Staging: panel: Replace NULL comparison.

Use ! operating instead of NULL checks.
Addresses "CHECK: Comparison to NULL" from checkpatch.pl.
Signed-off-by: NAybuke Ozdemir <aybuke.147@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/panel/panel.c

@@ -920,7 +920,7 @@ static void lcd_gotoxy(void)
 static void lcd_print(char c)
 {
 	if (lcd.addr.x < lcd.bwidth) {
-		if (lcd_char_conv != NULL)
+		if (lcd_char_conv)
 			c = lcd_char_conv[(unsigned char)c];
 		lcd_write_data(c);
 		lcd.addr.x++;
@@ -1118,7 +1118,7 @@ static inline int handle_lcd_special_code(void)
 		break;
 	case '*':
 		/* flash back light using the keypad timer */
-		if (scan_timer.function != NULL) {
+		if (scan_timer.function) {
 			if (lcd.light_tempo == 0
 					&& ((lcd.flags & LCD_FLAG_L) == 0))
 				lcd_backlight(1);
@@ -1200,7 +1200,7 @@ static inline int handle_lcd_special_code(void)
 		char value;
 		int addr;
 
-		if (strchr(esc, ';') == NULL)
+		if (!strchr(esc, ';'))
 			break;
 
 		esc++;
@@ -1246,7 +1246,7 @@ static inline int handle_lcd_special_code(void)
 	}
 	case 'x':	/* gotoxy : LxXXX[yYYY]; */
 	case 'y':	/* gotoxy : LyYYY[xXXX]; */
-		if (strchr(esc, ';') == NULL)
+		if (!strchr(esc, ';'))
 			break;
 
 		while (*esc) {
@@ -1844,7 +1844,7 @@ static inline int input_state_high(struct logical_input *input)
 		if ((input->type == INPUT_TYPE_STD) &&
 		    (input->high_timer == 0)) {
 			input->high_timer++;
-			if (input->u.std.press_fct != NULL)
+			if (input->u.std.press_fct)
 				input->u.std.press_fct(input->u.std.press_data);
 		} else if (input->type == INPUT_TYPE_KBD) {
 			/* will turn on the light */
@@ -1924,7 +1924,7 @@ static inline void input_state_falling(struct logical_input *input)
 		if (input->type == INPUT_TYPE_STD) {
 			void (*release_fct)(int) = input->u.std.release_fct;
 
-			if (release_fct != NULL)
+			if (release_fct)
 				release_fct(input->u.std.release_data);
 		} else if (input->type == INPUT_TYPE_KBD) {
 			char *release_str = input->u.kbd.release_str;
@@ -2025,7 +2025,7 @@ static void panel_scan_timer(void)
 
 static void init_scan_timer(void)
 {
-	if (scan_timer.function != NULL)
+	if (scan_timer.function)
 		return;		/* already started */
 
 	setup_timer(&scan_timer, (void *)&panel_scan_timer, 0);
@@ -2229,7 +2229,7 @@ static void panel_attach(struct parport *port)
 	/* panel_cb.flags = 0 should be PARPORT_DEV_EXCL? */
 
 	pprt = parport_register_dev_model(port, "panel", &panel_cb, 0);
-	if (pprt == NULL) {
+	if (!pprt) {
 		pr_err("%s: port->number=%d parport=%d, parport_register_device() failed\n",
 		       __func__, port->number, parport);
 		return;
@@ -2276,10 +2276,10 @@ static void panel_detach(struct parport *port)
 		       __func__, port->number, parport);
 		return;
 	}
-	if (scan_timer.function != NULL)
+	if (scan_timer.function)
 		del_timer_sync(&scan_timer);
 
-	if (pprt != NULL) {
+	if (pprt) {
 		if (keypad.enabled) {
 			misc_deregister(&keypad_dev);
 			keypad_initialized = 0;