Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:

 - Fix timing problems in applesmc driver

 - Improve device removal in jc42 driver

 - Fix build warning in acp_power_meter driver

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (applesmc) Decode and act on read/write status codes
  hwmon: (jc42) Don't reset hysteresis on device removal
  hwmon: (jc42) Simplify hysteresis mask
  hwmon: (acpi_power_meter) Fix build warning

3 files changed, 66 insertions, 34 deletions

diff --git a/drivers/hwmon/acpi_power_meter.c b/drivers/hwmon/acpi_power_meter.c
index 563c02904ddf..23ab3c496b05 100644
--- a/drivers/hwmon/acpi_power_meter.c
+++ b/drivers/hwmon/acpi_power_meter.c
@@ -927,6 +927,8 @@ static int acpi_power_meter_remove(struct acpi_device *device, int type)
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+
 static int acpi_power_meter_resume(struct device *dev)
 {
 	struct acpi_power_meter_resource *resource;
@@ -944,6 +946,8 @@ static int acpi_power_meter_resume(struct device *dev)
 	return 0;
 }
 
+#endif /* CONFIG_PM_SLEEP */
+
 static SIMPLE_DEV_PM_OPS(acpi_power_meter_pm, NULL, acpi_power_meter_resume);
 
 static struct acpi_driver acpi_power_meter_driver = {
diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
index 4d937a18fadb..282708860517 100644
--- a/drivers/hwmon/applesmc.c
+++ b/drivers/hwmon/applesmc.c
@@ -55,9 +55,9 @@
 
 /* wait up to 32 ms for a status change. */
 #define APPLESMC_MIN_WAIT	0x0010
+#define APPLESMC_RETRY_WAIT	0x0100
 #define APPLESMC_MAX_WAIT	0x8000
 
-#define APPLESMC_STATUS_MASK	0x0f
 #define APPLESMC_READ_CMD	0x10
 #define APPLESMC_WRITE_CMD	0x11
 #define APPLESMC_GET_KEY_BY_INDEX_CMD	0x12
@@ -162,51 +162,68 @@ static unsigned int key_at_index;
 static struct workqueue_struct *applesmc_led_wq;
 
 /*
- * __wait_status - Wait up to 32ms for the status port to get a certain value
- * (masked with 0x0f), returning zero if the value is obtained.  Callers must
+ * wait_read - Wait for a byte to appear on SMC port. Callers must
  * hold applesmc_lock.
  */
-static int __wait_status(u8 val)
+static int wait_read(void)
 {
+	u8 status;
 	int us;
-
-	val = val & APPLESMC_STATUS_MASK;
-
 	for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
 		udelay(us);
-		if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == val)
+		status = inb(APPLESMC_CMD_PORT);
+		/* read: wait for smc to settle */
+		if (status & 0x01)
 			return 0;
 	}
 
+	pr_warn("wait_read() fail: 0x%02x\n", status);
 	return -EIO;
 }
 
 /*
- * special treatment of command port - on newer macbooks, it seems necessary
- * to resend the command byte before polling the status again. Callers must
- * hold applesmc_lock.
+ * send_byte - Write to SMC port, retrying when necessary. Callers
+ * must hold applesmc_lock.
  */
-static int send_command(u8 cmd)
+static int send_byte(u8 cmd, u16 port)
 {
+	u8 status;
 	int us;
+
+	outb(cmd, port);
 	for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
-		outb(cmd, APPLESMC_CMD_PORT);
 		udelay(us);
-		if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == 0x0c)
+		status = inb(APPLESMC_CMD_PORT);
+		/* write: wait for smc to settle */
+		if (status & 0x02)
+			continue;
+		/* ready: cmd accepted, return */
+		if (status & 0x04)
 			return 0;
+		/* timeout: give up */
+		if (us << 1 == APPLESMC_MAX_WAIT)
+			break;
+		/* busy: long wait and resend */
+		udelay(APPLESMC_RETRY_WAIT);
+		outb(cmd, port);
 	}
+
+	pr_warn("send_byte(0x%02x, 0x%04x) fail: 0x%02x\n", cmd, port, status);
 	return -EIO;
 }
 
+static int send_command(u8 cmd)
+{
+	return send_byte(cmd, APPLESMC_CMD_PORT);
+}
+
 static int send_argument(const char *key)
 {
 	int i;
 
-	for (i = 0; i < 4; i++) {
-		outb(key[i], APPLESMC_DATA_PORT);
-		if (__wait_status(0x04))
+	for (i = 0; i < 4; i++)
+		if (send_byte(key[i], APPLESMC_DATA_PORT))
 			return -EIO;
-	}
 	return 0;
 }
 
@@ -219,11 +236,14 @@ static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
 		return -EIO;
 	}
 
-	outb(len, APPLESMC_DATA_PORT);
+	if (send_byte(len, APPLESMC_DATA_PORT)) {
+		pr_warn("%.4s: read len fail\n", key);
+		return -EIO;
+	}
 
 	for (i = 0; i < len; i++) {
-		if (__wait_status(0x05)) {
-			pr_warn("%.4s: read data fail\n", key);
+		if (wait_read()) {
+			pr_warn("%.4s: read data[%d] fail\n", key, i);
 			return -EIO;
 		}
 		buffer[i] = inb(APPLESMC_DATA_PORT);
@@ -241,14 +261,16 @@ static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
 		return -EIO;
 	}
 
-	outb(len, APPLESMC_DATA_PORT);
+	if (send_byte(len, APPLESMC_DATA_PORT)) {
+		pr_warn("%.4s: write len fail\n", key);
+		return -EIO;
+	}
 
 	for (i = 0; i < len; i++) {
-		if (__wait_status(0x04)) {
+		if (send_byte(buffer[i], APPLESMC_DATA_PORT)) {
 			pr_warn("%s: write data fail\n", key);
 			return -EIO;
 		}
-		outb(buffer[i], APPLESMC_DATA_PORT);
 	}
 
 	return 0;
diff --git a/drivers/hwmon/jc42.c b/drivers/hwmon/jc42.c
index e72ba5d2a824..e21e43c13156 100644
--- a/drivers/hwmon/jc42.c
+++ b/drivers/hwmon/jc42.c
@@ -57,7 +57,7 @@ static const unsigned short normal_i2c[] = {
 #define JC42_CFG_EVENT_LOCK	(1 << 7)
 #define JC42_CFG_SHUTDOWN	(1 << 8)
 #define JC42_CFG_HYST_SHIFT	9
-#define JC42_CFG_HYST_MASK	0x03
+#define JC42_CFG_HYST_MASK	(0x03 << 9)
 
 /* Capabilities */
 #define JC42_CAP_RANGE		(1 << 2)
@@ -287,8 +287,8 @@ static ssize_t show_temp_crit_hyst(struct device *dev,
 		return PTR_ERR(data);
 
 	temp = jc42_temp_from_reg(data->temp_crit);
-	hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)
-			       & JC42_CFG_HYST_MASK];
+	hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
+			       >> JC42_CFG_HYST_SHIFT];
 	return sprintf(buf, "%d\n", temp - hyst);
 }
 
@@ -302,8 +302,8 @@ static ssize_t show_temp_max_hyst(struct device *dev,
 		return PTR_ERR(data);
 
 	temp = jc42_temp_from_reg(data->temp_max);
-	hyst = jc42_hysteresis[(data->config >> JC42_CFG_HYST_SHIFT)
-			       & JC42_CFG_HYST_MASK];
+	hyst = jc42_hysteresis[(data->config & JC42_CFG_HYST_MASK)
+			       >> JC42_CFG_HYST_SHIFT];
 	return sprintf(buf, "%d\n", temp - hyst);
 }
 
@@ -362,8 +362,7 @@ static ssize_t set_temp_crit_hyst(struct device *dev,
 	}
 
 	mutex_lock(&data->update_lock);
-	data->config = (data->config
-			& ~(JC42_CFG_HYST_MASK << JC42_CFG_HYST_SHIFT))
+	data->config = (data->config & ~JC42_CFG_HYST_MASK)
 	  | (hyst << JC42_CFG_HYST_SHIFT);
 	err = i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG,
 					   data->config);
@@ -535,9 +534,16 @@ static int jc42_remove(struct i2c_client *client)
 	struct jc42_data *data = i2c_get_clientdata(client);
 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&client->dev.kobj, &jc42_group);
-	if (data->config != data->orig_config)
-		i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG,
-					     data->orig_config);
+
+	/* Restore original configuration except hysteresis */
+	if ((data->config & ~JC42_CFG_HYST_MASK) !=
+	    (data->orig_config & ~JC42_CFG_HYST_MASK)) {
+		int config;
+
+		config = (data->orig_config & ~JC42_CFG_HYST_MASK)
+		  | (data->config & JC42_CFG_HYST_MASK);
+		i2c_smbus_write_word_swapped(client, JC42_REG_CONFIG, config);
+	}
 	return 0;
 }