5.0-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 93b6604c5a669d84e45fe5129294875bf82eb1ff ]
A previous change allowed I2C client devices to discover new IRQs upon reprobe by clearing the IRQ in i2c_device_remove. However, if an IRQ was assigned in i2c_new_device, that information is lost.
For example, the touchscreen and trackpad devices on a Dell Inspiron laptop are I2C devices whose IRQs are defined by ACPI extended IRQ types. The client device structures are initialized during an ACPI walk. After removing the i2c_hid device, modprobe fails.
This change caches the initial IRQ value in i2c_new_device and then resets the client device IRQ to the initial value in i2c_device_remove.
Fixes: 6f108dd70d30 ("i2c: Clear client->irq in i2c_device_remove") Signed-off-by: Jim Broadus jbroadus@gmail.com Reviewed-by: Benjamin Tissoires benjamin.tissoires@redhat.com Reviewed-by: Charles Keepax ckeepax@opensource.cirrus.com [wsa: this is an easy to backport fix for the regression. We will refactor the code to handle irq assignments better in general.] Signed-off-by: Wolfram Sang wsa@the-dreams.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/i2c/i2c-core-base.c | 9 +++++---- include/linux/i2c.h | 1 + 2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 28460f6a60cc..af87a16ac3a5 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -430,7 +430,7 @@ static int i2c_device_remove(struct device *dev) dev_pm_clear_wake_irq(&client->dev); device_init_wakeup(&client->dev, false);
- client->irq = 0; + client->irq = client->init_irq;
return status; } @@ -741,10 +741,11 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) client->flags = info->flags; client->addr = info->addr;
- client->irq = info->irq; - if (!client->irq) - client->irq = i2c_dev_irq_from_resources(info->resources, + client->init_irq = info->irq; + if (!client->init_irq) + client->init_irq = i2c_dev_irq_from_resources(info->resources, info->num_resources); + client->irq = client->init_irq;
strlcpy(client->name, info->type, sizeof(client->name));
diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 65b4eaed1d96..7e748648c7d3 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -333,6 +333,7 @@ struct i2c_client { char name[I2C_NAME_SIZE]; struct i2c_adapter *adapter; /* the adapter we sit on */ struct device dev; /* the device structure */ + int init_irq; /* irq set at initialization */ int irq; /* irq issued by device */ struct list_head detected; #if IS_ENABLED(CONFIG_I2C_SLAVE)