[PATCH 2/6] rtc: rtc-m48t86: add hooks to support driver side memory mapping
Alexander Clouter
alex at digriz.org.uk
Mon Apr 1 19:22:41 EDT 2013
If platform_data is not defined (as before), then named memory io
ranges need to be defined ("rtc_index" and "rtc_data"). The driver
then maps those regions and uses them as the RTC index and data
addresses.
Does compile with the following warnings, I cannot see the codepath
affected myself:
----
drivers/rtc/rtc-m48t86.c: In function ‘m48t86_rtc_probe’:
drivers/rtc/rtc-m48t86.c:180: warning: ‘res_index’ may be used uninitialized in this function
drivers/rtc/rtc-m48t86.c:180: warning: ‘res_data’ may be used uninitialized in this function
----
Signed-off-by: Alexander Clouter <alex at digriz.org.uk>
---
drivers/rtc/rtc-m48t86.c | 230 ++++++++++++++++++++++++++++++++++------------
1 file changed, 173 insertions(+), 57 deletions(-)
diff --git a/drivers/rtc/rtc-m48t86.c b/drivers/rtc/rtc-m48t86.c
index 25e0116..6f99e64 100644
--- a/drivers/rtc/rtc-m48t86.c
+++ b/drivers/rtc/rtc-m48t86.c
@@ -18,6 +18,8 @@
#include <linux/platform_device.h>
#include <linux/platform_data/rtc-m48t86.h>
#include <linux/bcd.h>
+#include <linux/slab.h>
+#include <linux/io.h>
#define M48T86_REG_SEC 0x00
#define M48T86_REG_SECALRM 0x01
@@ -41,40 +43,71 @@
#define DRV_VERSION "0.1"
+struct m48t86_rtc_private_data {
+ void __iomem *io_index;
+ void __iomem *io_data;
+
+ struct rtc_device *rtc;
+ struct m48t86_ops *ops;
+};
+
+static void m48t86_rtc_writebyte(struct device *dev,
+ unsigned char value, unsigned long addr)
+{
+ struct m48t86_rtc_private_data *priv = dev_get_drvdata(dev);
+
+ if (priv->ops) {
+ priv->ops->writebyte(value, addr);
+ return;
+ }
+
+ writeb(addr, priv->io_index);
+ writeb(value, priv->io_data);
+}
+
+static unsigned char m48t86_rtc_readbyte(struct device *dev,
+ unsigned long addr)
+{
+ struct m48t86_rtc_private_data *priv = dev_get_drvdata(dev);
+
+ if (priv->ops)
+ return priv->ops->readbyte(addr);
+
+ writeb(addr, priv->io_index);
+ return readb(priv->io_data);
+}
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 = pdev->dev.platform_data;
- reg = ops->readbyte(M48T86_REG_B);
+ reg = m48t86_rtc_readbyte(dev, M48T86_REG_B);
if (reg & M48T86_REG_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_rtc_readbyte(dev, M48T86_REG_SEC);
+ tm->tm_min = m48t86_rtc_readbyte(dev, M48T86_REG_MIN);
+ tm->tm_hour = m48t86_rtc_readbyte(dev, M48T86_REG_HOUR) & 0x3F;
+ tm->tm_mday = m48t86_rtc_readbyte(dev, M48T86_REG_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_rtc_readbyte(dev, M48T86_REG_MONTH) - 1;
+ tm->tm_year = m48t86_rtc_readbyte(dev, M48T86_REG_YEAR) + 100;
+ tm->tm_wday = m48t86_rtc_readbyte(dev, M48T86_REG_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_rtc_readbyte(dev, M48T86_REG_SEC));
+ tm->tm_min = bcd2bin(m48t86_rtc_readbyte(dev, M48T86_REG_MIN));
+ tm->tm_hour = bcd2bin(m48t86_rtc_readbyte(dev, M48T86_REG_HOUR) & 0x3F);
+ tm->tm_mday = bcd2bin(m48t86_rtc_readbyte(dev, M48T86_REG_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_rtc_readbyte(dev, M48T86_REG_MONTH)) - 1;
+ tm->tm_year = bcd2bin(m48t86_rtc_readbyte(dev, M48T86_REG_YEAR)) + 100;
+ tm->tm_wday = bcd2bin(m48t86_rtc_readbyte(dev, M48T86_REG_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 (m48t86_rtc_readbyte(dev, M48T86_REG_HOUR) & 0x80)
tm->tm_hour += 12;
return rtc_valid_tm(tm);
@@ -83,38 +116,36 @@ static int m48t86_rtc_read_time(struct device *dev, struct rtc_time *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 = pdev->dev.platform_data;
- reg = ops->readbyte(M48T86_REG_B);
+ reg = m48t86_rtc_readbyte(dev, M48T86_REG_B);
/* update flag and 24h mode */
reg |= M48T86_REG_B_SET | M48T86_REG_B_H24;
- ops->writebyte(reg, M48T86_REG_B);
+ m48t86_rtc_writebyte(dev, reg, M48T86_REG_B);
if (reg & M48T86_REG_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_rtc_writebyte(dev, tm->tm_sec, M48T86_REG_SEC);
+ m48t86_rtc_writebyte(dev, tm->tm_min, M48T86_REG_MIN);
+ m48t86_rtc_writebyte(dev, tm->tm_hour, M48T86_REG_HOUR);
+ m48t86_rtc_writebyte(dev, tm->tm_mday, M48T86_REG_DOM);
+ m48t86_rtc_writebyte(dev, tm->tm_mon + 1, M48T86_REG_MONTH);
+ m48t86_rtc_writebyte(dev, tm->tm_year % 100, M48T86_REG_YEAR);
+ m48t86_rtc_writebyte(dev, tm->tm_wday, M48T86_REG_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_rtc_writebyte(dev, bin2bcd(tm->tm_sec), M48T86_REG_SEC);
+ m48t86_rtc_writebyte(dev, bin2bcd(tm->tm_min), M48T86_REG_MIN);
+ m48t86_rtc_writebyte(dev, bin2bcd(tm->tm_hour), M48T86_REG_HOUR);
+ m48t86_rtc_writebyte(dev, bin2bcd(tm->tm_mday), M48T86_REG_DOM);
+ m48t86_rtc_writebyte(dev, bin2bcd(tm->tm_mon + 1), M48T86_REG_MONTH);
+ m48t86_rtc_writebyte(dev, bin2bcd(tm->tm_year % 100), M48T86_REG_YEAR);
+ m48t86_rtc_writebyte(dev, bin2bcd(tm->tm_wday), M48T86_REG_DOW);
}
/* update ended */
reg &= ~M48T86_REG_B_SET;
- ops->writebyte(reg, M48T86_REG_B);
+ m48t86_rtc_writebyte(dev, reg, M48T86_REG_B);
return 0;
}
@@ -122,15 +153,13 @@ static int m48t86_rtc_set_time(struct device *dev, struct rtc_time *tm)
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 = pdev->dev.platform_data;
- reg = ops->readbyte(M48T86_REG_B);
+ reg = m48t86_rtc_readbyte(dev, M48T86_REG_B);
seq_printf(seq, "mode\t\t: %s\n",
(reg & M48T86_REG_B_DM) ? "binary" : "bcd");
- reg = ops->readbyte(M48T86_REG_D);
+ reg = m48t86_rtc_readbyte(dev, M48T86_REG_D);
seq_printf(seq, "battery\t\t: %s\n",
(reg & M48T86_REG_D_VRT) ? "ok" : "exhausted");
@@ -144,34 +173,121 @@ static const struct rtc_class_ops m48t86_rtc_ops = {
.proc = m48t86_rtc_proc,
};
-static int m48t86_rtc_probe(struct platform_device *dev)
+static int m48t86_rtc_probe(struct platform_device *pdev)
{
unsigned char reg;
- struct m48t86_ops *ops = dev->dev.platform_data;
- struct rtc_device *rtc = rtc_device_register("m48t86",
- &dev->dev, &m48t86_rtc_ops, THIS_MODULE);
-
- if (IS_ERR(rtc))
- return PTR_ERR(rtc);
-
- platform_set_drvdata(dev, rtc);
+ int err;
+ struct resource *res_index, *res_data;
+ struct m48t86_rtc_private_data *priv;
+
+ /* Allocate memory for the device structure (and zero it) */
+ priv = kzalloc(sizeof(struct m48t86_rtc_private_data), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, priv);
+
+ if (!pdev->dev.platform_data) {
+ res_index = platform_get_resource_byname(
+ pdev, IORESOURCE_MEM, "rtc_index");
+ if (!res_index) {
+ err = -ENXIO;
+ goto out_free;
+ }
+
+ res_data = platform_get_resource_byname(
+ pdev, IORESOURCE_MEM, "rtc_data");
+ if (!res_data) {
+ err = -ENXIO;
+ goto out_free;
+ }
+
+ if (!request_mem_region(res_index->start,
+ resource_size(res_index),
+ dev_name(&pdev->dev))) {
+ err = -EBUSY;
+ goto out_free;
+ }
+
+ if (!request_mem_region(res_data->start,
+ resource_size(res_data),
+ dev_name(&pdev->dev))) {
+ err = -EBUSY;
+ goto out_release_index;
+ }
+
+ priv->io_index = ioremap(res_index->start,
+ resource_size(res_index));
+ if (!priv->io_index) {
+ err = -EIO;
+ goto out_release_data;
+ }
+
+ priv->io_data = ioremap(res_data->start,
+ resource_size(res_data));
+ if (!priv->io_data) {
+ err = -EIO;
+ goto out_io_index;
+ }
+ } else
+ priv->ops = pdev->dev.platform_data;
+
+ priv->rtc = rtc_device_register("m48t86",
+ &pdev->dev, &m48t86_rtc_ops, THIS_MODULE);
+ if (IS_ERR(priv->rtc)) {
+ err = PTR_ERR(priv->rtc);
+ if (!pdev->dev.platform_data)
+ goto out_io_data;
+ else
+ goto out_free;
+ }
/* read battery status */
- reg = ops->readbyte(M48T86_REG_D);
- dev_info(&dev->dev, "battery %s\n",
+ reg = m48t86_rtc_readbyte(&pdev->dev, M48T86_REG_D);
+ dev_info(&pdev->dev, "battery %s\n",
(reg & M48T86_REG_D_VRT) ? "ok" : "exhausted");
return 0;
+
+out_io_data:
+ iounmap(priv->io_data);
+out_io_index:
+ iounmap(priv->io_index);
+out_release_data:
+ release_mem_region(res_data->start, resource_size(res_data));
+out_release_index:
+ release_mem_region(res_index->start, resource_size(res_index));
+out_free:
+ platform_set_drvdata(pdev, NULL);
+ kfree(priv);
+ return err;
}
-static int m48t86_rtc_remove(struct platform_device *dev)
+static int m48t86_rtc_remove(struct platform_device *pdev)
{
- struct rtc_device *rtc = platform_get_drvdata(dev);
+ struct resource *res;
+ struct m48t86_rtc_private_data *priv = platform_get_drvdata(pdev);
+
+ if (priv->rtc)
+ rtc_device_unregister(priv->rtc);
+
+ if (priv->io_data) {
+ iounmap(priv->io_data);
+ res = platform_get_resource_byname(
+ pdev, IORESOURCE_MEM, "rtc_data");
+ release_mem_region(res->start, resource_size(res));
+ }
+
+ if (priv->io_index) {
+ iounmap(priv->io_index);
+ res = platform_get_resource_byname(
+ pdev, IORESOURCE_MEM, "rtc_index");
+ release_mem_region(res->start, resource_size(res));
+ }
- if (rtc)
- rtc_device_unregister(rtc);
+ platform_set_drvdata(pdev, NULL);
- platform_set_drvdata(dev, NULL);
+ kfree(priv);
return 0;
}
--
1.7.10.4
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