| /* |
| * Intel CHT Whiskey Cove PMIC I2C Master driver |
| * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com> |
| * |
| * Based on various non upstream patches to support the CHT Whiskey Cove PMIC: |
| * Copyright (C) 2011 - 2014 Intel Corporation. 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 as published by the Free Software Foundation, or (at your option) |
| * any later version. |
| * |
| * 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. |
| */ |
| |
| #include <linux/completion.h> |
| #include <linux/delay.h> |
| #include <linux/i2c.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/irqdomain.h> |
| #include <linux/mfd/intel_soc_pmic.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/slab.h> |
| |
| #define CHT_WC_I2C_CTRL 0x5e24 |
| #define CHT_WC_I2C_CTRL_WR BIT(0) |
| #define CHT_WC_I2C_CTRL_RD BIT(1) |
| #define CHT_WC_I2C_CLIENT_ADDR 0x5e25 |
| #define CHT_WC_I2C_REG_OFFSET 0x5e26 |
| #define CHT_WC_I2C_WRDATA 0x5e27 |
| #define CHT_WC_I2C_RDDATA 0x5e28 |
| |
| #define CHT_WC_EXTCHGRIRQ 0x6e0a |
| #define CHT_WC_EXTCHGRIRQ_CLIENT_IRQ BIT(0) |
| #define CHT_WC_EXTCHGRIRQ_WRITE_IRQ BIT(1) |
| #define CHT_WC_EXTCHGRIRQ_READ_IRQ BIT(2) |
| #define CHT_WC_EXTCHGRIRQ_NACK_IRQ BIT(3) |
| #define CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK ((u8)GENMASK(3, 1)) |
| #define CHT_WC_EXTCHGRIRQ_MSK 0x6e17 |
| |
| struct cht_wc_i2c_adap { |
| struct i2c_adapter adapter; |
| wait_queue_head_t wait; |
| struct irq_chip irqchip; |
| struct mutex adap_lock; |
| struct mutex irqchip_lock; |
| struct regmap *regmap; |
| struct irq_domain *irq_domain; |
| struct i2c_client *client; |
| int client_irq; |
| u8 irq_mask; |
| u8 old_irq_mask; |
| int read_data; |
| bool io_error; |
| bool done; |
| }; |
| |
| static irqreturn_t cht_wc_i2c_adap_thread_handler(int id, void *data) |
| { |
| struct cht_wc_i2c_adap *adap = data; |
| int ret, reg; |
| |
| mutex_lock(&adap->adap_lock); |
| |
| /* Read IRQs */ |
| ret = regmap_read(adap->regmap, CHT_WC_EXTCHGRIRQ, ®); |
| if (ret) { |
| dev_err(&adap->adapter.dev, "Error reading extchgrirq reg\n"); |
| mutex_unlock(&adap->adap_lock); |
| return IRQ_NONE; |
| } |
| |
| reg &= ~adap->irq_mask; |
| |
| /* Reads must be acked after reading the received data. */ |
| ret = regmap_read(adap->regmap, CHT_WC_I2C_RDDATA, &adap->read_data); |
| if (ret) |
| adap->io_error = true; |
| |
| /* |
| * Immediately ack IRQs, so that if new IRQs arrives while we're |
| * handling the previous ones our irq will re-trigger when we're done. |
| */ |
| ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ, reg); |
| if (ret) |
| dev_err(&adap->adapter.dev, "Error writing extchgrirq reg\n"); |
| |
| if (reg & CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK) { |
| adap->io_error |= !!(reg & CHT_WC_EXTCHGRIRQ_NACK_IRQ); |
| adap->done = true; |
| } |
| |
| mutex_unlock(&adap->adap_lock); |
| |
| if (reg & CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK) |
| wake_up(&adap->wait); |
| |
| /* |
| * Do NOT use handle_nested_irq here, the client irq handler will |
| * likely want to do i2c transfers and the i2c controller uses this |
| * interrupt handler as well, so running the client irq handler from |
| * this thread will cause things to lock up. |
| */ |
| if (reg & CHT_WC_EXTCHGRIRQ_CLIENT_IRQ) { |
| /* |
| * generic_handle_irq expects local IRQs to be disabled |
| * as normally it is called from interrupt context. |
| */ |
| local_irq_disable(); |
| generic_handle_irq(adap->client_irq); |
| local_irq_enable(); |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static u32 cht_wc_i2c_adap_master_func(struct i2c_adapter *adap) |
| { |
| /* This i2c adapter only supports SMBUS byte transfers */ |
| return I2C_FUNC_SMBUS_BYTE_DATA; |
| } |
| |
| static int cht_wc_i2c_adap_smbus_xfer(struct i2c_adapter *_adap, u16 addr, |
| unsigned short flags, char read_write, |
| u8 command, int size, |
| union i2c_smbus_data *data) |
| { |
| struct cht_wc_i2c_adap *adap = i2c_get_adapdata(_adap); |
| int ret; |
| |
| mutex_lock(&adap->adap_lock); |
| adap->io_error = false; |
| adap->done = false; |
| mutex_unlock(&adap->adap_lock); |
| |
| ret = regmap_write(adap->regmap, CHT_WC_I2C_CLIENT_ADDR, addr); |
| if (ret) |
| return ret; |
| |
| if (read_write == I2C_SMBUS_WRITE) { |
| ret = regmap_write(adap->regmap, CHT_WC_I2C_WRDATA, data->byte); |
| if (ret) |
| return ret; |
| } |
| |
| ret = regmap_write(adap->regmap, CHT_WC_I2C_REG_OFFSET, command); |
| if (ret) |
| return ret; |
| |
| ret = regmap_write(adap->regmap, CHT_WC_I2C_CTRL, |
| (read_write == I2C_SMBUS_WRITE) ? |
| CHT_WC_I2C_CTRL_WR : CHT_WC_I2C_CTRL_RD); |
| if (ret) |
| return ret; |
| |
| ret = wait_event_timeout(adap->wait, adap->done, msecs_to_jiffies(30)); |
| if (ret == 0) { |
| /* |
| * The CHT GPIO controller serializes all IRQs, sometimes |
| * causing significant delays, check status manually. |
| */ |
| cht_wc_i2c_adap_thread_handler(0, adap); |
| if (!adap->done) |
| return -ETIMEDOUT; |
| } |
| |
| ret = 0; |
| mutex_lock(&adap->adap_lock); |
| if (adap->io_error) |
| ret = -EIO; |
| else if (read_write == I2C_SMBUS_READ) |
| data->byte = adap->read_data; |
| mutex_unlock(&adap->adap_lock); |
| |
| return ret; |
| } |
| |
| static const struct i2c_algorithm cht_wc_i2c_adap_algo = { |
| .functionality = cht_wc_i2c_adap_master_func, |
| .smbus_xfer = cht_wc_i2c_adap_smbus_xfer, |
| }; |
| |
| /**** irqchip for the client connected to the extchgr i2c adapter ****/ |
| static void cht_wc_i2c_irq_lock(struct irq_data *data) |
| { |
| struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); |
| |
| mutex_lock(&adap->irqchip_lock); |
| } |
| |
| static void cht_wc_i2c_irq_sync_unlock(struct irq_data *data) |
| { |
| struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); |
| int ret; |
| |
| if (adap->irq_mask != adap->old_irq_mask) { |
| ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ_MSK, |
| adap->irq_mask); |
| if (ret == 0) |
| adap->old_irq_mask = adap->irq_mask; |
| else |
| dev_err(&adap->adapter.dev, "Error writing EXTCHGRIRQ_MSK\n"); |
| } |
| |
| mutex_unlock(&adap->irqchip_lock); |
| } |
| |
| static void cht_wc_i2c_irq_enable(struct irq_data *data) |
| { |
| struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); |
| |
| adap->irq_mask &= ~CHT_WC_EXTCHGRIRQ_CLIENT_IRQ; |
| } |
| |
| static void cht_wc_i2c_irq_disable(struct irq_data *data) |
| { |
| struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); |
| |
| adap->irq_mask |= CHT_WC_EXTCHGRIRQ_CLIENT_IRQ; |
| } |
| |
| static const struct irq_chip cht_wc_i2c_irq_chip = { |
| .irq_bus_lock = cht_wc_i2c_irq_lock, |
| .irq_bus_sync_unlock = cht_wc_i2c_irq_sync_unlock, |
| .irq_disable = cht_wc_i2c_irq_disable, |
| .irq_enable = cht_wc_i2c_irq_enable, |
| .name = "cht_wc_ext_chrg_irq_chip", |
| }; |
| |
| static const struct property_entry bq24190_props[] = { |
| PROPERTY_ENTRY_STRING("extcon-name", "cht_wcove_pwrsrc"), |
| PROPERTY_ENTRY_BOOL("omit-battery-class"), |
| PROPERTY_ENTRY_BOOL("disable-reset"), |
| { } |
| }; |
| |
| static int cht_wc_i2c_adap_i2c_probe(struct platform_device *pdev) |
| { |
| struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent); |
| struct cht_wc_i2c_adap *adap; |
| struct i2c_board_info board_info = { |
| .type = "bq24190", |
| .addr = 0x6b, |
| .properties = bq24190_props, |
| }; |
| int ret, reg, irq; |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) { |
| dev_err(&pdev->dev, "Error missing irq resource\n"); |
| return -EINVAL; |
| } |
| |
| adap = devm_kzalloc(&pdev->dev, sizeof(*adap), GFP_KERNEL); |
| if (!adap) |
| return -ENOMEM; |
| |
| init_waitqueue_head(&adap->wait); |
| mutex_init(&adap->adap_lock); |
| mutex_init(&adap->irqchip_lock); |
| adap->irqchip = cht_wc_i2c_irq_chip; |
| adap->regmap = pmic->regmap; |
| adap->adapter.owner = THIS_MODULE; |
| adap->adapter.class = I2C_CLASS_HWMON; |
| adap->adapter.algo = &cht_wc_i2c_adap_algo; |
| strlcpy(adap->adapter.name, "PMIC I2C Adapter", |
| sizeof(adap->adapter.name)); |
| adap->adapter.dev.parent = &pdev->dev; |
| |
| /* Clear and activate i2c-adapter interrupts, disable client IRQ */ |
| adap->old_irq_mask = adap->irq_mask = ~CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK; |
| |
| ret = regmap_read(adap->regmap, CHT_WC_I2C_RDDATA, ®); |
| if (ret) |
| return ret; |
| |
| ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ, ~adap->irq_mask); |
| if (ret) |
| return ret; |
| |
| ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ_MSK, adap->irq_mask); |
| if (ret) |
| return ret; |
| |
| /* Alloc and register client IRQ */ |
| adap->irq_domain = irq_domain_add_linear(pdev->dev.of_node, 1, |
| &irq_domain_simple_ops, NULL); |
| if (!adap->irq_domain) |
| return -ENOMEM; |
| |
| adap->client_irq = irq_create_mapping(adap->irq_domain, 0); |
| if (!adap->client_irq) { |
| ret = -ENOMEM; |
| goto remove_irq_domain; |
| } |
| |
| irq_set_chip_data(adap->client_irq, adap); |
| irq_set_chip_and_handler(adap->client_irq, &adap->irqchip, |
| handle_simple_irq); |
| |
| ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, |
| cht_wc_i2c_adap_thread_handler, |
| IRQF_ONESHOT, "PMIC I2C Adapter", adap); |
| if (ret) |
| goto remove_irq_domain; |
| |
| i2c_set_adapdata(&adap->adapter, adap); |
| ret = i2c_add_adapter(&adap->adapter); |
| if (ret) |
| goto remove_irq_domain; |
| |
| board_info.irq = adap->client_irq; |
| adap->client = i2c_new_device(&adap->adapter, &board_info); |
| if (!adap->client) { |
| ret = -ENOMEM; |
| goto del_adapter; |
| } |
| |
| platform_set_drvdata(pdev, adap); |
| return 0; |
| |
| del_adapter: |
| i2c_del_adapter(&adap->adapter); |
| remove_irq_domain: |
| irq_domain_remove(adap->irq_domain); |
| return ret; |
| } |
| |
| static int cht_wc_i2c_adap_i2c_remove(struct platform_device *pdev) |
| { |
| struct cht_wc_i2c_adap *adap = platform_get_drvdata(pdev); |
| |
| i2c_unregister_device(adap->client); |
| i2c_del_adapter(&adap->adapter); |
| irq_domain_remove(adap->irq_domain); |
| |
| return 0; |
| } |
| |
| static struct platform_device_id cht_wc_i2c_adap_id_table[] = { |
| { .name = "cht_wcove_ext_chgr" }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(platform, cht_wc_i2c_adap_id_table); |
| |
| static struct platform_driver cht_wc_i2c_adap_driver = { |
| .probe = cht_wc_i2c_adap_i2c_probe, |
| .remove = cht_wc_i2c_adap_i2c_remove, |
| .driver = { |
| .name = "cht_wcove_ext_chgr", |
| }, |
| .id_table = cht_wc_i2c_adap_id_table, |
| }; |
| module_platform_driver(cht_wc_i2c_adap_driver); |
| |
| MODULE_DESCRIPTION("Intel CHT Whiskey Cove PMIC I2C Master driver"); |
| MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); |
| MODULE_LICENSE("GPL"); |