Commit 6327edce authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 

Pull i2c fixes from Wolfram Sang:
 "Two driver bugfixes, a documentation fix, and a removal of a spec
  violation for the bus recovery algorithm in the core"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: fix bus recovery stop mode timing
  i2c: bcm2835: Store pointer to bus clock
  dt-bindings: i2c: at91: fix i2c-sda-hold-time-ns documentation for sam9x60
  i2c: at91: fix clk_offset for sam9x60
parents 606e9ad2 cf8ce8b8

Documentation/devicetree/bindings/i2c/i2c-at91.txt

+4 −2
Original line number Diff line number Diff line
@@ -18,8 +18,10 @@ Optional properties: 
- dma-names: should contain "tx" and "rx".

- atmel,fifo-size: maximum number of data the RX and TX FIFOs can store for FIFO

  capable I2C controllers.

- i2c-sda-hold-time-ns: TWD hold time, only available for "atmel,sama5d4-i2c"

  and "atmel,sama5d2-i2c".

- i2c-sda-hold-time-ns: TWD hold time, only available for:

	"atmel,sama5d4-i2c",

	"atmel,sama5d2-i2c",

	"microchip,sam9x60-i2c".

- Child nodes conforming to i2c bus binding



Examples :

drivers/i2c/busses/i2c-at91-core.c

+1 −1
Original line number Diff line number Diff line
@@ -174,7 +174,7 @@ static struct at91_twi_pdata sama5d2_config = { 


static struct at91_twi_pdata sam9x60_config = {

	.clk_max_div = 7,

	.clk_offset = 4,

	.clk_offset = 3,

	.has_unre_flag = true,

	.has_alt_cmd = true,

	.has_hold_field = true,

drivers/i2c/busses/i2c-bcm2835.c

+8 −9
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ struct bcm2835_i2c_dev { 
	struct i2c_adapter adapter;

	struct completion completion;

	struct i2c_msg *curr_msg;

	struct clk *bus_clk;

	int num_msgs;

	u32 msg_err;

	u8 *msg_buf;
@@ -404,7 +405,6 @@ static int bcm2835_i2c_probe(struct platform_device *pdev) 
	struct resource *mem, *irq;

	int ret;

	struct i2c_adapter *adap;

	struct clk *bus_clk;

	struct clk *mclk;

	u32 bus_clk_rate;
@@ -427,11 +427,11 @@ static int bcm2835_i2c_probe(struct platform_device *pdev) 
		return PTR_ERR(mclk);

	}



	bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev);

	i2c_dev->bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev);



	if (IS_ERR(bus_clk)) {

	if (IS_ERR(i2c_dev->bus_clk)) {

		dev_err(&pdev->dev, "Could not register clock\n");

		return PTR_ERR(bus_clk);

		return PTR_ERR(i2c_dev->bus_clk);

	}



	ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency",
@@ -442,13 +442,13 @@ static int bcm2835_i2c_probe(struct platform_device *pdev) 
		bus_clk_rate = 100000;

	}



	ret = clk_set_rate_exclusive(bus_clk, bus_clk_rate);

	ret = clk_set_rate_exclusive(i2c_dev->bus_clk, bus_clk_rate);

	if (ret < 0) {

		dev_err(&pdev->dev, "Could not set clock frequency\n");

		return ret;

	}



	ret = clk_prepare_enable(bus_clk);

	ret = clk_prepare_enable(i2c_dev->bus_clk);

	if (ret) {

		dev_err(&pdev->dev, "Couldn't prepare clock");

		return ret;
@@ -491,10 +491,9 @@ static int bcm2835_i2c_probe(struct platform_device *pdev) 
static int bcm2835_i2c_remove(struct platform_device *pdev)

{

	struct bcm2835_i2c_dev *i2c_dev = platform_get_drvdata(pdev);

	struct clk *bus_clk = devm_clk_get(i2c_dev->dev, "div");



	clk_rate_exclusive_put(bus_clk);

	clk_disable_unprepare(bus_clk);

	clk_rate_exclusive_put(i2c_dev->bus_clk);

	clk_disable_unprepare(i2c_dev->bus_clk);



	free_irq(i2c_dev->irq, i2c_dev);

	i2c_del_adapter(&i2c_dev->adapter);

drivers/i2c/i2c-core-base.c

+10 −3
Original line number Diff line number Diff line
@@ -186,10 +186,11 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap) 
	 * If we can set SDA, we will always create a STOP to ensure additional

	 * pulses will do no harm. This is achieved by letting SDA follow SCL

	 * half a cycle later. Check the 'incomplete_write_byte' fault injector

	 * for details.

	 * for details. Note that we must honour tsu:sto, 4us, but lets use 5us

	 * here for simplicity.

	 */

	bri->set_scl(adap, scl);

	ndelay(RECOVERY_NDELAY / 2);

	ndelay(RECOVERY_NDELAY);

	if (bri->set_sda)

		bri->set_sda(adap, scl);

	ndelay(RECOVERY_NDELAY / 2);
@@ -211,7 +212,13 @@ int i2c_generic_scl_recovery(struct i2c_adapter *adap) 
		scl = !scl;

		bri->set_scl(adap, scl);

		/* Creating STOP again, see above */

		if (scl)  {

			/* Honour minimum tsu:sto */

			ndelay(RECOVERY_NDELAY);

		} else {

			/* Honour minimum tf and thd:dat */

			ndelay(RECOVERY_NDELAY / 2);

		}

		if (bri->set_sda)

			bri->set_sda(adap, scl);

		ndelay(RECOVERY_NDELAY / 2);

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