+++ /dev/null
-// 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 <raph@8d.com>
- * - 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");
projects / platform / kernel / linux-rpi.git / commitdiff