forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
369 lines
8.7 KiB
369 lines
8.7 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* drivers/rtc/rtc-v3020.c |
|
* |
|
* Copyright (C) 2006 8D Technologies inc. |
|
* Copyright (C) 2004 Compulab Ltd. |
|
* |
|
* Driver for the V3020 RTC |
|
* |
|
* Changelog: |
|
* |
|
* 10-May-2006: Raphael Assenat <[email protected]> |
|
* - Converted to platform driver |
|
* - Use the generic rtc class |
|
* |
|
* ??-???-2004: Someone at Compulab |
|
* - Initial driver creation. |
|
*/ |
|
#include <linux/platform_device.h> |
|
#include <linux/module.h> |
|
#include <linux/init.h> |
|
#include <linux/rtc.h> |
|
#include <linux/types.h> |
|
#include <linux/bcd.h> |
|
#include <linux/platform_data/rtc-v3020.h> |
|
#include <linux/delay.h> |
|
#include <linux/gpio.h> |
|
#include <linux/slab.h> |
|
|
|
#include <linux/io.h> |
|
|
|
#undef DEBUG |
|
|
|
struct v3020; |
|
|
|
struct v3020_chip_ops { |
|
int (*map_io)(struct v3020 *chip, struct platform_device *pdev, |
|
struct v3020_platform_data *pdata); |
|
void (*unmap_io)(struct v3020 *chip); |
|
unsigned char (*read_bit)(struct v3020 *chip); |
|
void (*write_bit)(struct v3020 *chip, unsigned char bit); |
|
}; |
|
|
|
#define V3020_CS 0 |
|
#define V3020_WR 1 |
|
#define V3020_RD 2 |
|
#define V3020_IO 3 |
|
|
|
struct v3020 { |
|
/* MMIO access */ |
|
void __iomem *ioaddress; |
|
int leftshift; |
|
|
|
/* GPIO access */ |
|
struct gpio *gpio; |
|
|
|
const struct v3020_chip_ops *ops; |
|
|
|
struct rtc_device *rtc; |
|
}; |
|
|
|
|
|
static int v3020_mmio_map(struct v3020 *chip, struct platform_device *pdev, |
|
struct v3020_platform_data *pdata) |
|
{ |
|
if (pdev->num_resources != 1) |
|
return -EBUSY; |
|
|
|
if (pdev->resource[0].flags != IORESOURCE_MEM) |
|
return -EBUSY; |
|
|
|
chip->leftshift = pdata->leftshift; |
|
chip->ioaddress = ioremap(pdev->resource[0].start, 1); |
|
if (chip->ioaddress == NULL) |
|
return -EBUSY; |
|
|
|
return 0; |
|
} |
|
|
|
static void v3020_mmio_unmap(struct v3020 *chip) |
|
{ |
|
iounmap(chip->ioaddress); |
|
} |
|
|
|
static void v3020_mmio_write_bit(struct v3020 *chip, unsigned char bit) |
|
{ |
|
writel(bit << chip->leftshift, chip->ioaddress); |
|
} |
|
|
|
static unsigned char v3020_mmio_read_bit(struct v3020 *chip) |
|
{ |
|
return !!(readl(chip->ioaddress) & (1 << chip->leftshift)); |
|
} |
|
|
|
static const struct v3020_chip_ops v3020_mmio_ops = { |
|
.map_io = v3020_mmio_map, |
|
.unmap_io = v3020_mmio_unmap, |
|
.read_bit = v3020_mmio_read_bit, |
|
.write_bit = v3020_mmio_write_bit, |
|
}; |
|
|
|
static struct gpio v3020_gpio[] = { |
|
{ 0, GPIOF_OUT_INIT_HIGH, "RTC CS"}, |
|
{ 0, GPIOF_OUT_INIT_HIGH, "RTC WR"}, |
|
{ 0, GPIOF_OUT_INIT_HIGH, "RTC RD"}, |
|
{ 0, GPIOF_OUT_INIT_HIGH, "RTC IO"}, |
|
}; |
|
|
|
static int v3020_gpio_map(struct v3020 *chip, struct platform_device *pdev, |
|
struct v3020_platform_data *pdata) |
|
{ |
|
int err; |
|
|
|
v3020_gpio[V3020_CS].gpio = pdata->gpio_cs; |
|
v3020_gpio[V3020_WR].gpio = pdata->gpio_wr; |
|
v3020_gpio[V3020_RD].gpio = pdata->gpio_rd; |
|
v3020_gpio[V3020_IO].gpio = pdata->gpio_io; |
|
|
|
err = gpio_request_array(v3020_gpio, ARRAY_SIZE(v3020_gpio)); |
|
|
|
if (!err) |
|
chip->gpio = v3020_gpio; |
|
|
|
return err; |
|
} |
|
|
|
static void v3020_gpio_unmap(struct v3020 *chip) |
|
{ |
|
gpio_free_array(v3020_gpio, ARRAY_SIZE(v3020_gpio)); |
|
} |
|
|
|
static void v3020_gpio_write_bit(struct v3020 *chip, unsigned char bit) |
|
{ |
|
gpio_direction_output(chip->gpio[V3020_IO].gpio, bit); |
|
gpio_set_value(chip->gpio[V3020_CS].gpio, 0); |
|
gpio_set_value(chip->gpio[V3020_WR].gpio, 0); |
|
udelay(1); |
|
gpio_set_value(chip->gpio[V3020_WR].gpio, 1); |
|
gpio_set_value(chip->gpio[V3020_CS].gpio, 1); |
|
} |
|
|
|
static unsigned char v3020_gpio_read_bit(struct v3020 *chip) |
|
{ |
|
int bit; |
|
|
|
gpio_direction_input(chip->gpio[V3020_IO].gpio); |
|
gpio_set_value(chip->gpio[V3020_CS].gpio, 0); |
|
gpio_set_value(chip->gpio[V3020_RD].gpio, 0); |
|
udelay(1); |
|
bit = !!gpio_get_value(chip->gpio[V3020_IO].gpio); |
|
udelay(1); |
|
gpio_set_value(chip->gpio[V3020_RD].gpio, 1); |
|
gpio_set_value(chip->gpio[V3020_CS].gpio, 1); |
|
|
|
return bit; |
|
} |
|
|
|
static const struct v3020_chip_ops v3020_gpio_ops = { |
|
.map_io = v3020_gpio_map, |
|
.unmap_io = v3020_gpio_unmap, |
|
.read_bit = v3020_gpio_read_bit, |
|
.write_bit = v3020_gpio_write_bit, |
|
}; |
|
|
|
static void v3020_set_reg(struct v3020 *chip, unsigned char address, |
|
unsigned char data) |
|
{ |
|
int i; |
|
unsigned char tmp; |
|
|
|
tmp = address; |
|
for (i = 0; i < 4; i++) { |
|
chip->ops->write_bit(chip, (tmp & 1)); |
|
tmp >>= 1; |
|
udelay(1); |
|
} |
|
|
|
/* Commands dont have data */ |
|
if (!V3020_IS_COMMAND(address)) { |
|
for (i = 0; i < 8; i++) { |
|
chip->ops->write_bit(chip, (data & 1)); |
|
data >>= 1; |
|
udelay(1); |
|
} |
|
} |
|
} |
|
|
|
static unsigned char v3020_get_reg(struct v3020 *chip, unsigned char address) |
|
{ |
|
unsigned int data = 0; |
|
int i; |
|
|
|
for (i = 0; i < 4; i++) { |
|
chip->ops->write_bit(chip, (address & 1)); |
|
address >>= 1; |
|
udelay(1); |
|
} |
|
|
|
for (i = 0; i < 8; i++) { |
|
data >>= 1; |
|
if (chip->ops->read_bit(chip)) |
|
data |= 0x80; |
|
udelay(1); |
|
} |
|
|
|
return data; |
|
} |
|
|
|
static int v3020_read_time(struct device *dev, struct rtc_time *dt) |
|
{ |
|
struct v3020 *chip = dev_get_drvdata(dev); |
|
int tmp; |
|
|
|
/* Copy the current time to ram... */ |
|
v3020_set_reg(chip, V3020_CMD_CLOCK2RAM, 0); |
|
|
|
/* ...and then read constant values. */ |
|
tmp = v3020_get_reg(chip, V3020_SECONDS); |
|
dt->tm_sec = bcd2bin(tmp); |
|
tmp = v3020_get_reg(chip, V3020_MINUTES); |
|
dt->tm_min = bcd2bin(tmp); |
|
tmp = v3020_get_reg(chip, V3020_HOURS); |
|
dt->tm_hour = bcd2bin(tmp); |
|
tmp = v3020_get_reg(chip, V3020_MONTH_DAY); |
|
dt->tm_mday = bcd2bin(tmp); |
|
tmp = v3020_get_reg(chip, V3020_MONTH); |
|
dt->tm_mon = bcd2bin(tmp) - 1; |
|
tmp = v3020_get_reg(chip, V3020_WEEK_DAY); |
|
dt->tm_wday = bcd2bin(tmp); |
|
tmp = v3020_get_reg(chip, V3020_YEAR); |
|
dt->tm_year = bcd2bin(tmp)+100; |
|
|
|
dev_dbg(dev, "\n%s : Read RTC values\n", __func__); |
|
dev_dbg(dev, "tm_hour: %i\n", dt->tm_hour); |
|
dev_dbg(dev, "tm_min : %i\n", dt->tm_min); |
|
dev_dbg(dev, "tm_sec : %i\n", dt->tm_sec); |
|
dev_dbg(dev, "tm_year: %i\n", dt->tm_year); |
|
dev_dbg(dev, "tm_mon : %i\n", dt->tm_mon); |
|
dev_dbg(dev, "tm_mday: %i\n", dt->tm_mday); |
|
dev_dbg(dev, "tm_wday: %i\n", dt->tm_wday); |
|
|
|
return 0; |
|
} |
|
|
|
|
|
static int v3020_set_time(struct device *dev, struct rtc_time *dt) |
|
{ |
|
struct v3020 *chip = dev_get_drvdata(dev); |
|
|
|
dev_dbg(dev, "\n%s : Setting RTC values\n", __func__); |
|
dev_dbg(dev, "tm_sec : %i\n", dt->tm_sec); |
|
dev_dbg(dev, "tm_min : %i\n", dt->tm_min); |
|
dev_dbg(dev, "tm_hour: %i\n", dt->tm_hour); |
|
dev_dbg(dev, "tm_mday: %i\n", dt->tm_mday); |
|
dev_dbg(dev, "tm_wday: %i\n", dt->tm_wday); |
|
dev_dbg(dev, "tm_year: %i\n", dt->tm_year); |
|
|
|
/* Write all the values to ram... */ |
|
v3020_set_reg(chip, V3020_SECONDS, bin2bcd(dt->tm_sec)); |
|
v3020_set_reg(chip, V3020_MINUTES, bin2bcd(dt->tm_min)); |
|
v3020_set_reg(chip, V3020_HOURS, bin2bcd(dt->tm_hour)); |
|
v3020_set_reg(chip, V3020_MONTH_DAY, bin2bcd(dt->tm_mday)); |
|
v3020_set_reg(chip, V3020_MONTH, bin2bcd(dt->tm_mon + 1)); |
|
v3020_set_reg(chip, V3020_WEEK_DAY, bin2bcd(dt->tm_wday)); |
|
v3020_set_reg(chip, V3020_YEAR, bin2bcd(dt->tm_year % 100)); |
|
|
|
/* ...and set the clock. */ |
|
v3020_set_reg(chip, V3020_CMD_RAM2CLOCK, 0); |
|
|
|
/* Compulab used this delay here. I dont know why, |
|
* the datasheet does not specify a delay. */ |
|
/*mdelay(5);*/ |
|
|
|
return 0; |
|
} |
|
|
|
static const struct rtc_class_ops v3020_rtc_ops = { |
|
.read_time = v3020_read_time, |
|
.set_time = v3020_set_time, |
|
}; |
|
|
|
static int rtc_probe(struct platform_device *pdev) |
|
{ |
|
struct v3020_platform_data *pdata = dev_get_platdata(&pdev->dev); |
|
struct v3020 *chip; |
|
int retval; |
|
int i; |
|
|
|
chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); |
|
if (!chip) |
|
return -ENOMEM; |
|
|
|
if (pdata->use_gpio) |
|
chip->ops = &v3020_gpio_ops; |
|
else |
|
chip->ops = &v3020_mmio_ops; |
|
|
|
retval = chip->ops->map_io(chip, pdev, pdata); |
|
if (retval) |
|
return retval; |
|
|
|
/* Make sure the v3020 expects a communication cycle |
|
* by reading 8 times */ |
|
for (i = 0; i < 8; i++) |
|
chip->ops->read_bit(chip); |
|
|
|
/* Test chip by doing a write/read sequence |
|
* to the chip ram */ |
|
v3020_set_reg(chip, V3020_SECONDS, 0x33); |
|
if (v3020_get_reg(chip, V3020_SECONDS) != 0x33) { |
|
retval = -ENODEV; |
|
goto err_io; |
|
} |
|
|
|
/* Make sure frequency measurement mode, test modes, and lock |
|
* are all disabled */ |
|
v3020_set_reg(chip, V3020_STATUS_0, 0x0); |
|
|
|
if (pdata->use_gpio) |
|
dev_info(&pdev->dev, "Chip available at GPIOs " |
|
"%d, %d, %d, %d\n", |
|
chip->gpio[V3020_CS].gpio, chip->gpio[V3020_WR].gpio, |
|
chip->gpio[V3020_RD].gpio, chip->gpio[V3020_IO].gpio); |
|
else |
|
dev_info(&pdev->dev, "Chip available at " |
|
"physical address 0x%llx," |
|
"data connected to D%d\n", |
|
(unsigned long long)pdev->resource[0].start, |
|
chip->leftshift); |
|
|
|
platform_set_drvdata(pdev, chip); |
|
|
|
chip->rtc = devm_rtc_device_register(&pdev->dev, "v3020", |
|
&v3020_rtc_ops, THIS_MODULE); |
|
if (IS_ERR(chip->rtc)) { |
|
retval = PTR_ERR(chip->rtc); |
|
goto err_io; |
|
} |
|
|
|
return 0; |
|
|
|
err_io: |
|
chip->ops->unmap_io(chip); |
|
|
|
return retval; |
|
} |
|
|
|
static int rtc_remove(struct platform_device *dev) |
|
{ |
|
struct v3020 *chip = platform_get_drvdata(dev); |
|
|
|
chip->ops->unmap_io(chip); |
|
|
|
return 0; |
|
} |
|
|
|
static struct platform_driver rtc_device_driver = { |
|
.probe = rtc_probe, |
|
.remove = rtc_remove, |
|
.driver = { |
|
.name = "v3020", |
|
}, |
|
}; |
|
|
|
module_platform_driver(rtc_device_driver); |
|
|
|
MODULE_DESCRIPTION("V3020 RTC"); |
|
MODULE_AUTHOR("Raphael Assenat"); |
|
MODULE_LICENSE("GPL"); |
|
MODULE_ALIAS("platform:v3020");
|
|
|