rtc: m48t86: allow driver to manage its resources

Allow this driver to, optionally, manage it's own resources and do the
read/write operations if the platform does not provide them.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

1 files changed, 102 insertions, 51 deletions

diff --git a/drivers/rtc/rtc-m48t86.c b/drivers/rtc/rtc-m48t86.c
index 30648ea9e8e0..4dcdbd2a2408 100644
--- a/drivers/rtc/rtc-m48t86.c
+++ b/drivers/rtc/rtc-m48t86.c
@@ -18,6 +18,7 @@
 #include <linux/platform_device.h>
 #include <linux/platform_data/rtc-m48t86.h>
 #include <linux/bcd.h>
+#include <linux/io.h>
 
 #define M48T86_SEC              0x00
 #define M48T86_SECALRM          0x01
@@ -38,39 +39,72 @@
 #define M48T86_D                0x0d
 #define M48T86_D_VRT            BIT(7)
 
+struct m48t86_rtc_info {
+        void __iomem *index_reg;
+        void __iomem *data_reg;
+        struct rtc_device *rtc;
+        struct m48t86_ops *ops;
+};
+
+static unsigned char m48t86_readb(struct device *dev, unsigned long addr)
+{
+        struct m48t86_rtc_info *info = dev_get_drvdata(dev);
+        unsigned char value;
+
+        if (info->ops) {
+                value = info->ops->readbyte(addr);
+        } else {
+                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);
+
+        if (info->ops) {
+                info->ops->writebyte(value, addr);
+        } else {
+                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_B);
+        reg = m48t86_readb(dev, M48T86_B);
 
         if (reg & M48T86_B_DM) {
                 /* data (binary) mode */
-                tm->tm_sec      = ops->readbyte(M48T86_SEC);
-                tm->tm_min      = ops->readbyte(M48T86_MIN);
-                tm->tm_hour     = ops->readbyte(M48T86_HOUR) & 0x3f;
-                tm->tm_mday     = ops->readbyte(M48T86_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_MONTH) - 1;
-                tm->tm_year     = ops->readbyte(M48T86_YEAR) + 100;
-                tm->tm_wday     = ops->readbyte(M48T86_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_SEC));
-                tm->tm_min      = bcd2bin(ops->readbyte(M48T86_MIN));
-                tm->tm_hour     = bcd2bin(ops->readbyte(M48T86_HOUR) & 0x3f);
-                tm->tm_mday     = bcd2bin(ops->readbyte(M48T86_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_MONTH)) - 1;
-                tm->tm_year     = bcd2bin(ops->readbyte(M48T86_YEAR)) + 100;
-                tm->tm_wday     = bcd2bin(ops->readbyte(M48T86_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_B_H24))
-                if (ops->readbyte(M48T86_HOUR) & 0x80)
+                if (m48t86_readb(dev, M48T86_HOUR) & 0x80)
                         tm->tm_hour += 12;
 
         return rtc_valid_tm(tm);
@@ -79,38 +113,36 @@ 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 = dev_get_platdata(&pdev->dev);
 
-        reg = ops->readbyte(M48T86_B);
+        reg = m48t86_readb(dev, M48T86_B);
 
         /* update flag and 24h mode */
         reg |= M48T86_B_SET | M48T86_B_H24;
-        ops->writebyte(reg, M48T86_B);
+        m48t86_writeb(dev, reg, M48T86_B);
 
         if (reg & M48T86_B_DM) {
                 /* data (binary) mode */
-                ops->writebyte(tm->tm_sec, M48T86_SEC);
-                ops->writebyte(tm->tm_min, M48T86_MIN);
-                ops->writebyte(tm->tm_hour, M48T86_HOUR);
-                ops->writebyte(tm->tm_mday, M48T86_DOM);
-                ops->writebyte(tm->tm_mon + 1, M48T86_MONTH);
-                ops->writebyte(tm->tm_year % 100, M48T86_YEAR);
-                ops->writebyte(tm->tm_wday, M48T86_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_SEC);
-                ops->writebyte(bin2bcd(tm->tm_min), M48T86_MIN);
-                ops->writebyte(bin2bcd(tm->tm_hour), M48T86_HOUR);
-                ops->writebyte(bin2bcd(tm->tm_mday), M48T86_DOM);
-                ops->writebyte(bin2bcd(tm->tm_mon + 1), M48T86_MONTH);
-                ops->writebyte(bin2bcd(tm->tm_year % 100), M48T86_YEAR);
-                ops->writebyte(bin2bcd(tm->tm_wday), M48T86_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_B_SET;
-        ops->writebyte(reg, M48T86_B);
+        m48t86_writeb(dev, reg, M48T86_B);
 
         return 0;
 }
@@ -118,15 +150,13 @@ 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 = dev_get_platdata(&pdev->dev);
 
-        reg = ops->readbyte(M48T86_B);
+        reg = m48t86_readb(dev, M48T86_B);
 
         seq_printf(seq, "mode\t\t: %s\n",
                    (reg & M48T86_B_DM) ? "binary" : "bcd");
 
-        reg = ops->readbyte(M48T86_D);
+        reg = m48t86_readb(dev, M48T86_D);
 
         seq_printf(seq, "battery\t\t: %s\n",
                    (reg & M48T86_D_VRT) ? "ok" : "exhausted");
@@ -140,23 +170,44 @@ 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)
 {
+        struct m48t86_rtc_info *info;
         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;
+
+        info->ops = dev_get_platdata(&pdev->dev);
+        if (!info->ops) {
+                struct resource *res;
+
+                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);
 
-        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_D);
-        dev_info(&dev->dev, "battery %s\n",
+        reg = m48t86_readb(&pdev->dev, M48T86_D);
+        dev_info(&pdev->dev, "battery %s\n",
                  (reg & M48T86_D_VRT) ? "ok" : "exhausted");
 
         return 0;