[PATCH] mtd: m25p80: Add Power Management support
Hou Zhiqiang
b48286 at freescale.com
Wed Dec 11 03:19:30 EST 2013
Add PM support using callback function suspend and resume in .driver of
spi_driver.
Signed-off-by: Hou Zhiqiang <b48286 at freescale.com>
---
drivers/mtd/devices/m25p80.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index 7eda71d..b0c2b8c 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -66,6 +66,8 @@
/* Used for Spansion flashes only. */
#define OPCODE_BRWR 0x17 /* Bank register write */
+#define OPCODE_DP 0xb9 /* Enter deep power down mode */
+#define OPCODE_RES 0xab /* Exit deep power down mode */
/* Status Register bits. */
#define SR_WIP 1 /* Write in progress */
@@ -1128,11 +1130,46 @@ static int m25p_remove(struct spi_device *spi)
return mtd_device_unregister(&flash->mtd);
}
+#ifdef CONFIG_PM
+static int m25p_suspend(struct device *dev, pm_message_t mesg)
+{
+ struct m25p *flash = dev_get_drvdata(dev);
+ int ret;
+
+ flash->command[0] = OPCODE_DP;
+ mutex_lock(&flash->lock);
+ /* Wait until finished previous write/erase command. */
+ ret = wait_till_ready(flash);
+ if (ret) {
+ mutex_unlock(&flash->lock);
+ return ret;
+ }
+ ret = spi_write(flash->spi, flash->command, 1);
+ mutex_unlock(&flash->lock);
+
+ return ret;
+}
+
+static int m25p_resume(struct device *dev)
+{
+ struct m25p *flash = dev_get_drvdata(dev);
+ int ret;
+
+ flash->command[0] = OPCODE_RES;
+ ret = spi_write(flash->spi, flash->command, 1);
+
+ return ret;
+}
+#endif /* CONFIG_PM */
static struct spi_driver m25p80_driver = {
.driver = {
.name = "m25p80",
.owner = THIS_MODULE,
+#ifdef CONFIG_PM
+ .suspend = m25p_suspend,
+ .resume = m25p_resume,
+#endif
},
.id_table = m25p_ids,
.probe = m25p_probe,
--
1.8.4.1
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