmic_match_table, + }, + .probe = i2c_pmic_probe, + .remove = i2c_pmic_remove, + .id_table = i2c_pmic_id, +}; + +module_i2c_driver(i2c_pmic_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("i2c:i2c_pmic"); |