mtd: docg3: add suspend and resume

Add functions to powerdown and powerup from suspend, in
order to save power.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Reviewed-by: Ivan Djelic <ivan.djelic@parrot.com>
Reviewed-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Robert Jarzmik 2011-11-19 16:02:56 +01:00 committed by David Woodhouse
parent d13d19ece3
commit e4b2a96aeb
2 changed files with 80 additions and 1 deletions

View file

@ -45,7 +45,6 @@
* As no specification is available from M-Systems/Sandisk, this drivers lacks
* several functions available on the chip, as :
* - IPL write
* - powerdown / powerup
*
* The bus data width (8bits versus 16bits) is not handled (if_cfg flag), and
* the driver assumes a 16bits data bus.
@ -1755,6 +1754,78 @@ static void doc_release_device(struct mtd_info *mtd)
kfree(mtd);
}
/**
* docg3_resume - Awakens docg3 floor
* @pdev: platfrom device
*
* Returns 0 (always successfull)
*/
static int docg3_resume(struct platform_device *pdev)
{
int i;
struct mtd_info **docg3_floors, *mtd;
struct docg3 *docg3;
docg3_floors = platform_get_drvdata(pdev);
mtd = docg3_floors[0];
docg3 = mtd->priv;
doc_dbg("docg3_resume()\n");
for (i = 0; i < 12; i++)
doc_readb(docg3, DOC_IOSPACE_IPL);
return 0;
}
/**
* docg3_suspend - Put in low power mode the docg3 floor
* @pdev: platform device
* @state: power state
*
* Shuts off most of docg3 circuitery to lower power consumption.
*
* Returns 0 if suspend succeeded, -EIO if chip refused suspend
*/
static int docg3_suspend(struct platform_device *pdev, pm_message_t state)
{
int floor, i;
struct mtd_info **docg3_floors, *mtd;
struct docg3 *docg3;
u8 ctrl, pwr_down;
docg3_floors = platform_get_drvdata(pdev);
for (floor = 0; floor < DOC_MAX_NBFLOORS; floor++) {
mtd = docg3_floors[floor];
if (!mtd)
continue;
docg3 = mtd->priv;
doc_writeb(docg3, floor, DOC_DEVICESELECT);
ctrl = doc_register_readb(docg3, DOC_FLASHCONTROL);
ctrl &= ~DOC_CTRL_VIOLATION & ~DOC_CTRL_CE;
doc_writeb(docg3, ctrl, DOC_FLASHCONTROL);
for (i = 0; i < 10; i++) {
usleep_range(3000, 4000);
pwr_down = doc_register_readb(docg3, DOC_POWERMODE);
if (pwr_down & DOC_POWERDOWN_READY)
break;
}
if (pwr_down & DOC_POWERDOWN_READY) {
doc_dbg("docg3_suspend(): floor %d powerdown ok\n",
floor);
} else {
doc_err("docg3_suspend(): floor %d powerdown failed\n",
floor);
return -EIO;
}
}
mtd = docg3_floors[0];
docg3 = mtd->priv;
doc_set_asic_mode(docg3, DOC_ASICMODE_POWERDOWN);
return 0;
}
/**
* doc_probe - Probe the IO space for a DiskOnChip G3 chip
* @pdev: platform device
@ -1860,6 +1931,8 @@ static struct platform_driver g3_driver = {
.name = "docg3",
.owner = THIS_MODULE,
},
.suspend = docg3_suspend,
.resume = docg3_resume,
.remove = __exit_p(docg3_release),
};

View file

@ -127,6 +127,7 @@
#define DOC_ASICMODECONFIRM 0x1072
#define DOC_CHIPID_INV 0x1074
#define DOC_POWERMODE 0x107c
/*
* Flash sequences
@ -238,6 +239,11 @@
#define DOC_READADDR_ONE_BYTE 0x4000
#define DOC_READADDR_ADDR_MASK 0x1fff
/*
* Flash register : DOC_POWERMODE
*/
#define DOC_POWERDOWN_READY 0x80
/*
* Status of erase and write operation
*/