diff options
Diffstat (limited to 'drivers/mfd/stmfx.c')
| -rw-r--r-- | drivers/mfd/stmfx.c | 565 |
1 files changed, 565 insertions, 0 deletions
diff --git a/drivers/mfd/stmfx.c b/drivers/mfd/stmfx.c new file mode 100644 index 000000000..b1ecd85ad --- /dev/null +++ b/drivers/mfd/stmfx.c @@ -0,0 +1,565 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for STMicroelectronics Multi-Function eXpander (STMFX) core + * + * Copyright (C) 2019 STMicroelectronics + * Author(s): Amelie Delaunay <amelie.delaunay@st.com>. + */ +#include <linux/bitfield.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/mfd/core.h> +#include <linux/mfd/stmfx.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> + +static bool stmfx_reg_volatile(struct device *dev, unsigned int reg) +{ + switch (reg) { + case STMFX_REG_SYS_CTRL: + case STMFX_REG_IRQ_SRC_EN: + case STMFX_REG_IRQ_PENDING: + case STMFX_REG_IRQ_GPI_PENDING1: + case STMFX_REG_IRQ_GPI_PENDING2: + case STMFX_REG_IRQ_GPI_PENDING3: + case STMFX_REG_GPIO_STATE1: + case STMFX_REG_GPIO_STATE2: + case STMFX_REG_GPIO_STATE3: + case STMFX_REG_IRQ_GPI_SRC1: + case STMFX_REG_IRQ_GPI_SRC2: + case STMFX_REG_IRQ_GPI_SRC3: + case STMFX_REG_GPO_SET1: + case STMFX_REG_GPO_SET2: + case STMFX_REG_GPO_SET3: + case STMFX_REG_GPO_CLR1: + case STMFX_REG_GPO_CLR2: + case STMFX_REG_GPO_CLR3: + return true; + default: + return false; + } +} + +static bool stmfx_reg_writeable(struct device *dev, unsigned int reg) +{ + return (reg >= STMFX_REG_SYS_CTRL); +} + +static const struct regmap_config stmfx_regmap_config = { + .reg_bits = 8, + .reg_stride = 1, + .val_bits = 8, + .max_register = STMFX_REG_MAX, + .volatile_reg = stmfx_reg_volatile, + .writeable_reg = stmfx_reg_writeable, + .cache_type = REGCACHE_RBTREE, +}; + +static const struct resource stmfx_pinctrl_resources[] = { + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_GPIO), +}; + +static const struct resource stmfx_idd_resources[] = { + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_IDD), + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_ERROR), +}; + +static const struct resource stmfx_ts_resources[] = { + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_DET), + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_NE), + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_TH), + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_FULL), + DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_OVF), +}; + +static struct mfd_cell stmfx_cells[] = { + { + .of_compatible = "st,stmfx-0300-pinctrl", + .name = "stmfx-pinctrl", + .resources = stmfx_pinctrl_resources, + .num_resources = ARRAY_SIZE(stmfx_pinctrl_resources), + }, + { + .of_compatible = "st,stmfx-0300-idd", + .name = "stmfx-idd", + .resources = stmfx_idd_resources, + .num_resources = ARRAY_SIZE(stmfx_idd_resources), + }, + { + .of_compatible = "st,stmfx-0300-ts", + .name = "stmfx-ts", + .resources = stmfx_ts_resources, + .num_resources = ARRAY_SIZE(stmfx_ts_resources), + }, +}; + +static u8 stmfx_func_to_mask(u32 func) +{ + u8 mask = 0; + + if (func & STMFX_FUNC_GPIO) + mask |= STMFX_REG_SYS_CTRL_GPIO_EN; + + if ((func & STMFX_FUNC_ALTGPIO_LOW) || (func & STMFX_FUNC_ALTGPIO_HIGH)) + mask |= STMFX_REG_SYS_CTRL_ALTGPIO_EN; + + if (func & STMFX_FUNC_TS) + mask |= STMFX_REG_SYS_CTRL_TS_EN; + + if (func & STMFX_FUNC_IDD) + mask |= STMFX_REG_SYS_CTRL_IDD_EN; + + return mask; +} + +int stmfx_function_enable(struct stmfx *stmfx, u32 func) +{ + u32 sys_ctrl; + u8 mask; + int ret; + + ret = regmap_read(stmfx->map, STMFX_REG_SYS_CTRL, &sys_ctrl); + if (ret) + return ret; + + /* + * IDD and TS have priority in STMFX FW, so if IDD and TS are enabled, + * ALTGPIO function is disabled by STMFX FW. If IDD or TS is enabled, + * the number of aGPIO available decreases. To avoid GPIO management + * disturbance, abort IDD or TS function enable in this case. + */ + if (((func & STMFX_FUNC_IDD) || (func & STMFX_FUNC_TS)) && + (sys_ctrl & STMFX_REG_SYS_CTRL_ALTGPIO_EN)) { + dev_err(stmfx->dev, "ALTGPIO function already enabled\n"); + return -EBUSY; + } + + /* If TS is enabled, aGPIO[3:0] cannot be used */ + if ((func & STMFX_FUNC_ALTGPIO_LOW) && + (sys_ctrl & STMFX_REG_SYS_CTRL_TS_EN)) { + dev_err(stmfx->dev, "TS in use, aGPIO[3:0] unavailable\n"); + return -EBUSY; + } + + /* If IDD is enabled, aGPIO[7:4] cannot be used */ + if ((func & STMFX_FUNC_ALTGPIO_HIGH) && + (sys_ctrl & STMFX_REG_SYS_CTRL_IDD_EN)) { + dev_err(stmfx->dev, "IDD in use, aGPIO[7:4] unavailable\n"); + return -EBUSY; + } + + mask = stmfx_func_to_mask(func); + + return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, mask); +} +EXPORT_SYMBOL_GPL(stmfx_function_enable); + +int stmfx_function_disable(struct stmfx *stmfx, u32 func) +{ + u8 mask = stmfx_func_to_mask(func); + + return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, 0); +} +EXPORT_SYMBOL_GPL(stmfx_function_disable); + +static void stmfx_irq_bus_lock(struct irq_data *data) +{ + struct stmfx *stmfx = irq_data_get_irq_chip_data(data); + + mutex_lock(&stmfx->lock); +} + +static void stmfx_irq_bus_sync_unlock(struct irq_data *data) +{ + struct stmfx *stmfx = irq_data_get_irq_chip_data(data); + + regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, stmfx->irq_src); + + mutex_unlock(&stmfx->lock); +} + +static void stmfx_irq_mask(struct irq_data *data) +{ + struct stmfx *stmfx = irq_data_get_irq_chip_data(data); + + stmfx->irq_src &= ~BIT(data->hwirq % 8); +} + +static void stmfx_irq_unmask(struct irq_data *data) +{ + struct stmfx *stmfx = irq_data_get_irq_chip_data(data); + + stmfx->irq_src |= BIT(data->hwirq % 8); +} + +static struct irq_chip stmfx_irq_chip = { + .name = "stmfx-core", + .irq_bus_lock = stmfx_irq_bus_lock, + .irq_bus_sync_unlock = stmfx_irq_bus_sync_unlock, + .irq_mask = stmfx_irq_mask, + .irq_unmask = stmfx_irq_unmask, +}; + +static irqreturn_t stmfx_irq_handler(int irq, void *data) +{ + struct stmfx *stmfx = data; + unsigned long bits; + u32 pending, ack; + int n, ret; + + ret = regmap_read(stmfx->map, STMFX_REG_IRQ_PENDING, &pending); + if (ret) + return IRQ_NONE; + + /* + * There is no ACK for GPIO, MFX_REG_IRQ_PENDING_GPIO is a logical OR + * of MFX_REG_IRQ_GPI _PENDING1/_PENDING2/_PENDING3 + */ + ack = pending & ~BIT(STMFX_REG_IRQ_SRC_EN_GPIO); + if (ack) { + ret = regmap_write(stmfx->map, STMFX_REG_IRQ_ACK, ack); + if (ret) + return IRQ_NONE; + } + + bits = pending; + for_each_set_bit(n, &bits, STMFX_REG_IRQ_SRC_MAX) + handle_nested_irq(irq_find_mapping(stmfx->irq_domain, n)); + + return IRQ_HANDLED; +} + +static int stmfx_irq_map(struct irq_domain *d, unsigned int virq, + irq_hw_number_t hwirq) +{ + irq_set_chip_data(virq, d->host_data); + irq_set_chip_and_handler(virq, &stmfx_irq_chip, handle_simple_irq); + irq_set_nested_thread(virq, 1); + irq_set_noprobe(virq); + + return 0; +} + +static void stmfx_irq_unmap(struct irq_domain *d, unsigned int virq) +{ + irq_set_chip_and_handler(virq, NULL, NULL); + irq_set_chip_data(virq, NULL); +} + +static const struct irq_domain_ops stmfx_irq_ops = { + .map = stmfx_irq_map, + .unmap = stmfx_irq_unmap, +}; + +static void stmfx_irq_exit(struct i2c_client *client) +{ + struct stmfx *stmfx = i2c_get_clientdata(client); + int hwirq; + + for (hwirq = 0; hwirq < STMFX_REG_IRQ_SRC_MAX; hwirq++) + irq_dispose_mapping(irq_find_mapping(stmfx->irq_domain, hwirq)); + + irq_domain_remove(stmfx->irq_domain); +} + +static int stmfx_irq_init(struct i2c_client *client) +{ + struct stmfx *stmfx = i2c_get_clientdata(client); + u32 irqoutpin = 0, irqtrigger; + int ret; + + stmfx->irq_domain = irq_domain_add_simple(stmfx->dev->of_node, + STMFX_REG_IRQ_SRC_MAX, 0, + &stmfx_irq_ops, stmfx); + if (!stmfx->irq_domain) { + dev_err(stmfx->dev, "Failed to create IRQ domain\n"); + return -EINVAL; + } + + if (!of_property_read_bool(stmfx->dev->of_node, "drive-open-drain")) + irqoutpin |= STMFX_REG_IRQ_OUT_PIN_TYPE; + + irqtrigger = irq_get_trigger_type(client->irq); + if ((irqtrigger & IRQ_TYPE_EDGE_RISING) || + (irqtrigger & IRQ_TYPE_LEVEL_HIGH)) + irqoutpin |= STMFX_REG_IRQ_OUT_PIN_POL; + + ret = regmap_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN, irqoutpin); + if (ret) + goto irq_exit; + + ret = devm_request_threaded_irq(stmfx->dev, client->irq, + NULL, stmfx_irq_handler, + irqtrigger | IRQF_ONESHOT, + "stmfx", stmfx); + if (ret) + goto irq_exit; + + stmfx->irq = client->irq; + + return 0; + +irq_exit: + stmfx_irq_exit(client); + + return ret; +} + +static int stmfx_chip_reset(struct stmfx *stmfx) +{ + int ret; + + ret = regmap_write(stmfx->map, STMFX_REG_SYS_CTRL, + STMFX_REG_SYS_CTRL_SWRST); + if (ret) + return ret; + + msleep(STMFX_BOOT_TIME_MS); + + return ret; +} + +static int stmfx_chip_init(struct i2c_client *client) +{ + struct stmfx *stmfx = i2c_get_clientdata(client); + u32 id; + u8 version[2]; + int ret; + + stmfx->vdd = devm_regulator_get_optional(&client->dev, "vdd"); + ret = PTR_ERR_OR_ZERO(stmfx->vdd); + if (ret) { + stmfx->vdd = NULL; + if (ret != -ENODEV) + return dev_err_probe(&client->dev, ret, "Failed to get VDD regulator\n"); + } + + if (stmfx->vdd) { + ret = regulator_enable(stmfx->vdd); + if (ret) { + dev_err(&client->dev, "VDD enable failed: %d\n", ret); + return ret; + } + } + + ret = regmap_read(stmfx->map, STMFX_REG_CHIP_ID, &id); + if (ret) { + dev_err(&client->dev, "Error reading chip ID: %d\n", ret); + goto err; + } + + /* + * Check that ID is the complement of the I2C address: + * STMFX I2C address follows the 7-bit format (MSB), that's why + * client->addr is shifted. + * + * STMFX_I2C_ADDR| STMFX | Linux + * input pin | I2C device address | I2C device address + *--------------------------------------------------------- + * 0 | b: 1000 010x h:0x84 | 0x42 + * 1 | b: 1000 011x h:0x86 | 0x43 + */ + if (FIELD_GET(STMFX_REG_CHIP_ID_MASK, ~id) != (client->addr << 1)) { + dev_err(&client->dev, "Unknown chip ID: %#x\n", id); + ret = -EINVAL; + goto err; + } + + ret = regmap_bulk_read(stmfx->map, STMFX_REG_FW_VERSION_MSB, + version, ARRAY_SIZE(version)); + if (ret) { + dev_err(&client->dev, "Error reading FW version: %d\n", ret); + goto err; + } + + dev_info(&client->dev, "STMFX id: %#x, fw version: %x.%02x\n", + id, version[0], version[1]); + + ret = stmfx_chip_reset(stmfx); + if (ret) { + dev_err(&client->dev, "Failed to reset chip: %d\n", ret); + goto err; + } + + return 0; + +err: + if (stmfx->vdd) + regulator_disable(stmfx->vdd); + + return ret; +} + +static void stmfx_chip_exit(struct i2c_client *client) +{ + struct stmfx *stmfx = i2c_get_clientdata(client); + + regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, 0); + regmap_write(stmfx->map, STMFX_REG_SYS_CTRL, 0); + + if (stmfx->vdd) { + int ret; + + ret = regulator_disable(stmfx->vdd); + if (ret) + dev_err(&client->dev, + "Failed to disable vdd regulator: %pe\n", + ERR_PTR(ret)); + } +} + +static int stmfx_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct stmfx *stmfx; + int ret; + + stmfx = devm_kzalloc(dev, sizeof(*stmfx), GFP_KERNEL); + if (!stmfx) + return -ENOMEM; + + i2c_set_clientdata(client, stmfx); + + stmfx->dev = dev; + + stmfx->map = devm_regmap_init_i2c(client, &stmfx_regmap_config); + if (IS_ERR(stmfx->map)) { + ret = PTR_ERR(stmfx->map); + dev_err(dev, "Failed to allocate register map: %d\n", ret); + return ret; + } + + mutex_init(&stmfx->lock); + + ret = stmfx_chip_init(client); + if (ret) { + if (ret == -ETIMEDOUT) + return -EPROBE_DEFER; + return ret; + } + + if (client->irq < 0) { + dev_err(dev, "Failed to get IRQ: %d\n", client->irq); + ret = client->irq; + goto err_chip_exit; + } + + ret = stmfx_irq_init(client); + if (ret) + goto err_chip_exit; + + ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, + stmfx_cells, ARRAY_SIZE(stmfx_cells), NULL, + 0, stmfx->irq_domain); + if (ret) + goto err_irq_exit; + + return 0; + +err_irq_exit: + stmfx_irq_exit(client); +err_chip_exit: + stmfx_chip_exit(client); + + return ret; +} + +static void stmfx_remove(struct i2c_client *client) +{ + stmfx_irq_exit(client); + + stmfx_chip_exit(client); +} + +#ifdef CONFIG_PM_SLEEP +static int stmfx_suspend(struct device *dev) +{ + struct stmfx *stmfx = dev_get_drvdata(dev); + int ret; + + ret = regmap_raw_read(stmfx->map, STMFX_REG_SYS_CTRL, + &stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl)); + if (ret) + return ret; + + ret = regmap_raw_read(stmfx->map, STMFX_REG_IRQ_OUT_PIN, + &stmfx->bkp_irqoutpin, + sizeof(stmfx->bkp_irqoutpin)); + if (ret) + return ret; + + disable_irq(stmfx->irq); + + if (stmfx->vdd) + return regulator_disable(stmfx->vdd); + + return 0; +} + +static int stmfx_resume(struct device *dev) +{ + struct stmfx *stmfx = dev_get_drvdata(dev); + int ret; + + if (stmfx->vdd) { + ret = regulator_enable(stmfx->vdd); + if (ret) { + dev_err(stmfx->dev, + "VDD enable failed: %d\n", ret); + return ret; + } + } + + /* Reset STMFX - supply has been stopped during suspend */ + ret = stmfx_chip_reset(stmfx); + if (ret) { + dev_err(stmfx->dev, "Failed to reset chip: %d\n", ret); + return ret; + } + + ret = regmap_raw_write(stmfx->map, STMFX_REG_SYS_CTRL, + &stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl)); + if (ret) + return ret; + + ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN, + &stmfx->bkp_irqoutpin, + sizeof(stmfx->bkp_irqoutpin)); + if (ret) + return ret; + + ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, + &stmfx->irq_src, sizeof(stmfx->irq_src)); + if (ret) + return ret; + + enable_irq(stmfx->irq); + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(stmfx_dev_pm_ops, stmfx_suspend, stmfx_resume); + +static const struct of_device_id stmfx_of_match[] = { + { .compatible = "st,stmfx-0300", }, + {}, +}; +MODULE_DEVICE_TABLE(of, stmfx_of_match); + +static struct i2c_driver stmfx_driver = { + .driver = { + .name = "stmfx-core", + .of_match_table = stmfx_of_match, + .pm = &stmfx_dev_pm_ops, + }, + .probe = stmfx_probe, + .remove = stmfx_remove, +}; +module_i2c_driver(stmfx_driver); + +MODULE_DESCRIPTION("STMFX core driver"); +MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>"); +MODULE_LICENSE("GPL v2"); |