[PATCH v2 9/9] staging: panel: Move LCD-related state into struct lcd

Mariusz Gorski
2014-11-19T20:47:36Z

Move more or less all LCD-related state into struct lcd
in order to get better cohesion; use bool instead of int
where it makes sense.

Signed-off-by: Mariusz Gorski <marius.gorski@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
---
drivers/staging/panel/panel.c | 255 ++++++++++++++++++++++--------------------
1 file changed, 134 insertions(+), 121 deletions(-)

diff --git a/drivers/staging/panel/panel.c b/drivers/staging/panel/panel.c
index 19f6767..98325b7 100644
--- a/drivers/staging/panel/panel.c
+++ b/drivers/staging/panel/panel.c
@@ -225,12 +225,20 @@ static wait_queue_head_t keypad_read_wait;
/* lcd-specific variables */
static struct {
bool enabled;
+ bool initialized;
+ bool must_clear;
+
+ /* TODO: use bool here? */
+ char left_shift;
+
int height;
int width;
int bwidth;
int hwidth;
int charset;
int proto;
+ int light_tempo;
+
/* TODO: use union here? */
struct {
int e;
@@ -240,22 +248,26 @@ static struct {
int da;
int bl;
} pins;
+
+ /* contains the LCD config state */
+ unsigned long int flags;
+
+ /* Contains the LCD X and Y offset */
+ struct {
+ unsigned long int x;
+ unsigned long int y;
+ } addr;
+
+ /* Current escape sequence and it's length or -1 if outside */
+ struct {
+ char buf[LCD_ESCAPE_LEN + 1];
+ int len;
+ } esc_seq;
} lcd;

/* Needed only for init */
static int selected_lcd_type = NOT_SET;

-/* contains the LCD config state */
-static unsigned long int lcd_flags;
-/* contains the LCD X offset */
-static unsigned long int lcd_addr_x;
-/* contains the LCD Y offset */
-static unsigned long int lcd_addr_y;
-/* current escape sequence, 0 terminated */
-static char lcd_escape[LCD_ESCAPE_LEN + 1];
-/* not in escape state. >=0 = escape cmd len */
-static int lcd_escape_len = -1;
-
/*
* Bit masks to convert LCD signals to parallel port outputs.
* _d_ are values for data port, _c_ are for control port.
@@ -438,13 +450,8 @@ static atomic_t keypad_available = ATOMIC_INIT(1);

static struct pardevice *pprt;

-static int lcd_initialized;
static int keypad_initialized;

-static int light_tempo;
-
-static char lcd_must_clear;
-static char lcd_left_shift;
static char init_in_progress;

static void (*lcd_write_cmd)(int);
@@ -880,23 +887,23 @@ static void lcd_write_data_tilcd(int data)
static void lcd_gotoxy(void)
{
lcd_write_cmd(0x80 /* set DDRAM address */
- | (lcd_addr_y ? lcd.hwidth : 0)
+ | (lcd.addr.y ? lcd.hwidth : 0)
/* we force the cursor to stay at the end of the
line if it wants to go farther */
- | ((lcd_addr_x < lcd.bwidth) ? lcd_addr_x &
+ | ((lcd.addr.x < lcd.bwidth) ? lcd.addr.x &
(lcd.hwidth - 1) : lcd.bwidth - 1));
}

static void lcd_print(char c)
{
- if (lcd_addr_x < lcd.bwidth) {
+ if (lcd.addr.x < lcd.bwidth) {
if (lcd_char_conv != NULL)
c = lcd_char_conv[(unsigned char)c];
lcd_write_data(c);
- lcd_addr_x++;
+ lcd.addr.x++;
}
/* prevents the cursor from wrapping onto the next line */
- if (lcd_addr_x == lcd.bwidth)
+ if (lcd.addr.x == lcd.bwidth)
lcd_gotoxy();
}

@@ -905,8 +912,8 @@ static void lcd_clear_fast_s(void)
{
int pos;

- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();

spin_lock_irq(&pprt_lock);
@@ -918,8 +925,8 @@ static void lcd_clear_fast_s(void)
}
spin_unlock_irq(&pprt_lock);

- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();
}

@@ -928,8 +935,8 @@ static void lcd_clear_fast_p8(void)
{
int pos;

- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();

spin_lock_irq(&pprt_lock);
@@ -956,8 +963,8 @@ static void lcd_clear_fast_p8(void)
}
spin_unlock_irq(&pprt_lock);

- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();
}

@@ -966,8 +973,8 @@ static void lcd_clear_fast_tilcd(void)
{
int pos;

- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();

spin_lock_irq(&pprt_lock);
@@ -979,8 +986,8 @@ static void lcd_clear_fast_tilcd(void)

spin_unlock_irq(&pprt_lock);

- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();
}

@@ -988,15 +995,15 @@ static void lcd_clear_fast_tilcd(void)
static void lcd_clear_display(void)
{
lcd_write_cmd(0x01); /* clear display */
- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
/* we must wait a few milliseconds (15) */
long_sleep(15);
}

static void lcd_init_display(void)
{
- lcd_flags = ((lcd.height > 1) ? LCD_FLAG_N : 0)
+ lcd.flags = ((lcd.height > 1) ? LCD_FLAG_N : 0)
| LCD_FLAG_D | LCD_FLAG_C | LCD_FLAG_B;

long_sleep(20); /* wait 20 ms after power-up for the paranoid */
@@ -1009,8 +1016,8 @@ static void lcd_init_display(void)
long_sleep(10);

lcd_write_cmd(0x30 /* set font height and lines number */
- | ((lcd_flags & LCD_FLAG_F) ? 4 : 0)
- | ((lcd_flags & LCD_FLAG_N) ? 8 : 0)
+ | ((lcd.flags & LCD_FLAG_F) ? 4 : 0)
+ | ((lcd.flags & LCD_FLAG_N) ? 8 : 0)
);
long_sleep(10);

@@ -1018,12 +1025,12 @@ static void lcd_init_display(void)
long_sleep(10);

lcd_write_cmd(0x08 /* set display mode */
- | ((lcd_flags & LCD_FLAG_D) ? 4 : 0)
- | ((lcd_flags & LCD_FLAG_C) ? 2 : 0)
- | ((lcd_flags & LCD_FLAG_B) ? 1 : 0)
+ | ((lcd.flags & LCD_FLAG_D) ? 4 : 0)
+ | ((lcd.flags & LCD_FLAG_C) ? 2 : 0)
+ | ((lcd.flags & LCD_FLAG_B) ? 1 : 0)
);

- lcd_backlight((lcd_flags & LCD_FLAG_L) ? 1 : 0);
+ lcd_backlight((lcd.flags & LCD_FLAG_L) ? 1 : 0);

long_sleep(10);

@@ -1046,100 +1053,101 @@ static inline int handle_lcd_special_code(void)

int processed = 0;

- char *esc = lcd_escape + 2;
- int oldflags = lcd_flags;
+ char *esc = lcd.esc_seq.buf + 2;
+ int oldflags = lcd.flags;

/* check for display mode flags */
switch (*esc) {
case 'D': /* Display ON */
- lcd_flags |= LCD_FLAG_D;
+ lcd.flags |= LCD_FLAG_D;
processed = 1;
break;
case 'd': /* Display OFF */
- lcd_flags &= ~LCD_FLAG_D;
+ lcd.flags &= ~LCD_FLAG_D;
processed = 1;
break;
case 'C': /* Cursor ON */
- lcd_flags |= LCD_FLAG_C;
+ lcd.flags |= LCD_FLAG_C;
processed = 1;
break;
case 'c': /* Cursor OFF */
- lcd_flags &= ~LCD_FLAG_C;
+ lcd.flags &= ~LCD_FLAG_C;
processed = 1;
break;
case 'B': /* Blink ON */
- lcd_flags |= LCD_FLAG_B;
+ lcd.flags |= LCD_FLAG_B;
processed = 1;
break;
case 'b': /* Blink OFF */
- lcd_flags &= ~LCD_FLAG_B;
+ lcd.flags &= ~LCD_FLAG_B;
processed = 1;
break;
case '+': /* Back light ON */
- lcd_flags |= LCD_FLAG_L;
+ lcd.flags |= LCD_FLAG_L;
processed = 1;
break;
case '-': /* Back light OFF */
- lcd_flags &= ~LCD_FLAG_L;
+ lcd.flags &= ~LCD_FLAG_L;
processed = 1;
break;
case '*':
/* flash back light using the keypad timer */
if (scan_timer.function != NULL) {
- if (light_tempo == 0 && ((lcd_flags & LCD_FLAG_L) == 0))
+ if (lcd.light_tempo == 0
+ && ((lcd.flags & LCD_FLAG_L) == 0))
lcd_backlight(1);
- light_tempo = FLASH_LIGHT_TEMPO;
+ lcd.light_tempo = FLASH_LIGHT_TEMPO;
}
processed = 1;
break;
case 'f': /* Small Font */
- lcd_flags &= ~LCD_FLAG_F;
+ lcd.flags &= ~LCD_FLAG_F;
processed = 1;
break;
case 'F': /* Large Font */
- lcd_flags |= LCD_FLAG_F;
+ lcd.flags |= LCD_FLAG_F;
processed = 1;
break;
case 'n': /* One Line */
- lcd_flags &= ~LCD_FLAG_N;
+ lcd.flags &= ~LCD_FLAG_N;
processed = 1;
break;
case 'N': /* Two Lines */
- lcd_flags |= LCD_FLAG_N;
+ lcd.flags |= LCD_FLAG_N;
break;
case 'l': /* Shift Cursor Left */
- if (lcd_addr_x > 0) {
+ if (lcd.addr.x > 0) {
/* back one char if not at end of line */
- if (lcd_addr_x < lcd.bwidth)
+ if (lcd.addr.x < lcd.bwidth)
lcd_write_cmd(0x10);
- lcd_addr_x--;
+ lcd.addr.x--;
}
processed = 1;
break;
case 'r': /* shift cursor right */
- if (lcd_addr_x < lcd.width) {
+ if (lcd.addr.x < lcd.width) {
/* allow the cursor to pass the end of the line */
- if (lcd_addr_x <
+ if (lcd.addr.x <
(lcd.bwidth - 1))
lcd_write_cmd(0x14);
- lcd_addr_x++;
+ lcd.addr.x++;
}
processed = 1;
break;
case 'L': /* shift display left */
- lcd_left_shift++;
+ lcd.left_shift++;
lcd_write_cmd(0x18);
processed = 1;
break;
case 'R': /* shift display right */
- lcd_left_shift--;
+ lcd.left_shift--;
lcd_write_cmd(0x1C);
processed = 1;
break;
case 'k': { /* kill end of line */
int x;

- for (x = lcd_addr_x; x < lcd.bwidth; x++)
+ for (x = lcd.addr.x; x < lcd.bwidth; x++)
lcd_write_data(' ');

/* restore cursor position */
@@ -1149,7 +1157,7 @@ static inline int handle_lcd_special_code(void)
}
case 'I': /* reinitialize display */
lcd_init_display();
- lcd_left_shift = 0;
+ lcd.left_shift = 0;
processed = 1;
break;
case 'G': {
@@ -1220,11 +1228,11 @@ static inline int handle_lcd_special_code(void)
while (*esc) {
if (*esc == 'x') {
esc++;
- if (kstrtoul(esc, 10, &lcd_addr_x) < 0)
+ if (kstrtoul(esc, 10, &lcd.addr.x) < 0)
break;
} else if (*esc == 'y') {
esc++;
- if (kstrtoul(esc, 10, &lcd_addr_y) < 0)
+ if (kstrtoul(esc, 10, &lcd.addr.y) < 0)
break;
} else {
break;
@@ -1237,25 +1245,25 @@ static inline int handle_lcd_special_code(void)
}

/* Check whether one flag was changed */
- if (oldflags != lcd_flags) {
+ if (oldflags != lcd.flags) {
/* check whether one of B,C,D flags were changed */
- if ((oldflags ^ lcd_flags) &
+ if ((oldflags ^ lcd.flags) &
(LCD_FLAG_B | LCD_FLAG_C | LCD_FLAG_D))
/* set display mode */
lcd_write_cmd(0x08
- | ((lcd_flags & LCD_FLAG_D) ? 4 : 0)
- | ((lcd_flags & LCD_FLAG_C) ? 2 : 0)
- | ((lcd_flags & LCD_FLAG_B) ? 1 : 0));
+ | ((lcd.flags & LCD_FLAG_D) ? 4 : 0)
+ | ((lcd.flags & LCD_FLAG_C) ? 2 : 0)
+ | ((lcd.flags & LCD_FLAG_B) ? 1 : 0));
/* check whether one of F,N flags was changed */
- else if ((oldflags ^ lcd_flags) & (LCD_FLAG_F | LCD_FLAG_N))
+ else if ((oldflags ^ lcd.flags) & (LCD_FLAG_F | LCD_FLAG_N))
lcd_write_cmd(0x30
- | ((lcd_flags & LCD_FLAG_F) ? 4 : 0)
- | ((lcd_flags & LCD_FLAG_N) ? 8 : 0));
+ | ((lcd.flags & LCD_FLAG_F) ? 4 : 0)
+ | ((lcd.flags & LCD_FLAG_N) ? 8 : 0));
/* check whether L flag was changed */
- else if ((oldflags ^ lcd_flags) & (LCD_FLAG_L)) {
- if (lcd_flags & (LCD_FLAG_L))
+ else if ((oldflags ^ lcd.flags) & (LCD_FLAG_L)) {
+ if (lcd.flags & (LCD_FLAG_L))
lcd_backlight(1);
- else if (light_tempo == 0)
+ else if (lcd.light_tempo == 0)
/* switch off the light only when the tempo
lighting is gone */
lcd_backlight(0);
@@ -1268,29 +1276,29 @@ static inline int handle_lcd_special_code(void)
static void lcd_write_char(char c)
{
/* first, we'll test if we're in escape mode */
- if ((c != '\n') && lcd_escape_len >= 0) {
+ if ((c != '\n') && lcd.esc_seq.len >= 0) {
/* yes, let's add this char to the buffer */
- lcd_escape[lcd_escape_len++] = c;
- lcd_escape[lcd_escape_len] = 0;
+ lcd.esc_seq.buf[lcd.esc_seq.len++] = c;
+ lcd.esc_seq.buf[lcd.esc_seq.len] = 0;
} else {
/* aborts any previous escape sequence */
- lcd_escape_len = -1;
+ lcd.esc_seq.len = -1;

switch (c) {
case LCD_ESCAPE_CHAR:
/* start of an escape sequence */
- lcd_escape_len = 0;
- lcd_escape[lcd_escape_len] = 0;
+ lcd.esc_seq.len = 0;
+ lcd.esc_seq.buf[lcd.esc_seq.len] = 0;
break;
case '\b':
/* go back one char and clear it */
- if (lcd_addr_x > 0) {
+ if (lcd.addr.x > 0) {
/* check if we're not at the
end of the line */
- if (lcd_addr_x < lcd.bwidth)
+ if (lcd.addr.x < lcd.bwidth)
/* back one char */
lcd_write_cmd(0x10);
- lcd_addr_x--;
+ lcd.addr.x--;
}
/* replace with a space */
lcd_write_data(' ');
@@ -1304,15 +1312,15 @@ static void lcd_write_char(char c)
case '\n':
/* flush the remainder of the current line and
go to the beginning of the next line */
- for (; lcd_addr_x < lcd.bwidth; lcd_addr_x++)
+ for (; lcd.addr.x < lcd.bwidth; lcd.addr.x++)
lcd_write_data(' ');
- lcd_addr_x = 0;
- lcd_addr_y = (lcd_addr_y + 1) % lcd.height;
+ lcd.addr.x = 0;
+ lcd.addr.y = (lcd.addr.y + 1) % lcd.height;
lcd_gotoxy();
break;
case '\r':
/* go to the beginning of the same line */
- lcd_addr_x = 0;
+ lcd.addr.x = 0;
lcd_gotoxy();
break;
case '\t':
@@ -1328,32 +1336,32 @@ static void lcd_write_char(char c)

/* now we'll see if we're in an escape mode and if the current
escape sequence can be understood. */
- if (lcd_escape_len >= 2) {
+ if (lcd.esc_seq.len >= 2) {
int processed = 0;

- if (!strcmp(lcd_escape, "[2J")) {
+ if (!strcmp(lcd.esc_seq.buf, "[2J")) {
/* clear the display */
lcd_clear_fast();
processed = 1;
- } else if (!strcmp(lcd_escape, "[H")) {
+ } else if (!strcmp(lcd.esc_seq.buf, "[H")) {
/* cursor to home */
- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
lcd_gotoxy();
processed = 1;
}
/* codes starting with ^[[L */
- else if ((lcd_escape_len >= 3) &&
- (lcd_escape[0] == '[') &&
- (lcd_escape[1] == 'L')) {
+ else if ((lcd.esc_seq.len >= 3) &&
+ (lcd.esc_seq.buf[0] == '[') &&
+ (lcd.esc_seq.buf[1] == 'L')) {
processed = handle_lcd_special_code();
}

/* LCD special escape codes */
/* flush the escape sequence if it's been processed
or if it is getting too long. */
- if (processed || (lcd_escape_len >= LCD_ESCAPE_LEN))
- lcd_escape_len = -1;
+ if (processed || (lcd.esc_seq.len >= LCD_ESCAPE_LEN))
+ lcd.esc_seq.len = -1;
} /* escape codes */
}

@@ -1386,9 +1394,9 @@ static int lcd_open(struct inode *inode, struct file *file)
if (file->f_mode & FMODE_READ) /* device is write-only */
return -EPERM;

- if (lcd_must_clear) {
+ if (lcd.must_clear) {
lcd_clear_display();
- lcd_must_clear = 0;
+ lcd.must_clear = false;
}
return nonseekable_open(inode, file);
}
@@ -1418,7 +1426,7 @@ static void panel_lcd_print(const char *s)
const char *tmp = s;
int count = strlen(s);

- if (lcd.enabled && lcd_initialized) {
+ if (lcd.enabled && lcd.initialized) {
for (; count-- > 0; tmp++) {
if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
/* let's be a little nice with other processes
@@ -1599,7 +1607,7 @@ static void lcd_init(void)
/* before this line, we must NOT send anything to the display.
* Since lcd_init_display() needs to write data, we have to
* enable mark the LCD initialized just before. */
- lcd_initialized = 1;
+ lcd.initialized = true;
lcd_init_display();

/* display a short message */
@@ -1611,10 +1619,10 @@ static void lcd_init(void)
panel_lcd_print("\x1b[Lc\x1b[Lb\x1b[L*Linux-" UTS_RELEASE "\nPanel-"
PANEL_VERSION);
#endif
- lcd_addr_x = 0;
- lcd_addr_y = 0;
+ lcd.addr.x = 0;
+ lcd.addr.y = 0;
/* clear the display on the next device opening */
- lcd_must_clear = 1;
+ lcd.must_clear = true;
lcd_gotoxy();
}

@@ -1950,14 +1958,16 @@ static void panel_scan_timer(void)
panel_process_inputs();
}

- if (lcd.enabled && lcd_initialized) {
+ if (lcd.enabled && lcd.initialized) {
if (keypressed) {
- if (light_tempo == 0 && ((lcd_flags & LCD_FLAG_L) == 0))
+ if (lcd.light_tempo == 0
+ && ((lcd.flags & LCD_FLAG_L) == 0))
lcd_backlight(1);
- light_tempo = FLASH_LIGHT_TEMPO;
- } else if (light_tempo > 0) {
- light_tempo--;
- if (light_tempo == 0 && ((lcd_flags & LCD_FLAG_L) == 0))
+ lcd.light_tempo = FLASH_LIGHT_TEMPO;
+ } else if (lcd.light_tempo > 0) {
+ lcd.light_tempo--;
+ if (lcd.light_tempo == 0
+ && ((lcd.flags & LCD_FLAG_L) == 0))
lcd_backlight(0);
}
}
@@ -2129,7 +2139,7 @@ static void keypad_init(void)
static int panel_notify_sys(struct notifier_block *this, unsigned long code,
void *unused)
{
- if (lcd.enabled && lcd_initialized) {
+ if (lcd.enabled && lcd.initialized) {
switch (code) {
case SYS_DOWN:
panel_lcd_print
@@ -2222,9 +2232,9 @@ static void panel_detach(struct parport *port)
keypad_initialized = 0;
}

- if (lcd.enabled && lcd_initialized) {
+ if (lcd.enabled && lcd.initialized) {
misc_deregister(&lcd_dev);
- lcd_initialized = 0;
+ lcd.initialized = false;
}

parport_release(pprt);
@@ -2300,6 +2310,9 @@ static int __init panel_init_module(void)
lcd.pins.da = lcd_da_pin;
lcd.pins.bl = lcd_bl_pin;

+ /* Leave it for now, just in case */
+ lcd.esc_seq.len = -1;
+
/*
* Overwrite selection with module param values (both keypad and lcd),
* where the deprecated params have lower prio.
@@ -2385,7 +2398,7 @@ static void __exit panel_cleanup_module(void)
panel_lcd_print("\x0cLCD driver " PANEL_VERSION
"\nunloaded.\x1b[Lc\x1b[Lb\x1b[L-");
misc_deregister(&lcd_dev);
- lcd_initialized = 0;
+ lcd.initialized = false;
}

/* TODO: free all input signals */
--
2.1.3