2010-08-21 12:30:52

by Hiremath, Vaibhav

Subject: [PATCH-V2 3/3] RTC:s35390a: Add update_irq (per Min interrupt) support

From: Vaibhav Hiremath <[email protected]>

S35390A RTC supports per minute steady interrupt, after configuration
device steadily keeps on generating interrupts every minute. So add
related RTC API's -
- update_irq_enable

Signed-off-by: Vaibhav Hiremath <[email protected]>
---
drivers/rtc/rtc-s35390a.c | 32 ++++++++++++++++++++++++++++++++
1 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
index d8d59d7..34c9c47 100644
--- a/drivers/rtc/rtc-s35390a.c
+++ b/drivers/rtc/rtc-s35390a.c
@@ -390,6 +390,35 @@ static int s35390a_rtc_set_irq_freq(struct device *dev, int freq)
return s35390a_set_irq_freq(to_i2c_client(dev), freq);
}

+static int s35390a_update_irq_enable(struct i2c_client *client,
+ unsigned enabled)
+{
+ struct s35390a *s35390a = i2c_get_clientdata(client);
+ char buf[1];
+
+ if (s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf)) < 0)
+ return -EIO;
+
+ /* This chip returns the bits of each byte in reverse order */
+ buf[0] = bitrev8(buf[0]);
+
+ buf[0] &= ~S35390A_INT1_MODE_MASK;
+ if (enabled)
+ buf[0] |= S35390A_INT1_MODE_PMIN_STDY;
+ else
+ buf[0] |= S35390A_INT1_MODE_NOINTR;
+
+ /* This chip expects the bits of each byte in reverse order */
+ buf[0] = bitrev8(buf[0]);
+
+ return s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf));
+}
+
+static int s35390a_rtc_update_irq_enable(struct device *dev, unsigned enabled)
+{
+ return s35390a_update_irq_enable(to_i2c_client(dev), enabled);
+}
+
static irqreturn_t s35390a_irq_thread(int irq, void *handle)
{
char buf[1];
@@ -406,6 +435,8 @@ static irqreturn_t s35390a_irq_thread(int irq, void *handle)
if (buf[0] & BIT(2)) {
rtc_update_irq(s35390a->rtc, 1, RTC_IRQF | RTC_AF);
s35390a_alarm_irq_enable(client, 0);
+ } else if (buf[0] & BIT(1)) {
+ rtc_update_irq(s35390a->rtc, 1, RTC_IRQF | RTC_UF);
} else if (buf[0] & BIT(0)) {
rtc_update_irq(s35390a->rtc, 1, RTC_IRQF | RTC_PF);
}
@@ -422,6 +453,7 @@ static const struct rtc_class_ops s35390a_rtc_ops = {
.read_alarm = s35390a_rtc_read_alarm,
.irq_set_freq = s35390a_rtc_set_irq_freq,
.irq_set_state = s35390a_rtc_freq_irq_enable,
+ .update_irq_enable = s35390a_rtc_update_irq_enable,
};

static struct i2c_driver s35390a_driver;
--
1.6.2.4

2010-08-23 23:43:50

by Andrew Morton

Subject: Re: [PATCH-V2 3/3] RTC:s35390a: Add update_irq (per Min interrupt) support

On Sat, 21 Aug 2010 18:00:29 +0530
[email protected] wrote:

> +static int s35390a_update_irq_enable(struct i2c_client *client,
> + unsigned enabled)
> +{
> + struct s35390a *s35390a = i2c_get_clientdata(client);
> + char buf[1];
> +
> + if (s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf)) < 0)
> + return -EIO;
> +
> + /* This chip returns the bits of each byte in reverse order */
> + buf[0] = bitrev8(buf[0]);
> +
> + buf[0] &= ~S35390A_INT1_MODE_MASK;
> + if (enabled)
> + buf[0] |= S35390A_INT1_MODE_PMIN_STDY;
> + else
> + buf[0] |= S35390A_INT1_MODE_NOINTR;
> +
> + /* This chip expects the bits of each byte in reverse order */
> + buf[0] = bitrev8(buf[0]);

grumble. We bit-reverse it, fiddle a couple of bits and then
bit-reverse it again. Lazy.

Why not leave it bit-reversed and just bit-reverse the constants?
Extra marks are awarded for coming up with a compile-time bitrev8() ;)

> + return s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, buf, sizeof(buf));
> +}