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[PATCH] auxdisplay: ht16k33: use le16_to_cpup() to fetch LE16 data

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The data read from the device is 3 little-endian words, so let's annotate
them as such and use le16_to_cpu() to convert them to host endianness - it
might turn out to be a bit more performant, and it expresses the conversion
more clearly.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/auxdisplay/ht16k33.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/auxdisplay/ht16k33.c b/drivers/auxdisplay/ht16k33.c
index f66b45b235b0..61af52a7afd5 100644
--- a/drivers/auxdisplay/ht16k33.c
+++ b/drivers/auxdisplay/ht16k33.c
@@ -254,18 +254,19 @@ static bool ht16k33_keypad_scan(struct ht16k33_keypad *keypad)
 {
 	const unsigned short *keycodes = keypad->dev->keycode;
 	u16 new_state[HT16K33_MATRIX_KEYPAD_MAX_COLS];
-	u8 data[HT16K33_MATRIX_KEYPAD_MAX_COLS * 2];
+	__le16 data[HT16K33_MATRIX_KEYPAD_MAX_COLS];
 	unsigned long bits_changed;
 	int row, col, code;
 	bool pressed = false;
 
-	if (i2c_smbus_read_i2c_block_data(keypad->client, 0x40, 6, data) != 6) {
+	if (i2c_smbus_read_i2c_block_data(keypad->client, 0x40,
+					  sizeof(data), (u8 *)data) != 6) {
 		dev_err(&keypad->client->dev, "Failed to read key data\n");
 		return false;
 	}
 
 	for (col = 0; col < keypad->cols; col++) {
-		new_state[col] = (data[col * 2 + 1] << 8) | data[col * 2];
+		new_state[col] = le16_to_cpu(data[col]);
 		if (new_state[col])
 			pressed = true;
 		bits_changed = keypad->last_key_state[col] ^ new_state[col];
-- 
2.12.2.564.g063fe858b8-goog


-- 
Dmitry

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[PATCH] auxdisplay: ht16k33: use le16_to_cpup() to fetch LE16 data Dmitry Torokhov <dmitry.torokhov@gmail.com> - 2017-03-29 09:50 +0200
  Re: [PATCH] auxdisplay: ht16k33: use le16_to_cpup() to fetch LE16  data Robin van der Gracht <robin@protonic.nl> - 2017-03-29 10:20 +0200
    Re: [PATCH] auxdisplay: ht16k33: use le16_to_cpup() to fetch LE16  data Dmitry Torokhov <dmitry.torokhov@gmail.com> - 2017-04-01 19:30 +0200

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