Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ebd10e07 authored by Virupax Sadashivpetimath's avatar Virupax Sadashivpetimath Committed by Ben Dooks
Browse files

i2c-nomadik: add code to retry on timeout failure 



It is seen that i2c-nomadik controller randomly stops generating the
interrupts leading to a i2c timeout. As a workaround to this problem,
add retries to the on going transfer on failure.

Signed-off-by: default avatarVirupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
Reviewed-by: default avatarJonas ABERG <jonas.aberg@stericsson.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarBen Dooks <ben-linux@fluff.org>
parent b0e751a9

drivers/i2c/busses/i2c-nomadik.c

+49 −48
Original line number Diff line number Diff line
@@ -255,8 +255,6 @@ static int init_hw(struct nmk_i2c_dev *dev) 
{

	int stat;



	clk_enable(dev->clk);



	stat = flush_i2c_fifo(dev);

	if (stat)

		goto exit;
@@ -271,8 +269,6 @@ static int init_hw(struct nmk_i2c_dev *dev) 
	dev->cli.operation = I2C_NO_OPERATION;



exit:

	/* TODO: Why disable clocks after init hw? */

	clk_disable(dev->clk);

	/*

	 * TODO: What is this delay for?

	 * Must be pretty pointless since the hw block
@@ -572,6 +568,7 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, 
	u32 cause;

	struct nmk_i2c_dev *dev = i2c_get_adapdata(i2c_adap);

	u32 i2c_sr;

	int j;



	dev->busy = true;
@@ -579,12 +576,13 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, 
		regulator_enable(dev->regulator);

	pm_runtime_get_sync(&dev->pdev->dev);



	clk_enable(dev->clk);



	status = init_hw(dev);

	if (status)

		goto out2;



	clk_enable(dev->clk);

		goto out;



	for (j = 0; j < 3; j++) {

		/* setup the i2c controller */

		setup_i2c_controller(dev);
@@ -614,28 +612,31 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap, 
			if (status || (dev->result)) {

				i2c_sr = readl(dev->virtbase + I2C_SR);

				/*

			 * Check if the controller I2C operation status is set

			 * to ABORT(11b).

				 * Check if the controller I2C operation status

				 * is set to ABORT(11b).

				 */

				if (((i2c_sr >> 2) & 0x3) == 0x3) {

					/* get the abort cause */

					cause =	(i2c_sr >> 4)

						& 0x7;

				dev_err(&dev->pdev->dev, "%s\n", cause >=

						ARRAY_SIZE(abort_causes) ?

					dev_err(&dev->pdev->dev, "%s\n", cause

						>= ARRAY_SIZE(abort_causes) ?

						"unknown reason" :

						abort_causes[cause]);

				}



				status = status ? status : dev->result;

			goto out;



				break;

			}

			udelay(I2C_DELAY);

		}

		if (status == 0)

			break;

	}



out:

	clk_disable(dev->clk);

out2:

	pm_runtime_put_sync(&dev->pdev->dev);

	if (dev->regulator)

		regulator_disable(dev->regulator);