/* * Synopsys DesignWare I2C adapter driver (master only). * * Based on the TI DAVINCI I2C adapter driver. * * Copyright (C) 2006 Texas Instruments. * Copyright (C) 2007 MontaVista Software Inc. * Copyright (C) 2009 Provigent Ltd. * * ---------------------------------------------------------------------------- * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, 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/acpi.h> #include <linux/clk-provider.h> #include <linux/clk.h> #include <linux/delay.h> #include <linux/dmi.h> #include <linux/err.h> #include <linux/errno.h> #include <linux/i2c.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_data/i2c-designware.h> #include <linux/platform_device.h> #include <linux/pm.h> #include <linux/pm_runtime.h> #include <linux/property.h> #include <linux/reset.h> #include <linux/sched.h> #include <linux/slab.h> #include "i2c-designware-core.h" static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) { return clk_get_rate(dev->clk)/1000; } #ifdef CONFIG_ACPI /* * The HCNT/LCNT information coming from ACPI should be the most accurate * for given platform. However, some systems get it wrong. On such systems * we get better results by calculating those based on the input clock. */ static const struct dmi_system_id dw_i2c_no_acpi_params[] = { { .ident = "Dell Inspiron 7348", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"), }, }, { } }; static void dw_i2c_acpi_params(struct platform_device *pdev, char method[], u16 *hcnt, u16 *lcnt, u32 *sda_hold) { struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; acpi_handle handle = ACPI_HANDLE(&pdev->dev); union acpi_object *obj; if (dmi_check_system(dw_i2c_no_acpi_params)) return; if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf))) return; obj = (union acpi_object *)buf.pointer; if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) { const union acpi_object *objs = obj->package.elements; *hcnt = (u16)objs[0].integer.value; *lcnt = (u16)objs[1].integer.value; *sda_hold = (u32)objs[2].integer.value; } kfree(buf.pointer); } static int dw_i2c_acpi_configure(struct platform_device *pdev) { struct dw_i2c_dev *dev = platform_get_drvdata(pdev); u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0; acpi_handle handle = ACPI_HANDLE(&pdev->dev); const struct acpi_device_id *id; struct acpi_device *adev; const char *uid; dev->adapter.nr = -1; dev->tx_fifo_depth = 32; dev->rx_fifo_depth = 32; /* * Try to get SDA hold time and *CNT values from an ACPI method for * selected speed modes. */ dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht); dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht); dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht); dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht); switch (dev->clk_freq) { case 100000: dev->sda_hold_time = ss_ht; break; case 1000000: dev->sda_hold_time = fp_ht; break; case 3400000: dev->sda_hold_time = hs_ht; break; case 400000: default: dev->sda_hold_time = fs_ht; break; } id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev); if (id && id->driver_data) dev->flags |= (u32)id->driver_data; if (acpi_bus_get_device(handle, &adev)) return -ENODEV; /* * Cherrytrail I2C7 gets used for the PMIC which gets accessed * through ACPI opregions during late suspend / early resume * disable pm for it. */ uid = adev->pnp.unique_id; if ((dev->flags & MODEL_CHERRYTRAIL) && !strcmp(uid, "7")) dev->pm_disabled = true; return 0; } static const struct acpi_device_id dw_i2c_acpi_match[] = { { "INT33C2", 0 }, { "INT33C3", 0 }, { "INT3432", 0 }, { "INT3433", 0 }, { "80860F41", 0 }, { "808622C1", MODEL_CHERRYTRAIL }, { "AMD0010", ACCESS_INTR_MASK }, { "AMDI0010", ACCESS_INTR_MASK }, { "AMDI0510", 0 }, { "APMC0D0F", 0 }, { "HISI02A1", 0 }, { "HISI02A2", 0 }, { } }; MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match); #else static inline int dw_i2c_acpi_configure(struct platform_device *pdev) { return -ENODEV; } #endif static void i2c_dw_configure_master(struct dw_i2c_dev *dev) { dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | DW_IC_CON_RESTART_EN; switch (dev->clk_freq) { case 100000: dev->master_cfg |= DW_IC_CON_SPEED_STD; break; case 3400000: dev->master_cfg |= DW_IC_CON_SPEED_HIGH; break; default: dev->master_cfg |= DW_IC_CON_SPEED_FAST; } } static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare) { if (IS_ERR(i_dev->clk)) return PTR_ERR(i_dev->clk); if (prepare) return clk_prepare_enable(i_dev->clk); clk_disable_unprepare(i_dev->clk); return 0; } static void dw_i2c_set_fifo_size(struct dw_i2c_dev *dev, int id) { u32 param, tx_fifo_depth, rx_fifo_depth; /* * Try to detect the FIFO depth if not set by interface driver, * the depth could be from 2 to 256 from HW spec. */ param = i2c_dw_read_comp_param(dev); tx_fifo_depth = ((param >> 16) & 0xff) + 1; rx_fifo_depth = ((param >> 8) & 0xff) + 1; if (!dev->tx_fifo_depth) { dev->tx_fifo_depth = tx_fifo_depth; dev->rx_fifo_depth = rx_fifo_depth; dev->adapter.nr = id; } else if (tx_fifo_depth >= 2) { dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth, tx_fifo_depth); dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth, rx_fifo_depth); } } static int dw_i2c_plat_probe(struct platform_device *pdev) { struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev); struct i2c_adapter *adap; struct dw_i2c_dev *dev; u32 acpi_speed, ht = 0; struct resource *mem; int irq, ret; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL); if (!dev) return -ENOMEM; mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); dev->base = devm_ioremap_resource(&pdev->dev, mem); if (IS_ERR(dev->base)) return PTR_ERR(dev->base); dev->dev = &pdev->dev; dev->irq = irq; platform_set_drvdata(pdev, dev); dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL); if (IS_ERR(dev->rst)) { if (PTR_ERR(dev->rst) == -EPROBE_DEFER) return -EPROBE_DEFER; } else { reset_control_deassert(dev->rst); } if (pdata) { dev->clk_freq = pdata->i2c_scl_freq; } else { device_property_read_u32(&pdev->dev, "i2c-sda-hold-time-ns", &ht); device_property_read_u32(&pdev->dev, "i2c-sda-falling-time-ns", &dev->sda_falling_time); device_property_read_u32(&pdev->dev, "i2c-scl-falling-time-ns", &dev->scl_falling_time); device_property_read_u32(&pdev->dev, "clock-frequency", &dev->clk_freq); } acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev); /* * Find bus speed from the "clock-frequency" device property, ACPI * or by using fast mode if neither is set. */ if (acpi_speed && dev->clk_freq) dev->clk_freq = min(dev->clk_freq, acpi_speed); else if (acpi_speed || dev->clk_freq) dev->clk_freq = max(dev->clk_freq, acpi_speed); else dev->clk_freq = 400000; if (has_acpi_companion(&pdev->dev)) dw_i2c_acpi_configure(pdev); /* * Only standard mode at 100kHz, fast mode at 400kHz, * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported. */ if (dev->clk_freq != 100000 && dev->clk_freq != 400000 && dev->clk_freq != 1000000 && dev->clk_freq != 3400000) { dev_err(&pdev->dev, "Only 100kHz, 400kHz, 1MHz and 3.4MHz supported"); ret = -EINVAL; goto exit_reset; } ret = i2c_dw_probe_lock_support(dev); if (ret) goto exit_reset; dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY; i2c_dw_configure_master(dev); dev->clk = devm_clk_get(&pdev->dev, NULL); if (!i2c_dw_plat_prepare_clk(dev, true)) { dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; if (!dev->sda_hold_time && ht) dev->sda_hold_time = div_u64( (u64)dev->get_clk_rate_khz(dev) * ht + 500000, 1000000); } dw_i2c_set_fifo_size(dev, pdev->id); adap = &dev->adapter; adap->owner = THIS_MODULE; adap->class = I2C_CLASS_DEPRECATED; ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev)); adap->dev.of_node = pdev->dev.of_node; if (dev->pm_disabled) { pm_runtime_forbid(&pdev->dev); } else { pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); } ret = i2c_dw_probe(dev); if (ret) goto exit_probe; return ret; exit_probe: if (!dev->pm_disabled) pm_runtime_disable(&pdev->dev); exit_reset: if (!IS_ERR_OR_NULL(dev->rst)) reset_control_assert(dev->rst); return ret; } static int dw_i2c_plat_remove(struct platform_device *pdev) { struct dw_i2c_dev *dev = platform_get_drvdata(pdev); pm_runtime_get_sync(&pdev->dev); i2c_del_adapter(&dev->adapter); i2c_dw_disable(dev); pm_runtime_dont_use_autosuspend(&pdev->dev); pm_runtime_put_sync(&pdev->dev); if (!dev->pm_disabled) pm_runtime_disable(&pdev->dev); if (!IS_ERR_OR_NULL(dev->rst)) reset_control_assert(dev->rst); i2c_dw_remove_lock_support(dev); return 0; } #ifdef CONFIG_OF static const struct of_device_id dw_i2c_of_match[] = { { .compatible = "snps,designware-i2c", }, {}, }; MODULE_DEVICE_TABLE(of, dw_i2c_of_match); #endif #ifdef CONFIG_PM_SLEEP static int dw_i2c_plat_prepare(struct device *dev) { return pm_runtime_suspended(dev); } static void dw_i2c_plat_complete(struct device *dev) { if (dev->power.direct_complete) pm_request_resume(dev); } #else #define dw_i2c_plat_prepare NULL #define dw_i2c_plat_complete NULL #endif #ifdef CONFIG_PM static int dw_i2c_plat_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev); i2c_dw_disable(i_dev); i2c_dw_plat_prepare_clk(i_dev, false); return 0; } static int dw_i2c_plat_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev); i2c_dw_plat_prepare_clk(i_dev, true); i2c_dw_init(i_dev); return 0; } static const struct dev_pm_ops dw_i2c_dev_pm_ops = { .prepare = dw_i2c_plat_prepare, .complete = dw_i2c_plat_complete, SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume) SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL) }; #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops) #else #define DW_I2C_DEV_PMOPS NULL #endif /* Work with hotplug and coldplug */ MODULE_ALIAS("platform:i2c_designware"); static struct platform_driver dw_i2c_driver = { .probe = dw_i2c_plat_probe, .remove = dw_i2c_plat_remove, .driver = { .name = "i2c_designware", .of_match_table = of_match_ptr(dw_i2c_of_match), .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match), .pm = DW_I2C_DEV_PMOPS, }, }; static int __init dw_i2c_init_driver(void) { return platform_driver_register(&dw_i2c_driver); } subsys_initcall(dw_i2c_init_driver); static void __exit dw_i2c_exit_driver(void) { platform_driver_unregister(&dw_i2c_driver); } module_exit(dw_i2c_exit_driver); MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>"); MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter"); MODULE_LICENSE("GPL");