2 files changed, 29 insertions, 14 deletions

diff --git a/drivers/i2c/algos/i2c-algo-pca.c b/drivers/i2c/algos/i2c-algo-pca.c
index 710fbef9a9c2..384af88e58ad 100644
--- a/drivers/i2c/algos/i2c-algo-pca.c
+++ b/drivers/i2c/algos/i2c-algo-pca.c
@@ -41,8 +41,22 @@ static void pca_reset(struct i2c_algo_pca_data *adap)
 		pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_IPRESET);
 		pca_outw(adap, I2C_PCA_IND, 0xA5);
 		pca_outw(adap, I2C_PCA_IND, 0x5A);
+
+		/*
+		 * After a reset we need to re-apply any configuration
+		 * (calculated in pca_init) to get the bus in a working state.
+		 */
+		pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_IMODE);
+		pca_outw(adap, I2C_PCA_IND, adap->bus_settings.mode);
+		pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_ISCLL);
+		pca_outw(adap, I2C_PCA_IND, adap->bus_settings.tlow);
+		pca_outw(adap, I2C_PCA_INDPTR, I2C_PCA_ISCLH);
+		pca_outw(adap, I2C_PCA_IND, adap->bus_settings.thi);
+
+		pca_set_con(adap, I2C_PCA_CON_ENSIO);
 	} else {
 		adap->reset_chip(adap->data);
+		pca_set_con(adap, I2C_PCA_CON_ENSIO | adap->bus_settings.clock_freq);
 	}
 }
 
@@ -423,13 +437,14 @@ static int pca_init(struct i2c_adapter *adap)
 				" Use the nominal frequency.\n", adap->name);
 		}
 
-		pca_reset(pca_data);
-
 		clock = pca_clock(pca_data);
 		printk(KERN_INFO "%s: Clock frequency is %dkHz\n",
 		     adap->name, freqs[clock]);
 
-		pca_set_con(pca_data, I2C_PCA_CON_ENSIO | clock);
+		/* Store settings as these will be needed when the PCA chip is reset */
+		pca_data->bus_settings.clock_freq = clock;
+
+		pca_reset(pca_data);
 	} else {
 		int clock;
 		int mode;
@@ -496,19 +511,15 @@ static int pca_init(struct i2c_adapter *adap)
 			thi = tlow * min_thi / min_tlow;
 		}
 
+		/* Store settings as these will be needed when the PCA chip is reset */
+		pca_data->bus_settings.mode = mode;
+		pca_data->bus_settings.tlow = tlow;
+		pca_data->bus_settings.thi = thi;
+
 		pca_reset(pca_data);
 
 		printk(KERN_INFO
 		     "%s: Clock frequency is %dHz\n", adap->name, clock * 100);
-
-		pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_IMODE);
-		pca_outw(pca_data, I2C_PCA_IND, mode);
-		pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_ISCLL);
-		pca_outw(pca_data, I2C_PCA_IND, tlow);
-		pca_outw(pca_data, I2C_PCA_INDPTR, I2C_PCA_ISCLH);
-		pca_outw(pca_data, I2C_PCA_IND, thi);
-
-		pca_set_con(pca_data, I2C_PCA_CON_ENSIO);
 	}
 	udelay(500); /* 500 us for oscillator to stabilise */
 
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 75f07138a6fa..dfcf04e1967f 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -2093,8 +2093,12 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 		}
 	}
 
-	/* Adaptive TimeOut: astimated time in usec + 100% margin */
-	timeout_usec = (2 * 10000 / bus->bus_freq) * (2 + nread + nwrite);
+	/*
+	 * Adaptive TimeOut: estimated time in usec + 100% margin:
+	 * 2: double the timeout for clock stretching case
+	 * 9: bits per transaction (including the ack/nack)
+	 */
+	timeout_usec = (2 * 9 * USEC_PER_SEC / bus->bus_freq) * (2 + nread + nwrite);
 	timeout = max(msecs_to_jiffies(35), usecs_to_jiffies(timeout_usec));
 	if (nwrite >= 32 * 1024 || nread >= 32 * 1024) {
 		dev_err(bus->dev, "i2c%d buffer too big\n", bus->num);