/* drivers/rtc/rtc-v3020.c * * Copyright (C) 2006 8D Technologies inc. * Copyright (C) 2004 Compulab Ltd. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * 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/rtc-v3020.h> #include <linux/delay.h> #include <asm/io.h> #undef DEBUG struct v3020 { void __iomem *ioaddress; int leftshift; struct rtc_device *rtc; }; 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++) { writel((tmp & 1) << chip->leftshift, chip->ioaddress); tmp >>= 1; udelay(1); } /* Commands dont have data */ if (!V3020_IS_COMMAND(address)) { for (i = 0; i < 8; i++) { writel((data & 1) << chip->leftshift, chip->ioaddress); 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++) { writel((address & 1) << chip->leftshift, chip->ioaddress); address >>= 1; udelay(1); } for (i = 0; i < 8; i++) { data >>= 1; if (readl(chip->ioaddress) & (1 << chip->leftshift)) 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; #ifdef DEBUG printk("\n%s : Read RTC values\n",__FUNCTION__); printk("tm_hour: %i\n",dt->tm_hour); printk("tm_min : %i\n",dt->tm_min); printk("tm_sec : %i\n",dt->tm_sec); printk("tm_year: %i\n",dt->tm_year); printk("tm_mon : %i\n",dt->tm_mon); printk("tm_mday: %i\n",dt->tm_mday); printk("tm_wday: %i\n",dt->tm_wday); #endif return 0; } static int v3020_set_time(struct device *dev, struct rtc_time *dt) { struct v3020 *chip = dev_get_drvdata(dev); #ifdef DEBUG printk("\n%s : Setting RTC values\n",__FUNCTION__); printk("tm_sec : %i\n",dt->tm_sec); printk("tm_min : %i\n",dt->tm_min); printk("tm_hour: %i\n",dt->tm_hour); printk("tm_mday: %i\n",dt->tm_mday); printk("tm_wday: %i\n",dt->tm_wday); printk("tm_year: %i\n",dt->tm_year); #endif /* 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 = pdev->dev.platform_data; struct v3020 *chip; struct rtc_device *rtc; int retval = -EBUSY; int i; int temp; if (pdev->num_resources != 1) return -EBUSY; if (pdev->resource[0].flags != IORESOURCE_MEM) return -EBUSY; chip = kzalloc(sizeof *chip, GFP_KERNEL); if (!chip) return -ENOMEM; chip->leftshift = pdata->leftshift; chip->ioaddress = ioremap(pdev->resource[0].start, 1); if (chip->ioaddress == NULL) goto err_chip; /* Make sure the v3020 expects a communication cycle * by reading 8 times */ for (i = 0; i < 8; i++) temp = readl(chip->ioaddress); /* 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 measurment mode, test modes, and lock * are all disabled */ v3020_set_reg(chip, V3020_STATUS_0, 0x0); 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); rtc = rtc_device_register("v3020", &pdev->dev, &v3020_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) { retval = PTR_ERR(rtc); goto err_io; } chip->rtc = rtc; return 0; err_io: iounmap(chip->ioaddress); err_chip: kfree(chip); return retval; } static int rtc_remove(struct platform_device *dev) { struct v3020 *chip = platform_get_drvdata(dev); struct rtc_device *rtc = chip->rtc; if (rtc) rtc_device_unregister(rtc); iounmap(chip->ioaddress); kfree(chip); return 0; } static struct platform_driver rtc_device_driver = { .probe = rtc_probe, .remove = rtc_remove, .driver = { .name = "v3020", .owner = THIS_MODULE, }, }; static __init int v3020_init(void) { return platform_driver_register(&rtc_device_driver); } static __exit void v3020_exit(void) { platform_driver_unregister(&rtc_device_driver); } module_init(v3020_init); module_exit(v3020_exit); MODULE_DESCRIPTION("V3020 RTC"); MODULE_AUTHOR("Raphael Assenat"); MODULE_LICENSE("GPL");