1 files changed, 131 insertions, 78 deletions

diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c
index 56caf6b2c3e5..c390e3355595 100644
--- a/drivers/rtc/rtc-rs5c372.c
+++ b/drivers/rtc/rtc-rs5c372.c
@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net>
  * Copyright (C) 2006 Tower Technologies
+ * Copyright (C) 2008 Paul Mundt
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -13,7 +14,7 @@
 #include <linux/rtc.h>
 #include <linux/bcd.h>
 
-#define DRV_VERSION "0.5"
+#define DRV_VERSION "0.6"
 
 
 /*
@@ -89,6 +90,7 @@ struct rs5c372 {
         enum rtc_type           type;
         unsigned                time24:1;
         unsigned                has_irq:1;
+        unsigned                smbus:1;
         char                    buf[17];
         char                    *regs;
 };
@@ -106,10 +108,25 @@ static int rs5c_get_regs(struct rs5c372 *rs5c)
          *
          * The first method doesn't work with the iop3xx adapter driver, on at
          * least 80219 chips; this works around that bug.
+         *
+         * The third method on the other hand doesn't work for the SMBus-only
+         * configurations, so we use the the first method there, stripping off
+         * the extra register in the process.
          */
-        if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
-                dev_warn(&client->dev, "can't read registers\n");
-                return -EIO;
+        if (rs5c->smbus) {
+                int addr = RS5C_ADDR(RS5C372_REG_SECS);
+                int size = sizeof(rs5c->buf) - 1;
+
+                if (i2c_smbus_read_i2c_block_data(client, addr, size,
+                                                  rs5c->buf + 1) != size) {
+                        dev_warn(&client->dev, "can't read registers\n");
+                        return -EIO;
+                }
+        } else {
+                if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
+                        dev_warn(&client->dev, "can't read registers\n");
+                        return -EIO;
+                }
         }
 
         dev_dbg(&client->dev,
@@ -187,6 +204,7 @@ static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
 {
         struct rs5c372  *rs5c = i2c_get_clientdata(client);
         unsigned char   buf[8];
+        int             addr;
 
         dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
                 "mday=%d, mon=%d, year=%d, wday=%d\n",
@@ -194,16 +212,16 @@ static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
                 tm->tm_sec, tm->tm_min, tm->tm_hour,
                 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
 
-        buf[0] = RS5C_ADDR(RS5C372_REG_SECS);
-        buf[1] = BIN2BCD(tm->tm_sec);
-        buf[2] = BIN2BCD(tm->tm_min);
-        buf[3] = rs5c_hr2reg(rs5c, tm->tm_hour);
-        buf[4] = BIN2BCD(tm->tm_wday);
-        buf[5] = BIN2BCD(tm->tm_mday);
-        buf[6] = BIN2BCD(tm->tm_mon + 1);
-        buf[7] = BIN2BCD(tm->tm_year - 100);
+        addr   = RS5C_ADDR(RS5C372_REG_SECS);
+        buf[0] = BIN2BCD(tm->tm_sec);
+        buf[1] = BIN2BCD(tm->tm_min);
+        buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
+        buf[3] = BIN2BCD(tm->tm_wday);
+        buf[4] = BIN2BCD(tm->tm_mday);
+        buf[5] = BIN2BCD(tm->tm_mon + 1);
+        buf[6] = BIN2BCD(tm->tm_year - 100);
 
-        if ((i2c_master_send(client, buf, 8)) != 8) {
+        if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
                 dev_err(&client->dev, "%s: write error\n", __func__);
                 return -EIO;
         }
@@ -266,16 +284,16 @@ rs5c_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 {
         struct i2c_client       *client = to_i2c_client(dev);
         struct rs5c372          *rs5c = i2c_get_clientdata(client);
-        unsigned char           buf[2];
-        int                     status;
+        unsigned char           buf;
+        int                     status, addr;
 
-        buf[1] = rs5c->regs[RS5C_REG_CTRL1];
+        buf = rs5c->regs[RS5C_REG_CTRL1];
         switch (cmd) {
         case RTC_UIE_OFF:
         case RTC_UIE_ON:
                 /* some 327a modes use a different IRQ pin for 1Hz irqs */
                 if (rs5c->type == rtc_rs5c372a
-                                && (buf[1] & RS5C372A_CTRL1_SL1))
+                                && (buf & RS5C372A_CTRL1_SL1))
                         return -ENOIOCTLCMD;
         case RTC_AIE_OFF:
         case RTC_AIE_ON:
@@ -293,28 +311,30 @@ rs5c_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
         if (status < 0)
                 return status;
 
-        buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
+        addr = RS5C_ADDR(RS5C_REG_CTRL1);
         switch (cmd) {
         case RTC_AIE_OFF:       /* alarm off */
-                buf[1] &= ~RS5C_CTRL1_AALE;
+                buf &= ~RS5C_CTRL1_AALE;
                 break;
         case RTC_AIE_ON:        /* alarm on */
-                buf[1] |= RS5C_CTRL1_AALE;
+                buf |= RS5C_CTRL1_AALE;
                 break;
         case RTC_UIE_OFF:       /* update off */
-                buf[1] &= ~RS5C_CTRL1_CT_MASK;
+                buf &= ~RS5C_CTRL1_CT_MASK;
                 break;
         case RTC_UIE_ON:        /* update on */
-                buf[1] &= ~RS5C_CTRL1_CT_MASK;
-                buf[1] |= RS5C_CTRL1_CT4;
+                buf &= ~RS5C_CTRL1_CT_MASK;
+                buf |= RS5C_CTRL1_CT4;
                 break;
         }
-        if ((i2c_master_send(client, buf, 2)) != 2) {
+
+        if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
                 printk(KERN_WARNING "%s: can't update alarm\n",
                         rs5c->rtc->name);
                 status = -EIO;
         } else
-                rs5c->regs[RS5C_REG_CTRL1] = buf[1];
+                rs5c->regs[RS5C_REG_CTRL1] = buf;
+
         return status;
 }
 
@@ -364,8 +384,8 @@ static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 {
         struct i2c_client       *client = to_i2c_client(dev);
         struct rs5c372          *rs5c = i2c_get_clientdata(client);
-        int                     status;
-        unsigned char           buf[4];
+        int                     status, addr, i;
+        unsigned char           buf[3];
 
         /* only handle up to 24 hours in the future, like RTC_ALM_SET */
         if (t->time.tm_mday != -1
@@ -380,33 +400,36 @@ static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
         if (status < 0)
                 return status;
         if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
-                buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
-                buf[1] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
-                if (i2c_master_send(client, buf, 2) != 2) {
+                addr = RS5C_ADDR(RS5C_REG_CTRL1);
+                buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
+                if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
                         pr_debug("%s: can't disable alarm\n", rs5c->rtc->name);
                         return -EIO;
                 }
-                rs5c->regs[RS5C_REG_CTRL1] = buf[1];
+                rs5c->regs[RS5C_REG_CTRL1] = buf[0];
         }
 
         /* set alarm */
-        buf[0] = RS5C_ADDR(RS5C_REG_ALARM_A_MIN);
-        buf[1] = BIN2BCD(t->time.tm_min);
-        buf[2] = rs5c_hr2reg(rs5c, t->time.tm_hour);
-        buf[3] = 0x7f;  /* any/all days */
-        if ((i2c_master_send(client, buf, 4)) != 4) {
-                pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
-                return -EIO;
+        buf[0] = BIN2BCD(t->time.tm_min);
+        buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
+        buf[2] = 0x7f;  /* any/all days */
+
+        for (i = 0; i < sizeof(buf); i++) {
+                addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
+                if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
+                        pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
+                        return -EIO;
+                }
         }
 
         /* ... and maybe enable its irq */
         if (t->enabled) {
-                buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
-                buf[1] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
-                if ((i2c_master_send(client, buf, 2)) != 2)
+                addr = RS5C_ADDR(RS5C_REG_CTRL1);
+                buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
+                if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
                         printk(KERN_WARNING "%s: can't enable alarm\n",
                                 rs5c->rtc->name);
-                rs5c->regs[RS5C_REG_CTRL1] = buf[1];
+                rs5c->regs[RS5C_REG_CTRL1] = buf[0];
         }
 
         return 0;
@@ -503,18 +526,74 @@ static void rs5c_sysfs_unregister(struct device *dev)
 
 static struct i2c_driver rs5c372_driver;
 
+static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
+{
+        unsigned char buf[2];
+        int addr, i, ret = 0;
+
+        if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
+                return ret;
+        rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
+
+        addr   = RS5C_ADDR(RS5C_REG_CTRL1);
+        buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
+        buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
+
+        /* use 24hr mode */
+        switch (rs5c372->type) {
+        case rtc_rs5c372a:
+        case rtc_rs5c372b:
+                buf[1] |= RS5C372_CTRL2_24;
+                rs5c372->time24 = 1;
+                break;
+        case rtc_rv5c386:
+        case rtc_rv5c387a:
+                buf[0] |= RV5C387_CTRL1_24;
+                rs5c372->time24 = 1;
+                break;
+        default:
+                /* impossible */
+                break;
+        }
+
+        for (i = 0; i < sizeof(buf); i++) {
+                addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
+                ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
+                if (unlikely(ret < 0))
+                        return ret;
+        }
+
+        rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
+        rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
+
+        return 0;
+}
+
 static int rs5c372_probe(struct i2c_client *client,
                          const struct i2c_device_id *id)
 {
         int err = 0;
+        int smbus_mode = 0;
         struct rs5c372 *rs5c372;
         struct rtc_time tm;
 
         dev_dbg(&client->dev, "%s\n", __func__);
 
-        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
-                err = -ENODEV;
-                goto exit;
+        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
+                        I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
+                /*
+                 * If we don't have any master mode adapter, try breaking
+                 * it down in to the barest of capabilities.
+                 */
+                if (i2c_check_functionality(client->adapter,
+                                I2C_FUNC_SMBUS_BYTE_DATA |
+                                I2C_FUNC_SMBUS_I2C_BLOCK))
+                        smbus_mode = 1;
+                else {
+                        /* Still no good, give up */
+                        err = -ENODEV;
+                        goto exit;
+                }
         }
 
         if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
@@ -528,6 +607,7 @@ static int rs5c372_probe(struct i2c_client *client,
 
         /* we read registers 0x0f then 0x00-0x0f; skip the first one */
         rs5c372->regs = &rs5c372->buf[1];
+        rs5c372->smbus = smbus_mode;
 
         err = rs5c_get_regs(rs5c372);
         if (err < 0)
@@ -559,38 +639,10 @@ static int rs5c372_probe(struct i2c_client *client,
         /* if the oscillator lost power and no other software (like
          * the bootloader) set it up, do it here.
          */
-        if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP) {
-                unsigned char buf[3];
-
-                rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
-
-                buf[0] = RS5C_ADDR(RS5C_REG_CTRL1);
-                buf[1] = rs5c372->regs[RS5C_REG_CTRL1];
-                buf[2] = rs5c372->regs[RS5C_REG_CTRL2];
-
-                /* use 24hr mode */
-                switch (rs5c372->type) {
-                case rtc_rs5c372a:
-                case rtc_rs5c372b:
-                        buf[2] |= RS5C372_CTRL2_24;
-                        rs5c372->time24 = 1;
-                        break;
-                case rtc_rv5c386:
-                case rtc_rv5c387a:
-                        buf[1] |= RV5C387_CTRL1_24;
-                        rs5c372->time24 = 1;
-                        break;
-                default:
-                        /* impossible */
-                        break;
-                }
-
-                if ((i2c_master_send(client, buf, 3)) != 3) {
-                        dev_err(&client->dev, "setup error\n");
-                        goto exit_kfree;
-                }
-                rs5c372->regs[RS5C_REG_CTRL1] = buf[1];
-                rs5c372->regs[RS5C_REG_CTRL2] = buf[2];
+        err = rs5c_oscillator_setup(rs5c372);
+        if (unlikely(err < 0)) {
+                dev_err(&client->dev, "setup error\n");
+                goto exit_kfree;
         }
 
         if (rs5c372_get_datetime(client, &tm) < 0)
@@ -667,7 +719,8 @@ module_exit(rs5c372_exit);
 
 MODULE_AUTHOR(
                 "Pavel Mironchik <pmironchik@optifacio.net>, "
-                "Alessandro Zummo <a.zummo@towertech.it>");
+                "Alessandro Zummo <a.zummo@towertech.it>, "
+                "Paul Mundt <lethal@linux-sh.org>");
 MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
 MODULE_LICENSE("GPL");
 MODULE_VERSION(DRV_VERSION);