misc: panel, convert struct to bitmap

There is an anonymous struct which is actually used as a bitmap. So
convert the struct to a bitmap and change code accordingly where
needed.

This also allows for a cleanup of set_data_bits and set_ctrl_bits as
they can use a common helper now. The helper can also be converted to
a for loop instead of doing bit OR. And given it is a for loop now,
bit masking (using BIT_MSK) is moved from the callers there too.

Signed-off-by: Daniel Chromik <daniel.chromik@seznam.cz>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Acked-by: Willy Tarreau <willy@haproxy.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/panel.c b/drivers/misc/panel.c
index 4262db0237f90e46b02f08a3f5505f5d18af953f..6030ac5b8c63919018da1ad3b2e8957ae881636d 100644 (file)
--- a/drivers/misc/panel.c
+++ b/drivers/misc/panel.c
@@ -648,34 +648,28 @@ static const char nexcom_keypad_profile[][4][9] = {
 
 static const char (*keypad_profile)[4][9] = old_keypad_profile;
 
-/* FIXME: this should be converted to a bit array containing signals states */
-static struct {
-       unsigned char e;  /* parallel LCD E (data latch on falling edge) */
-       unsigned char rs; /* parallel LCD RS  (0 = cmd, 1 = data) */
-       unsigned char rw; /* parallel LCD R/W (0 = W, 1 = R) */
-       unsigned char bl; /* parallel LCD backlight (0 = off, 1 = on) */
-       unsigned char cl; /* serial LCD clock (latch on rising edge) */
-       unsigned char da; /* serial LCD data */
-} bits;
+static DECLARE_BITMAP(bits, LCD_BITS);
+
+static void lcd_get_bits(unsigned int port, int *val)
+{
+       unsigned int bit, state;
+
+       for (bit = 0; bit < LCD_BITS; bit++) {
+               state = test_bit(bit, bits) ? BIT_SET : BIT_CLR;
+               *val &= lcd_bits[port][bit][BIT_MSK];
+               *val |= lcd_bits[port][bit][state];
+       }
+}
 
 static void init_scan_timer(void);
 
 /* sets data port bits according to current signals values */
 static int set_data_bits(void)
 {
-       int val, bit;
+       int val;
 
        val = r_dtr(pprt);
-       for (bit = 0; bit < LCD_BITS; bit++)
-               val &= lcd_bits[LCD_PORT_D][bit][BIT_MSK];
-
-       val |= lcd_bits[LCD_PORT_D][LCD_BIT_E][bits.e]
-           | lcd_bits[LCD_PORT_D][LCD_BIT_RS][bits.rs]
-           | lcd_bits[LCD_PORT_D][LCD_BIT_RW][bits.rw]
-           | lcd_bits[LCD_PORT_D][LCD_BIT_BL][bits.bl]
-           | lcd_bits[LCD_PORT_D][LCD_BIT_CL][bits.cl]
-           | lcd_bits[LCD_PORT_D][LCD_BIT_DA][bits.da];
-
+       lcd_get_bits(LCD_PORT_D, &val);
        w_dtr(pprt, val);
        return val;
 }
@@ -683,19 +677,10 @@ static int set_data_bits(void)
 /* sets ctrl port bits according to current signals values */
 static int set_ctrl_bits(void)
 {
-       int val, bit;
+       int val;
 
        val = r_ctr(pprt);
-       for (bit = 0; bit < LCD_BITS; bit++)
-               val &= lcd_bits[LCD_PORT_C][bit][BIT_MSK];
-
-       val |= lcd_bits[LCD_PORT_C][LCD_BIT_E][bits.e]
-           | lcd_bits[LCD_PORT_C][LCD_BIT_RS][bits.rs]
-           | lcd_bits[LCD_PORT_C][LCD_BIT_RW][bits.rw]
-           | lcd_bits[LCD_PORT_C][LCD_BIT_BL][bits.bl]
-           | lcd_bits[LCD_PORT_C][LCD_BIT_CL][bits.cl]
-           | lcd_bits[LCD_PORT_C][LCD_BIT_DA][bits.da];
-
+       lcd_get_bits(LCD_PORT_C, &val);
        w_ctr(pprt, val);
        return val;
 }
@@ -791,12 +776,17 @@ static void lcd_send_serial(int byte)
         * LCD reads D0 on STROBE's rising edge.
         */
        for (bit = 0; bit < 8; bit++) {
-               bits.cl = BIT_CLR;      /* CLK low */
+               clear_bit(LCD_BIT_CL, bits);    /* CLK low */
                panel_set_bits();
-               bits.da = byte & 1;
+               if (byte & 1) {
+                       set_bit(LCD_BIT_DA, bits);
+               } else {
+                       clear_bit(LCD_BIT_DA, bits);
+               }
+
                panel_set_bits();
                udelay(2);  /* maintain the data during 2 us before CLK up */
-               bits.cl = BIT_SET;      /* CLK high */
+               set_bit(LCD_BIT_CL, bits);      /* CLK high */
                panel_set_bits();
                udelay(1);  /* maintain the strobe during 1 us */
                byte >>= 1;
@@ -811,7 +801,10 @@ static void lcd_backlight(int on)
 
        /* The backlight is activated by setting the AUTOFEED line to +5V  */
        spin_lock_irq(&pprt_lock);
-       bits.bl = on;
+       if (on)
+               set_bit(LCD_BIT_BL, bits);
+       else
+               clear_bit(LCD_BIT_BL, bits);
        panel_set_bits();
        spin_unlock_irq(&pprt_lock);
 }
@@ -846,14 +839,14 @@ static void lcd_write_cmd_p8(int cmd)
        w_dtr(pprt, cmd);
        udelay(20);     /* maintain the data during 20 us before the strobe */
 
-       bits.e = BIT_SET;
-       bits.rs = BIT_CLR;
-       bits.rw = BIT_CLR;
+       set_bit(LCD_BIT_E, bits);
+       clear_bit(LCD_BIT_RS, bits);
+       clear_bit(LCD_BIT_RW, bits);
        set_ctrl_bits();
 
        udelay(40);     /* maintain the strobe during 40 us */
 
-       bits.e = BIT_CLR;
+       clear_bit(LCD_BIT_E, bits);
        set_ctrl_bits();
 
        udelay(120);    /* the shortest command takes at least 120 us */
@@ -868,14 +861,14 @@ static void lcd_write_data_p8(int data)
        w_dtr(pprt, data);
        udelay(20);     /* maintain the data during 20 us before the strobe */
 
-       bits.e = BIT_SET;
-       bits.rs = BIT_SET;
-       bits.rw = BIT_CLR;
+       set_bit(LCD_BIT_E, bits);
+       set_bit(LCD_BIT_RS, bits);
+       clear_bit(LCD_BIT_RW, bits);
        set_ctrl_bits();
 
        udelay(40);     /* maintain the strobe during 40 us */
 
-       bits.e = BIT_CLR;
+       clear_bit(LCD_BIT_E, bits);
        set_ctrl_bits();
 
        udelay(45);     /* the shortest data takes at least 45 us */
@@ -968,15 +961,15 @@ static void lcd_clear_fast_p8(void)
                /* maintain the data during 20 us before the strobe */
                udelay(20);
 
-               bits.e = BIT_SET;
-               bits.rs = BIT_SET;
-               bits.rw = BIT_CLR;
+               set_bit(LCD_BIT_E, bits);
+               set_bit(LCD_BIT_RS, bits);
+               clear_bit(LCD_BIT_RW, bits);
                set_ctrl_bits();
 
                /* maintain the strobe during 40 us */
                udelay(40);
 
-               bits.e = BIT_CLR;
+               clear_bit(LCD_BIT_E, bits);
                set_ctrl_bits();
 
                /* the shortest data takes at least 45 us */