From 285df995f90e3d61d97f327d34b9659d92313314 Mon Sep 17 00:00:00 2001 From: Andreas Kemnade Date: Fri, 28 Feb 2025 15:04:20 +0100 Subject: [PATCH 1/4] i2c: omap: fix IRQ storms On the GTA04A5 writing a reset command to the gyroscope causes IRQ storms because NACK IRQs are enabled and therefore triggered but not acked. Sending a reset command to the gyroscope by i2cset 1 0x69 0x14 0xb6 with an additional debug print in the ISR (not the thread) itself causes [ 363.353515] i2c i2c-1: ioctl, cmd=0x720, arg=0xbe801b00 [ 363.359039] omap_i2c 48072000.i2c: addr: 0x0069, len: 2, flags: 0x0, stop: 1 [ 363.366180] omap_i2c 48072000.i2c: IRQ LL (ISR = 0x1110) [ 363.371673] omap_i2c 48072000.i2c: IRQ (ISR = 0x0010) [ 363.376892] omap_i2c 48072000.i2c: IRQ LL (ISR = 0x0102) [ 363.382263] omap_i2c 48072000.i2c: IRQ LL (ISR = 0x0102) [ 363.387664] omap_i2c 48072000.i2c: IRQ LL (ISR = 0x0102) repeating till infinity [...] (0x2 = NACK, 0x100 = Bus free, which is not enabled) Apparently no other IRQ bit gets set, so this stalls. Do not ignore enabled interrupts and make sure they are acked. If the NACK IRQ is not needed, it should simply not enabled, but according to the above log, caring about it is necessary unless the Bus free IRQ is enabled and handled. The assumption that is will always come with a ARDY IRQ, which was the idea behind ignoring it, proves wrong. It is true for simple reads from an unused address. To still avoid the i2cdetect trouble which is the reason for commit c770657bd261 ("i2c: omap: Fix standard mode false ACK readings"), avoid doing much about NACK in omap_i2c_xfer_data() which is used by both IRQ mode and polling mode, so also the false detection fix is extended to polling usage and IRQ storms are avoided. By changing this, the hardirq handler is not needed anymore to filter stuff. The mentioned gyro reset now just causes a -ETIMEDOUT instead of hanging the system. Fixes: c770657bd261 ("i2c: omap: Fix standard mode false ACK readings"). CC: stable@kernel.org Signed-off-by: Andreas Kemnade Tested-by: Nishanth Menon Reviewed-by: Aniket Limaye Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/20250228140420.379498-1-andreas@kemnade.info --- drivers/i2c/busses/i2c-omap.c | 26 +++++++------------------- 1 file changed, 7 insertions(+), 19 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 92faf03d64cfb..f18c3e74b0762 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -1048,23 +1048,6 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *omap, u8 num_bytes, return 0; } -static irqreturn_t -omap_i2c_isr(int irq, void *dev_id) -{ - struct omap_i2c_dev *omap = dev_id; - irqreturn_t ret = IRQ_HANDLED; - u16 mask; - u16 stat; - - stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); - mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG) & ~OMAP_I2C_STAT_NACK; - - if (stat & mask) - ret = IRQ_WAKE_THREAD; - - return ret; -} - static int omap_i2c_xfer_data(struct omap_i2c_dev *omap) { u16 bits; @@ -1095,8 +1078,13 @@ static int omap_i2c_xfer_data(struct omap_i2c_dev *omap) } if (stat & OMAP_I2C_STAT_NACK) { - err |= OMAP_I2C_STAT_NACK; + omap->cmd_err |= OMAP_I2C_STAT_NACK; omap_i2c_ack_stat(omap, OMAP_I2C_STAT_NACK); + + if (!(stat & ~OMAP_I2C_STAT_NACK)) { + err = -EAGAIN; + break; + } } if (stat & OMAP_I2C_STAT_AL) { @@ -1472,7 +1460,7 @@ omap_i2c_probe(struct platform_device *pdev) IRQF_NO_SUSPEND, pdev->name, omap); else r = devm_request_threaded_irq(&pdev->dev, omap->irq, - omap_i2c_isr, omap_i2c_isr_thread, + NULL, omap_i2c_isr_thread, IRQF_NO_SUSPEND | IRQF_ONESHOT, pdev->name, omap); From 9b5463f349d019a261f1e80803447efca3126151 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Mon, 3 Mar 2025 20:53:08 +0100 Subject: [PATCH 2/4] i2c: ali1535: Fix an error handling path in ali1535_probe() If i2c_add_adapter() fails, the request_region() call in ali1535_setup() must be undone by a corresponding release_region() call, as done in the remove function. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Christophe JAILLET Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/0daf63d7a2ce74c02e2664ba805bbfadab7d25e5.1741031571.git.christophe.jaillet@wanadoo.fr --- drivers/i2c/busses/i2c-ali1535.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-ali1535.c b/drivers/i2c/busses/i2c-ali1535.c index 544c94e86b896..1eac358380405 100644 --- a/drivers/i2c/busses/i2c-ali1535.c +++ b/drivers/i2c/busses/i2c-ali1535.c @@ -485,6 +485,8 @@ MODULE_DEVICE_TABLE(pci, ali1535_ids); static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id) { + int ret; + if (ali1535_setup(dev)) { dev_warn(&dev->dev, "ALI1535 not detected, module not inserted.\n"); @@ -496,7 +498,15 @@ static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id) snprintf(ali1535_adapter.name, sizeof(ali1535_adapter.name), "SMBus ALI1535 adapter at %04x", ali1535_offset); - return i2c_add_adapter(&ali1535_adapter); + ret = i2c_add_adapter(&ali1535_adapter); + if (ret) + goto release_region; + + return 0; + +release_region: + release_region(ali1535_smba, ALI1535_SMB_IOSIZE); + return ret; } static void ali1535_remove(struct pci_dev *dev) From 6e55caaf30c88209d097e575a169b1dface1ab69 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Mon, 3 Mar 2025 20:58:06 +0100 Subject: [PATCH 3/4] i2c: ali15x3: Fix an error handling path in ali15x3_probe() If i2c_add_adapter() fails, the request_region() call in ali15x3_setup() must be undone by a corresponding release_region() call, as done in the remove function. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Christophe JAILLET Signed-off-by: Andi Shyti Link: https://lore.kernel.org/r/9b2090cbcc02659f425188ea05f2e02745c4e67b.1741031878.git.christophe.jaillet@wanadoo.fr --- drivers/i2c/busses/i2c-ali15x3.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-ali15x3.c b/drivers/i2c/busses/i2c-ali15x3.c index 4761c72081022..418d11266671e 100644 --- a/drivers/i2c/busses/i2c-ali15x3.c +++ b/drivers/i2c/busses/i2c-ali15x3.c @@ -472,6 +472,8 @@ MODULE_DEVICE_TABLE (pci, ali15x3_ids); static int ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id) { + int ret; + if (ali15x3_setup(dev)) { dev_err(&dev->dev, "ALI15X3 not detected, module not inserted.\n"); @@ -483,7 +485,15 @@ static int ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id) snprintf(ali15x3_adapter.name, sizeof(ali15x3_adapter.name), "SMBus ALI15X3 adapter at %04x", ali15x3_smba); - return i2c_add_adapter(&ali15x3_adapter); + ret = i2c_add_adapter(&ali15x3_adapter); + if (ret) + goto release_region; + + return 0; + +release_region: + release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE); + return ret; } static void ali15x3_remove(struct pci_dev *dev) From 2b22459792fcb4def9f0936d64575ac11a95a58d Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Mon, 3 Mar 2025 21:26:54 +0100 Subject: [PATCH 4/4] i2c: sis630: Fix an error handling path in sis630_probe() If i2c_add_adapter() fails, the request_region() call in sis630_setup() must be undone by a corresponding release_region() call, as done in the remove function. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Christophe JAILLET Link: https://lore.kernel.org/r/3d607601f2c38e896b10207963c6ab499ca5c307.1741033587.git.christophe.jaillet@wanadoo.fr Signed-off-by: Andi Shyti --- drivers/i2c/busses/i2c-sis630.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-sis630.c b/drivers/i2c/busses/i2c-sis630.c index 3505cf29cedda..a19c3d251804d 100644 --- a/drivers/i2c/busses/i2c-sis630.c +++ b/drivers/i2c/busses/i2c-sis630.c @@ -509,6 +509,8 @@ MODULE_DEVICE_TABLE(pci, sis630_ids); static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id) { + int ret; + if (sis630_setup(dev)) { dev_err(&dev->dev, "SIS630 compatible bus not detected, " @@ -522,7 +524,15 @@ static int sis630_probe(struct pci_dev *dev, const struct pci_device_id *id) snprintf(sis630_adapter.name, sizeof(sis630_adapter.name), "SMBus SIS630 adapter at %04x", smbus_base + SMB_STS); - return i2c_add_adapter(&sis630_adapter); + ret = i2c_add_adapter(&sis630_adapter); + if (ret) + goto release_region; + + return 0; + +release_region: + release_region(smbus_base + SMB_STS, SIS630_SMB_IOREGION); + return ret; } static void sis630_remove(struct pci_dev *dev)