[PATCH v2 09/20] rtc: omap: add device abstraction

From: Johan Hovold
Date: Tue Oct 21 2014 - 13:45:40 EST

Add struct omap_rtc to hold previously global data as well as the
IP-block feature flags.

Also convert the register-access macros to proper inline helper functions.

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
drivers/rtc/rtc-omap.c | 239 +++++++++++++++++++++++++++----------------------
1 file changed, 133 insertions(+), 106 deletions(-)

diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index bdee29674589..1da610b8981f 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -118,26 +118,42 @@
*/
#define OMAP_RTC_HAS_32KCLK_EN BIT(2)

-static void __iomem *rtc_base;
+struct omap_rtc {
+ struct rtc_device *rtc;
+ void __iomem *base;
+ int irq_alarm;
+ int irq_timer;
+ u8 interrupts_reg;
+ unsigned long flags;
+};

-#define rtc_read(addr) readb(rtc_base + (addr))
-#define rtc_write(val, addr) writeb(val, rtc_base + (addr))
+static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)
+{
+ return readb(rtc->base + reg);
+}

-#define rtc_writel(val, addr) writel(val, rtc_base + (addr))
+static inline void rtc_write(struct omap_rtc *rtc, unsigned int reg, u8 val)
+{
+ writeb(val, rtc->base + reg);
+}

+static inline void rtc_writel(struct omap_rtc *rtc, unsigned int reg, u32 val)
+{
+ writel(val, rtc->base + reg);
+}

/* we rely on the rtc framework to handle locking (rtc->ops_lock),
* so the only other requirement is that register accesses which
* require BUSY to be clear are made with IRQs locally disabled
*/
-static void rtc_wait_not_busy(void)
+static void rtc_wait_not_busy(struct omap_rtc *rtc)
{
int count = 0;
u8 status;

/* BUSY may stay active for 1/32768 second (~30 usec) */
for (count = 0; count < 50; count++) {
- status = rtc_read(OMAP_RTC_STATUS_REG);
+ status = rtc_read(rtc, OMAP_RTC_STATUS_REG);
if ((status & (u8)OMAP_RTC_STATUS_BUSY) == 0)
break;
udelay(1);
@@ -145,16 +161,17 @@ static void rtc_wait_not_busy(void)
/* now we have ~15 usec to read/write various registers */
}

-static irqreturn_t rtc_irq(int irq, void *rtc)
+static irqreturn_t rtc_irq(int irq, void *dev_id)
{
+ struct omap_rtc *rtc = dev_id;
unsigned long events = 0;
u8 irq_data;

- irq_data = rtc_read(OMAP_RTC_STATUS_REG);
+ irq_data = rtc_read(rtc, OMAP_RTC_STATUS_REG);

/* alarm irq? */
if (irq_data & OMAP_RTC_STATUS_ALARM) {
- rtc_write(OMAP_RTC_STATUS_ALARM, OMAP_RTC_STATUS_REG);
+ rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);
events |= RTC_IRQF | RTC_AF;
}

@@ -162,23 +179,21 @@ static irqreturn_t rtc_irq(int irq, void *rtc)
if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
events |= RTC_IRQF | RTC_UF;

- rtc_update_irq(rtc, 1, events);
+ rtc_update_irq(rtc->rtc, 1, events);

return IRQ_HANDLED;
}

static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
u8 reg, irqwake_reg = 0;
- struct platform_device *pdev = to_platform_device(dev);
- const struct platform_device_id *id_entry =
- platform_get_device_id(pdev);

local_irq_disable();
- rtc_wait_not_busy();
- reg = rtc_read(OMAP_RTC_INTERRUPTS_REG);
- if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
- irqwake_reg = rtc_read(OMAP_RTC_IRQWAKEEN);
+ rtc_wait_not_busy(rtc);
+ reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ if (rtc->flags & OMAP_RTC_HAS_IRQWAKEEN)
+ irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);

if (enabled) {
reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
@@ -187,10 +202,10 @@ static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
}
- rtc_wait_not_busy();
- rtc_write(reg, OMAP_RTC_INTERRUPTS_REG);
- if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
- rtc_write(irqwake_reg, OMAP_RTC_IRQWAKEEN);
+ rtc_wait_not_busy(rtc);
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
+ if (rtc->flags & OMAP_RTC_HAS_IRQWAKEEN)
+ rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);
local_irq_enable();

return 0;
@@ -231,16 +246,18 @@ static void bcd2tm(struct rtc_time *tm)

static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
/* we don't report wday/yday/isdst ... */
local_irq_disable();
- rtc_wait_not_busy();
+ rtc_wait_not_busy(rtc);

- tm->tm_sec = rtc_read(OMAP_RTC_SECONDS_REG);
- tm->tm_min = rtc_read(OMAP_RTC_MINUTES_REG);
- tm->tm_hour = rtc_read(OMAP_RTC_HOURS_REG);
- tm->tm_mday = rtc_read(OMAP_RTC_DAYS_REG);
- tm->tm_mon = rtc_read(OMAP_RTC_MONTHS_REG);
- tm->tm_year = rtc_read(OMAP_RTC_YEARS_REG);
+ tm->tm_sec = rtc_read(rtc, OMAP_RTC_SECONDS_REG);
+ tm->tm_min = rtc_read(rtc, OMAP_RTC_MINUTES_REG);
+ tm->tm_hour = rtc_read(rtc, OMAP_RTC_HOURS_REG);
+ tm->tm_mday = rtc_read(rtc, OMAP_RTC_DAYS_REG);
+ tm->tm_mon = rtc_read(rtc, OMAP_RTC_MONTHS_REG);
+ tm->tm_year = rtc_read(rtc, OMAP_RTC_YEARS_REG);

local_irq_enable();

@@ -250,17 +267,19 @@ static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)

static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
if (tm2bcd(tm) < 0)
return -EINVAL;
local_irq_disable();
- rtc_wait_not_busy();
+ rtc_wait_not_busy(rtc);

- rtc_write(tm->tm_year, OMAP_RTC_YEARS_REG);
- rtc_write(tm->tm_mon, OMAP_RTC_MONTHS_REG);
- rtc_write(tm->tm_mday, OMAP_RTC_DAYS_REG);
- rtc_write(tm->tm_hour, OMAP_RTC_HOURS_REG);
- rtc_write(tm->tm_min, OMAP_RTC_MINUTES_REG);
- rtc_write(tm->tm_sec, OMAP_RTC_SECONDS_REG);
+ rtc_write(rtc, OMAP_RTC_YEARS_REG, tm->tm_year);
+ rtc_write(rtc, OMAP_RTC_MONTHS_REG, tm->tm_mon);
+ rtc_write(rtc, OMAP_RTC_DAYS_REG, tm->tm_mday);
+ rtc_write(rtc, OMAP_RTC_HOURS_REG, tm->tm_hour);
+ rtc_write(rtc, OMAP_RTC_MINUTES_REG, tm->tm_min);
+ rtc_write(rtc, OMAP_RTC_SECONDS_REG, tm->tm_sec);

local_irq_enable();

@@ -269,20 +288,22 @@ static int omap_rtc_set_time(struct device *dev, struct rtc_time *tm)

static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
local_irq_disable();
- rtc_wait_not_busy();
+ rtc_wait_not_busy(rtc);

- alm->time.tm_sec = rtc_read(OMAP_RTC_ALARM_SECONDS_REG);
- alm->time.tm_min = rtc_read(OMAP_RTC_ALARM_MINUTES_REG);
- alm->time.tm_hour = rtc_read(OMAP_RTC_ALARM_HOURS_REG);
- alm->time.tm_mday = rtc_read(OMAP_RTC_ALARM_DAYS_REG);
- alm->time.tm_mon = rtc_read(OMAP_RTC_ALARM_MONTHS_REG);
- alm->time.tm_year = rtc_read(OMAP_RTC_ALARM_YEARS_REG);
+ alm->time.tm_sec = rtc_read(rtc, OMAP_RTC_ALARM_SECONDS_REG);
+ alm->time.tm_min = rtc_read(rtc, OMAP_RTC_ALARM_MINUTES_REG);
+ alm->time.tm_hour = rtc_read(rtc, OMAP_RTC_ALARM_HOURS_REG);
+ alm->time.tm_mday = rtc_read(rtc, OMAP_RTC_ALARM_DAYS_REG);
+ alm->time.tm_mon = rtc_read(rtc, OMAP_RTC_ALARM_MONTHS_REG);
+ alm->time.tm_year = rtc_read(rtc, OMAP_RTC_ALARM_YEARS_REG);

local_irq_enable();

bcd2tm(&alm->time);
- alm->enabled = !!(rtc_read(OMAP_RTC_INTERRUPTS_REG)
+ alm->enabled = !!(rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG)
& OMAP_RTC_INTERRUPTS_IT_ALARM);

return 0;
@@ -290,27 +311,25 @@ static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)

static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
u8 reg, irqwake_reg = 0;
- struct platform_device *pdev = to_platform_device(dev);
- const struct platform_device_id *id_entry =
- platform_get_device_id(pdev);

if (tm2bcd(&alm->time) < 0)
return -EINVAL;

local_irq_disable();
- rtc_wait_not_busy();
+ rtc_wait_not_busy(rtc);

- rtc_write(alm->time.tm_year, OMAP_RTC_ALARM_YEARS_REG);
- rtc_write(alm->time.tm_mon, OMAP_RTC_ALARM_MONTHS_REG);
- rtc_write(alm->time.tm_mday, OMAP_RTC_ALARM_DAYS_REG);
- rtc_write(alm->time.tm_hour, OMAP_RTC_ALARM_HOURS_REG);
- rtc_write(alm->time.tm_min, OMAP_RTC_ALARM_MINUTES_REG);
- rtc_write(alm->time.tm_sec, OMAP_RTC_ALARM_SECONDS_REG);
+ rtc_write(rtc, OMAP_RTC_ALARM_YEARS_REG, alm->time.tm_year);
+ rtc_write(rtc, OMAP_RTC_ALARM_MONTHS_REG, alm->time.tm_mon);
+ rtc_write(rtc, OMAP_RTC_ALARM_DAYS_REG, alm->time.tm_mday);
+ rtc_write(rtc, OMAP_RTC_ALARM_HOURS_REG, alm->time.tm_hour);
+ rtc_write(rtc, OMAP_RTC_ALARM_MINUTES_REG, alm->time.tm_min);
+ rtc_write(rtc, OMAP_RTC_ALARM_SECONDS_REG, alm->time.tm_sec);

- reg = rtc_read(OMAP_RTC_INTERRUPTS_REG);
- if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
- irqwake_reg = rtc_read(OMAP_RTC_IRQWAKEEN);
+ reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);
+ if (rtc->flags & OMAP_RTC_HAS_IRQWAKEEN)
+ irqwake_reg = rtc_read(rtc, OMAP_RTC_IRQWAKEEN);

if (alm->enabled) {
reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
@@ -319,9 +338,9 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
}
- rtc_write(reg, OMAP_RTC_INTERRUPTS_REG);
- if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
- rtc_write(irqwake_reg, OMAP_RTC_IRQWAKEEN);
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, reg);
+ if (rtc->flags & OMAP_RTC_HAS_IRQWAKEEN)
+ rtc_write(rtc, OMAP_RTC_IRQWAKEEN, irqwake_reg);

local_irq_enable();

@@ -336,9 +355,6 @@ static struct rtc_class_ops omap_rtc_ops = {
.alarm_irq_enable = omap_rtc_alarm_irq_enable,
};

-static int omap_rtc_alarm;
-static int omap_rtc_timer;
-
#define OMAP_RTC_DATA_AM3352_IDX 1
#define OMAP_RTC_DATA_DA830_IDX 2

@@ -372,13 +388,17 @@ MODULE_DEVICE_TABLE(of, omap_rtc_of_match);

static int __init omap_rtc_probe(struct platform_device *pdev)
{
+ struct omap_rtc *rtc;
struct resource *res;
- struct rtc_device *rtc;
u8 reg, new_ctrl;
const struct platform_device_id *id_entry;
const struct of_device_id *of_id;
int ret;

+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
if (of_id)
pdev->id_entry = of_id->data;
@@ -389,26 +409,30 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
return -ENODEV;
}

- omap_rtc_timer = platform_get_irq(pdev, 0);
- if (omap_rtc_timer <= 0)
+ rtc->flags = id_entry->driver_data;
+
+ rtc->irq_timer = platform_get_irq(pdev, 0);
+ if (rtc->irq_timer <= 0)
return -ENOENT;

- omap_rtc_alarm = platform_get_irq(pdev, 1);
- if (omap_rtc_alarm <= 0)
+ rtc->irq_alarm = platform_get_irq(pdev, 1);
+ if (rtc->irq_alarm <= 0)
return -ENOENT;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- rtc_base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(rtc_base))
- return PTR_ERR(rtc_base);
+ rtc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(rtc->base))
+ return PTR_ERR(rtc->base);
+
+ platform_set_drvdata(pdev, rtc);

/* Enable the clock/module so that we can access the registers */
pm_runtime_enable(&pdev->dev);
pm_runtime_get_sync(&pdev->dev);

- if (id_entry->driver_data & OMAP_RTC_HAS_KICKER) {
- rtc_writel(KICK0_VALUE, OMAP_RTC_KICK0_REG);
- rtc_writel(KICK1_VALUE, OMAP_RTC_KICK1_REG);
+ if (rtc->flags & OMAP_RTC_HAS_KICKER) {
+ rtc_writel(rtc, OMAP_RTC_KICK0_REG, KICK0_VALUE);
+ rtc_writel(rtc, OMAP_RTC_KICK1_REG, KICK1_VALUE);
}

/*
@@ -416,25 +440,26 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
*
* NOTE: ALARM2 is not cleared on AM3352 if rtc_write (writeb) is used
*/
- rtc_writel(0, OMAP_RTC_INTERRUPTS_REG);
+ rtc_writel(rtc, OMAP_RTC_INTERRUPTS_REG, 0);

/* enable RTC functional clock */
- if (id_entry->driver_data & OMAP_RTC_HAS_32KCLK_EN) {
- reg = rtc_read(OMAP_RTC_OSC_REG);
- rtc_writel(reg | OMAP_RTC_OSC_32KCLK_EN, OMAP_RTC_OSC_REG);
+ if (rtc->flags & OMAP_RTC_HAS_32KCLK_EN) {
+ reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
+ rtc_writel(rtc, OMAP_RTC_OSC_REG,
+ reg | OMAP_RTC_OSC_32KCLK_EN);
}

/* clear old status */
- reg = rtc_read(OMAP_RTC_STATUS_REG);
+ reg = rtc_read(rtc, OMAP_RTC_STATUS_REG);
if (reg & (u8) OMAP_RTC_STATUS_POWER_UP) {
dev_info(&pdev->dev, "RTC power up reset detected\n");
- rtc_write(OMAP_RTC_STATUS_POWER_UP, OMAP_RTC_STATUS_REG);
+ rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_POWER_UP);
}
if (reg & (u8) OMAP_RTC_STATUS_ALARM)
- rtc_write(OMAP_RTC_STATUS_ALARM, OMAP_RTC_STATUS_REG);
+ rtc_write(rtc, OMAP_RTC_STATUS_REG, OMAP_RTC_STATUS_ALARM);

/* On boards with split power, RTC_ON_NOFF won't reset the RTC */
- reg = rtc_read(OMAP_RTC_CTRL_REG);
+ reg = rtc_read(rtc, OMAP_RTC_CTRL_REG);
if (reg & (u8) OMAP_RTC_CTRL_STOP)
dev_info(&pdev->dev, "already running\n");

@@ -460,27 +485,26 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "split power mode\n");

if (reg != new_ctrl)
- rtc_write(new_ctrl, OMAP_RTC_CTRL_REG);
+ rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);

device_init_wakeup(&pdev->dev, true);

- rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+ rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
&omap_rtc_ops, THIS_MODULE);
- if (IS_ERR(rtc)) {
- ret = PTR_ERR(rtc);
+ if (IS_ERR(rtc->rtc)) {
+ ret = PTR_ERR(rtc->rtc);
goto err;
}
- platform_set_drvdata(pdev, rtc);

/* handle periodic and alarm irqs */
- ret = devm_request_irq(&pdev->dev, omap_rtc_timer, rtc_irq, 0,
- dev_name(&rtc->dev), rtc);
+ ret = devm_request_irq(&pdev->dev, rtc->irq_timer, rtc_irq, 0,
+ dev_name(&rtc->rtc->dev), rtc);
if (ret)
goto err;

- if (omap_rtc_timer != omap_rtc_alarm) {
- ret = devm_request_irq(&pdev->dev, omap_rtc_alarm, rtc_irq, 0,
- dev_name(&rtc->dev), rtc);
+ if (rtc->irq_timer != rtc->irq_alarm) {
+ ret = devm_request_irq(&pdev->dev, rtc->irq_alarm, rtc_irq, 0,
+ dev_name(&rtc->rtc->dev), rtc);
if (ret)
goto err;
}
@@ -489,8 +513,8 @@ static int __init omap_rtc_probe(struct platform_device *pdev)

err:
device_init_wakeup(&pdev->dev, false);
- if (id_entry->driver_data & OMAP_RTC_HAS_KICKER)
- rtc_writel(0, OMAP_RTC_KICK0_REG);
+ if (rtc->flags & OMAP_RTC_HAS_KICKER)
+ rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);

@@ -499,16 +523,15 @@ err:

static int __exit omap_rtc_remove(struct platform_device *pdev)
{
- const struct platform_device_id *id_entry =
- platform_get_device_id(pdev);
+ struct omap_rtc *rtc = platform_get_drvdata(pdev);

device_init_wakeup(&pdev->dev, 0);

/* leave rtc running, but disable irqs */
- rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);

- if (id_entry->driver_data & OMAP_RTC_HAS_KICKER)
- rtc_writel(0, OMAP_RTC_KICK0_REG);
+ if (rtc->flags & OMAP_RTC_HAS_KICKER)
+ rtc_writel(rtc, OMAP_RTC_KICK0_REG, 0);

/* Disable the clock/module */
pm_runtime_put_sync(&pdev->dev);
@@ -518,20 +541,20 @@ static int __exit omap_rtc_remove(struct platform_device *pdev)
}

#ifdef CONFIG_PM_SLEEP
-static u8 irqstat;
-
static int omap_rtc_suspend(struct device *dev)
{
- irqstat = rtc_read(OMAP_RTC_INTERRUPTS_REG);
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
+ rtc->interrupts_reg = rtc_read(rtc, OMAP_RTC_INTERRUPTS_REG);

/* FIXME the RTC alarm is not currently acting as a wakeup event
* source on some platforms, and in fact this enable() call is just
* saving a flag that's never used...
*/
if (device_may_wakeup(dev))
- enable_irq_wake(omap_rtc_alarm);
+ enable_irq_wake(rtc->irq_alarm);
else
- rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);

/* Disable the clock/module */
pm_runtime_put_sync(dev);
@@ -541,13 +564,15 @@ static int omap_rtc_suspend(struct device *dev)

static int omap_rtc_resume(struct device *dev)
{
+ struct omap_rtc *rtc = dev_get_drvdata(dev);
+
/* Enable the clock/module so that we can access the registers */
pm_runtime_get_sync(dev);

if (device_may_wakeup(dev))
- disable_irq_wake(omap_rtc_alarm);
+ disable_irq_wake(rtc->irq_alarm);
else
- rtc_write(irqstat, OMAP_RTC_INTERRUPTS_REG);
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, rtc->interrupts_reg);

return 0;
}
@@ -557,7 +582,9 @@ static SIMPLE_DEV_PM_OPS(omap_rtc_pm_ops, omap_rtc_suspend, omap_rtc_resume);

static void omap_rtc_shutdown(struct platform_device *pdev)
{
- rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
+ struct omap_rtc *rtc = platform_get_drvdata(pdev);
+
+ rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
}

MODULE_ALIAS("platform:omap_rtc");
--
2.0.4

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