linux/drivers/i2c/busses/i2c-at91-core.c
Eugen Hristev 42f36457f9 i2c: at91: remote default value initialization
Platform data structs are initialized by default with zero values.
Thus it becomes redundant to initialize them manually to zero (false).
Remove extra false initialization for field members in structs.

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Reviewed-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-06 15:33:51 +01:00

376 lines
8.3 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
*
* Copyright (C) 2011 Weinmann Medical GmbH
* Author: Nikolaus Voss <n.voss@weinmann.de>
*
* Evolved from original work by:
* Copyright (C) 2004 Rick Bronson
* Converted to 2.6 by Andrew Victor <andrew@sanpeople.com>
*
* Borrowed heavily from original work by:
* Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/pinctrl/consumer.h>
#include "i2c-at91.h"
unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
{
return readl_relaxed(dev->base + reg);
}
void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val)
{
writel_relaxed(val, dev->base + reg);
}
void at91_disable_twi_interrupts(struct at91_twi_dev *dev)
{
at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK);
}
void at91_twi_irq_save(struct at91_twi_dev *dev)
{
dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK;
at91_disable_twi_interrupts(dev);
}
void at91_twi_irq_restore(struct at91_twi_dev *dev)
{
at91_twi_write(dev, AT91_TWI_IER, dev->imr);
}
void at91_init_twi_bus(struct at91_twi_dev *dev)
{
at91_disable_twi_interrupts(dev);
at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
if (dev->slave_detected)
at91_init_twi_bus_slave(dev);
else
at91_init_twi_bus_master(dev);
}
static struct at91_twi_pdata at91rm9200_config = {
.clk_max_div = 5,
.clk_offset = 3,
.has_unre_flag = true,
};
static struct at91_twi_pdata at91sam9261_config = {
.clk_max_div = 5,
.clk_offset = 4,
};
static struct at91_twi_pdata at91sam9260_config = {
.clk_max_div = 7,
.clk_offset = 4,
};
static struct at91_twi_pdata at91sam9g20_config = {
.clk_max_div = 7,
.clk_offset = 4,
};
static struct at91_twi_pdata at91sam9g10_config = {
.clk_max_div = 7,
.clk_offset = 4,
};
static const struct platform_device_id at91_twi_devtypes[] = {
{
.name = "i2c-at91rm9200",
.driver_data = (unsigned long) &at91rm9200_config,
}, {
.name = "i2c-at91sam9261",
.driver_data = (unsigned long) &at91sam9261_config,
}, {
.name = "i2c-at91sam9260",
.driver_data = (unsigned long) &at91sam9260_config,
}, {
.name = "i2c-at91sam9g20",
.driver_data = (unsigned long) &at91sam9g20_config,
}, {
.name = "i2c-at91sam9g10",
.driver_data = (unsigned long) &at91sam9g10_config,
}, {
/* sentinel */
}
};
#if defined(CONFIG_OF)
static struct at91_twi_pdata at91sam9x5_config = {
.clk_max_div = 7,
.clk_offset = 4,
};
static struct at91_twi_pdata sama5d4_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_hold_field = true,
.has_dig_filtr = true,
};
static struct at91_twi_pdata sama5d2_config = {
.clk_max_div = 7,
.clk_offset = 3,
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
.has_dig_filtr = true,
.has_adv_dig_filtr = true,
.has_ana_filtr = true,
};
static struct at91_twi_pdata sam9x60_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
.has_dig_filtr = true,
.has_adv_dig_filtr = true,
.has_ana_filtr = true,
};
static const struct of_device_id atmel_twi_dt_ids[] = {
{
.compatible = "atmel,at91rm9200-i2c",
.data = &at91rm9200_config,
}, {
.compatible = "atmel,at91sam9260-i2c",
.data = &at91sam9260_config,
}, {
.compatible = "atmel,at91sam9261-i2c",
.data = &at91sam9261_config,
}, {
.compatible = "atmel,at91sam9g20-i2c",
.data = &at91sam9g20_config,
}, {
.compatible = "atmel,at91sam9g10-i2c",
.data = &at91sam9g10_config,
}, {
.compatible = "atmel,at91sam9x5-i2c",
.data = &at91sam9x5_config,
}, {
.compatible = "atmel,sama5d4-i2c",
.data = &sama5d4_config,
}, {
.compatible = "atmel,sama5d2-i2c",
.data = &sama5d2_config,
}, {
.compatible = "microchip,sam9x60-i2c",
.data = &sam9x60_config,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
#endif
static struct at91_twi_pdata *at91_twi_get_driver_data(
struct platform_device *pdev)
{
if (pdev->dev.of_node) {
const struct of_device_id *match;
match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
if (!match)
return NULL;
return (struct at91_twi_pdata *)match->data;
}
return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
}
static int at91_twi_probe(struct platform_device *pdev)
{
struct at91_twi_dev *dev;
struct resource *mem;
int rc;
u32 phy_addr;
dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->dev = &pdev->dev;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem)
return -ENODEV;
phy_addr = mem->start;
dev->pdata = at91_twi_get_driver_data(pdev);
if (!dev->pdata)
return -ENODEV;
dev->base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(dev->base))
return PTR_ERR(dev->base);
dev->irq = platform_get_irq(pdev, 0);
if (dev->irq < 0)
return dev->irq;
platform_set_drvdata(pdev, dev);
dev->clk = devm_clk_get(dev->dev, NULL);
if (IS_ERR(dev->clk)) {
dev_err(dev->dev, "no clock defined\n");
return -ENODEV;
}
clk_prepare_enable(dev->clk);
snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91");
i2c_set_adapdata(&dev->adapter, dev);
dev->adapter.owner = THIS_MODULE;
dev->adapter.class = I2C_CLASS_DEPRECATED;
dev->adapter.dev.parent = dev->dev;
dev->adapter.nr = pdev->id;
dev->adapter.timeout = AT91_I2C_TIMEOUT;
dev->adapter.dev.of_node = pdev->dev.of_node;
dev->slave_detected = i2c_detect_slave_mode(&pdev->dev);
if (dev->slave_detected)
rc = at91_twi_probe_slave(pdev, phy_addr, dev);
else
rc = at91_twi_probe_master(pdev, phy_addr, dev);
if (rc)
return rc;
at91_init_twi_bus(dev);
pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(dev->dev);
pm_runtime_set_active(dev->dev);
pm_runtime_enable(dev->dev);
rc = i2c_add_numbered_adapter(&dev->adapter);
if (rc) {
clk_disable_unprepare(dev->clk);
pm_runtime_disable(dev->dev);
pm_runtime_set_suspended(dev->dev);
return rc;
}
dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n",
at91_twi_read(dev, AT91_TWI_VER));
return 0;
}
static int at91_twi_remove(struct platform_device *pdev)
{
struct at91_twi_dev *dev = platform_get_drvdata(pdev);
i2c_del_adapter(&dev->adapter);
clk_disable_unprepare(dev->clk);
pm_runtime_disable(dev->dev);
pm_runtime_set_suspended(dev->dev);
return 0;
}
#ifdef CONFIG_PM
static int at91_twi_runtime_suspend(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
clk_disable_unprepare(twi_dev->clk);
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static int at91_twi_runtime_resume(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
pinctrl_pm_select_default_state(dev);
return clk_prepare_enable(twi_dev->clk);
}
static int at91_twi_suspend_noirq(struct device *dev)
{
if (!pm_runtime_status_suspended(dev))
at91_twi_runtime_suspend(dev);
return 0;
}
static int at91_twi_resume_noirq(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
int ret;
if (!pm_runtime_status_suspended(dev)) {
ret = at91_twi_runtime_resume(dev);
if (ret)
return ret;
}
pm_runtime_mark_last_busy(dev);
pm_request_autosuspend(dev);
at91_init_twi_bus(twi_dev);
return 0;
}
static const struct dev_pm_ops at91_twi_pm = {
.suspend_noirq = at91_twi_suspend_noirq,
.resume_noirq = at91_twi_resume_noirq,
.runtime_suspend = at91_twi_runtime_suspend,
.runtime_resume = at91_twi_runtime_resume,
};
#define at91_twi_pm_ops (&at91_twi_pm)
#else
#define at91_twi_pm_ops NULL
#endif
static struct platform_driver at91_twi_driver = {
.probe = at91_twi_probe,
.remove = at91_twi_remove,
.id_table = at91_twi_devtypes,
.driver = {
.name = "at91_i2c",
.of_match_table = of_match_ptr(atmel_twi_dt_ids),
.pm = at91_twi_pm_ops,
},
};
static int __init at91_twi_init(void)
{
return platform_driver_register(&at91_twi_driver);
}
static void __exit at91_twi_exit(void)
{
platform_driver_unregister(&at91_twi_driver);
}
subsys_initcall(at91_twi_init);
module_exit(at91_twi_exit);
MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>");
MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:at91_i2c");