From 2c22120fbd017d78ad2b6825ba573db3ef539bca Mon Sep 17 00:00:00 2001 From: Kyungmin Park Date: Thu, 16 Nov 2006 11:23:48 +0900 Subject: [PATCH] MTD: OneNAND: interrupt based wait support We can use the two methods to wait. 1. polling: read interrupt status register 2. interrupt: use kernel ineterrupt mechanism To use interrupt method, you first connect onenand interrupt pin to your platform and configure interrupt properly Signed-off-by: Kyungmin Park --- drivers/mtd/onenand/generic.c | 1 + drivers/mtd/onenand/onenand_base.c | 109 ++++++++++++++++++++++++++++- include/linux/mtd/onenand.h | 4 ++ 3 files changed, 112 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/onenand/generic.c b/drivers/mtd/onenand/generic.c index af06a80f44de..cdf80c68160f 100644 --- a/drivers/mtd/onenand/generic.c +++ b/drivers/mtd/onenand/generic.c @@ -63,6 +63,7 @@ static int __devinit generic_onenand_probe(struct device *dev) } info->onenand.mmcontrol = pdata->mmcontrol; + info->onenand.irq = platform_get_irq(pdev, 0); info->mtd.name = pdev->dev.bus_id; info->mtd.priv = &info->onenand; diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c index 8ed68b28afe3..aea13a388868 100644 --- a/drivers/mtd/onenand/onenand_base.c +++ b/drivers/mtd/onenand/onenand_base.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -339,6 +340,111 @@ static int onenand_wait(struct mtd_info *mtd, int state) return 0; } +/* + * onenand_interrupt - [DEFAULT] onenand interrupt handler + * @param irq onenand interrupt number + * @param dev_id interrupt data + * + * complete the work + */ +static irqreturn_t onenand_interrupt(int irq, void *data) +{ + struct onenand_chip *this = (struct onenand_chip *) data; + + /* To handle shared interrupt */ + if (!this->complete.done) + complete(&this->complete); + + return IRQ_HANDLED; +} + +/* + * onenand_interrupt_wait - [DEFAULT] wait until the command is done + * @param mtd MTD device structure + * @param state state to select the max. timeout value + * + * Wait for command done. + */ +static int onenand_interrupt_wait(struct mtd_info *mtd, int state) +{ + struct onenand_chip *this = mtd->priv; + + /* To prevent soft lockup */ + touch_softlockup_watchdog(); + + wait_for_completion(&this->complete); + + return onenand_wait(mtd, state); +} + +/* + * onenand_try_interrupt_wait - [DEFAULT] try interrupt wait + * @param mtd MTD device structure + * @param state state to select the max. timeout value + * + * Try interrupt based wait (It is used one-time) + */ +static int onenand_try_interrupt_wait(struct mtd_info *mtd, int state) +{ + struct onenand_chip *this = mtd->priv; + unsigned long remain, timeout; + + /* We use interrupt wait first */ + this->wait = onenand_interrupt_wait; + + /* To prevent soft lockup */ + touch_softlockup_watchdog(); + + timeout = msecs_to_jiffies(100); + remain = wait_for_completion_timeout(&this->complete, timeout); + if (!remain) { + printk(KERN_INFO "OneNAND: There's no interrupt. " + "We use the normal wait\n"); + + /* Release the irq */ + free_irq(this->irq, this); + + this->wait = onenand_wait; + } + + return onenand_wait(mtd, state); +} + +/* + * onenand_setup_wait - [OneNAND Interface] setup onenand wait method + * @param mtd MTD device structure + * + * There's two method to wait onenand work + * 1. polling - read interrupt status register + * 2. interrupt - use the kernel interrupt method + */ +static void onenand_setup_wait(struct mtd_info *mtd) +{ + struct onenand_chip *this = mtd->priv; + int syscfg; + + init_completion(&this->complete); + + if (this->irq <= 0) { + this->wait = onenand_wait; + return; + } + + if (request_irq(this->irq, &onenand_interrupt, + IRQF_SHARED, "onenand", this)) { + /* If we can't get irq, use the normal wait */ + this->wait = onenand_wait; + return; + } + + /* Enable interrupt */ + syscfg = this->read_word(this->base + ONENAND_REG_SYS_CFG1); + syscfg |= ONENAND_SYS_CFG1_IOBE; + this->write_word(syscfg, this->base + ONENAND_REG_SYS_CFG1); + + this->wait = onenand_try_interrupt_wait; +} + /** * onenand_bufferram_offset - [DEFAULT] BufferRAM offset * @param mtd MTD data structure @@ -1129,7 +1235,6 @@ static void onenand_sync(struct mtd_info *mtd) onenand_release_device(mtd); } - /** * onenand_block_isbad - [MTD Interface] Check whether the block at the given offset is bad * @param mtd MTD device structure @@ -1846,7 +1951,7 @@ int onenand_scan(struct mtd_info *mtd, int maxchips) if (!this->command) this->command = onenand_command; if (!this->wait) - this->wait = onenand_wait; + onenand_setup_wait(mtd); if (!this->read_bufferram) this->read_bufferram = onenand_read_bufferram; diff --git a/include/linux/mtd/onenand.h b/include/linux/mtd/onenand.h index 6f045b586e76..df963f1f6f87 100644 --- a/include/linux/mtd/onenand.h +++ b/include/linux/mtd/onenand.h @@ -13,6 +13,7 @@ #define __LINUX_MTD_ONENAND_H #include +#include #include #include @@ -120,6 +121,9 @@ struct onenand_chip { int (*block_markbad)(struct mtd_info *mtd, loff_t ofs); int (*scan_bbt)(struct mtd_info *mtd); + struct completion complete; + int irq; + spinlock_t chip_lock; wait_queue_head_t wq; onenand_state_t state;