481-mtd-add-spi-flash-reset-code.patch

Index: linux-4.4.40/drivers/mtd/devices/m25p80.c
===================================================================
--- linux-4.4.40.orig/drivers/mtd/devices/m25p80.c
+++ linux-4.4.40/drivers/mtd/devices/m25p80.c
@@ -261,6 +261,12 @@ static int m25p_remove(struct spi_device
 {
 	struct m25p	*flash = spi_get_drvdata(spi);
 
+	// addition for reboot: spi flash reset code
+        flash->command[0] = 0x66;
+        spi_write(flash->spi,flash->command,1);
+        flash->command[0] = 0x99;
+        spi_write(flash->spi,flash->command,1);
+
 	/* Clean up MTD stuff. */
 	return mtd_device_unregister(&flash->spi_nor.mtd);
 }
@@ -328,6 +334,7 @@ static struct spi_driver m25p80_driver =
 	.id_table	= m25p_ids,
 	.probe	= m25p_probe,
 	.remove	= m25p_remove,
+	.shutdown = m25p_remove, // addition for spi flash reset code
 
 	/* REVISIT: many of these chips have deep power-down modes, which
 	 * should clearly be entered on suspend() to minimize power use.