Merge tag 'isci-for-3.5' into misc

isci update for 3.5

1/ Rework remote-node-context (RNC) handling for proper management of
   the silicon state machine in error handling and hot-plug conditions.
   Further details below, suffice to say if the RNC is mismanaged the
   silicon state machines may lock up.

2/ Refactor the initialization code to be reused for suspend/resume support

3/ Miscellaneous bug fixes to address discovery issues and hardware
   compatibility.

RNC rework details from Jeff Skirvin:

In the controller, devices as they appear on a SAS domain (or
direct-attached SATA devices) are represented by memory structures known
as "Remote Node Contexts" (RNCs).  These structures are transferred from
main memory to the controller using a set of register commands; these
commands include setting up the context ("posting"), removing the
context ("invalidating"), and commands to control the scheduling of
commands and connections to that remote device ("suspensions" and
"resumptions").  There is a similar path to control RNC scheduling from
the protocol engine, which interprets the results of command and data
transmission and reception.

In general, the controller chooses among non-suspended RNCs to find one
that has work requiring scheduling the transmission of command and data
frames to a target.  Likewise, when a target tries to return data back
to the initiator, the state of the RNC is used by the controller to
determine how to treat the incoming request. As an example, if the RNC
is in the state "TX/RX Suspended", incoming SSP connection requests from
the target will be rejected by the controller hardware.  When an RNC is
"TX Suspended", it will not be selected by the controller hardware to
start outgoing command or data operations (with certain priority-based
exceptions).

As mentioned above, there are two sources for management of the RNC
states: commands from driver software, and the result of transmission
and reception conditions of commands and data signaled by the controller
hardware.  As an example of the latter, if an outgoing SSP command ends
with a OPEN_REJECT(BAD_DESTINATION) status, the RNC state will
transition to the "TX Suspended" state, and this is signaled by the
controller hardware in the status to the completion of the pending
command as well as signaled in a controller hardware event.  Examples of
the former are included in the patch changelogs.

Driver software is required to suspend the RNC in a "TX/RX Suspended"
condition before any outstanding commands can be terminated.  Failure to
guarantee this can lead to a complete hardware hang condition.  Earlier
versions of the driver software did not guarantee that an RNC was
correctly managed before I/O termination, and so operated in an unsafe
way.

Further, the driver performed unnecessary contortions to preserve the
remote device command state and so was more complicated than it needed
to be.  A simplifying driver assumption is that once an I/O has entered
the error handler path without having completed in the target, the
requirement on the driver is that all use of the sas_task must end.
Beyond that, recovery of operation is dependent on libsas and other
components to reset, rediscover and reconfigure the device before normal
operation can restart.  In the driver, this simplifying assumption meant
that the RNC management could be reduced to entry into the suspended
state, terminating the targeted I/O request, and resuming the RNC as
needed for device-specific management such as an SSP Abort Task or LUN
Reset Management request.

1 files changed, 68 insertions, 46 deletions

diff --git a/drivers/mfd/twl6040-core.c b/drivers/mfd/twl6040-core.c
index b2d8e512d3cb..2d6bedadca09 100644
--- a/drivers/mfd/twl6040-core.c
+++ b/drivers/mfd/twl6040-core.c
@@ -30,7 +30,9 @@
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>
-#include <linux/i2c/twl.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/err.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/twl6040.h>
 
@@ -39,7 +41,7 @@
 int twl6040_reg_read(struct twl6040 *twl6040, unsigned int reg)
 {
 	int ret;
-	u8 val = 0;
+	unsigned int val;
 
 	mutex_lock(&twl6040->io_mutex);
 	/* Vibra control registers from cache */
@@ -47,7 +49,7 @@ int twl6040_reg_read(struct twl6040 *twl6040, unsigned int reg)
 		     reg == TWL6040_REG_VIBCTLR)) {
 		val = twl6040->vibra_ctrl_cache[VIBRACTRL_MEMBER(reg)];
 	} else {
-		ret = twl_i2c_read_u8(TWL_MODULE_AUDIO_VOICE, &val, reg);
+		ret = regmap_read(twl6040->regmap, reg, &val);
 		if (ret < 0) {
 			mutex_unlock(&twl6040->io_mutex);
 			return ret;
@@ -64,7 +66,7 @@ int twl6040_reg_write(struct twl6040 *twl6040, unsigned int reg, u8 val)
 	int ret;
 
 	mutex_lock(&twl6040->io_mutex);
-	ret = twl_i2c_write_u8(TWL_MODULE_AUDIO_VOICE, val, reg);
+	ret = regmap_write(twl6040->regmap, reg, val);
 	/* Cache the vibra control registers */
 	if (reg == TWL6040_REG_VIBCTLL || reg == TWL6040_REG_VIBCTLR)
 		twl6040->vibra_ctrl_cache[VIBRACTRL_MEMBER(reg)] = val;
@@ -77,16 +79,9 @@ EXPORT_SYMBOL(twl6040_reg_write);
 int twl6040_set_bits(struct twl6040 *twl6040, unsigned int reg, u8 mask)
 {
 	int ret;
-	u8 val;
 
 	mutex_lock(&twl6040->io_mutex);
-	ret = twl_i2c_read_u8(TWL_MODULE_AUDIO_VOICE, &val, reg);
-	if (ret)
-		goto out;
-
-	val |= mask;
-	ret = twl_i2c_write_u8(TWL_MODULE_AUDIO_VOICE, val, reg);
-out:
+	ret = regmap_update_bits(twl6040->regmap, reg, mask, mask);
 	mutex_unlock(&twl6040->io_mutex);
 	return ret;
 }
@@ -95,16 +90,9 @@ EXPORT_SYMBOL(twl6040_set_bits);
 int twl6040_clear_bits(struct twl6040 *twl6040, unsigned int reg, u8 mask)
 {
 	int ret;
-	u8 val;
 
 	mutex_lock(&twl6040->io_mutex);
-	ret = twl_i2c_read_u8(TWL_MODULE_AUDIO_VOICE, &val, reg);
-	if (ret)
-		goto out;
-
-	val &= ~mask;
-	ret = twl_i2c_write_u8(TWL_MODULE_AUDIO_VOICE, val, reg);
-out:
+	ret = regmap_update_bits(twl6040->regmap, reg, mask, 0);
 	mutex_unlock(&twl6040->io_mutex);
 	return ret;
 }
@@ -494,32 +482,58 @@ static struct resource twl6040_codec_rsrc[] = {
 	},
 };
 
-static int __devinit twl6040_probe(struct platform_device *pdev)
+static bool twl6040_readable_reg(struct device *dev, unsigned int reg)
 {
-	struct twl4030_audio_data *pdata = pdev->dev.platform_data;
+	/* Register 0 is not readable */
+	if (!reg)
+		return false;
+	return true;
+}
+
+static struct regmap_config twl6040_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = TWL6040_REG_STATUS, /* 0x2e */
+
+	.readable_reg = twl6040_readable_reg,
+};
+
+static int __devinit twl6040_probe(struct i2c_client *client,
+				     const struct i2c_device_id *id)
+{
+	struct twl6040_platform_data *pdata = client->dev.platform_data;
 	struct twl6040 *twl6040;
 	struct mfd_cell *cell = NULL;
 	int ret, children = 0;
 
 	if (!pdata) {
-		dev_err(&pdev->dev, "Platform data is missing\n");
+		dev_err(&client->dev, "Platform data is missing\n");
 		return -EINVAL;
 	}
 
 	/* In order to operate correctly we need valid interrupt config */
-	if (!pdata->naudint_irq || !pdata->irq_base) {
-		dev_err(&pdev->dev, "Invalid IRQ configuration\n");
+	if (!client->irq || !pdata->irq_base) {
+		dev_err(&client->dev, "Invalid IRQ configuration\n");
 		return -EINVAL;
 	}
 
-	twl6040 = kzalloc(sizeof(struct twl6040), GFP_KERNEL);
-	if (!twl6040)
-		return -ENOMEM;
+	twl6040 = devm_kzalloc(&client->dev, sizeof(struct twl6040),
+			       GFP_KERNEL);
+	if (!twl6040) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	twl6040->regmap = regmap_init_i2c(client, &twl6040_regmap_config);
+	if (IS_ERR(twl6040->regmap)) {
+		ret = PTR_ERR(twl6040->regmap);
+		goto err;
+	}
 
-	platform_set_drvdata(pdev, twl6040);
+	i2c_set_clientdata(client, twl6040);
 
-	twl6040->dev = &pdev->dev;
-	twl6040->irq = pdata->naudint_irq;
+	twl6040->dev = &client->dev;
+	twl6040->irq = client->irq;
 	twl6040->irq_base = pdata->irq_base;
 
 	mutex_init(&twl6040->mutex);
@@ -588,12 +602,12 @@ static int __devinit twl6040_probe(struct platform_device *pdev)
 	}
 
 	if (children) {
-		ret = mfd_add_devices(&pdev->dev, pdev->id, twl6040->cells,
+		ret = mfd_add_devices(&client->dev, -1, twl6040->cells,
 				      children, NULL, 0);
 		if (ret)
 			goto mfd_err;
 	} else {
-		dev_err(&pdev->dev, "No platform data found for children\n");
+		dev_err(&client->dev, "No platform data found for children\n");
 		ret = -ENODEV;
 		goto mfd_err;
 	}
@@ -608,14 +622,15 @@ gpio2_err:
 	if (gpio_is_valid(twl6040->audpwron))
 		gpio_free(twl6040->audpwron);
 gpio1_err:
-	platform_set_drvdata(pdev, NULL);
-	kfree(twl6040);
+	i2c_set_clientdata(client, NULL);
+	regmap_exit(twl6040->regmap);
+err:
 	return ret;
 }
 
-static int __devexit twl6040_remove(struct platform_device *pdev)
+static int __devexit twl6040_remove(struct i2c_client *client)
 {
-	struct twl6040 *twl6040 = platform_get_drvdata(pdev);
+	struct twl6040 *twl6040 = i2c_get_clientdata(client);
 
 	if (twl6040->power_count)
 		twl6040_power(twl6040, 0);
@@ -626,23 +641,30 @@ static int __devexit twl6040_remove(struct platform_device *pdev)
 	free_irq(twl6040->irq_base + TWL6040_IRQ_READY, twl6040);
 	twl6040_irq_exit(twl6040);
 
-	mfd_remove_devices(&pdev->dev);
-	platform_set_drvdata(pdev, NULL);
-	kfree(twl6040);
+	mfd_remove_devices(&client->dev);
+	i2c_set_clientdata(client, NULL);
+	regmap_exit(twl6040->regmap);
 
 	return 0;
 }
 
-static struct platform_driver twl6040_driver = {
+static const struct i2c_device_id twl6040_i2c_id[] = {
+	{ "twl6040", 0, },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, twl6040_i2c_id);
+
+static struct i2c_driver twl6040_driver = {
+	.driver = {
+		.name = "twl6040",
+		.owner = THIS_MODULE,
+	},
 	.probe		= twl6040_probe,
 	.remove		= __devexit_p(twl6040_remove),
-	.driver		= {
-		.owner	= THIS_MODULE,
-		.name	= "twl6040",
-	},
+	.id_table	= twl6040_i2c_id,
 };
 
-module_platform_driver(twl6040_driver);
+module_i2c_driver(twl6040_driver);
 
 MODULE_DESCRIPTION("TWL6040 MFD");
 MODULE_AUTHOR("Misael Lopez Cruz <misael.lopez@ti.com>");