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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-28 13:43:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-28 13:43:12 -0700
commita410963ba4c0c768302f0298e258b1ee940e8316 (patch)
treef262f101a5bf752ce14775da080aed5fbaf73f0e /drivers/i2c/busses/i2c-tegra.c
parentf7da9cdf45cbbad5029d4858dcbc0134e06084ed (diff)
parent5db20c49e2d6581797c17057e068d89d6677aa24 (diff)
downloadlinux-a410963ba4c0c768302f0298e258b1ee940e8316.tar.gz
Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
Pull embedded i2c changes from Wolfram Sang:
 "Changes for the "embedded" part of the I2C subsystem:

   - lots of devicetree conversions of drivers (and preparations for
     that)
   - big cleanups for drivers for OMAP, Tegra, Nomadik, Blackfin
   - Rafael's struct dev_pm_ops conversion patches for I2C
   - usual driver cleanups and fixes

  All patches have been in linux-next for an apropriate time and all
  patches touching files outside of i2c-folders should have proper acks
  from the maintainers."

* 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux: (60 commits)
  Revert "i2c: tegra: convert normal suspend/resume to *_noirq"
  I2C: MV64XYZ: Add Device Tree support
  i2c: stu300: use devm managed resources
  i2c: i2c-ocores: support for 16bit and 32bit IO
  V4L/DVB: mfd: use reg_shift instead of regstep
  i2c: i2c-ocores: Use reg-shift property
  i2c: i2c-ocores: DT bindings and minor fixes.
  i2c: mv64xxxx: remove EXPERIMENTAL tag
  i2c-s3c2410: Use plain pm_runtime_put()
  i2c: s3c2410: Fix pointer type passed to of_match_node()
  i2c: mxs: Set I2C timing registers for mxs-i2c
  i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.
  i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.
  i2c:i2c-bfin-twi: include twi head file
  i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.
  i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is reset unexpectedly.
  i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.
  i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon certain transfer scenarios".
  i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.
  i2c-mv64xxxx: allow more than one driver instance
  ...

Conflicts:
	drivers/i2c/busses/i2c-nomadik.c
Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r--drivers/i2c/busses/i2c-tegra.c122
1 files changed, 59 insertions, 63 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 3da7ee3eb505..66eb53fac202 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -97,8 +97,21 @@
 #define I2C_HEADER_10BIT_ADDR			(1<<18)
 #define I2C_HEADER_IE_ENABLE			(1<<17)
 #define I2C_HEADER_REPEAT_START			(1<<16)
+#define I2C_HEADER_CONTINUE_XFER		(1<<15)
 #define I2C_HEADER_MASTER_ADDR_SHIFT		12
 #define I2C_HEADER_SLAVE_ADDR_SHIFT		1
+/*
+ * msg_end_type: The bus control which need to be send at end of transfer.
+ * @MSG_END_STOP: Send stop pulse at end of transfer.
+ * @MSG_END_REPEAT_START: Send repeat start at end of transfer.
+ * @MSG_END_CONTINUE: The following on message is coming and so do not send
+ *		stop or repeat start.
+ */
+enum msg_end_type {
+	MSG_END_STOP,
+	MSG_END_REPEAT_START,
+	MSG_END_CONTINUE,
+};
 
 /**
  * struct tegra_i2c_dev	- per device i2c context
@@ -106,7 +119,6 @@
  * @adapter: core i2c layer adapter information
  * @clk: clock reference for i2c controller
  * @i2c_clk: clock reference for i2c bus
- * @iomem: memory resource for registers
  * @base: ioremapped registers cookie
  * @cont_id: i2c controller id, used for for packet header
  * @irq: irq number of transfer complete interrupt
@@ -124,7 +136,6 @@ struct tegra_i2c_dev {
 	struct i2c_adapter adapter;
 	struct clk *clk;
 	struct clk *i2c_clk;
-	struct resource *iomem;
 	void __iomem *base;
 	int cont_id;
 	int irq;
@@ -165,6 +176,10 @@ static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
 	unsigned long reg)
 {
 	writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
+
+	/* Read back register to make sure that register writes completed */
+	if (reg != I2C_TX_FIFO)
+		readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
 }
 
 static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
@@ -449,7 +464,7 @@ err:
 }
 
 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
-	struct i2c_msg *msg, int stop)
+	struct i2c_msg *msg, enum msg_end_type end_state)
 {
 	u32 packet_header;
 	u32 int_mask;
@@ -476,7 +491,9 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 	i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
 
 	packet_header = I2C_HEADER_IE_ENABLE;
-	if (!stop)
+	if (end_state == MSG_END_CONTINUE)
+		packet_header |= I2C_HEADER_CONTINUE_XFER;
+	else if (end_state == MSG_END_REPEAT_START)
 		packet_header |= I2C_HEADER_REPEAT_START;
 	if (msg->flags & I2C_M_TEN) {
 		packet_header |= msg->addr;
@@ -548,8 +565,14 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 
 	clk_prepare_enable(i2c_dev->clk);
 	for (i = 0; i < num; i++) {
-		int stop = (i == (num - 1)) ? 1  : 0;
-		ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], stop);
+		enum msg_end_type end_type = MSG_END_STOP;
+		if (i < (num - 1)) {
+			if (msgs[i + 1].flags & I2C_M_NOSTART)
+				end_type = MSG_END_CONTINUE;
+			else
+				end_type = MSG_END_REPEAT_START;
+		}
+		ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type);
 		if (ret)
 			break;
 	}
@@ -559,7 +582,8 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 
 static u32 tegra_i2c_func(struct i2c_adapter *adap)
 {
-	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR |
+		I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
 }
 
 static const struct i2c_algorithm tegra_i2c_algo = {
@@ -572,7 +596,6 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
 	struct tegra_i2c_dev *i2c_dev;
 	struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data;
 	struct resource *res;
-	struct resource *iomem;
 	struct clk *clk;
 	struct clk *i2c_clk;
 	const unsigned int *prop;
@@ -585,50 +608,41 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "no mem resource\n");
 		return -EINVAL;
 	}
-	iomem = request_mem_region(res->start, resource_size(res), pdev->name);
-	if (!iomem) {
-		dev_err(&pdev->dev, "I2C region already claimed\n");
-		return -EBUSY;
-	}
 
-	base = ioremap(iomem->start, resource_size(iomem));
+	base = devm_request_and_ioremap(&pdev->dev, res);
 	if (!base) {
-		dev_err(&pdev->dev, "Cannot ioremap I2C region\n");
-		return -ENOMEM;
+		dev_err(&pdev->dev, "Cannot request/ioremap I2C registers\n");
+		return -EADDRNOTAVAIL;
 	}
 
 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!res) {
 		dev_err(&pdev->dev, "no irq resource\n");
-		ret = -EINVAL;
-		goto err_iounmap;
+		return -EINVAL;
 	}
 	irq = res->start;
 
-	clk = clk_get(&pdev->dev, NULL);
+	clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "missing controller clock");
-		ret = PTR_ERR(clk);
-		goto err_release_region;
+		return PTR_ERR(clk);
 	}
 
-	i2c_clk = clk_get(&pdev->dev, "i2c");
+	i2c_clk = devm_clk_get(&pdev->dev, "i2c");
 	if (IS_ERR(i2c_clk)) {
 		dev_err(&pdev->dev, "missing bus clock");
-		ret = PTR_ERR(i2c_clk);
-		goto err_clk_put;
+		return PTR_ERR(i2c_clk);
 	}
 
-	i2c_dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL);
+	i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
 	if (!i2c_dev) {
-		ret = -ENOMEM;
-		goto err_i2c_clk_put;
+		dev_err(&pdev->dev, "Could not allocate struct tegra_i2c_dev");
+		return -ENOMEM;
 	}
 
 	i2c_dev->base = base;
 	i2c_dev->clk = clk;
 	i2c_dev->i2c_clk = i2c_clk;
-	i2c_dev->iomem = iomem;
 	i2c_dev->adapter.algo = &tegra_i2c_algo;
 	i2c_dev->irq = irq;
 	i2c_dev->cont_id = pdev->id;
@@ -657,13 +671,14 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
 	ret = tegra_i2c_init(i2c_dev);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to initialize i2c controller");
-		goto err_free;
+		return ret;
 	}
 
-	ret = request_irq(i2c_dev->irq, tegra_i2c_isr, 0, pdev->name, i2c_dev);
+	ret = devm_request_irq(&pdev->dev, i2c_dev->irq,
+			tegra_i2c_isr, 0, pdev->name, i2c_dev);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
-		goto err_free;
+		return ret;
 	}
 
 	clk_prepare_enable(i2c_dev->i2c_clk);
@@ -681,45 +696,26 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
 	ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to add I2C adapter\n");
-		goto err_free_irq;
+		clk_disable_unprepare(i2c_dev->i2c_clk);
+		return ret;
 	}
 
 	of_i2c_register_devices(&i2c_dev->adapter);
 
 	return 0;
-err_free_irq:
-	free_irq(i2c_dev->irq, i2c_dev);
-err_free:
-	kfree(i2c_dev);
-err_i2c_clk_put:
-	clk_put(i2c_clk);
-err_clk_put:
-	clk_put(clk);
-err_release_region:
-	release_mem_region(iomem->start, resource_size(iomem));
-err_iounmap:
-	iounmap(base);
-	return ret;
 }
 
 static int __devexit tegra_i2c_remove(struct platform_device *pdev)
 {
 	struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
 	i2c_del_adapter(&i2c_dev->adapter);
-	free_irq(i2c_dev->irq, i2c_dev);
-	clk_put(i2c_dev->i2c_clk);
-	clk_put(i2c_dev->clk);
-	release_mem_region(i2c_dev->iomem->start,
-		resource_size(i2c_dev->iomem));
-	iounmap(i2c_dev->base);
-	kfree(i2c_dev);
 	return 0;
 }
 
 #ifdef CONFIG_PM
-static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state)
+static int tegra_i2c_suspend(struct device *dev)
 {
-	struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+	struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
 
 	i2c_lock_adapter(&i2c_dev->adapter);
 	i2c_dev->is_suspended = true;
@@ -728,9 +724,9 @@ static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state)
 	return 0;
 }
 
-static int tegra_i2c_resume(struct platform_device *pdev)
+static int tegra_i2c_resume(struct device *dev)
 {
-	struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+	struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
 	int ret;
 
 	i2c_lock_adapter(&i2c_dev->adapter);
@@ -748,6 +744,11 @@ static int tegra_i2c_resume(struct platform_device *pdev)
 
 	return 0;
 }
+
+static SIMPLE_DEV_PM_OPS(tegra_i2c_pm, tegra_i2c_suspend, tegra_i2c_resume);
+#define TEGRA_I2C_PM	(&tegra_i2c_pm)
+#else
+#define TEGRA_I2C_PM	NULL
 #endif
 
 #if defined(CONFIG_OF)
@@ -758,21 +759,16 @@ static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
 	{},
 };
 MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
-#else
-#define tegra_i2c_of_match NULL
 #endif
 
 static struct platform_driver tegra_i2c_driver = {
 	.probe   = tegra_i2c_probe,
 	.remove  = __devexit_p(tegra_i2c_remove),
-#ifdef CONFIG_PM
-	.suspend = tegra_i2c_suspend,
-	.resume  = tegra_i2c_resume,
-#endif
 	.driver  = {
 		.name  = "tegra-i2c",
 		.owner = THIS_MODULE,
-		.of_match_table = tegra_i2c_of_match,
+		.of_match_table = of_match_ptr(tegra_i2c_of_match),
+		.pm    = TEGRA_I2C_PM,
 	},
 };