staging:iio:adc:ad799x use a table for frequency values rather than big switch.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/adc/ad799x_core.c

@@ -169,7 +169,15 @@ static int ad799x_read_raw(struct iio_dev *dev_info,
 	}
 	return -EINVAL;
 }
-
+static const unsigned int ad7998_frequencies[] = {
+	[AD7998_CYC_DIS]	= 0,
+	[AD7998_CYC_TCONF_32]	= 15625,
+	[AD7998_CYC_TCONF_64]	= 7812,
+	[AD7998_CYC_TCONF_128]	= 3906,
+	[AD7998_CYC_TCONF_512]	= 976,
+	[AD7998_CYC_TCONF_1024]	= 488,
+	[AD7998_CYC_TCONF_2048]	= 244,
+};
 static ssize_t ad799x_read_frequency(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
@@ -177,7 +185,7 @@ static ssize_t ad799x_read_frequency(struct device *dev,
 	struct iio_dev *dev_info = dev_get_drvdata(dev);
 	struct ad799x_state *st = iio_priv(dev_info);
 
-	int ret, len = 0;
+	int ret;
 	u8 val;
 	ret = ad799x_i2c_read8(st, AD7998_CYCLE_TMR_REG, &val);
 	if (ret)
@@ -185,33 +193,7 @@ static ssize_t ad799x_read_frequency(struct device *dev,
 
 	val &= AD7998_CYC_MASK;
 
-	switch (val) {
-	case AD7998_CYC_DIS:
-		len = sprintf(buf, "0\n");
-		break;
-	case AD7998_CYC_TCONF_32:
-		len = sprintf(buf, "15625\n");
-		break;
-	case AD7998_CYC_TCONF_64:
-		len = sprintf(buf, "7812\n");
-		break;
-	case AD7998_CYC_TCONF_128:
-		len = sprintf(buf, "3906\n");
-		break;
-	case AD7998_CYC_TCONF_256:
-		len = sprintf(buf, "1953\n");
-		break;
-	case AD7998_CYC_TCONF_512:
-		len = sprintf(buf, "976\n");
-		break;
-	case AD7998_CYC_TCONF_1024:
-		len = sprintf(buf, "488\n");
-		break;
-	case AD7998_CYC_TCONF_2048:
-		len = sprintf(buf, "244\n");
-		break;
-	}
-	return len;
+	return sprintf(buf, "%u\n", ad7998_frequencies[val]);
 }
 
 static ssize_t ad799x_write_frequency(struct device *dev,
@@ -223,7 +205,7 @@ static ssize_t ad799x_write_frequency(struct device *dev,
 	struct ad799x_state *st = iio_priv(dev_info);
 
 	long val;
-	int ret;
+	int ret, i;
 	u8 t;
 
 	ret = strict_strtol(buf, 10, &val);
@@ -237,36 +219,14 @@ static ssize_t ad799x_write_frequency(struct device *dev,
 	/* Wipe the bits clean */
 	t &= ~AD7998_CYC_MASK;
 
-	switch (val) {
-	case 15625:
-		t |= AD7998_CYC_TCONF_32;
-		break;
-	case 7812:
-		t |= AD7998_CYC_TCONF_64;
-		break;
-	case 3906:
-		t |= AD7998_CYC_TCONF_128;
-		break;
-	case 1953:
-		t |= AD7998_CYC_TCONF_256;
-		break;
-	case 976:
-		t |= AD7998_CYC_TCONF_512;
-		break;
-	case 488:
-		t |= AD7998_CYC_TCONF_1024;
+	for (i = 0; i < ARRAY_SIZE(ad7998_frequencies); i++)
+		if (val == ad7998_frequencies[i])
 			break;
-	case 244:
-		t |= AD7998_CYC_TCONF_2048;
-		break;
-	case  0:
-		t |= AD7998_CYC_DIS;
-		break;
-	default:
+	if (i == ARRAY_SIZE(ad7998_frequencies)) {
 		ret = -EINVAL;
 		goto error_ret_mutex;
 	}
-
+	t |= i;
 	ret = ad799x_i2c_write8(st, AD7998_CYCLE_TMR_REG, t);
 
 error_ret_mutex: