]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
ARM: OMAP Add RTC support to the (new style) Menelaus driver.
authorDavid Brownell <dbrownell@users.sourceforge.net>
Wed, 13 Jun 2007 14:16:29 +0000 (19:46 +0530)
committerTony Lindgren <tony@atomide.com>
Wed, 13 Jun 2007 13:25:47 +0000 (06:25 -0700)
This involved several bugfixes and cleanups to the IRQ handling logic.
Code for the second register bank never worked, and even clobbered
non-RTC registers; and the handler enabled IRQs for interrupts that
should have stayed masked...

Passes 'rtctest' on H4, other than lack of "periodic" (1/N second) IRQs.
System wakeup alarms (from suspend-to-RAM) work too.

The battery keeps the RTC active over power off, so once you set clock
(rdate/ntpdate/etc, then "hwclock -w") then RTC_HCTOSYS at boot time
will behave as expected.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
drivers/i2c/chips/menelaus.c
drivers/rtc/Kconfig

index 4ac531fcbdf90e1fa9d23ac8244418b35aa986c5..eaa4e1caba0a82b119f58aa259a7440c055115b9 100644 (file)
@@ -1,3 +1,4 @@
+#define DEBUG
 /*
  * drivers/i2c/chips/menelaus.c
  *
@@ -39,6 +40,8 @@
 #include <linux/sched.h>
 #include <linux/mutex.h>
 #include <linux/workqueue.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
 
 #include <asm/mach-types.h>
 #include <asm/mach/irq.h>
@@ -135,8 +138,14 @@ struct menelaus_chip {
        struct mutex            lock;
        struct i2c_client       *client;
        struct work_struct      work;
+#ifdef CONFIG_RTC_DRV_TWL92330
+       struct rtc_device       *rtc;
+       u8                      rtc_control;
+       unsigned                uie:1;
+#endif
        unsigned                vcore_hw_mode:1;
-       void                    *handlers[16];
+       u8                      mask1, mask2;
+       void                    (*handlers[16])(struct menelaus_chip *);
        void                    (*mmc_callback)(void *data, u8 mask);
        void                    *mmc_callback_data;
 };
@@ -167,26 +176,30 @@ static int menelaus_read_reg(int reg)
 
 static int menelaus_enable_irq(int irq)
 {
-       if (irq > 7)
+       if (irq > 7) {
+               irq -= 8;
+               the_menelaus->mask2 &= ~(1 << irq);
                return menelaus_write_reg(MENELAUS_INT_MASK2,
-                                         menelaus_read_reg(MENELAUS_INT_MASK2)
-                                         & ~(1 << (irq - 8)));
-       else
+                               the_menelaus->mask2);
+       } else {
+               the_menelaus->mask1 &= ~(1 << irq);
                return menelaus_write_reg(MENELAUS_INT_MASK1,
-                                         menelaus_read_reg(MENELAUS_INT_MASK1)
-                                         & ~(1 << irq));
+                               the_menelaus->mask1);
+       }
 }
 
 static int menelaus_disable_irq(int irq)
 {
-       if (irq > 7)
-               return menelaus_write_reg(menelaus_read_reg(MENELAUS_INT_MASK2)
-                                         | (1 << (irq - 8)),
-                                         MENELAUS_INT_MASK2);
-       else
+       if (irq > 7) {
+               irq -= 8;
+               the_menelaus->mask2 |= (1 << irq);
+               return menelaus_write_reg(MENELAUS_INT_MASK2,
+                               the_menelaus->mask2);
+       } else {
+               the_menelaus->mask1 |= (1 << irq);
                return menelaus_write_reg(MENELAUS_INT_MASK1,
-                                         menelaus_read_reg(MENELAUS_INT_MASK1)
-                                         | (1 << irq));
+                               the_menelaus->mask1);
+       }
 }
 
 static int menelaus_ack_irq(int irq)
@@ -198,7 +211,8 @@ static int menelaus_ack_irq(int irq)
 }
 
 /* Adds a handler for an interrupt. Does not run in interrupt context */
-static int menelaus_add_irq_work(int irq, void * handler)
+static int menelaus_add_irq_work(int irq,
+               void (*handler)(struct menelaus_chip *))
 {
        int ret = 0;
 
@@ -229,14 +243,14 @@ static int menelaus_remove_irq_work(int irq)
  * in each slot. In this case the cards are not seen by menelaus.
  * FIXME: Add handling for D1 too
  */
-static int menelaus_mmc_cd_work(struct menelaus_chip * menelaus_hw)
+static void menelaus_mmc_cd_work(struct menelaus_chip * menelaus_hw)
 {
        int reg;
        unsigned char card_mask = 0;
 
        reg = menelaus_read_reg(MENELAUS_MCT_PIN_ST);
        if (reg < 0)
-               return reg;
+               return;
 
        if (!(reg & 0x1))
                card_mask |= (1 << 0);
@@ -247,8 +261,6 @@ static int menelaus_mmc_cd_work(struct menelaus_chip * menelaus_hw)
        if (menelaus_hw->mmc_callback)
                menelaus_hw->mmc_callback(menelaus_hw->mmc_callback_data,
                                          card_mask);
-
-       return 0;
 }
 
 /*
@@ -759,30 +771,30 @@ static void menelaus_work(struct work_struct *_menelaus)
 {
        struct menelaus_chip *menelaus =
                        container_of(_menelaus, struct menelaus_chip, work);
-       int (*handler)(struct menelaus_chip *menelaus);
+       void (*handler)(struct menelaus_chip *menelaus);
 
        while (1) {
-               int i;
-               unsigned char isr;
-
-               isr = menelaus_read_reg(MENELAUS_INT_STATUS1) |
-                     (menelaus_read_reg(MENELAUS_INT_STATUS2) << 8);
+               unsigned isr;
 
+               isr = (menelaus_read_reg(MENELAUS_INT_STATUS2)
+                               & ~menelaus->mask2) << 8;
+               isr |= menelaus_read_reg(MENELAUS_INT_STATUS1)
+                               & ~menelaus->mask1;
                if (!isr)
                        break;
 
-               for (i = 0; i < IH_MENELAUS_IRQS; i++) {
-                       if (isr & (1 << i)) {
-                               mutex_lock(&menelaus->lock);
-                               menelaus_disable_irq(i);
-                               menelaus_ack_irq(i);
-                               if (menelaus->handlers[i]) {
-                                       handler = menelaus->handlers[i];
-                                       handler(menelaus);
-                               }
-                               menelaus_enable_irq(i);
-                               mutex_unlock(&menelaus->lock);
-                       }
+               while (isr) {
+                       int irq = fls(isr) - 1;
+                       isr &= ~(1 << irq);
+
+                       mutex_lock(&menelaus->lock);
+                       menelaus_disable_irq(irq);
+                       menelaus_ack_irq(irq);
+                       handler = menelaus->handlers[irq];
+                       if (handler)
+                               handler(menelaus);
+                       menelaus_enable_irq(irq);
+                       mutex_unlock(&menelaus->lock);
                }
        }
        enable_irq(menelaus->client->irq);
@@ -801,6 +813,344 @@ static irqreturn_t menelaus_irq(int irq, void *_menelaus)
        return IRQ_HANDLED;
 }
 
+/*-----------------------------------------------------------------------*/
+
+/*
+ * The RTC needs to be set once, then it runs on backup battery power.
+ * It supports alarms, including system wake alarms (from some modes);
+ * and 1/second IRQs if requested.
+ */
+#ifdef CONFIG_RTC_DRV_TWL92330
+
+#define RTC_CTRL_RTC_EN                (1 << 0)
+#define RTC_CTRL_AL_EN         (1 << 1)
+#define RTC_CTRL_MODE12                (1 << 2)
+#define RTC_CTRL_EVERY_MASK    (3 << 3)
+#define RTC_CTRL_EVERY_SEC     (0 << 3)
+#define RTC_CTRL_EVERY_MIN     (1 << 3)
+#define RTC_CTRL_EVERY_HR      (2 << 3)
+#define RTC_CTRL_EVERY_DAY     (3 << 3)
+
+#define RTC_UPDATE_EVERY       0x08
+
+#define RTC_HR_PM              (1 << 7)
+
+static void menelaus_to_time(char *regs, struct rtc_time *t)
+{
+       t->tm_sec = BCD2BIN(regs[0]);
+       t->tm_min = BCD2BIN(regs[1]);
+       if (the_menelaus->rtc_control & RTC_CTRL_MODE12) {
+               t->tm_hour = BCD2BIN(regs[2] & 0x1f) - 1;
+               if (regs[2] & RTC_HR_PM)
+                       t->tm_hour += 12;
+       } else
+               t->tm_hour = BCD2BIN(regs[2] & 0x3f);
+       t->tm_mday = BCD2BIN(regs[3]);
+       t->tm_mon = BCD2BIN(regs[4]) - 1;
+       t->tm_year = BCD2BIN(regs[5]) + 100;
+}
+
+static int time_to_menelaus(struct rtc_time *t, int regnum)
+{
+       int     hour, status;
+
+       status = menelaus_write_reg(regnum++, BIN2BCD(t->tm_sec));
+       if (status < 0)
+               goto fail;
+
+       status = menelaus_write_reg(regnum++, BIN2BCD(t->tm_min));
+       if (status < 0)
+               goto fail;
+
+       if (the_menelaus->rtc_control & RTC_CTRL_MODE12) {
+               hour = t->tm_hour + 1;
+               if (hour > 12)
+                       hour = RTC_HR_PM | BIN2BCD(hour - 12);
+               else
+                       hour = BIN2BCD(hour);
+       } else
+               hour = BIN2BCD(t->tm_hour);
+       status = menelaus_write_reg(regnum++, hour);
+       if (status < 0)
+               goto fail;
+
+       status = menelaus_write_reg(regnum++, BIN2BCD(t->tm_mday));
+       if (status < 0)
+               goto fail;
+
+       status = menelaus_write_reg(regnum++, BIN2BCD(t->tm_mon + 1));
+       if (status < 0)
+               goto fail;
+
+       status = menelaus_write_reg(regnum++, BIN2BCD(t->tm_year - 100));
+       if (status < 0)
+               goto fail;
+
+       return 0;
+fail:
+       dev_err(&the_menelaus->client->dev, "rtc write reg %02x, err %d\n",
+                       --regnum, status);
+       return status;
+}
+
+static int menelaus_read_time(struct device *dev, struct rtc_time *t)
+{
+       struct i2c_msg  msg[2];
+       char            regs[7];
+       int             status;
+
+       /* block read date and time registers */
+       regs[0] = MENELAUS_RTC_SEC;
+
+       msg[0].addr = MENELAUS_I2C_ADDRESS;
+       msg[0].flags = 0;
+       msg[0].len = 1;
+       msg[0].buf = regs;
+
+       msg[1].addr = MENELAUS_I2C_ADDRESS;
+       msg[1].flags = I2C_M_RD;
+       msg[1].len = sizeof(regs);
+       msg[1].buf = regs;
+
+       status = i2c_transfer(the_menelaus->client->adapter, msg, 2);
+       if (status != 2) {
+               dev_err(dev, "%s error %d\n", "read", status);
+               return -EIO;
+       }
+
+       menelaus_to_time(regs, t);
+       t->tm_wday = BCD2BIN(regs[6]);
+
+       return 0;
+}
+
+static int menelaus_set_time(struct device *dev, struct rtc_time *t)
+{
+       int             status;
+
+       /* write date and time registers */
+       status = time_to_menelaus(t, MENELAUS_RTC_SEC);
+       if (status < 0)
+               return status;
+       status = menelaus_write_reg(MENELAUS_RTC_WKDAY, BIN2BCD(t->tm_wday));
+       if (status < 0) {
+               dev_err(&the_menelaus->client->dev, "rtc write reg %02x, err %d\n",
+                               MENELAUS_RTC_WKDAY, status);
+               return status;
+       }
+
+       /* now commit the write */
+       status = menelaus_write_reg(MENELAUS_RTC_UPDATE, RTC_UPDATE_EVERY);
+       if (status < 0)
+               dev_err(&the_menelaus->client->dev, "rtc commit time, err %d\n",
+                               status);
+
+       return 0;
+}
+
+static int menelaus_read_alarm(struct device *dev, struct rtc_wkalrm *w)
+{
+       struct i2c_msg  msg[2];
+       char            regs[6];
+       int             status;
+
+       /* block read alarm registers */
+       regs[0] = MENELAUS_RTC_AL_SEC;
+
+       msg[0].addr = MENELAUS_I2C_ADDRESS;
+       msg[0].flags = 0;
+       msg[0].len = 1;
+       msg[0].buf = regs;
+
+       msg[1].addr = MENELAUS_I2C_ADDRESS;
+       msg[1].flags = I2C_M_RD;
+       msg[1].len = sizeof(regs);
+       msg[1].buf = regs;
+
+       status = i2c_transfer(the_menelaus->client->adapter, msg, 2);
+       if (status != 2) {
+               dev_err(dev, "%s error %d\n", "alarm read", status);
+               return -EIO;
+       }
+
+       menelaus_to_time(regs, &w->time);
+
+       w->enabled = !!(the_menelaus->rtc_control & RTC_CTRL_AL_EN);
+
+       /* NOTE we *could* check if actually pending... */
+       w->pending = 0;
+
+       return 0;
+}
+
+static int menelaus_set_alarm(struct device *dev, struct rtc_wkalrm *w)
+{
+       int             status;
+
+       if (the_menelaus->client->irq <= 0 && w->enabled)
+               return -ENODEV;
+
+       /* clear previous alarm enable */
+       if (the_menelaus->rtc_control & RTC_CTRL_AL_EN) {
+               the_menelaus->rtc_control &= ~RTC_CTRL_AL_EN;
+               status = menelaus_write_reg(MENELAUS_RTC_CTRL,
+                               the_menelaus->rtc_control);
+               if (status < 0)
+                       return status;
+       }
+
+       /* write alarm registers */
+       status = time_to_menelaus(&w->time, MENELAUS_RTC_AL_SEC);
+       if (status < 0)
+               return status;
+
+       /* enable alarm if requested */
+       if (w->enabled) {
+               the_menelaus->rtc_control |= RTC_CTRL_AL_EN;
+               status = menelaus_write_reg(MENELAUS_RTC_CTRL,
+                               the_menelaus->rtc_control);
+       }
+
+       return status;
+}
+
+#ifdef CONFIG_RTC_INTF_DEV
+
+static void menelaus_rtc_update_work(struct menelaus_chip *m)
+{
+       /* report 1/sec update */
+       local_irq_disable();
+       rtc_update_irq(m->rtc, 1, RTC_IRQF | RTC_UF);
+       local_irq_enable();
+}
+
+static int menelaus_ioctl(struct device *dev, unsigned cmd, unsigned long arg)
+{
+       int     status;
+
+       if (the_menelaus->client->irq <= 0)
+               return -ENOIOCTLCMD;
+
+       switch (cmd) {
+       /* alarm IRQ */
+       case RTC_AIE_ON:
+               if (the_menelaus->rtc_control & RTC_CTRL_AL_EN)
+                       return 0;
+               the_menelaus->rtc_control |= RTC_CTRL_AL_EN;
+               break;
+       case RTC_AIE_OFF:
+               if (!(the_menelaus->rtc_control & RTC_CTRL_AL_EN))
+                       return 0;
+               the_menelaus->rtc_control &= ~RTC_CTRL_AL_EN;
+               break;
+       /* 1/second "update" IRQ */
+       case RTC_UIE_ON:
+               if (the_menelaus->uie)
+                       return 0;
+               status = menelaus_remove_irq_work(MENELAUS_RTCTMR_IRQ);
+               status = menelaus_add_irq_work(MENELAUS_RTCTMR_IRQ,
+                               menelaus_rtc_update_work);
+               if (status == 0)
+                       the_menelaus->uie = 1;
+               return status;
+       case RTC_UIE_OFF:
+               if (!the_menelaus->uie)
+                       return 0;
+               status = menelaus_remove_irq_work(MENELAUS_RTCTMR_IRQ);
+               if (status == 0)
+                       the_menelaus->uie = 0;
+               return status;
+       default:
+               return -ENOIOCTLCMD;
+       }
+       return menelaus_write_reg(MENELAUS_RTC_CTRL, the_menelaus->rtc_control);
+}
+
+#else
+#define menelaus_ioctl NULL
+#endif
+
+/* REVISIT no compensation register support ... */
+
+static const struct rtc_class_ops menelaus_rtc_ops = {
+       .ioctl                  = menelaus_ioctl,
+       .read_time              = menelaus_read_time,
+       .set_time               = menelaus_set_time,
+       .read_alarm             = menelaus_read_alarm,
+       .set_alarm              = menelaus_set_alarm,
+};
+
+static void menelaus_rtc_alarm_work(struct menelaus_chip *m)
+{
+       /* report alarm */
+       local_irq_disable();
+       rtc_update_irq(m->rtc, 1, RTC_IRQF | RTC_AF);
+       local_irq_enable();
+
+       /* then disable it; alarms are oneshot */
+       the_menelaus->rtc_control &= ~RTC_CTRL_AL_EN;
+       menelaus_write_reg(MENELAUS_RTC_CTRL, the_menelaus->rtc_control);
+}
+
+static inline void menelaus_rtc_init(struct menelaus_chip *m)
+{
+       int     alarm = (m->client->irq > 0);
+
+       /* assume 32KDETEN pin is pulled high */
+       if (!(menelaus_read_reg(MENELAUS_OSC_CTRL) & 0x80)) {
+               dev_dbg(&m->client->dev, "no 32k oscillator\n");
+               return;
+       }
+
+       /* support RTC alarm; it can issue wakeups */
+       if (alarm) {
+               if (menelaus_add_irq_work(MENELAUS_RTCALM_IRQ,
+                               menelaus_rtc_alarm_work) < 0) {
+                       dev_err(&m->client->dev, "can't handle RTC alarm\n");
+                       return;
+               }
+               device_init_wakeup(&m->client->dev, 1);
+       }
+
+       /* be sure RTC is enabled; allow 1/sec irqs; leave 12hr mode alone */
+       m->rtc_control = menelaus_read_reg(MENELAUS_RTC_CTRL);
+       if (!(m->rtc_control & RTC_CTRL_RTC_EN)
+                       || (m->rtc_control & RTC_CTRL_AL_EN)
+                       || (m->rtc_control & RTC_CTRL_EVERY_MASK)) {
+               if (!(m->rtc_control & RTC_CTRL_RTC_EN)) {
+                       dev_warn(&m->client->dev, "rtc clock needs setting\n");
+                       m->rtc_control |= RTC_CTRL_RTC_EN;
+               }
+               m->rtc_control &= ~RTC_CTRL_EVERY_MASK;
+               m->rtc_control &= ~RTC_CTRL_AL_EN;
+               menelaus_write_reg(MENELAUS_RTC_CTRL, m->rtc_control);
+       }
+
+       m->rtc = rtc_device_register(DRIVER_NAME,
+                       &m->client->dev,
+                       &menelaus_rtc_ops, THIS_MODULE);
+       if (IS_ERR(m->rtc)) {
+               if (alarm) {
+                       menelaus_remove_irq_work(MENELAUS_RTCALM_IRQ);
+                       device_init_wakeup(&m->client->dev, 0);
+               }
+               dev_err(&m->client->dev, "can't register RTC: %d\n",
+                               (int) PTR_ERR(m->rtc));
+               the_menelaus->rtc = NULL;
+       }
+}
+
+#else
+
+static inline void menelaus_rtc_init(struct menelaus_chip *m)
+{
+       /* nothing */
+}
+
+#endif
+
+/*-----------------------------------------------------------------------*/
+
 static struct i2c_driver menelaus_i2c_driver;
 
 static int menelaus_probe(struct i2c_client *client)
@@ -838,6 +1188,8 @@ static int menelaus_probe(struct i2c_client *client)
        menelaus_write_reg(MENELAUS_INT_ACK2, 0xff);
        menelaus_write_reg(MENELAUS_INT_MASK1, 0xff);
        menelaus_write_reg(MENELAUS_INT_MASK2, 0xff);
+       menelaus->mask1 = 0xff;
+       menelaus->mask2 = 0xff;
 
        /* Set output buffer strengths */
        menelaus_write_reg(MENELAUS_MCT_CTRL1, 0x73);
@@ -871,6 +1223,8 @@ static int menelaus_probe(struct i2c_client *client)
                        goto fail2;
        }
 
+       menelaus_rtc_init(menelaus);
+
        return 0;
 fail2:
        free_irq(client->irq, menelaus);
index d54bc8f15b48dac6247d3981c17dc6b48c2d67b4..f0a04769afb839423ca78c0e89849c810804d14f 100644 (file)
@@ -223,6 +223,15 @@ config RTC_DRV_TWL4030
          This driver can also be built as a module. If so, the module
          will be called rtc-twl4030.
 
+config RTC_DRV_TWL92330
+       boolean "TI TWL92330/Menelaus"
+       depends on RTC_CLASS && I2C && MENELAUS
+       help
+         If you say yes here you get support for the RTC on the
+         TWL92330 "Menelaus" power mangement chip, used with OMAP2
+         platforms.  The support is integrated with the rest of
+         the Menelaus driver; it's not separate module.
+
 comment "SPI RTC drivers"
        depends on RTC_CLASS