#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/platform_device.h>
-#include <linux/platform_data/rtc-m48t86.h>
#include <linux/bcd.h>
+#include <linux/io.h>
-#define M48T86_REG_SEC 0x00
-#define M48T86_REG_SECALRM 0x01
-#define M48T86_REG_MIN 0x02
-#define M48T86_REG_MINALRM 0x03
-#define M48T86_REG_HOUR 0x04
-#define M48T86_REG_HOURALRM 0x05
-#define M48T86_REG_DOW 0x06 /* 1 = sunday */
-#define M48T86_REG_DOM 0x07
-#define M48T86_REG_MONTH 0x08 /* 1 - 12 */
-#define M48T86_REG_YEAR 0x09 /* 0 - 99 */
-#define M48T86_REG_A 0x0A
-#define M48T86_REG_B 0x0B
-#define M48T86_REG_C 0x0C
-#define M48T86_REG_D 0x0D
-
-#define M48T86_REG_B_H24 (1 << 1)
-#define M48T86_REG_B_DM (1 << 2)
-#define M48T86_REG_B_SET (1 << 7)
-#define M48T86_REG_D_VRT (1 << 7)
+#define M48T86_SEC 0x00
+#define M48T86_SECALRM 0x01
+#define M48T86_MIN 0x02
+#define M48T86_MINALRM 0x03
+#define M48T86_HOUR 0x04
+#define M48T86_HOURALRM 0x05
+#define M48T86_DOW 0x06 /* 1 = sunday */
+#define M48T86_DOM 0x07
+#define M48T86_MONTH 0x08 /* 1 - 12 */
+#define M48T86_YEAR 0x09 /* 0 - 99 */
+#define M48T86_A 0x0a
+#define M48T86_B 0x0b
+#define M48T86_B_SET BIT(7)
+#define M48T86_B_DM BIT(2)
+#define M48T86_B_H24 BIT(1)
+#define M48T86_C 0x0c
+#define M48T86_D 0x0d
+#define M48T86_D_VRT BIT(7)
+#define M48T86_NVRAM(x) (0x0e + (x))
+#define M48T86_NVRAM_LEN 114
+
+struct m48t86_rtc_info {
+ void __iomem *index_reg;
+ void __iomem *data_reg;
+ struct rtc_device *rtc;
+};
+
+static unsigned char m48t86_readb(struct device *dev, unsigned long addr)
+{
+ struct m48t86_rtc_info *info = dev_get_drvdata(dev);
+ unsigned char value;
+
+ writeb(addr, info->index_reg);
+ value = readb(info->data_reg);
+
+ return value;
+}
+
+static void m48t86_writeb(struct device *dev,
+ unsigned char value, unsigned long addr)
+{
+ struct m48t86_rtc_info *info = dev_get_drvdata(dev);
+
+ writeb(addr, info->index_reg);
+ writeb(value, info->data_reg);
+}
static int m48t86_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
unsigned char reg;
- struct platform_device *pdev = to_platform_device(dev);
- struct m48t86_ops *ops = dev_get_platdata(&pdev->dev);
- reg = ops->readbyte(M48T86_REG_B);
+ reg = m48t86_readb(dev, M48T86_B);
- if (reg & M48T86_REG_B_DM) {
+ if (reg & M48T86_B_DM) {
/* data (binary) mode */
- tm->tm_sec = ops->readbyte(M48T86_REG_SEC);
- tm->tm_min = ops->readbyte(M48T86_REG_MIN);
- tm->tm_hour = ops->readbyte(M48T86_REG_HOUR) & 0x3F;
- tm->tm_mday = ops->readbyte(M48T86_REG_DOM);
+ tm->tm_sec = m48t86_readb(dev, M48T86_SEC);
+ tm->tm_min = m48t86_readb(dev, M48T86_MIN);
+ tm->tm_hour = m48t86_readb(dev, M48T86_HOUR) & 0x3f;
+ tm->tm_mday = m48t86_readb(dev, M48T86_DOM);
/* tm_mon is 0-11 */
- tm->tm_mon = ops->readbyte(M48T86_REG_MONTH) - 1;
- tm->tm_year = ops->readbyte(M48T86_REG_YEAR) + 100;
- tm->tm_wday = ops->readbyte(M48T86_REG_DOW);
+ tm->tm_mon = m48t86_readb(dev, M48T86_MONTH) - 1;
+ tm->tm_year = m48t86_readb(dev, M48T86_YEAR) + 100;
+ tm->tm_wday = m48t86_readb(dev, M48T86_DOW);
} else {
/* bcd mode */
- tm->tm_sec = bcd2bin(ops->readbyte(M48T86_REG_SEC));
- tm->tm_min = bcd2bin(ops->readbyte(M48T86_REG_MIN));
- tm->tm_hour = bcd2bin(ops->readbyte(M48T86_REG_HOUR) & 0x3F);
- tm->tm_mday = bcd2bin(ops->readbyte(M48T86_REG_DOM));
+ tm->tm_sec = bcd2bin(m48t86_readb(dev, M48T86_SEC));
+ tm->tm_min = bcd2bin(m48t86_readb(dev, M48T86_MIN));
+ tm->tm_hour = bcd2bin(m48t86_readb(dev, M48T86_HOUR) &
+ 0x3f);
+ tm->tm_mday = bcd2bin(m48t86_readb(dev, M48T86_DOM));
/* tm_mon is 0-11 */
- tm->tm_mon = bcd2bin(ops->readbyte(M48T86_REG_MONTH)) - 1;
- tm->tm_year = bcd2bin(ops->readbyte(M48T86_REG_YEAR)) + 100;
- tm->tm_wday = bcd2bin(ops->readbyte(M48T86_REG_DOW));
+ tm->tm_mon = bcd2bin(m48t86_readb(dev, M48T86_MONTH)) - 1;
+ tm->tm_year = bcd2bin(m48t86_readb(dev, M48T86_YEAR)) + 100;
+ tm->tm_wday = bcd2bin(m48t86_readb(dev, M48T86_DOW));
}
/* correct the hour if the clock is in 12h mode */
- if (!(reg & M48T86_REG_B_H24))
- if (ops->readbyte(M48T86_REG_HOUR) & 0x80)
+ if (!(reg & M48T86_B_H24))
+ if (m48t86_readb(dev, M48T86_HOUR) & 0x80)
tm->tm_hour += 12;
return rtc_valid_tm(tm);
static int m48t86_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
unsigned char reg;
- struct platform_device *pdev = to_platform_device(dev);
- struct m48t86_ops *ops = dev_get_platdata(&pdev->dev);
- reg = ops->readbyte(M48T86_REG_B);
+ reg = m48t86_readb(dev, M48T86_B);
/* update flag and 24h mode */
- reg |= M48T86_REG_B_SET | M48T86_REG_B_H24;
- ops->writebyte(reg, M48T86_REG_B);
+ reg |= M48T86_B_SET | M48T86_B_H24;
+ m48t86_writeb(dev, reg, M48T86_B);
- if (reg & M48T86_REG_B_DM) {
+ if (reg & M48T86_B_DM) {
/* data (binary) mode */
- ops->writebyte(tm->tm_sec, M48T86_REG_SEC);
- ops->writebyte(tm->tm_min, M48T86_REG_MIN);
- ops->writebyte(tm->tm_hour, M48T86_REG_HOUR);
- ops->writebyte(tm->tm_mday, M48T86_REG_DOM);
- ops->writebyte(tm->tm_mon + 1, M48T86_REG_MONTH);
- ops->writebyte(tm->tm_year % 100, M48T86_REG_YEAR);
- ops->writebyte(tm->tm_wday, M48T86_REG_DOW);
+ m48t86_writeb(dev, tm->tm_sec, M48T86_SEC);
+ m48t86_writeb(dev, tm->tm_min, M48T86_MIN);
+ m48t86_writeb(dev, tm->tm_hour, M48T86_HOUR);
+ m48t86_writeb(dev, tm->tm_mday, M48T86_DOM);
+ m48t86_writeb(dev, tm->tm_mon + 1, M48T86_MONTH);
+ m48t86_writeb(dev, tm->tm_year % 100, M48T86_YEAR);
+ m48t86_writeb(dev, tm->tm_wday, M48T86_DOW);
} else {
/* bcd mode */
- ops->writebyte(bin2bcd(tm->tm_sec), M48T86_REG_SEC);
- ops->writebyte(bin2bcd(tm->tm_min), M48T86_REG_MIN);
- ops->writebyte(bin2bcd(tm->tm_hour), M48T86_REG_HOUR);
- ops->writebyte(bin2bcd(tm->tm_mday), M48T86_REG_DOM);
- ops->writebyte(bin2bcd(tm->tm_mon + 1), M48T86_REG_MONTH);
- ops->writebyte(bin2bcd(tm->tm_year % 100), M48T86_REG_YEAR);
- ops->writebyte(bin2bcd(tm->tm_wday), M48T86_REG_DOW);
+ m48t86_writeb(dev, bin2bcd(tm->tm_sec), M48T86_SEC);
+ m48t86_writeb(dev, bin2bcd(tm->tm_min), M48T86_MIN);
+ m48t86_writeb(dev, bin2bcd(tm->tm_hour), M48T86_HOUR);
+ m48t86_writeb(dev, bin2bcd(tm->tm_mday), M48T86_DOM);
+ m48t86_writeb(dev, bin2bcd(tm->tm_mon + 1), M48T86_MONTH);
+ m48t86_writeb(dev, bin2bcd(tm->tm_year % 100), M48T86_YEAR);
+ m48t86_writeb(dev, bin2bcd(tm->tm_wday), M48T86_DOW);
}
/* update ended */
- reg &= ~M48T86_REG_B_SET;
- ops->writebyte(reg, M48T86_REG_B);
+ reg &= ~M48T86_B_SET;
+ m48t86_writeb(dev, reg, M48T86_B);
return 0;
}
static int m48t86_rtc_proc(struct device *dev, struct seq_file *seq)
{
unsigned char reg;
- struct platform_device *pdev = to_platform_device(dev);
- struct m48t86_ops *ops = dev_get_platdata(&pdev->dev);
- reg = ops->readbyte(M48T86_REG_B);
+ reg = m48t86_readb(dev, M48T86_B);
seq_printf(seq, "mode\t\t: %s\n",
- (reg & M48T86_REG_B_DM) ? "binary" : "bcd");
+ (reg & M48T86_B_DM) ? "binary" : "bcd");
- reg = ops->readbyte(M48T86_REG_D);
+ reg = m48t86_readb(dev, M48T86_D);
seq_printf(seq, "battery\t\t: %s\n",
- (reg & M48T86_REG_D_VRT) ? "ok" : "exhausted");
+ (reg & M48T86_D_VRT) ? "ok" : "exhausted");
return 0;
}
.proc = m48t86_rtc_proc,
};
-static int m48t86_rtc_probe(struct platform_device *dev)
+static ssize_t m48t86_nvram_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ unsigned int i;
+
+ for (i = 0; i < count; i++)
+ buf[i] = m48t86_readb(dev, M48T86_NVRAM(off + i));
+
+ return count;
+}
+
+static ssize_t m48t86_nvram_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
{
+ struct device *dev = kobj_to_dev(kobj);
+ unsigned int i;
+
+ for (i = 0; i < count; i++)
+ m48t86_writeb(dev, buf[i], M48T86_NVRAM(off + i));
+
+ return count;
+}
+
+static BIN_ATTR(nvram, 0644, m48t86_nvram_read, m48t86_nvram_write,
+ M48T86_NVRAM_LEN);
+
+/*
+ * The RTC is an optional feature at purchase time on some Technologic Systems
+ * boards. Verify that it actually exists by checking if the last two bytes
+ * of the NVRAM can be changed.
+ *
+ * This is based on the method used in their rtc7800.c example.
+ */
+static bool m48t86_verify_chip(struct platform_device *pdev)
+{
+ unsigned int offset0 = M48T86_NVRAM(M48T86_NVRAM_LEN - 2);
+ unsigned int offset1 = M48T86_NVRAM(M48T86_NVRAM_LEN - 1);
+ unsigned char tmp0, tmp1;
+
+ tmp0 = m48t86_readb(&pdev->dev, offset0);
+ tmp1 = m48t86_readb(&pdev->dev, offset1);
+
+ m48t86_writeb(&pdev->dev, 0x00, offset0);
+ m48t86_writeb(&pdev->dev, 0x55, offset1);
+ if (m48t86_readb(&pdev->dev, offset1) == 0x55) {
+ m48t86_writeb(&pdev->dev, 0xaa, offset1);
+ if (m48t86_readb(&pdev->dev, offset1) == 0xaa &&
+ m48t86_readb(&pdev->dev, offset0) == 0x00) {
+ m48t86_writeb(&pdev->dev, tmp0, offset0);
+ m48t86_writeb(&pdev->dev, tmp1, offset1);
+
+ return true;
+ }
+ }
+ return false;
+}
+
+static int m48t86_rtc_probe(struct platform_device *pdev)
+{
+ struct m48t86_rtc_info *info;
+ struct resource *res;
unsigned char reg;
- struct m48t86_ops *ops = dev_get_platdata(&dev->dev);
- struct rtc_device *rtc;
- rtc = devm_rtc_device_register(&dev->dev, "m48t86",
- &m48t86_rtc_ops, THIS_MODULE);
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+ info->index_reg = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(info->index_reg))
+ return PTR_ERR(info->index_reg);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res)
+ return -ENODEV;
+ info->data_reg = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(info->data_reg))
+ return PTR_ERR(info->data_reg);
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
+ dev_set_drvdata(&pdev->dev, info);
+
+ if (!m48t86_verify_chip(pdev)) {
+ dev_info(&pdev->dev, "RTC not present\n");
+ return -ENODEV;
+ }
- platform_set_drvdata(dev, rtc);
+ info->rtc = devm_rtc_device_register(&pdev->dev, "m48t86",
+ &m48t86_rtc_ops, THIS_MODULE);
+ if (IS_ERR(info->rtc))
+ return PTR_ERR(info->rtc);
/* read battery status */
- reg = ops->readbyte(M48T86_REG_D);
- dev_info(&dev->dev, "battery %s\n",
- (reg & M48T86_REG_D_VRT) ? "ok" : "exhausted");
+ reg = m48t86_readb(&pdev->dev, M48T86_D);
+ dev_info(&pdev->dev, "battery %s\n",
+ (reg & M48T86_D_VRT) ? "ok" : "exhausted");
+ if (device_create_bin_file(&pdev->dev, &bin_attr_nvram))
+ dev_err(&pdev->dev, "failed to create nvram sysfs entry\n");
+
+ return 0;
+}
+
+static int m48t86_rtc_remove(struct platform_device *pdev)
+{
+ device_remove_bin_file(&pdev->dev, &bin_attr_nvram);
return 0;
}
.name = "rtc-m48t86",
},
.probe = m48t86_rtc_probe,
+ .remove = m48t86_rtc_remove,
};
module_platform_driver(m48t86_rtc_platform_driver);
projects / karo-tx-linux.git / blobdiff