[PATCH v2 3/3] staging: exfat: add millisecond support

[Valentin Vidic]

Use create_time_ms modify_time_ms fields to store the millisecond
part of the file timestamp with the precision of 10 ms.

Signed-off-by: Valentin Vidic <vvidic@xxxxxxxxxxxxxxxxxxxxxx>
---
 drivers/staging/exfat/exfat_core.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/staging/exfat/exfat_core.c b/drivers/staging/exfat/exfat_core.c
index 8476eeedba83..e87119fa8c0a 100644
--- a/drivers/staging/exfat/exfat_core.c
+++ b/drivers/staging/exfat/exfat_core.c
@@ -1139,6 +1139,7 @@ void exfat_set_entry_size(struct dentry_t *p_entry, u64 size)
 void fat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 			u8 mode)
 {
+	u8 ms = 0;
 	u16 t = 0x00, d = 0x21;
 	struct dos_dentry_t *ep = (struct dos_dentry_t *)p_entry;
 
@@ -1146,6 +1147,7 @@ void fat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 	case TM_CREATE:
 		t = GET16_A(ep->create_time);
 		d = GET16_A(ep->create_date);
+		ms = ep->create_time_ms * 10;
 		break;
 	case TM_MODIFY:
 		t = GET16_A(ep->modify_time);
@@ -1159,11 +1161,17 @@ void fat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 	tp->day  = (d & 0x001F);
 	tp->mon  = (d >> 5) & 0x000F;
 	tp->year = (d >> 9);
+
+	if (ms >= 1000) {
+		ms -= 1000;
+		tp->sec++;
+	}
 }
 
 void exfat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 			  u8 mode)
 {
+	u8 ms = 0;
 	u16 t = 0x00, d = 0x21;
 	struct file_dentry_t *ep = (struct file_dentry_t *)p_entry;
 
@@ -1171,10 +1179,12 @@ void exfat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 	case TM_CREATE:
 		t = GET16_A(ep->create_time);
 		d = GET16_A(ep->create_date);
+		ms = ep->create_time_ms * 10;
 		break;
 	case TM_MODIFY:
 		t = GET16_A(ep->modify_time);
 		d = GET16_A(ep->modify_date);
+		ms = ep->modify_time_ms * 10;
 		break;
 	case TM_ACCESS:
 		t = GET16_A(ep->access_time);
@@ -1188,21 +1198,33 @@ void exfat_get_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 	tp->day  = (d & 0x001F);
 	tp->mon  = (d >> 5) & 0x000F;
 	tp->year = (d >> 9);
+
+	if (ms >= 1000) {
+		ms -= 1000;
+		tp->sec++;
+	}
 }
 
 void fat_set_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 			u8 mode)
 {
+	u8 ms;
 	u16 t, d;
 	struct dos_dentry_t *ep = (struct dos_dentry_t *)p_entry;
 
 	t = (tp->hour << 11) | (tp->min << 5) | (tp->sec >> 1);
 	d = (tp->year <<  9) | (tp->mon << 5) |  tp->day;
 
+	ms = tp->millisec;
+	if (tp->sec & 1) {
+		ms += 1000;
+	}
+
 	switch (mode) {
 	case TM_CREATE:
 		SET16_A(ep->create_time, t);
 		SET16_A(ep->create_date, d);
+		ep->create_time_ms = ms / 10;
 		break;
 	case TM_MODIFY:
 		SET16_A(ep->modify_time, t);
@@ -1214,20 +1236,28 @@ void fat_set_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 void exfat_set_entry_time(struct dentry_t *p_entry, struct timestamp_t *tp,
 			  u8 mode)
 {
+	u8 ms;
 	u16 t, d;
 	struct file_dentry_t *ep = (struct file_dentry_t *)p_entry;
 
 	t = (tp->hour << 11) | (tp->min << 5) | (tp->sec >> 1);
 	d = (tp->year <<  9) | (tp->mon << 5) |  tp->day;
 
+	ms = tp->millisec;
+	if (tp->sec & 1) {
+		ms += 1000;
+	}
+
 	switch (mode) {
 	case TM_CREATE:
 		SET16_A(ep->create_time, t);
 		SET16_A(ep->create_date, d);
+		ep->create_time_ms = ms / 10;
 		break;
 	case TM_MODIFY:
 		SET16_A(ep->modify_time, t);
 		SET16_A(ep->modify_date, d);
+		ep->modify_time_ms = ms / 10;
 		break;
 	case TM_ACCESS:
 		SET16_A(ep->access_time, t);
-- 
2.20.1