Commit 18854296 authored by Carlos Song's avatar Carlos Song Committed by Andi Shyti
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i2c: imx-lpi2c: add generic GPIO recovery for LPI2C 



This adds i2c bus recovery to the lpi2c driver.

Uses the generic recovery function setting the SCL/SDA pads as
GPIO pins and sending 9 clocks to try and recover the bus.

Signed-off-by: default avatarCarlos Song <carlos.song@nxp.com>
Reviewed-by: default avatarClark Wang <xiaoning.wang@nxp.com>
Reviewed-by: default avatarDong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: default avatarAndi Shyti <andi.shyti@kernel.org>
parent 747bdf91

drivers/i2c/busses/i2c-imx-lpi2c.c

+27 −0
Original line number Diff line number Diff line
@@ -106,6 +106,7 @@ struct lpi2c_imx_struct { 
	unsigned int		txfifosize;

	unsigned int		rxfifosize;

	enum lpi2c_imx_mode	mode;

	struct i2c_bus_recovery_info rinfo;

};



static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,
@@ -133,6 +134,8 @@ static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx) 


		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {

			dev_dbg(&lpi2c_imx->adapter.dev, "bus not work\n");

			if (lpi2c_imx->adapter.bus_recovery_info)

				i2c_recover_bus(&lpi2c_imx->adapter);

			return -ETIMEDOUT;

		}

		schedule();
@@ -190,6 +193,8 @@ static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx) 


		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {

			dev_dbg(&lpi2c_imx->adapter.dev, "stop timeout\n");

			if (lpi2c_imx->adapter.bus_recovery_info)

				i2c_recover_bus(&lpi2c_imx->adapter);

			break;

		}

		schedule();
@@ -325,6 +330,8 @@ static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx) 


		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {

			dev_dbg(&lpi2c_imx->adapter.dev, "txfifo empty timeout\n");

			if (lpi2c_imx->adapter.bus_recovery_info)

				i2c_recover_bus(&lpi2c_imx->adapter);

			return -ETIMEDOUT;

		}

		schedule();
@@ -526,6 +533,20 @@ static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id) 
	return IRQ_HANDLED;

}



static int lpi2c_imx_init_recovery_info(struct lpi2c_imx_struct *lpi2c_imx,

				  struct platform_device *pdev)

{

	struct i2c_bus_recovery_info *bri = &lpi2c_imx->rinfo;



	bri->pinctrl = devm_pinctrl_get(&pdev->dev);

	if (IS_ERR(bri->pinctrl))

		return PTR_ERR(bri->pinctrl);



	lpi2c_imx->adapter.bus_recovery_info = bri;



	return 0;

}



static u32 lpi2c_imx_func(struct i2c_adapter *adapter)

{

	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
@@ -600,6 +621,12 @@ static int lpi2c_imx_probe(struct platform_device *pdev) 
	lpi2c_imx->txfifosize = 1 << (temp & 0x0f);

	lpi2c_imx->rxfifosize = 1 << ((temp >> 8) & 0x0f);



	/* Init optional bus recovery function */

	ret = lpi2c_imx_init_recovery_info(lpi2c_imx, pdev);

	/* Give it another chance if pinctrl used is not ready yet */

	if (ret == -EPROBE_DEFER)

		goto rpm_disable;



	ret = i2c_add_adapter(&lpi2c_imx->adapter);

	if (ret)

		goto rpm_disable;