X-Git-Url: https://git.kernelconcepts.de/?a=blobdiff_plain;f=drivers%2Fi2c%2Fmxs_i2c.c;h=de3b19402b4af1c2f8a97283a77a0d92d034b0ed;hb=f7582ce8496f19edf845d1f62c4b7f385e4cd864;hp=b907f7b379bb6c6bb02aabffdff363f4560bc23c;hpb=a098cf41fdb2a6607c675f7fe4f3164617c9367e;p=karo-tx-uboot.git

diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c
index b907f7b379..de3b19402b 100644
--- a/drivers/i2c/mxs_i2c.c
+++ b/drivers/i2c/mxs_i2c.c
@@ -10,20 +10,7 @@
  * Which was based on a (non-working) driver which was:
  * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- *
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 #include <common.h>
@@ -37,7 +24,7 @@
 
 #define	MXS_I2C_MAX_TIMEOUT	1000000
 
-void mxs_i2c_reset(void)
+static void mxs_i2c_reset(void)
 {
 	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
 	int ret;
@@ -59,7 +46,7 @@ void mxs_i2c_reset(void)
 	i2c_set_bus_speed(speed);
 }
 
-void mxs_i2c_setup_read(uint8_t chip, int len)
+static void mxs_i2c_setup_read(uint8_t chip, int len)
 {
 	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
 
@@ -77,16 +64,17 @@ void mxs_i2c_setup_read(uint8_t chip, int len)
 	writel(I2C_QUEUECTRL_QUEUE_RUN, &i2c_regs->hw_i2c_queuectrl_set);
 }
 
-void mxs_i2c_write(uchar chip, uint addr, int alen,
+static int mxs_i2c_write(uchar chip, uint addr, int alen,
 			uchar *buf, int blen, int stop)
 {
 	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
-	uint32_t data;
+	uint32_t data, tmp;
 	int i, remain, off;
+	int timeout = MXS_I2C_MAX_TIMEOUT;
 
 	if ((alen > 4) || (alen == 0)) {
 		debug("MXS I2C: Invalid address length\n");
-		return;
+		return -EINVAL;
 	}
 
 	if (stop)
@@ -119,9 +107,22 @@ void mxs_i2c_write(uchar chip, uint addr, int alen,
 		writel(data >> remain, &i2c_regs->hw_i2c_data);
 
 	writel(I2C_QUEUECTRL_QUEUE_RUN, &i2c_regs->hw_i2c_queuectrl_set);
+
+	while (--timeout) {
+		tmp = readl(&i2c_regs->hw_i2c_queuestat);
+		if (tmp & I2C_QUEUESTAT_WR_QUEUE_EMPTY)
+			break;
+	}
+
+	if (!timeout) {
+		debug("MXS I2C: Failed transmitting data!\n");
+		return -EINVAL;
+	}
+
+	return 0;
 }
 
-int mxs_i2c_wait_for_ack(void)
+static int mxs_i2c_wait_for_ack(void)
 {
 	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
 	uint32_t tmp;
@@ -163,10 +164,16 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
 {
 	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
 	uint32_t tmp = 0;
+	int timeout = MXS_I2C_MAX_TIMEOUT;
 	int ret;
 	int i;
 
-	mxs_i2c_write(chip, addr, alen, NULL, 0, 0);
+	ret = mxs_i2c_write(chip, addr, alen, NULL, 0, 0);
+	if (ret) {
+		debug("MXS I2C: Failed writing address\n");
+		return ret;
+	}
+
 	ret = mxs_i2c_wait_for_ack();
 	if (ret) {
 		debug("MXS I2C: Failed writing address\n");
@@ -182,9 +189,17 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
 
 	for (i = 0; i < len; i++) {
 		if (!(i & 3)) {
-			while (readl(&i2c_regs->hw_i2c_queuestat) &
-				I2C_QUEUESTAT_RD_QUEUE_EMPTY)
-				;
+			while (--timeout) {
+				tmp = readl(&i2c_regs->hw_i2c_queuestat);
+				if (!(tmp & I2C_QUEUESTAT_RD_QUEUE_EMPTY))
+					break;
+			}
+
+			if (!timeout) {
+				debug("MXS I2C: Failed receiving data!\n");
+				return -ETIMEDOUT;
+			}
+
 			tmp = readl(&i2c_regs->hw_i2c_queuedata);
 		}
 		buffer[i] = tmp & 0xff;
@@ -197,7 +212,12 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
 {
 	int ret;
-	mxs_i2c_write(chip, addr, alen, buffer, len, 1);
+	ret = mxs_i2c_write(chip, addr, alen, buffer, len, 1);
+	if (ret) {
+		debug("MXS I2C: Failed writing address\n");
+		return ret;
+	}
+
 	ret = mxs_i2c_wait_for_ack();
 	if (ret)
 		debug("MXS I2C: Failed writing address\n");
@@ -208,8 +228,9 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
 int i2c_probe(uchar chip)
 {
 	int ret;
-	mxs_i2c_write(chip, 0, 1, NULL, 0, 1);
-	ret = mxs_i2c_wait_for_ack();
+	ret = mxs_i2c_write(chip, 0, 1, NULL, 0, 1);
+	if (!ret)
+		ret = mxs_i2c_wait_for_ack();
 	mxs_i2c_reset();
 	return ret;
 }