Commit 8336f9de authored by Emanuele Ghidoli's avatar Emanuele Ghidoli Committed by Andi Shyti
Browse files

i2c: lpi2c: use readl_poll_timeout() for register polling 



Replaces polling loops with the readl_poll_timeout() helper macro.

Signed-off-by: default avatarEmanuele Ghidoli <emanuele.ghidoli@toradex.com>
Signed-off-by: default avatarFrancesco Dolcini <francesco.dolcini@toradex.com>
Reviewed-by: default avatarCarlos Song <carlos.song@nxp.com>
Tested-by: default avatarPrimoz Fiser <primoz.fiser@norik.com>
Signed-off-by: default avatarAndi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250718133429.67219-2-francesco@dolcini.it
parent f8fd855d

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

+45 −49
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <linux/init.h>

#include <linux/interrupt.h>

#include <linux/io.h>

#include <linux/iopoll.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/of.h>
@@ -187,6 +188,10 @@ struct lpi2c_imx_struct { 
	struct i2c_client	*target;

};



#define lpi2c_imx_read_msr_poll_timeout(val, cond)                            \

		  readl_poll_timeout(lpi2c_imx->base + LPI2C_MSR, val, cond,  \

				     0, 500000)



static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx,

			      unsigned int enable)

{
@@ -195,11 +200,11 @@ static void lpi2c_imx_intctrl(struct lpi2c_imx_struct *lpi2c_imx, 


static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx)

{

	unsigned long orig_jiffies = jiffies;

	unsigned int temp;

	int err;



	while (1) {

		temp = readl(lpi2c_imx->base + LPI2C_MSR);

	err = lpi2c_imx_read_msr_poll_timeout(temp,

					      temp & (MSR_ALF | MSR_BBF | MSR_MBF));



	/* check for arbitration lost, clear if set */

	if (temp & MSR_ALF) {
@@ -207,21 +212,22 @@ static int lpi2c_imx_bus_busy(struct lpi2c_imx_struct *lpi2c_imx) 
		return -EAGAIN;

	}



		if (temp & (MSR_BBF | MSR_MBF))

			break;



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

	/* check for bus not busy */

	if (err) {

		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();

	}



	return 0;

}



static u32 lpi2c_imx_txfifo_cnt(struct lpi2c_imx_struct *lpi2c_imx)

{

	return readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;

}



static void lpi2c_imx_set_mode(struct lpi2c_imx_struct *lpi2c_imx)

{

	unsigned int bitrate = lpi2c_imx->bitrate;
@@ -259,25 +265,18 @@ static int lpi2c_imx_start(struct lpi2c_imx_struct *lpi2c_imx, 


static void lpi2c_imx_stop(struct lpi2c_imx_struct *lpi2c_imx)

{

	unsigned long orig_jiffies = jiffies;

	unsigned int temp;

	int err;



	writel(GEN_STOP << 8, lpi2c_imx->base + LPI2C_MTDR);



	do {

		temp = readl(lpi2c_imx->base + LPI2C_MSR);

		if (temp & MSR_SDF)

			break;

	err = lpi2c_imx_read_msr_poll_timeout(temp, temp & MSR_SDF);



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

	if (err) {

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

		if (lpi2c_imx->adapter.bus_recovery_info)

			i2c_recover_bus(&lpi2c_imx->adapter);

			break;

	}

		schedule();



	} while (1);

}



/* CLKLO = I2C_CLK_RATIO * CLKHI, SETHOLD = CLKHI, DATAVD = CLKHI/2 */
@@ -393,26 +392,23 @@ static int lpi2c_imx_pio_msg_complete(struct lpi2c_imx_struct *lpi2c_imx) 


static int lpi2c_imx_txfifo_empty(struct lpi2c_imx_struct *lpi2c_imx)

{

	unsigned long orig_jiffies = jiffies;

	u32 txcnt;

	unsigned int temp;

	int err;



	do {

		txcnt = readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff;

	err = lpi2c_imx_read_msr_poll_timeout(temp,

					      (temp & MSR_NDF) || !lpi2c_imx_txfifo_cnt(lpi2c_imx));



		if (readl(lpi2c_imx->base + LPI2C_MSR) & MSR_NDF) {

	if (temp & MSR_NDF) {

		dev_dbg(&lpi2c_imx->adapter.dev, "NDF detected\n");

		return -EIO;

	}



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

	if (err) {

		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();



	} while (txcnt);



	return 0;

}