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|
// 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;
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 I2C_MAX_STANDARD_MODE_FREQ:
dev->sda_hold_time = ss_ht;
break;
case I2C_MAX_FAST_MODE_PLUS_FREQ:
dev->sda_hold_time = fp_ht;
break;
case I2C_MAX_HIGH_SPEED_MODE_FREQ:
dev->sda_hold_time = hs_ht;
break;
case I2C_MAX_FAST_MODE_FREQ:
default:
dev->sda_hold_time = fs_ht;
break;
}
return 0;
}
static const struct acpi_device_id dw_i2c_acpi_match[] = {
{ "INT33C2", 0 },
{ "INT33C3", 0 },
{ "INT3432", 0 },
{ "INT3433", 0 },
{ "80860F41", ACCESS_NO_IRQ_SUSPEND },
{ "808622C1", ACCESS_NO_IRQ_SUSPEND | MODEL_CHERRYTRAIL },
{ "AMD0010", ACCESS_INTR_MASK },
{ "AMDI0010", ACCESS_INTR_MASK },
{ "AMDI0510", 0 },
{ "APMC0D0F", 0 },
{ "HISI02A1", 0 },
{ "HISI02A2", 0 },
{ "HISI02A3", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
#else
static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
{
return -ENODEV;
}
#endif
#ifdef CONFIG_OF
#define MSCC_ICPU_CFG_TWI_DELAY 0x0
#define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0)
#define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0x4
static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev)
{
writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE,
dev->ext + MSCC_ICPU_CFG_TWI_DELAY);
return 0;
}
static int dw_i2c_of_configure(struct platform_device *pdev)
{
struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
switch (dev->flags & MODEL_MASK) {
case MODEL_MSCC_OCELOT:
dev->ext = devm_platform_ioremap_resource(pdev, 1);
if (!IS_ERR(dev->ext))
dev->set_sda_hold_time = mscc_twi_set_sda_hold_time;
break;
default:
break;
}
return 0;
}
static const struct of_device_id dw_i2c_of_match[] = {
{ .compatible = "snps,designware-i2c", },
{ .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
{},
};
MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
#else
static inline int dw_i2c_of_configure(struct platform_device *pdev)
{
return -ENODEV;
}
#endif
static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
{
pm_runtime_disable(dev->dev);
if (dev->shared_with_punit)
pm_runtime_put_noidle(dev->dev);
}
static const u32 supported_speeds[] = {
I2C_MAX_HIGH_SPEED_MODE_FREQ,
I2C_MAX_FAST_MODE_PLUS_FREQ,
I2C_MAX_FAST_MODE_FREQ,
I2C_MAX_STANDARD_MODE_FREQ,
};
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;
int i, 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;
dev->base = devm_platform_ioremap_resource(pdev, 0);
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))
return PTR_ERR(dev->rst);
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 = 0; i < ARRAY_SIZE(supported_speeds); i++) {
if (acpi_speed >=
|