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authorDavid S. Miller <davem@davemloft.net>2013-06-20 01:49:39 +0200
committerDavid S. Miller <davem@davemloft.net>2013-06-20 01:49:39 +0200
commitd98cae64e4a733ff377184d78aa0b1f2b54faede (patch)
treee973e3c93fe7e17741567ac3947f5197bc9d582d /drivers/rtc/rtc-at91rm9200.c
parentbcm63xx_enet: fix return value check in bcm_enet_shared_probe() (diff)
parentMerge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linvil... (diff)
downloadlinux-d98cae64e4a733ff377184d78aa0b1f2b54faede.tar.xz
linux-d98cae64e4a733ff377184d78aa0b1f2b54faede.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: drivers/net/wireless/ath/ath9k/Kconfig drivers/net/xen-netback/netback.c net/batman-adv/bat_iv_ogm.c net/wireless/nl80211.c The ath9k Kconfig conflict was a change of a Kconfig option name right next to the deletion of another option. The xen-netback conflict was overlapping changes involving the handling of the notify list in xen_netbk_rx_action(). Batman conflict resolution provided by Antonio Quartulli, basically keep everything in both conflict hunks. The nl80211 conflict is a little more involved. In 'net' we added a dynamic memory allocation to nl80211_dump_wiphy() to fix a race that Linus reported. Meanwhile in 'net-next' the handlers were converted to use pre and post doit handlers which use a flag to determine whether to hold the RTNL mutex around the operation. However, the dump handlers to not use this logic. Instead they have to explicitly do the locking. There were apparent bugs in the conversion of nl80211_dump_wiphy() in that we were not dropping the RTNL mutex in all the return paths, and it seems we very much should be doing so. So I fixed that whilst handling the overlapping changes. To simplify the initial returns, I take the RTNL mutex after we try to allocate 'tb'. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/rtc/rtc-at91rm9200.c')
-rw-r--r--drivers/rtc/rtc-at91rm9200.c131
1 files changed, 111 insertions, 20 deletions
diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c
index 0eab77b22340..f296f3f7db9b 100644
--- a/drivers/rtc/rtc-at91rm9200.c
+++ b/drivers/rtc/rtc-at91rm9200.c
@@ -25,6 +25,7 @@
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/interrupt.h>
+#include <linux/spinlock.h>
#include <linux/ioctl.h>
#include <linux/completion.h>
#include <linux/io.h>
@@ -42,10 +43,65 @@
#define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */
+struct at91_rtc_config {
+ bool use_shadow_imr;
+};
+
+static const struct at91_rtc_config *at91_rtc_config;
static DECLARE_COMPLETION(at91_rtc_updated);
static unsigned int at91_alarm_year = AT91_RTC_EPOCH;
static void __iomem *at91_rtc_regs;
static int irq;
+static DEFINE_SPINLOCK(at91_rtc_lock);
+static u32 at91_rtc_shadow_imr;
+
+static void at91_rtc_write_ier(u32 mask)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&at91_rtc_lock, flags);
+ at91_rtc_shadow_imr |= mask;
+ at91_rtc_write(AT91_RTC_IER, mask);
+ spin_unlock_irqrestore(&at91_rtc_lock, flags);
+}
+
+static void at91_rtc_write_idr(u32 mask)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&at91_rtc_lock, flags);
+ at91_rtc_write(AT91_RTC_IDR, mask);
+ /*
+ * Register read back (of any RTC-register) needed to make sure
+ * IDR-register write has reached the peripheral before updating
+ * shadow mask.
+ *
+ * Note that there is still a possibility that the mask is updated
+ * before interrupts have actually been disabled in hardware. The only
+ * way to be certain would be to poll the IMR-register, which is is
+ * the very register we are trying to emulate. The register read back
+ * is a reasonable heuristic.
+ */
+ at91_rtc_read(AT91_RTC_SR);
+ at91_rtc_shadow_imr &= ~mask;
+ spin_unlock_irqrestore(&at91_rtc_lock, flags);
+}
+
+static u32 at91_rtc_read_imr(void)
+{
+ unsigned long flags;
+ u32 mask;
+
+ if (at91_rtc_config->use_shadow_imr) {
+ spin_lock_irqsave(&at91_rtc_lock, flags);
+ mask = at91_rtc_shadow_imr;
+ spin_unlock_irqrestore(&at91_rtc_lock, flags);
+ } else {
+ mask = at91_rtc_read(AT91_RTC_IMR);
+ }
+
+ return mask;
+}
/*
* Decode time/date into rtc_time structure
@@ -110,9 +166,9 @@ static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
cr = at91_rtc_read(AT91_RTC_CR);
at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
- at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD);
+ at91_rtc_write_ier(AT91_RTC_ACKUPD);
wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
- at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD);
+ at91_rtc_write_idr(AT91_RTC_ACKUPD);
at91_rtc_write(AT91_RTC_TIMR,
bin2bcd(tm->tm_sec) << 0
@@ -144,7 +200,7 @@ static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
tm->tm_year = at91_alarm_year - 1900;
- alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
+ alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM)
? 1 : 0;
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
@@ -169,7 +225,7 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
tm.tm_min = alrm->time.tm_min;
tm.tm_sec = alrm->time.tm_sec;
- at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
+ at91_rtc_write_idr(AT91_RTC_ALARM);
at91_rtc_write(AT91_RTC_TIMALR,
bin2bcd(tm.tm_sec) << 0
| bin2bcd(tm.tm_min) << 8
@@ -182,7 +238,7 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
if (alrm->enabled) {
at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
- at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
+ at91_rtc_write_ier(AT91_RTC_ALARM);
}
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
@@ -198,9 +254,9 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
if (enabled) {
at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM);
- at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM);
+ at91_rtc_write_ier(AT91_RTC_ALARM);
} else
- at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM);
+ at91_rtc_write_idr(AT91_RTC_ALARM);
return 0;
}
@@ -209,7 +265,7 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
*/
static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
{
- unsigned long imr = at91_rtc_read(AT91_RTC_IMR);
+ unsigned long imr = at91_rtc_read_imr();
seq_printf(seq, "update_IRQ\t: %s\n",
(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
@@ -229,7 +285,7 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
unsigned int rtsr;
unsigned long events = 0;
- rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR);
+ rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
if (rtsr) { /* this interrupt is shared! Is it ours? */
if (rtsr & AT91_RTC_ALARM)
events |= (RTC_AF | RTC_IRQF);
@@ -250,6 +306,43 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
return IRQ_NONE; /* not handled */
}
+static const struct at91_rtc_config at91rm9200_config = {
+};
+
+static const struct at91_rtc_config at91sam9x5_config = {
+ .use_shadow_imr = true,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id at91_rtc_dt_ids[] = {
+ {
+ .compatible = "atmel,at91rm9200-rtc",
+ .data = &at91rm9200_config,
+ }, {
+ .compatible = "atmel,at91sam9x5-rtc",
+ .data = &at91sam9x5_config,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
+#endif
+
+static const struct at91_rtc_config *
+at91_rtc_get_config(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+
+ if (pdev->dev.of_node) {
+ match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node);
+ if (!match)
+ return NULL;
+ return (const struct at91_rtc_config *)match->data;
+ }
+
+ return &at91rm9200_config;
+}
+
static const struct rtc_class_ops at91_rtc_ops = {
.read_time = at91_rtc_readtime,
.set_time = at91_rtc_settime,
@@ -268,6 +361,10 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
struct resource *regs;
int ret = 0;
+ at91_rtc_config = at91_rtc_get_config(pdev);
+ if (!at91_rtc_config)
+ return -ENODEV;
+
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs) {
dev_err(&pdev->dev, "no mmio resource defined\n");
@@ -290,7 +387,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev)
at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */
/* Disable all interrupts */
- at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
+ at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
AT91_RTC_SECEV | AT91_RTC_TIMEV |
AT91_RTC_CALEV);
@@ -335,7 +432,7 @@ static int __exit at91_rtc_remove(struct platform_device *pdev)
struct rtc_device *rtc = platform_get_drvdata(pdev);
/* Disable all interrupts */
- at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM |
+ at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM |
AT91_RTC_SECEV | AT91_RTC_TIMEV |
AT91_RTC_CALEV);
free_irq(irq, pdev);
@@ -358,13 +455,13 @@ static int at91_rtc_suspend(struct device *dev)
/* this IRQ is shared with DBGU and other hardware which isn't
* necessarily doing PM like we are...
*/
- at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR)
+ at91_rtc_imr = at91_rtc_read_imr()
& (AT91_RTC_ALARM|AT91_RTC_SECEV);
if (at91_rtc_imr) {
if (device_may_wakeup(dev))
enable_irq_wake(irq);
else
- at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr);
+ at91_rtc_write_idr(at91_rtc_imr);
}
return 0;
}
@@ -375,7 +472,7 @@ static int at91_rtc_resume(struct device *dev)
if (device_may_wakeup(dev))
disable_irq_wake(irq);
else
- at91_rtc_write(AT91_RTC_IER, at91_rtc_imr);
+ at91_rtc_write_ier(at91_rtc_imr);
}
return 0;
}
@@ -383,12 +480,6 @@ static int at91_rtc_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume);
-static const struct of_device_id at91_rtc_dt_ids[] = {
- { .compatible = "atmel,at91rm9200-rtc" },
- { /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids);
-
static struct platform_driver at91_rtc_driver = {
.remove = __exit_p(at91_rtc_remove),
.driver = {