1 files changed, 63 insertions, 28 deletions

diff --git a/spiflash_n25q128.c b/spiflash_n25q128.c
index 6e35a41..c23f244 100644
--- a/spiflash_n25q128.c
+++ b/spiflash_n25q128.c
@@ -43,6 +43,14 @@
 #define _n25q128_deselect(ctx)	HAL_GPIO_WritePin(ctx->cs_n_port, ctx->cs_n_pin, GPIO_PIN_SET);
 
 
+#define N25Q128_NUM_BYTES	(N25Q128_PAGE_SIZE * N25Q128_NUM_PAGES)
+
+#if N25Q128_SECTOR_SIZE    * N25Q128_NUM_SECTORS    != N25Q128_NUM_BYTES || \
+    N25Q128_SUBSECTOR_SIZE * N25Q128_NUM_SUBSECTORS != N25Q128_NUM_BYTES
+#error Inconsistant definitions for pages / sectors / subsectors
+#endif
+
+
 int _n25q128_get_wel_flag(struct spiflash_ctx *ctx);
 
 
@@ -208,18 +216,30 @@ int n25q128_get_wip_flag(struct spiflash_ctx *ctx)
     return (spi_rx[1] & 1);
 }
 
+/* Wait until the flash memory is done writing (wip = Write In Progress) */
+inline int _wait_while_wip(struct spiflash_ctx *ctx, uint32_t timeout)
+{
+    int i;
+    while (timeout--) {
+	i = n25q128_get_wip_flag(ctx);
+	if (i < 0) return 0;
+	if (! i) break;
+	HAL_Delay(10);
+    }
+    return 1;
+}
 
-int n25q128_erase_sector(struct spiflash_ctx *ctx, uint32_t sector_offset)
+static int n25q128_erase_something(struct spiflash_ctx *ctx, uint8_t command, uint32_t byte_offset)
 {
+    // check offset
+    if (byte_offset >= N25Q128_NUM_BYTES) return 0;
+
     // tx buffer
     uint8_t spi_tx[4];
 
     // result
     HAL_StatusTypeDef ok;
 
-    // check offset
-    if (sector_offset >= N25Q128_NUM_SECTORS) return 0;
-
     // enable writing
     spi_tx[0] = N25Q128_COMMAND_WRITE_ENABLE;
 
@@ -236,14 +256,11 @@ int n25q128_erase_sector(struct spiflash_ctx *ctx, uint32_t sector_offset)
     int wel = _n25q128_get_wel_flag(ctx);
     if (wel != 1) return 0;
 
-    // calculate byte address
-    sector_offset *= N25Q128_SECTOR_SIZE;
-
-    // send ERASE SUBSECTOR command
-    spi_tx[0] = N25Q128_COMMAND_ERASE_SECTOR;
-    spi_tx[1] = (uint8_t)(sector_offset >> 16);
-    spi_tx[2] = (uint8_t)(sector_offset >>  8);
-    spi_tx[3] = (uint8_t)(sector_offset >>  0);
+    // send command (ERASE SECTOR or ERASE SUBSECTOR)
+    spi_tx[0] = command;
+    spi_tx[1] = (uint8_t)(byte_offset >> 16);
+    spi_tx[2] = (uint8_t)(byte_offset >>  8);
+    spi_tx[3] = (uint8_t)(byte_offset >>  0);
 
     // activate, send command, deselect
     _n25q128_select(ctx);
@@ -254,11 +271,29 @@ int n25q128_erase_sector(struct spiflash_ctx *ctx, uint32_t sector_offset)
     // check
     if (ok != HAL_OK) return 0;
 
+    // wait for erase to finish
+
+    if (! _wait_while_wip(ctx, 2000)) return 0;
+
     // done
     return 1;
 }
 
 
+int n25q128_erase_sector(struct spiflash_ctx *ctx, uint32_t sector_offset)
+{
+    return n25q128_erase_something(ctx, N25Q128_COMMAND_ERASE_SECTOR,
+				   sector_offset * N25Q128_SECTOR_SIZE);
+}
+
+
+int n25q128_erase_subsector(struct spiflash_ctx *ctx, uint32_t subsector_offset)
+{
+    return n25q128_erase_something(ctx, N25Q128_COMMAND_ERASE_SUBSECTOR,
+				   subsector_offset * N25Q128_SUBSECTOR_SIZE);
+}
+
+
 int _n25q128_get_wel_flag(struct spiflash_ctx *ctx)
 {
     // tx, rx buffers
@@ -284,21 +319,8 @@ int _n25q128_get_wel_flag(struct spiflash_ctx *ctx)
     return ((spi_rx[1] >> 1) & 1);
 }
 
-/* Wait until the flash memory is done writing (wip = Write In Progress) */
-inline int _wait_while_wip(struct spiflash_ctx *ctx, uint32_t timeout)
-{
-    int i;
-    while (timeout--) {
-	i = n25q128_get_wip_flag(ctx);
-	if (i < 0) return 0;
-	if (! i) break;
-	HAL_Delay(10);
-    }
-    return 1;
-}
-
 /* This function performs erasure if needed, and then writing of a number of pages to the flash memory */
-int n25q128_write_data(struct spiflash_ctx *ctx, uint32_t offset, const uint8_t *buf, const uint32_t len)
+int n25q128_write_data(struct spiflash_ctx *ctx, uint32_t offset, const uint8_t *buf, const uint32_t len, const int auto_erase)
 {
     uint32_t page;
 
@@ -306,8 +328,15 @@ int n25q128_write_data(struct spiflash_ctx *ctx, uint32_t offset, const uint8_t
     if ((offset % N25Q128_PAGE_SIZE) != 0) return -1;
     if ((len % N25Q128_PAGE_SIZE) != 0) return -2;
 
-    if ((offset % N25Q128_SECTOR_SIZE) == 0) {
-	/* first page in sector, need to erase sector */
+    if (auto_erase && (offset % N25Q128_SECTOR_SIZE) == 0) {
+	/*
+	 * first page in sector, need to erase sector
+	 *
+	 * So why do we only do this when the buffer starts on the
+	 * sector, as opposed to performing this check for every page?
+	 * Also, might be better to do this by subsectors rather than
+	 * sectors.
+	 */
 
 	if (! _wait_while_wip(ctx, 1000)) return -3;
 
@@ -330,6 +359,12 @@ int n25q128_write_data(struct spiflash_ctx *ctx, uint32_t offset, const uint8_t
 	 */
     }
 
+    /*
+     * Wait until last write finishes.
+     */
+
+    if (! _wait_while_wip(ctx, 1000)) return -7;
+
     return 1;
 }