Input: nomadik-ske-keypad - add multi key press support

Added the multi key press support for SKE keypad by modifying the irq
function for handling the two different keys on the same column and also
pressing the two different keys of different columns on the same ASR
register.

Signed-off-by: Naveen Kumar Gaddipati <[e-mail]>
Reviewed-by: Srinidhi Kasagar <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/keyboard/nomadik-ske-keypad.c

···
 	return 0;
 }
 
+static void ske_keypad_report(struct ske_keypad *keypad, u8 status, int col)
+{
+	int row = 0, code, pos;
+	struct input_dev *input = keypad->input;
+	u32 ske_ris;
+	int key_pressed;
+	int num_of_rows;
+
+	/* find out the row */
+	num_of_rows = hweight8(status);
+	do {
+		pos = __ffs(status);
+		row = pos;
+		status &= ~(1 << pos);
+
+		code = MATRIX_SCAN_CODE(row, col, SKE_KEYPAD_ROW_SHIFT);
+		ske_ris = readl(keypad->reg_base + SKE_RIS);
+		key_pressed = ske_ris & SKE_KPRISA;
+
+		input_event(input, EV_MSC, MSC_SCAN, code);
+		input_report_key(input, keypad->keymap[code], key_pressed);
+		input_sync(input);
+		num_of_rows--;
+	} while (num_of_rows);
+}
+
 static void ske_keypad_read_data(struct ske_keypad *keypad)
 {
-	struct input_dev *input = keypad->input;
-	u16 status;
-	int col = 0, row = 0, code;
-	int ske_asr, ske_ris, key_pressed, i;
+	u8 status;
+	int col = 0;
+	int ske_asr, i;
 
 	/*
 	 * Read the auto scan registers
···
 		if (!ske_asr)
 			continue;
 
-		/* now that ASRx is zero, find out the column x and row y*/
-		if (ske_asr & 0xff) {
+		/* now that ASRx is zero, find out the coloumn x and row y */
+		status = ske_asr & 0xff;
+		if (status) {
 			col = i * 2;
-			status = ske_asr & 0xff;
-		} else {
-			col = (i * 2) + 1;
-			status = (ske_asr & 0xff00) >> 8;
+			ske_keypad_report(keypad, status, col);
 		}
-
-		/* find out the row */
-		row = __ffs(status);
-
-		code = MATRIX_SCAN_CODE(row, col, SKE_KEYPAD_ROW_SHIFT);
-		ske_ris = readl(keypad->reg_base + SKE_RIS);
-		key_pressed = ske_ris & SKE_KPRISA;
-
-		input_event(input, EV_MSC, MSC_SCAN, code);
-		input_report_key(input, keypad->keymap[code], key_pressed);
-		input_sync(input);
+		status = (ske_asr & 0xff00) >> 8;
+		if (status) {
+			col = (i * 2) + 1;
+			ske_keypad_report(keypad, status, col);
+		}
 	}
 }
 
···
 	ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA);
 
 	while ((readl(keypad->reg_base + SKE_CR) & SKE_KPASON) && --retries)
-		msleep(5);
+		cpu_relax();
 
-	if (retries) {
-		/* SKEx registers are stable and can be read */
-		ske_keypad_read_data(keypad);
-	}
+	/* SKEx registers are stable and can be read */
+	ske_keypad_read_data(keypad);
 
 	/* enable auto scan interrupts */
 	ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);