From e4b2a96aeb2b3dfee8d19d0335c6151d4cca4631 Mon Sep 17 00:00:00 2001 From: Robert Jarzmik Date: Sat, 19 Nov 2011 16:02:56 +0100 Subject: mtd: docg3: add suspend and resume Add functions to powerdown and powerup from suspend, in order to save power. Signed-off-by: Robert Jarzmik Reviewed-by: Ivan Djelic Reviewed-by: Mike Dunn Signed-off-by: David Woodhouse --- drivers/mtd/devices/docg3.c | 75 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 74 insertions(+), 1 deletion(-) (limited to 'drivers/mtd/devices/docg3.c') diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c index 26cc17909b16..d94c759d3ea7 100644 --- a/drivers/mtd/devices/docg3.c +++ b/drivers/mtd/devices/docg3.c @@ -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), }; -- cgit v1.2.3