diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-platdrv.c | 498 |
1 files changed, 498 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c new file mode 100644 index 000000000..b5750fd85 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -0,0 +1,498 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Synopsys DesignWare I2C adapter driver. + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + */ +#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 <linux/suspend.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); + struct i2c_timings *t = &dev->timings; + 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 (t->bus_freq_hz) { + 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) +{ + struct i2c_timings *t = &dev->timings; + + dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY; + + dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | + DW_IC_CON_RESTART_EN; + + dev->mode = DW_IC_MASTER; + + switch (t->bus_freq_hz) { + 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 void i2c_dw_configure_slave(struct dw_i2c_dev *dev) +{ + dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY; + + dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL | + DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED; + + dev->mode = DW_IC_SLAVE; +} + +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 void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev) +{ + pm_runtime_disable(dev->dev); + + if (dev->pm_disabled) + pm_runtime_put_noidle(dev->dev); +} + +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; + struct i2c_timings *t; + u32 acpi_speed; + struct resource *mem; + int i, irq, ret; + static const int supported_speeds[] = { + 0, 100000, 400000, 1000000, 3400000 + }; + + 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); + } + + t = &dev->timings; + if (pdata) + t->bus_freq_hz = pdata->i2c_scl_freq; + else + i2c_parse_fw_timings(&pdev->dev, t, false); + + acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev); + /* + * Some DSTDs use a non standard speed, round down to the lowest + * standard speed. + */ + for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) { + if (acpi_speed < supported_speeds[i]) + break; + } + acpi_speed = supported_speeds[i - 1]; + + /* + * Find bus speed from the "clock-frequency" device property, ACPI + * or by using fast mode if neither is set. + */ + if (acpi_speed && t->bus_freq_hz) + t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed); + else if (acpi_speed || t->bus_freq_hz) + t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed); + else + t->bus_freq_hz = 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 (t->bus_freq_hz != 100000 && t->bus_freq_hz != 400000 && + t->bus_freq_hz != 1000000 && t->bus_freq_hz != 3400000) { + dev_err(&pdev->dev, + "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n", + t->bus_freq_hz); + ret = -EINVAL; + goto exit_reset; + } + + ret = i2c_dw_probe_lock_support(dev); + if (ret) + goto exit_reset; + + if (i2c_detect_slave_mode(&pdev->dev)) + i2c_dw_configure_slave(dev); + else + i2c_dw_configure_master(dev); + + dev->clk = devm_clk_get(&pdev->dev, NULL); + if (!i2c_dw_prepare_clk(dev, true)) { + u64 clk_khz; + + dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz; + clk_khz = dev->get_clk_rate_khz(dev); + + if (!dev->sda_hold_time && t->sda_hold_ns) + dev->sda_hold_time = + div_u64(clk_khz * t->sda_hold_ns + 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; + + dev_pm_set_driver_flags(&pdev->dev, + DPM_FLAG_SMART_PREPARE | + DPM_FLAG_SMART_SUSPEND | + DPM_FLAG_LEAVE_SUSPENDED); + + /* The code below assumes runtime PM to be disabled. */ + WARN_ON(pm_runtime_enabled(&pdev->dev)); + + pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + + if (dev->pm_disabled) + pm_runtime_get_noresume(&pdev->dev); + + pm_runtime_enable(&pdev->dev); + + if (dev->mode == DW_IC_SLAVE) + ret = i2c_dw_probe_slave(dev); + else + ret = i2c_dw_probe(dev); + + if (ret) + goto exit_probe; + + return ret; + +exit_probe: + dw_i2c_plat_pm_cleanup(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); + + dev->disable(dev); + + pm_runtime_dont_use_autosuspend(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); + dw_i2c_plat_pm_cleanup(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) +{ + /* + * If the ACPI companion device object is present for this device, it + * may be accessed during suspend and resume of other devices via I2C + * operation regions, so tell the PM core and middle layers to avoid + * skipping system suspend/resume callbacks for it in that case. + */ + return !has_acpi_companion(dev); +} + +static void dw_i2c_plat_complete(struct device *dev) +{ + /* + * The device can only be in runtime suspend at this point if it has not + * been resumed throughout the ending system suspend/resume cycle, so if + * the platform firmware might mess up with it, request the runtime PM + * framework to resume it. + */ + if (pm_runtime_suspended(dev) && pm_resume_via_firmware()) + 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 dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + if (i_dev->pm_disabled) + return 0; + + i_dev->disable(i_dev); + i2c_dw_prepare_clk(i_dev, false); + + return 0; +} + +static int dw_i2c_plat_resume(struct device *dev) +{ + struct dw_i2c_dev *i_dev = dev_get_drvdata(dev); + + if (!i_dev->pm_disabled) + i2c_dw_prepare_clk(i_dev, true); + + i_dev->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_LATE_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"); |