From: Ranjit Waghmode <ranjit.waghmode@xilinx.com>
Date: Tue, 24 Nov 2015 05:46:28 +0000 (+0530)
Subject: mtd: spi-nor: reset QSPI page on to 0 on reboot/shutdown
X-Git-Tag: xilinx-v2015.4.01~39
X-Git-Url: https://rtime.felk.cvut.cz/gitweb/zynq/linux.git/commitdiff_plain/aab0b63545a1db7ece331cb4974ef7ef9dfe7252

mtd: spi-nor: reset QSPI page on to 0 on reboot/shutdown

This patch adds functionality to reset the QSPI page on 0
on reboot or shutdown.

Signed-off-by: Ranjit Waghmode <ranjit.waghmode@xilinx.com>
Reviewed-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
---

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 7b7dea261106..ebc8d78f25cd 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -248,6 +248,13 @@ static int m25p_remove(struct spi_device *spi)
 	return mtd_device_unregister(&flash->mtd);
 }
 
+static void m25p_shutdown(struct spi_device *spi)
+{
+	struct m25p *flash = spi_get_drvdata(spi);
+
+	spi_nor_shutdown(&flash->spi_nor);
+}
+
 /*
  * XXX This needs to be kept in sync with spi_nor_ids.  We can't share
  * it with spi-nor, because if this is built as a module then modpost
@@ -307,6 +314,7 @@ static struct spi_driver m25p80_driver = {
 	.id_table	= m25p_ids,
 	.probe	= m25p_probe,
 	.remove	= m25p_remove,
+	.shutdown = m25p_shutdown,
 
 	/* REVISIT: many of these chips have deep power-down modes, which
 	 * should clearly be entered on suspend() to minimize power use.
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index dd895452c403..1211fdd14d21 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1796,6 +1796,14 @@ static const struct spi_device_id *spi_nor_match_id(const char *name)
 	return NULL;
 }
 
+void spi_nor_shutdown(struct spi_nor *nor)
+{
+	if (nor->addr_width == 3 &&
+		(nor->mtd->size >> nor->shift) > 0x1000000)
+		write_ear(nor, 0);
+}
+EXPORT_SYMBOL_GPL(spi_nor_shutdown);
+
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Huang Shijie <shijie8@gmail.com>");
 MODULE_AUTHOR("Mike Lavender");
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index d752c5cb4215..a1001177cbff 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -236,4 +236,13 @@ struct spi_nor {
  */
 int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode);
 
+/**
+ * spi_nor_shutdown() - prepare for reboot
+ * @nor:	the spi_nor structure
+ *
+ * The drivers can use this fuction to get the address back to
+ * 0 as will be required for a ROM boot.
+ */
+void spi_nor_shutdown(struct spi_nor *nor);
+
 #endif