rtc: pm8xxx: use regmap API for register accesses

Now that the parent mfd driver has been made to work again, and has been
reworked to create a regmap instance intended for its children to use,
rework the pm8xxx driver to use the regmap API for its register
accesses.

Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/rtc/rtc-pm8xxx.c b/drivers/rtc/rtc-pm8xxx.c
index af60ee4..cdc9dc2 100644 (file)
--- a/drivers/rtc/rtc-pm8xxx.c
+++ b/drivers/rtc/rtc-pm8xxx.c
@@ -13,11 +13,12 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/rtc.h>
+#include <linux/platform_device.h>
 #include <linux/pm.h>
+#include <linux/regmap.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
-#include <linux/mfd/pm8xxx/core.h>
 #include <linux/mfd/pm8xxx/rtc.h>
 
 
@@ -37,6 +38,7 @@
 /**
  * struct pm8xxx_rtc -  rtc driver internal structure
  * @rtc:               rtc device for this driver.
+ * @regmap:            regmap used to access RTC registers
  * @rtc_alarm_irq:     rtc alarm irq number.
  * @rtc_base:          address of rtc control register.
  * @rtc_read_base:     base address of read registers.
@@ -48,6 +50,7 @@
  */
 struct pm8xxx_rtc {
        struct rtc_device *rtc;
+       struct regmap *regmap;
        int rtc_alarm_irq;
        int rtc_base;
        int rtc_read_base;
@@ -59,44 +62,6 @@ struct pm8xxx_rtc {
 };
 
 /*
- * The RTC registers need to be read/written one byte at a time. This is a
- * hardware limitation.
- */
-static int pm8xxx_read_wrapper(struct pm8xxx_rtc *rtc_dd, u8 *rtc_val,
-                              int base, int count)
-{
-       int i, rc;
-       struct device *parent = rtc_dd->rtc_dev->parent;
-
-       for (i = 0; i < count; i++) {
-               rc = pm8xxx_readb(parent, base + i, &rtc_val[i]);
-               if (rc < 0) {
-                       dev_err(rtc_dd->rtc_dev, "PMIC read failed\n");
-                       return rc;
-               }
-       }
-
-       return 0;
-}
-
-static int pm8xxx_write_wrapper(struct pm8xxx_rtc *rtc_dd, u8 *rtc_val,
-                               int base, int count)
-{
-       int i, rc;
-       struct device *parent = rtc_dd->rtc_dev->parent;
-
-       for (i = 0; i < count; i++) {
-               rc = pm8xxx_writeb(parent, base + i, rtc_val[i]);
-               if (rc < 0) {
-                       dev_err(rtc_dd->rtc_dev, "PMIC write failed\n");
-                       return rc;
-               }
-       }
-
-       return 0;
-}
-
-/*
  * Steps to write the RTC registers.
  * 1. Disable alarm if enabled.
  * 2. Write 0x00 to LSB.
@@ -107,7 +72,7 @@ static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
        int rc, i;
        unsigned long secs, irq_flags;
-       u8 value[NUM_8_BIT_RTC_REGS], reg = 0, alarm_enabled = 0, ctrl_reg;
+       u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, ctrl_reg;
        struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
        rtc_tm_to_time(tm, &secs);
@@ -125,9 +90,8 @@ static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
        if (ctrl_reg & PM8xxx_RTC_ALARM_ENABLE) {
                alarm_enabled = 1;
                ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
-               rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base,
-                                         1);
-               if (rc < 0) {
+               rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
+               if (rc) {
                        dev_err(dev, "Write to RTC control register failed\n");
                        goto rtc_rw_fail;
                }
@@ -137,33 +101,31 @@ static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
        }
 
        /* Write 0 to Byte[0] */
-       reg = 0;
-       rc = pm8xxx_write_wrapper(rtc_dd, &reg, rtc_dd->rtc_write_base, 1);
-       if (rc < 0) {
+       rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_write_base, 0);
+       if (rc) {
                dev_err(dev, "Write to RTC write data register failed\n");
                goto rtc_rw_fail;
        }
 
        /* Write Byte[1], Byte[2], Byte[3] */
-       rc = pm8xxx_write_wrapper(rtc_dd, value + 1,
-                                 rtc_dd->rtc_write_base + 1, 3);
-       if (rc < 0) {
+       rc = regmap_bulk_write(rtc_dd->regmap, rtc_dd->rtc_write_base + 1,
+                              &value[1], sizeof(value) - 1);
+       if (rc) {
                dev_err(dev, "Write to RTC write data register failed\n");
                goto rtc_rw_fail;
        }
 
        /* Write Byte[0] */
-       rc = pm8xxx_write_wrapper(rtc_dd, value, rtc_dd->rtc_write_base, 1);
-       if (rc < 0) {
+       rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_write_base, value[0]);
+       if (rc) {
                dev_err(dev, "Write to RTC write data register failed\n");
                goto rtc_rw_fail;
        }
 
        if (alarm_enabled) {
                ctrl_reg |= PM8xxx_RTC_ALARM_ENABLE;
-               rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base,
-                                         1);
-               if (rc < 0) {
+               rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
+               if (rc) {
                        dev_err(dev, "Write to RTC control register failed\n");
                        goto rtc_rw_fail;
                }
@@ -180,13 +142,14 @@ rtc_rw_fail:
 static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
        int rc;
-       u8 value[NUM_8_BIT_RTC_REGS], reg;
+       u8 value[NUM_8_BIT_RTC_REGS];
        unsigned long secs;
+       unsigned int reg;
        struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
-       rc = pm8xxx_read_wrapper(rtc_dd, value, rtc_dd->rtc_read_base,
-                                NUM_8_BIT_RTC_REGS);
-       if (rc < 0) {
+       rc = regmap_bulk_read(rtc_dd->regmap, rtc_dd->rtc_read_base,
+                             value, sizeof(value));
+       if (rc) {
                dev_err(dev, "RTC read data register failed\n");
                return rc;
        }
@@ -195,17 +158,16 @@ static int pm8xxx_rtc_read_time(struct device *dev, struct rtc_time *tm)
         * Read the LSB again and check if there has been a carry over.
         * If there is, redo the read operation.
         */
-       rc = pm8xxx_read_wrapper(rtc_dd, &reg, rtc_dd->rtc_read_base, 1);
+       rc = regmap_read(rtc_dd->regmap, rtc_dd->rtc_read_base, &reg);
        if (rc < 0) {
                dev_err(dev, "RTC read data register failed\n");
                return rc;
        }
 
        if (unlikely(reg < value[0])) {
-               rc = pm8xxx_read_wrapper(rtc_dd, value,
-                                        rtc_dd->rtc_read_base,
-                                        NUM_8_BIT_RTC_REGS);
-               if (rc < 0) {
+               rc = regmap_bulk_read(rtc_dd->regmap, rtc_dd->rtc_read_base,
+                                     value, sizeof(value));
+               if (rc) {
                        dev_err(dev, "RTC read data register failed\n");
                        return rc;
                }
@@ -244,9 +206,9 @@ static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 
        spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
 
-       rc = pm8xxx_write_wrapper(rtc_dd, value, rtc_dd->alarm_rw_base,
-                                 NUM_8_BIT_RTC_REGS);
-       if (rc < 0) {
+       rc = regmap_bulk_write(rtc_dd->regmap, rtc_dd->alarm_rw_base, value,
+                              sizeof(value));
+       if (rc) {
                dev_err(dev, "Write to RTC ALARM register failed\n");
                goto rtc_rw_fail;
        }
@@ -258,8 +220,8 @@ static int pm8xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
        else
                ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
 
-       rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base, 1);
-       if (rc < 0) {
+       rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
+       if (rc) {
                dev_err(dev, "Write to RTC control register failed\n");
                goto rtc_rw_fail;
        }
@@ -282,9 +244,9 @@ static int pm8xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
        unsigned long secs;
        struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev);
 
-       rc = pm8xxx_read_wrapper(rtc_dd, value, rtc_dd->alarm_rw_base,
-                                NUM_8_BIT_RTC_REGS);
-       if (rc < 0) {
+       rc = regmap_bulk_read(rtc_dd->regmap, rtc_dd->alarm_rw_base, value,
+                             sizeof(value));
+       if (rc) {
                dev_err(dev, "RTC alarm time read failed\n");
                return rc;
        }
@@ -323,8 +285,8 @@ static int pm8xxx_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
        else
                ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
 
-       rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base, 1);
-       if (rc < 0) {
+       rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
+       if (rc) {
                dev_err(dev, "Write to RTC control register failed\n");
                goto rtc_rw_fail;
        }
@@ -346,7 +308,7 @@ static struct rtc_class_ops pm8xxx_rtc_ops = {
 static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
 {
        struct pm8xxx_rtc *rtc_dd = dev_id;
-       u8 ctrl_reg;
+       unsigned int ctrl_reg;
        int rc;
        unsigned long irq_flags;
 
@@ -358,8 +320,8 @@ static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
        ctrl_reg = rtc_dd->ctrl_reg;
        ctrl_reg &= ~PM8xxx_RTC_ALARM_ENABLE;
 
-       rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base, 1);
-       if (rc < 0) {
+       rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
+       if (rc) {
                spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
                dev_err(rtc_dd->rtc_dev,
                        "Write to RTC control register failed\n");
@@ -370,18 +332,20 @@ static irqreturn_t pm8xxx_alarm_trigger(int irq, void *dev_id)
        spin_unlock_irqrestore(&rtc_dd->ctrl_reg_lock, irq_flags);
 
        /* Clear RTC alarm register */
-       rc = pm8xxx_read_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base +
-                                PM8XXX_ALARM_CTRL_OFFSET, 1);
-       if (rc < 0) {
+       rc = regmap_read(rtc_dd->regmap,
+                        rtc_dd->rtc_base + PM8XXX_ALARM_CTRL_OFFSET,
+                        &ctrl_reg);
+       if (rc) {
                dev_err(rtc_dd->rtc_dev,
                        "RTC Alarm control register read failed\n");
                goto rtc_alarm_handled;
        }
 
        ctrl_reg &= ~PM8xxx_RTC_ALARM_CLEAR;
-       rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base +
-                                 PM8XXX_ALARM_CTRL_OFFSET, 1);
-       if (rc < 0)
+       rc = regmap_write(rtc_dd->regmap,
+                         rtc_dd->rtc_base + PM8XXX_ALARM_CTRL_OFFSET,
+                         ctrl_reg);
+       if (rc)
                dev_err(rtc_dd->rtc_dev,
                        "Write to RTC Alarm control register failed\n");
 
@@ -392,7 +356,7 @@ rtc_alarm_handled:
 static int pm8xxx_rtc_probe(struct platform_device *pdev)
 {
        int rc;
-       u8 ctrl_reg;
+       unsigned int ctrl_reg;
        bool rtc_write_enable = false;
        struct pm8xxx_rtc *rtc_dd;
        struct resource *rtc_resource;
@@ -409,6 +373,12 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
        /* Initialise spinlock to protect RTC control register */
        spin_lock_init(&rtc_dd->ctrl_reg_lock);
 
+       rtc_dd->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+       if (!rtc_dd->regmap) {
+               dev_err(&pdev->dev, "Parent regmap unavailable.\n");
+               return -ENXIO;
+       }
+
        rtc_dd->rtc_alarm_irq = platform_get_irq(pdev, 0);
        if (rtc_dd->rtc_alarm_irq < 0) {
                dev_err(&pdev->dev, "Alarm IRQ resource absent!\n");
@@ -432,17 +402,16 @@ static int pm8xxx_rtc_probe(struct platform_device *pdev)
        rtc_dd->rtc_dev = &pdev->dev;
 
        /* Check if the RTC is on, else turn it on */
-       rc = pm8xxx_read_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base, 1);
-       if (rc < 0) {
+       rc = regmap_read(rtc_dd->regmap, rtc_dd->rtc_base, &ctrl_reg);
+       if (rc) {
                dev_err(&pdev->dev, "RTC control register read failed!\n");
                return rc;
        }
 
        if (!(ctrl_reg & PM8xxx_RTC_ENABLE)) {
                ctrl_reg |= PM8xxx_RTC_ENABLE;
-               rc = pm8xxx_write_wrapper(rtc_dd, &ctrl_reg, rtc_dd->rtc_base,
-                                                                       1);
-               if (rc < 0) {
+               rc = regmap_write(rtc_dd->regmap, rtc_dd->rtc_base, ctrl_reg);
+               if (rc) {
                        dev_err(&pdev->dev,
                                "Write to RTC control register failed\n");
                        return rc;