This patch fixes two sparse warnings related to lcd_write :
warning: incorrect type in argument 1 (different address spaces)
warning: incorrect type in initializer (incompatible argument 2
(different address spaces))
lcd_write can be used from kernel space (in panel_lcd_print) or from user
space. So we introduce the lcd_write_char function that will write a char to
the device. We modify lcd_write and panel_lcd_print to use it. Finally we add
__user annotation missing in lcd_write.
Signed-off-by: Bastien Armand <armand.bastien@xxxxxxxxxxx>
---
drivers/staging/panel/panel.c | 205 ++++++++++++++++++++++-------------------
1 file changed, 109 insertions(+), 96 deletions(-)
diff --git a/drivers/staging/panel/panel.c b/drivers/staging/panel/panel.c
index 1569e26..dc34254 100644
--- a/drivers/staging/panel/panel.c
+++ b/drivers/staging/panel/panel.c
@@ -1217,111 +1217,113 @@ static inline int handle_lcd_special_code(void)
return processed;
}
+static void lcd_write_char(char c)
+{
+ /* first, we'll test if we're in escape mode */
+ if ((c != '\n') && lcd_escape_len >= 0) {
+ /* yes, let's add this char to the buffer */
+ lcd_escape[lcd_escape_len++] = c;
+ lcd_escape[lcd_escape_len] = 0;
+ } else {
+ /* aborts any previous escape sequence */
+ lcd_escape_len = -1;
+
+ switch (c) {
+ case LCD_ESCAPE_CHAR:
+ /* start of an escape sequence */
+ lcd_escape_len = 0;
+ lcd_escape[lcd_escape_len] = 0;
+ break;
+ case '\b':
+ /* go back one char and clear it */
+ if (lcd_addr_x > 0) {
+ /* check if we're not at the
+ end of the line */
+ if (lcd_addr_x < lcd_bwidth)
+ /* back one char */
+ lcd_write_cmd(0x10);
+ lcd_addr_x--;
+ }
+ /* replace with a space */
+ lcd_write_data(' ');
+ /* back one char again */
+ lcd_write_cmd(0x10);
+ break;
+ case '\014':
+ /* quickly clear the display */
+ lcd_clear_fast();
+ break;
+ 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++)
+ lcd_write_data(' ');
+ 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_gotoxy();
+ break;
+ case '\t':
+ /* print a space instead of the tab */
+ lcd_print(' ');
+ break;
+ default:
+ /* simply print this char */
+ lcd_print(c);
+ break;
+ }
+ }
+
+ /* 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) {
+ int processed = 0;
+
+ if (!strcmp(lcd_escape, "[2J")) {
+ /* clear the display */
+ lcd_clear_fast();
+ processed = 1;
+ } else if (!strcmp(lcd_escape, "[H")) {
+ /* cursor to home */
+ lcd_addr_x = 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')) {
+ 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;
+ } /* escape codes */
+}
+
static ssize_t lcd_write(struct file *file,
- const char *buf, size_t count, loff_t *ppos)
+ const char __user *buf, size_t count, loff_t *ppos)
{
- const char *tmp = buf;
+ const char __user *tmp = buf;
char c;
- for (; count-- > 0; (ppos ? (*ppos)++ : 0), ++tmp) {
+ for (; count-- > 0; (*ppos)++, tmp++) {
if (!in_interrupt() && (((count + 1) & 0x1f) == 0))
/* let's be a little nice with other processes
that need some CPU */
schedule();
- if (ppos == NULL && file == NULL)
- /* let's not use get_user() from the kernel ! */
- c = *tmp;
- else if (get_user(c, tmp))
+ if (get_user(c, buf))
return -EFAULT;
- /* first, we'll test if we're in escape mode */
- if ((c != '\n') && lcd_escape_len >= 0) {
- /* yes, let's add this char to the buffer */
- lcd_escape[lcd_escape_len++] = c;
- lcd_escape[lcd_escape_len] = 0;
- } else {
- /* aborts any previous escape sequence */
- lcd_escape_len = -1;
-
- switch (c) {
- case LCD_ESCAPE_CHAR:
- /* start of an escape sequence */
- lcd_escape_len = 0;
- lcd_escape[lcd_escape_len] = 0;
- break;
- case '\b':
- /* go back one char and clear it */
- if (lcd_addr_x > 0) {
- /* check if we're not at the
- end of the line */
- if (lcd_addr_x < lcd_bwidth)
- /* back one char */
- lcd_write_cmd(0x10);
- lcd_addr_x--;
- }
- /* replace with a space */
- lcd_write_data(' ');
- /* back one char again */
- lcd_write_cmd(0x10);
- break;
- case '\014':
- /* quickly clear the display */
- lcd_clear_fast();
- break;
- 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++)
- lcd_write_data(' ');
- 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_gotoxy();
- break;
- case '\t':
- /* print a space instead of the tab */
- lcd_print(' ');
- break;
- default:
- /* simply print this char */
- lcd_print(c);
- break;
- }
- }
-
- /* 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) {
- int processed = 0;
-
- if (!strcmp(lcd_escape, "[2J")) {
- /* clear the display */
- lcd_clear_fast();
- processed = 1;
- } else if (!strcmp(lcd_escape, "[H")) {
- /* cursor to home */
- lcd_addr_x = 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')) {
- 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;
- } /* escape codes */
+ lcd_write_char(c);
}
return tmp - buf;
@@ -1365,8 +1367,19 @@ static struct miscdevice lcd_dev = {
/* public function usable from the kernel for any purpose */
static void panel_lcd_print(const char *s)
{
- if (lcd_enabled && lcd_initialized)
- lcd_write(NULL, s, strlen(s), NULL);
+ const char *tmp = s;
+ int count = strlen(s);
+
+ 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
+ that need some CPU */
+ schedule();
+
+ lcd_write_char(*tmp);
+ }
+ }
}
/* initialize the LCD driver */
--
1.7.10.4
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
