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Commit 5c3d8a46 authored by Heiko Schocher's avatar Heiko Schocher Committed by Wolfram Sang
Browse files

i2c: davinci: add OF support 



add of support for the davinci i2c driver.

Signed-off-by: default avatarHeiko Schocher <hs@denx.de>
Signed-off-by: default avatarSekhar Nori <nsekhar@ti.com>

[wsa: fix indentation in the binding description]

Signed-off-by: default avatarWolfram Sang <w.sang@pengutronix.de>
parent 002f002d

Documentation/devicetree/bindings/i2c/davinci.txt

0 → 100644
+28 −0
Original line number Diff line number Diff line 
* Texas Instruments Davinci I2C



This file provides information, what the device node for the

davinci i2c interface contain.



Required properties:

- compatible: "ti,davinci-i2c";

- reg : Offset and length of the register set for the device



Recommended properties :

- interrupts : standard interrupt property.

- clock-frequency : desired I2C bus clock frequency in Hz.



Example (enbw_cmc board):

	i2c@1c22000 {

		compatible = "ti,davinci-i2c";

		reg = <0x22000 0x1000>;

		clock-frequency = <100000>;

		interrupts = <15>;

		interrupt-parent = <&intc>;

		#address-cells = <1>;

		#size-cells = <0>;



		dtt@48 {

			compatible = "national,lm75";

			reg = <0x48>;

		};

	};

drivers/i2c/busses/i2c-davinci.c

+37 −11
Original line number Diff line number Diff line
@@ -38,6 +38,8 @@ 
#include <linux/slab.h>

#include <linux/cpufreq.h>

#include <linux/gpio.h>

#include <linux/of_i2c.h>

#include <linux/of_device.h>



#include <mach/hardware.h>

#include <mach/i2c.h>
@@ -114,6 +116,7 @@ struct davinci_i2c_dev { 
	struct completion	xfr_complete;

	struct notifier_block	freq_transition;

#endif

	struct davinci_i2c_platform_data *pdata;

};



/* default platform data to use if not supplied in the platform_device */
@@ -155,7 +158,7 @@ static void generic_i2c_clock_pulse(unsigned int scl_pin) 
static void i2c_recover_bus(struct davinci_i2c_dev *dev)

{

	u32 flag = 0;

	struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;

	struct davinci_i2c_platform_data *pdata = dev->pdata;



	dev_err(dev->dev, "initiating i2c bus recovery\n");

	/* Send NACK to the slave */
@@ -163,7 +166,6 @@ static void i2c_recover_bus(struct davinci_i2c_dev *dev) 
	flag |=  DAVINCI_I2C_MDR_NACK;

	/* write the data into mode register */

	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);

	if (pdata)

	generic_i2c_clock_pulse(pdata->scl_pin);

	/* Send STOP */

	flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
@@ -187,7 +189,7 @@ static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev, 


static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev)

{

	struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;

	struct davinci_i2c_platform_data *pdata = dev->pdata;

	u16 psc;

	u32 clk;

	u32 d;
@@ -235,10 +237,7 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) 
 */

static int i2c_davinci_init(struct davinci_i2c_dev *dev)

{

	struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;



	if (!pdata)

		pdata = &davinci_i2c_platform_data_default;

	struct davinci_i2c_platform_data *pdata = dev->pdata;



	/* put I2C into reset */

	davinci_i2c_reset_ctrl(dev, 0);
@@ -260,6 +259,7 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev) 
	dev_dbg(dev->dev, "bus_freq = %dkHz, bus_delay = %d\n",

		pdata->bus_freq, pdata->bus_delay);





	/* Take the I2C module out of reset: */

	davinci_i2c_reset_ctrl(dev, 1);
@@ -308,13 +308,11 @@ static int 
i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)

{

	struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);

	struct davinci_i2c_platform_data *pdata = dev->dev->platform_data;

	struct davinci_i2c_platform_data *pdata = dev->pdata;

	u32 flag;

	u16 w;

	int r;



	if (!pdata)

		pdata = &davinci_i2c_platform_data_default;

	/* Introduce a delay, required for some boards (e.g Davinci EVM) */

	if (pdata->bus_delay)

		udelay(pdata->bus_delay);
@@ -635,6 +633,12 @@ static struct i2c_algorithm i2c_davinci_algo = { 
	.functionality	= i2c_davinci_func,

};



static const struct of_device_id davinci_i2c_of_match[] = {

	{.compatible = "ti,davinci-i2c", },

	{},

};

MODULE_DEVICE_TABLE(of, davinci_i2c_of_match);



static int davinci_i2c_probe(struct platform_device *pdev)

{

	struct davinci_i2c_dev *dev;
@@ -674,8 +678,27 @@ static int davinci_i2c_probe(struct platform_device *pdev) 
#endif

	dev->dev = get_device(&pdev->dev);

	dev->irq = irq->start;

	dev->pdata = dev->dev->platform_data;

	platform_set_drvdata(pdev, dev);



	if (!dev->pdata && pdev->dev.of_node) {

		u32 prop;



		dev->pdata = devm_kzalloc(&pdev->dev,

			sizeof(struct davinci_i2c_platform_data), GFP_KERNEL);

		if (!dev->pdata) {

			r = -ENOMEM;

			goto err_free_mem;

		}

		memcpy(dev->pdata, &davinci_i2c_platform_data_default,

			sizeof(struct davinci_i2c_platform_data));

		if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency",

			&prop))

			dev->pdata->bus_freq = prop / 1000;

	} else if (!dev->pdata) {

		dev->pdata = &davinci_i2c_platform_data_default;

	}



	dev->clk = clk_get(&pdev->dev, NULL);

	if (IS_ERR(dev->clk)) {

		r = -ENODEV;
@@ -711,6 +734,7 @@ static int davinci_i2c_probe(struct platform_device *pdev) 
	adap->algo = &i2c_davinci_algo;

	adap->dev.parent = &pdev->dev;

	adap->timeout = DAVINCI_I2C_TIMEOUT;

	adap->dev.of_node = pdev->dev.of_node;



	adap->nr = pdev->id;

	r = i2c_add_numbered_adapter(adap);
@@ -718,6 +742,7 @@ static int davinci_i2c_probe(struct platform_device *pdev) 
		dev_err(&pdev->dev, "failure adding adapter\n");

		goto err_free_irq;

	}

	of_i2c_register_devices(adap);



	return 0;
@@ -809,6 +834,7 @@ static struct platform_driver davinci_i2c_driver = { 
		.name	= "i2c_davinci",

		.owner	= THIS_MODULE,

		.pm	= davinci_i2c_pm_ops,

		.of_match_table = of_match_ptr(davinci_i2c_of_match),

	},

};