[PATCH] i2c: omap: revert "i2c: omap: switch to threaded IRQ support"
From: paul@pwsan.com (Paul Walmsley)
Date: 2012-10-15 01:51:08
Also in:
linux-i2c, linux-omap
Subsystem:
i2c subsystem, i2c subsystem host drivers, omap i2c driver, omap1 support, omap2+ support, the rest · Maintainers:
Andi Shyti, Vignesh R, Aaro Koskinen, Janusz Krzysztofik, Andreas Kemnade, Kevin Hilman, Roger Quadros, Tony Lindgren, Linus Torvalds
Commit 3b2f8f82dad7d1f79cdc8fc05bd1c94baf109bde ("i2c: omap: switch to
threaded IRQ support") causes communication with I2C devices to fail
after system suspend/resume on all OMAP3 devices:
...
[ 40.228576] PM: noirq resume of devices complete after 3.723 msecs
[ 40.233184] PM: early resume of devices complete after 3.173 msecs
[ 40.242736] [sched_delayed] sched: RT throttling activated
[ 41.235046] omap_i2c omap_i2c.1: controller timed out
[ 41.235351] twl: i2c_read failed to transfer all messages
[ 41.235382] omap_hsmmc omap_hsmmc.0: could not set regulator OCR (-110)
[ 41.396453] mmc0: error -110 during resume (card was removed?)
[ 42.391754] omap_i2c omap_i2c.1: controller timed out
[ 42.391876] twl: i2c_write failed to transfer all messages
[ 42.391906] twl_rtc: Could not write TWLregister F - error -110
[ 43.391326] omap_i2c omap_i2c.1: controller timed out
[ 43.391479] twl: i2c_read failed to transfer all messages
[ 43.391510] twl_rtc: Could not read TWLregister D - error -110
[ 43.391540] twl_rtc twl_rtc: twl_rtc_read_time: reading CTRL_REG, error -110
[ 43.392364] PM: resume of devices complete after 3158.935 msecs
When the root filesystem is on MMC, as in the above example, the
card's voltage regulator is not re-enabled and the filesystem becomes
inaccessible after resume.
Fix by reverting the conversion to a threaded IRQ handler.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Felipe Balbi <redacted>
Cc: Shubhrajyoti D <redacted>
Cc: Wolfram Sang <redacted>
Cc: Ben Dooks <ben-linux@fluff.org>
---
drivers/i2c/busses/i2c-omap.c | 44 +++++++----------------------------------
1 file changed, 7 insertions(+), 37 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index db31eae..e001c2a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c@@ -180,7 +180,6 @@ enum { #define I2C_OMAP_ERRATA_I462 (1 << 1) struct omap_i2c_dev { - spinlock_t lock; /* IRQ synchronization */ struct device *dev; void __iomem *base; /* virtual */ int irq;
@@ -865,35 +864,13 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes, } static irqreturn_t -omap_i2c_isr(int irq, void *dev_id) +omap_i2c_isr(int this_irq, void *dev_id) { struct omap_i2c_dev *dev = dev_id; - irqreturn_t ret = IRQ_HANDLED; - u16 mask; - u16 stat; - - spin_lock(&dev->lock); - mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); - stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); - - if (stat & mask) - ret = IRQ_WAKE_THREAD; - - spin_unlock(&dev->lock); - - return ret; -} - -static irqreturn_t -omap_i2c_isr_thread(int this_irq, void *dev_id) -{ - struct omap_i2c_dev *dev = dev_id; - unsigned long flags; u16 bits; u16 stat; int err = 0, count = 0; - spin_lock_irqsave(&dev->lock, flags); do { bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
@@ -907,7 +884,7 @@ omap_i2c_isr_thread(int this_irq, void *dev_id) if (!stat) { /* my work here is done */ - goto out; + return IRQ_HANDLED; } dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
@@ -1016,8 +993,6 @@ omap_i2c_isr_thread(int this_irq, void *dev_id) omap_i2c_complete_cmd(dev, err); out: - spin_unlock_irqrestore(&dev->lock, flags); - return IRQ_HANDLED; }
@@ -1062,6 +1037,7 @@ omap_i2c_probe(struct platform_device *pdev) pdev->dev.platform_data; struct device_node *node = pdev->dev.of_node; const struct of_device_id *match; + irq_handler_t isr; int irq; int r;
@@ -1110,8 +1086,6 @@ omap_i2c_probe(struct platform_device *pdev) dev->dev = &pdev->dev; dev->irq = irq; - spin_lock_init(&dev->lock); - platform_set_drvdata(pdev, dev); init_completion(&dev->cmd_complete);
@@ -1166,14 +1140,10 @@ omap_i2c_probe(struct platform_device *pdev) /* reset ASAP, clearing any IRQs */ omap_i2c_init(dev); - if (dev->rev < OMAP_I2C_OMAP1_REV_2) - r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr, - IRQF_NO_SUSPEND, pdev->name, dev); - else - r = devm_request_threaded_irq(&pdev->dev, dev->irq, - omap_i2c_isr, omap_i2c_isr_thread, - IRQF_NO_SUSPEND | IRQF_ONESHOT, - pdev->name, dev); + isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr : + omap_i2c_isr; + r = devm_request_irq(&pdev->dev, dev->irq, isr, IRQF_NO_SUSPEND, + pdev->name, dev); if (r) { dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
--
1.7.10.4