[linux-block.git] / drivers / auxdisplay / hd44780_common.c

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>

#include "charlcd.h"
#include "hd44780_common.h"

/* LCD commands */
#define LCD_CMD_DISPLAY_CLEAR	0x01	/* Clear entire display */

#define LCD_CMD_ENTRY_MODE	0x04	/* Set entry mode */
#define LCD_CMD_CURSOR_INC	0x02	/* Increment cursor */

#define LCD_CMD_DISPLAY_CTRL	0x08	/* Display control */
#define LCD_CMD_DISPLAY_ON	0x04	/* Set display on */
#define LCD_CMD_CURSOR_ON	0x02	/* Set cursor on */
#define LCD_CMD_BLINK_ON	0x01	/* Set blink on */

#define LCD_CMD_SHIFT		0x10	/* Shift cursor/display */
#define LCD_CMD_DISPLAY_SHIFT	0x08	/* Shift display instead of cursor */
#define LCD_CMD_SHIFT_RIGHT	0x04	/* Shift display/cursor to the right */

#define LCD_CMD_FUNCTION_SET	0x20	/* Set function */
#define LCD_CMD_DATA_LEN_8BITS	0x10	/* Set data length to 8 bits */
#define LCD_CMD_TWO_LINES	0x08	/* Set to two display lines */
#define LCD_CMD_FONT_5X10_DOTS	0x04	/* Set char font to 5x10 dots */

#define LCD_CMD_SET_CGRAM_ADDR	0x40	/* Set char generator RAM address */

#define LCD_CMD_SET_DDRAM_ADDR	0x80	/* Set display data RAM address */

/* sleeps that many milliseconds with a reschedule */
static void long_sleep(int ms)
{
	schedule_timeout_interruptible(msecs_to_jiffies(ms));
}

int hd44780_common_print(struct charlcd *lcd, int c)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (lcd->addr.x < hdc->bwidth) {
		hdc->write_data(hdc, c);
		return 0;
	}

	return 1;
}
EXPORT_SYMBOL_GPL(hd44780_common_print);

int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
{
	struct hd44780_common *hdc = lcd->drvdata;
	unsigned int addr;

	/*
	 * we force the cursor to stay at the end of the
	 * line if it wants to go farther
	 */
	addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1;
	if (y & 1)
		addr += hdc->hwidth;
	if (y & 2)
		addr += hdc->bwidth;
	hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR | addr);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_gotoxy);

int hd44780_common_home(struct charlcd *lcd)
{
	return hd44780_common_gotoxy(lcd, 0, 0);
}
EXPORT_SYMBOL_GPL(hd44780_common_home);

/* clears the display and resets X/Y */
int hd44780_common_clear_display(struct charlcd *lcd)
{
	struct hd44780_common *hdc = lcd->drvdata;

	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);
	/* datasheet says to wait 1,64 milliseconds */
	long_sleep(2);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_clear_display);

int hd44780_common_init_display(struct charlcd *lcd)
{
	struct hd44780_common *hdc = lcd->drvdata;

	void (*write_cmd_raw)(struct hd44780_common *hdc, int cmd);
	u8 init;

	if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
		return -EINVAL;

	hdc->hd44780_common_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 */

	/*
	 * 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
	 * the LCD is in 8-bit mode afterwards
	 */
	init = LCD_CMD_FUNCTION_SET | LCD_CMD_DATA_LEN_8BITS;
	if (hdc->ifwidth == 4) {
		init >>= 4;
		write_cmd_raw = hdc->write_cmd_raw4;
	} else {
		write_cmd_raw = hdc->write_cmd;
	}
	write_cmd_raw(hdc, init);
	long_sleep(10);
	write_cmd_raw(hdc, init);
	long_sleep(10);
	write_cmd_raw(hdc, init);
	long_sleep(10);

	if (hdc->ifwidth == 4) {
		/* Switch to 4-bit mode, 1 line, small fonts */
		hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
		long_sleep(10);
	}

	/* set font height and lines number */
	hdc->write_cmd(hdc,
		LCD_CMD_FUNCTION_SET |
		((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_F) ?
			LCD_CMD_FONT_5X10_DOTS : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_N) ?
			LCD_CMD_TWO_LINES : 0));
	long_sleep(10);

	/* display off, cursor off, blink off */
	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
	long_sleep(10);

	hdc->write_cmd(hdc,
		LCD_CMD_DISPLAY_CTRL |	/* set display mode */
		((hdc->hd44780_common_flags & LCD_FLAG_D) ?
			LCD_CMD_DISPLAY_ON : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_C) ?
			LCD_CMD_CURSOR_ON : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_B) ?
			LCD_CMD_BLINK_ON : 0));

	charlcd_backlight(lcd,
			(hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);

	long_sleep(10);

	/* entry mode set : increment, cursor shifting */
	hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE | LCD_CMD_CURSOR_INC);

	hd44780_common_clear_display(lcd);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_init_display);

int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (dir == CHARLCD_SHIFT_LEFT) {
		/* back one char if not at end of line */
		if (lcd->addr.x < hdc->bwidth)
			hdc->write_cmd(hdc, LCD_CMD_SHIFT);
	} else if (dir == CHARLCD_SHIFT_RIGHT) {
		/* allow the cursor to pass the end of the line */
		if (lcd->addr.x < (hdc->bwidth - 1))
			hdc->write_cmd(hdc,
					LCD_CMD_SHIFT | LCD_CMD_SHIFT_RIGHT);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);

int hd44780_common_shift_display(struct charlcd *lcd,
		enum charlcd_shift_dir dir)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (dir == CHARLCD_SHIFT_LEFT)
		hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT);
	else if (dir == CHARLCD_SHIFT_RIGHT)
		hdc->write_cmd(hdc, LCD_CMD_SHIFT | LCD_CMD_DISPLAY_SHIFT |
			LCD_CMD_SHIFT_RIGHT);

	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_shift_display);

static void hd44780_common_set_mode(struct hd44780_common *hdc)
{
	hdc->write_cmd(hdc,
		LCD_CMD_DISPLAY_CTRL |
		((hdc->hd44780_common_flags & LCD_FLAG_D) ?
			LCD_CMD_DISPLAY_ON : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_C) ?
			LCD_CMD_CURSOR_ON : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_B) ?
			LCD_CMD_BLINK_ON : 0));
}

int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (on == CHARLCD_ON)
		hdc->hd44780_common_flags |= LCD_FLAG_D;
	else
		hdc->hd44780_common_flags &= ~LCD_FLAG_D;

	hd44780_common_set_mode(hdc);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_display);

int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (on == CHARLCD_ON)
		hdc->hd44780_common_flags |= LCD_FLAG_C;
	else
		hdc->hd44780_common_flags &= ~LCD_FLAG_C;

	hd44780_common_set_mode(hdc);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_cursor);

int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (on == CHARLCD_ON)
		hdc->hd44780_common_flags |= LCD_FLAG_B;
	else
		hdc->hd44780_common_flags &= ~LCD_FLAG_B;

	hd44780_common_set_mode(hdc);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_blink);

static void hd44780_common_set_function(struct hd44780_common *hdc)
{
	hdc->write_cmd(hdc,
		LCD_CMD_FUNCTION_SET |
		((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_F) ?
			LCD_CMD_FONT_5X10_DOTS : 0) |
		((hdc->hd44780_common_flags & LCD_FLAG_N) ?
			LCD_CMD_TWO_LINES : 0));
}

int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (size == CHARLCD_FONTSIZE_LARGE)
		hdc->hd44780_common_flags |= LCD_FLAG_F;
	else
		hdc->hd44780_common_flags &= ~LCD_FLAG_F;

	hd44780_common_set_function(hdc);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_fontsize);

int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines)
{
	struct hd44780_common *hdc = lcd->drvdata;

	if (lines == CHARLCD_LINES_2)
		hdc->hd44780_common_flags |= LCD_FLAG_N;
	else
		hdc->hd44780_common_flags &= ~LCD_FLAG_N;

	hd44780_common_set_function(hdc);
	return 0;
}
EXPORT_SYMBOL_GPL(hd44780_common_lines);

int hd44780_common_redefine_char(struct charlcd *lcd, char *esc)
{
	/* Generator : LGcxxxxx...xx; must have <c> between '0'
	 * and '7', representing the numerical ASCII code of the
	 * redefined character, and <xx...xx> a sequence of 16
	 * hex digits representing 8 bytes for each character.
	 * Most LCDs will only use 5 lower bits of the 7 first
	 * bytes.
	 */

	struct hd44780_common *hdc = lcd->drvdata;
	unsigned char cgbytes[8];
	unsigned char cgaddr;
	int cgoffset;
	int shift;
	char value;
	int addr;

	if (!strchr(esc, ';'))
		return 0;

	esc++;

	cgaddr = *(esc++) - '0';
	if (cgaddr > 7)
		return 1;

	cgoffset = 0;
	shift = 0;
	value = 0;
	while (*esc && cgoffset < 8) {
		int half;

		shift ^= 4;
		half = hex_to_bin(*esc++);
		if (half < 0)
			continue;

		value |= half << shift;
		if (shift == 0) {
			cgbytes[cgoffset++] = value;
			value = 0;
		}
	}

	hdc->write_cmd(hdc, LCD_CMD_SET_CGRAM_ADDR | (cgaddr * 8));
	for (addr = 0; addr < cgoffset; addr++)
		hdc->write_data(hdc, cgbytes[addr]);

	/* ensures that we stop writing to CGRAM */
	lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
	return 1;
}
EXPORT_SYMBOL_GPL(hd44780_common_redefine_char);

struct hd44780_common *hd44780_common_alloc(void)
{
	struct hd44780_common *hd;

	hd = kzalloc(sizeof(*hd), GFP_KERNEL);
	if (!hd)
		return NULL;

	hd->ifwidth = 8;
	hd->bwidth = DEFAULT_LCD_BWIDTH;
	hd->hwidth = DEFAULT_LCD_HWIDTH;
	return hd;
}
EXPORT_SYMBOL_GPL(hd44780_common_alloc);

MODULE_LICENSE("GPL");
Commit	Line	Data
718e05ed LP	1	// SPDX-License-Identifier: GPL-2.0-or-later
718e05ed LP	2	#include <linux/module.h>
45421ffe	3	#include <linux/sched.h>
718e05ed LP	4	#include <linux/slab.h>
718e05ed LP	5
b26deabb	6	#include "charlcd.h"
718e05ed LP	7	#include "hd44780_common.h"
718e05ed LP	8
d3a2fb81	9	/* LCD commands */
45421ffe LP	10	#define LCD_CMD_DISPLAY_CLEAR 0x01 /* Clear entire display */
45421ffe LP	11
01ec46df LP	12	#define LCD_CMD_ENTRY_MODE 0x04 /* Set entry mode */
	13	#define LCD_CMD_CURSOR_INC 0x02 /* Increment cursor */
	14
	15	#define LCD_CMD_DISPLAY_CTRL 0x08 /* Display control */
	16	#define LCD_CMD_DISPLAY_ON 0x04 /* Set display on */
	17	#define LCD_CMD_CURSOR_ON 0x02 /* Set cursor on */
	18	#define LCD_CMD_BLINK_ON 0x01 /* Set blink on */
	19
d2f2187e LP	20	#define LCD_CMD_SHIFT 0x10 /* Shift cursor/display */
	21	#define LCD_CMD_DISPLAY_SHIFT 0x08 /* Shift display instead of cursor */
	22	#define LCD_CMD_SHIFT_RIGHT 0x04 /* Shift display/cursor to the right */
	23
01ec46df LP	24	#define LCD_CMD_FUNCTION_SET 0x20 /* Set function */
	25	#define LCD_CMD_DATA_LEN_8BITS 0x10 /* Set data length to 8 bits */
	26	#define LCD_CMD_TWO_LINES 0x08 /* Set to two display lines */
	27	#define LCD_CMD_FONT_5X10_DOTS 0x04 /* Set char font to 5x10 dots */
	28
339acb08 LP	29	#define LCD_CMD_SET_CGRAM_ADDR 0x40 /* Set char generator RAM address */
339acb08 LP	30
d3a2fb81 LP	31	#define LCD_CMD_SET_DDRAM_ADDR 0x80 /* Set display data RAM address */
d3a2fb81 LP	32
45421ffe LP	33	/* sleeps that many milliseconds with a reschedule */
	34	static void long_sleep(int ms)
	35	{
	36	schedule_timeout_interruptible(msecs_to_jiffies(ms));
	37	}
	38
b26deabb LP	39	int hd44780_common_print(struct charlcd *lcd, int c)
	40	{
	41	struct hd44780_common *hdc = lcd->drvdata;
	42
	43	if (lcd->addr.x < hdc->bwidth) {
	44	hdc->write_data(hdc, c);
	45	return 0;
	46	}
	47
	48	return 1;
	49	}
	50	EXPORT_SYMBOL_GPL(hd44780_common_print);
	51
40c2b72e	52	int hd44780_common_gotoxy(struct charlcd *lcd, unsigned int x, unsigned int y)
d3a2fb81 LP	53	{
	54	struct hd44780_common *hdc = lcd->drvdata;
	55	unsigned int addr;
	56
	57	/*
	58	* we force the cursor to stay at the end of the
	59	* line if it wants to go farther
	60	*/
40c2b72e LP	61	addr = x < hdc->bwidth ? x & (hdc->hwidth - 1) : hdc->bwidth - 1;
40c2b72e LP	62	if (y & 1)
d3a2fb81	63	addr += hdc->hwidth;
40c2b72e	64	if (y & 2)
d3a2fb81 LP	65	addr += hdc->bwidth;
	66	hdc->write_cmd(hdc, LCD_CMD_SET_DDRAM_ADDR \| addr);
	67	return 0;
	68	}
	69	EXPORT_SYMBOL_GPL(hd44780_common_gotoxy);
	70
88645a86 LP	71	int hd44780_common_home(struct charlcd *lcd)
88645a86 LP	72	{
40c2b72e	73	return hd44780_common_gotoxy(lcd, 0, 0);
88645a86 LP	74	}
	75	EXPORT_SYMBOL_GPL(hd44780_common_home);
	76
45421ffe LP	77	/* clears the display and resets X/Y */
	78	int hd44780_common_clear_display(struct charlcd *lcd)
	79	{
	80	struct hd44780_common *hdc = lcd->drvdata;
	81
	82	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CLEAR);
7b231bb5 LP	83	/* datasheet says to wait 1,64 milliseconds */
7b231bb5 LP	84	long_sleep(2);
45421ffe LP	85	return 0;
	86	}
	87	EXPORT_SYMBOL_GPL(hd44780_common_clear_display);
	88
01ec46df LP	89	int hd44780_common_init_display(struct charlcd *lcd)
	90	{
	91	struct hd44780_common *hdc = lcd->drvdata;
	92
	93	void (write_cmd_raw)(struct hd44780_common hdc, int cmd);
	94	u8 init;
	95
	96	if (hdc->ifwidth != 4 && hdc->ifwidth != 8)
	97	return -EINVAL;
	98
	99	hdc->hd44780_common_flags = ((lcd->height > 1) ? LCD_FLAG_N : 0) \|
	100	LCD_FLAG_D \| LCD_FLAG_C \| LCD_FLAG_B;
	101
	102	long_sleep(20); /* wait 20 ms after power-up for the paranoid */
	103
	104	/*
	105	* 8-bit mode, 1 line, small fonts; let's do it 3 times, to make sure
	106	* the LCD is in 8-bit mode afterwards
	107	*/
	108	init = LCD_CMD_FUNCTION_SET \| LCD_CMD_DATA_LEN_8BITS;
	109	if (hdc->ifwidth == 4) {
	110	init >>= 4;
	111	write_cmd_raw = hdc->write_cmd_raw4;
	112	} else {
	113	write_cmd_raw = hdc->write_cmd;
	114	}
	115	write_cmd_raw(hdc, init);
	116	long_sleep(10);
	117	write_cmd_raw(hdc, init);
	118	long_sleep(10);
	119	write_cmd_raw(hdc, init);
	120	long_sleep(10);
	121
	122	if (hdc->ifwidth == 4) {
	123	/* Switch to 4-bit mode, 1 line, small fonts */
	124	hdc->write_cmd_raw4(hdc, LCD_CMD_FUNCTION_SET >> 4);
	125	long_sleep(10);
	126	}
	127
	128	/* set font height and lines number */
	129	hdc->write_cmd(hdc,
	130	LCD_CMD_FUNCTION_SET \|
	131	((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) \|
	132	((hdc->hd44780_common_flags & LCD_FLAG_F) ?
	133	LCD_CMD_FONT_5X10_DOTS : 0) \|
	134	((hdc->hd44780_common_flags & LCD_FLAG_N) ?
	135	LCD_CMD_TWO_LINES : 0));
	136	long_sleep(10);
	137
	138	/* display off, cursor off, blink off */
	139	hdc->write_cmd(hdc, LCD_CMD_DISPLAY_CTRL);
	140	long_sleep(10);
	141
	142	hdc->write_cmd(hdc,
	143	LCD_CMD_DISPLAY_CTRL \| /* set display mode */
	144	((hdc->hd44780_common_flags & LCD_FLAG_D) ?
	145	LCD_CMD_DISPLAY_ON : 0) \|
	146	((hdc->hd44780_common_flags & LCD_FLAG_C) ?
	147	LCD_CMD_CURSOR_ON : 0) \|
	148	((hdc->hd44780_common_flags & LCD_FLAG_B) ?
	149	LCD_CMD_BLINK_ON : 0));
	150
	151	charlcd_backlight(lcd,
	152	(hdc->hd44780_common_flags & LCD_FLAG_L) ? 1 : 0);
153
154	long_sleep(10);
155
156	/* entry mode set : increment, cursor shifting */
157	hdc->write_cmd(hdc, LCD_CMD_ENTRY_MODE \| LCD_CMD_CURSOR_INC);
158
159	hd44780_common_clear_display(lcd);
160	return 0;
161	}
162	EXPORT_SYMBOL_GPL(hd44780_common_init_display);
163
d2f2187e LP	164	int hd44780_common_shift_cursor(struct charlcd *lcd, enum charlcd_shift_dir dir)
	165	{
	166	struct hd44780_common *hdc = lcd->drvdata;
	167
	168	if (dir == CHARLCD_SHIFT_LEFT) {
	169	/* back one char if not at end of line */
	170	if (lcd->addr.x < hdc->bwidth)
	171	hdc->write_cmd(hdc, LCD_CMD_SHIFT);
	172	} else if (dir == CHARLCD_SHIFT_RIGHT) {
	173	/* allow the cursor to pass the end of the line */
	174	if (lcd->addr.x < (hdc->bwidth - 1))
	175	hdc->write_cmd(hdc,
	176	LCD_CMD_SHIFT \| LCD_CMD_SHIFT_RIGHT);
	177	}
	178
	179	return 0;
	180	}
	181	EXPORT_SYMBOL_GPL(hd44780_common_shift_cursor);
	182
	183	int hd44780_common_shift_display(struct charlcd *lcd,
	184	enum charlcd_shift_dir dir)
	185	{
	186	struct hd44780_common *hdc = lcd->drvdata;
	187
	188	if (dir == CHARLCD_SHIFT_LEFT)
	189	hdc->write_cmd(hdc, LCD_CMD_SHIFT \| LCD_CMD_DISPLAY_SHIFT);
	190	else if (dir == CHARLCD_SHIFT_RIGHT)
	191	hdc->write_cmd(hdc, LCD_CMD_SHIFT \| LCD_CMD_DISPLAY_SHIFT \|
	192	LCD_CMD_SHIFT_RIGHT);
	193
	194	return 0;
	195	}
	196	EXPORT_SYMBOL_GPL(hd44780_common_shift_display);
	197
	198	static void hd44780_common_set_mode(struct hd44780_common *hdc)
	199	{
	200	hdc->write_cmd(hdc,
	201	LCD_CMD_DISPLAY_CTRL \|
	202	((hdc->hd44780_common_flags & LCD_FLAG_D) ?
	203	LCD_CMD_DISPLAY_ON : 0) \|
	204	((hdc->hd44780_common_flags & LCD_FLAG_C) ?
	205	LCD_CMD_CURSOR_ON : 0) \|
	206	((hdc->hd44780_common_flags & LCD_FLAG_B) ?
	207	LCD_CMD_BLINK_ON : 0));
	208	}
	209
	210	int hd44780_common_display(struct charlcd *lcd, enum charlcd_onoff on)
	211	{
	212	struct hd44780_common *hdc = lcd->drvdata;
	213
	214	if (on == CHARLCD_ON)
	215	hdc->hd44780_common_flags \|= LCD_FLAG_D;
	216	else
	217	hdc->hd44780_common_flags &= ~LCD_FLAG_D;
	218
	219	hd44780_common_set_mode(hdc);
	220	return 0;
	221	}
	222	EXPORT_SYMBOL_GPL(hd44780_common_display);
	223
	224	int hd44780_common_cursor(struct charlcd *lcd, enum charlcd_onoff on)
	225	{
	226	struct hd44780_common *hdc = lcd->drvdata;
	227
228	if (on == CHARLCD_ON)
229	hdc->hd44780_common_flags \|= LCD_FLAG_C;
230	else
231	hdc->hd44780_common_flags &= ~LCD_FLAG_C;
232
233	hd44780_common_set_mode(hdc);
234	return 0;
235	}
236	EXPORT_SYMBOL_GPL(hd44780_common_cursor);
237
238	int hd44780_common_blink(struct charlcd *lcd, enum charlcd_onoff on)
239	{
240	struct hd44780_common *hdc = lcd->drvdata;
241
242	if (on == CHARLCD_ON)
243	hdc->hd44780_common_flags \|= LCD_FLAG_B;
244	else
245	hdc->hd44780_common_flags &= ~LCD_FLAG_B;
246
247	hd44780_common_set_mode(hdc);
248	return 0;
249	}
250	EXPORT_SYMBOL_GPL(hd44780_common_blink);
251
252	static void hd44780_common_set_function(struct hd44780_common *hdc)
253	{
254	hdc->write_cmd(hdc,
255	LCD_CMD_FUNCTION_SET \|
256	((hdc->ifwidth == 8) ? LCD_CMD_DATA_LEN_8BITS : 0) \|
257	((hdc->hd44780_common_flags & LCD_FLAG_F) ?
258	LCD_CMD_FONT_5X10_DOTS : 0) \|
259	((hdc->hd44780_common_flags & LCD_FLAG_N) ?
260	LCD_CMD_TWO_LINES : 0));
261	}
262
263	int hd44780_common_fontsize(struct charlcd *lcd, enum charlcd_fontsize size)
264	{
265	struct hd44780_common *hdc = lcd->drvdata;
266
267	if (size == CHARLCD_FONTSIZE_LARGE)
268	hdc->hd44780_common_flags \|= LCD_FLAG_F;
269	else
270	hdc->hd44780_common_flags &= ~LCD_FLAG_F;
271
272	hd44780_common_set_function(hdc);
273	return 0;
274	}
275	EXPORT_SYMBOL_GPL(hd44780_common_fontsize);
276
277	int hd44780_common_lines(struct charlcd *lcd, enum charlcd_lines lines)
278	{
279	struct hd44780_common *hdc = lcd->drvdata;
280
281	if (lines == CHARLCD_LINES_2)
282	hdc->hd44780_common_flags \|= LCD_FLAG_N;
283	else
284	hdc->hd44780_common_flags &= ~LCD_FLAG_N;
285
286	hd44780_common_set_function(hdc);
287	return 0;
288	}
289	EXPORT_SYMBOL_GPL(hd44780_common_lines);
290
339acb08 LP	291	int hd44780_common_redefine_char(struct charlcd lcd, char esc)
	292	{
	293	/* Generator : LGcxxxxx...xx; must have <c> between '0'
	294	* and '7', representing the numerical ASCII code of the
	295	* redefined character, and <xx...xx> a sequence of 16
	296	* hex digits representing 8 bytes for each character.
	297	* Most LCDs will only use 5 lower bits of the 7 first
	298	* bytes.
	299	*/
	300
	301	struct hd44780_common *hdc = lcd->drvdata;
	302	unsigned char cgbytes[8];
	303	unsigned char cgaddr;
	304	int cgoffset;
	305	int shift;
	306	char value;
	307	int addr;
	308
	309	if (!strchr(esc, ';'))
	310	return 0;
	311
	312	esc++;
	313
	314	cgaddr = *(esc++) - '0';
	315	if (cgaddr > 7)
	316	return 1;
	317
	318	cgoffset = 0;
	319	shift = 0;
	320	value = 0;
	321	while (*esc && cgoffset < 8) {
	322	int half;
	323
	324	shift ^= 4;
	325	half = hex_to_bin(*esc++);
	326	if (half < 0)
	327	continue;
	328
	329	value \|= half << shift;
	330	if (shift == 0) {
	331	cgbytes[cgoffset++] = value;
	332	value = 0;
	333	}
	334	}
	335
	336	hdc->write_cmd(hdc, LCD_CMD_SET_CGRAM_ADDR \| (cgaddr * 8));
	337	for (addr = 0; addr < cgoffset; addr++)
	338	hdc->write_data(hdc, cgbytes[addr]);
	339
	340	/* ensures that we stop writing to CGRAM */
40c2b72e	341	lcd->ops->gotoxy(lcd, lcd->addr.x, lcd->addr.y);
339acb08 LP	342	return 1;
	343	}
	344	EXPORT_SYMBOL_GPL(hd44780_common_redefine_char);
	345
718e05ed LP	346	struct hd44780_common *hd44780_common_alloc(void)
	347	{
	348	struct hd44780_common *hd;
	349
	350	hd = kzalloc(sizeof(*hd), GFP_KERNEL);
	351	if (!hd)
	352	return NULL;
	353
3fc04dd7	354	hd->ifwidth = 8;
2545c1c9 LP	355	hd->bwidth = DEFAULT_LCD_BWIDTH;
2545c1c9 LP	356	hd->hwidth = DEFAULT_LCD_HWIDTH;
718e05ed LP	357	return hd;
	358	}
	359	EXPORT_SYMBOL_GPL(hd44780_common_alloc);
	360
	361	MODULE_LICENSE("GPL");