mirror of
https://github.com/torvalds/linux.git
synced 2024-09-20 06:53:04 +00:00
a3368e1186
Since commitaa49c90894("i2c: core: Run atomic i2c xfer when !preemptible"), the whole reboot/power off sequence on non-preempt kernels is using atomic i2c xfer, as !preemptible() always results to 1. During device_shutdown(), the i2c might be used a lot and not all busses have implemented an atomic xfer handler. This results in a lot of avoidable noise, like: [ 12.687169] No atomic I2C transfer handler for 'i2c-0' [ 12.692313] WARNING: CPU: 6 PID: 275 at drivers/i2c/i2c-core.h:40 i2c_smbus_xfer+0x100/0x118 ... Fix this by allowing non-atomic xfer when the interrupts are enabled, as it was before. Link: https://lore.kernel.org/r/20231222230106.73f030a5@yea Link: https://lore.kernel.org/r/20240102150350.3180741-1-mwalle@kernel.org Link: https://lore.kernel.org/linux-i2c/13271b9b-4132-46ef-abf8-2c311967bb46@mailbox.org/ Fixes:aa49c90894("i2c: core: Run atomic i2c xfer when !preemptible") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Benjamin Bara <benjamin.bara@skidata.com> Tested-by: Michael Walle <mwalle@kernel.org> Tested-by: Tor Vic <torvic9@mailbox.org> [wsa: removed a comment which needs more work, code is ok] Signed-off-by: Wolfram Sang <wsa@kernel.org>
100 lines
2.9 KiB
C
100 lines
2.9 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
/*
|
|
* i2c-core.h - interfaces internal to the I2C framework
|
|
*/
|
|
|
|
#include <linux/kconfig.h>
|
|
#include <linux/rwsem.h>
|
|
|
|
struct i2c_devinfo {
|
|
struct list_head list;
|
|
int busnum;
|
|
struct i2c_board_info board_info;
|
|
};
|
|
|
|
/* board_lock protects board_list and first_dynamic_bus_num.
|
|
* only i2c core components are allowed to use these symbols.
|
|
*/
|
|
extern struct rw_semaphore __i2c_board_lock;
|
|
extern struct list_head __i2c_board_list;
|
|
extern int __i2c_first_dynamic_bus_num;
|
|
|
|
int i2c_check_7bit_addr_validity_strict(unsigned short addr);
|
|
int i2c_dev_irq_from_resources(const struct resource *resources,
|
|
unsigned int num_resources);
|
|
|
|
/*
|
|
* We only allow atomic transfers for very late communication, e.g. to access a
|
|
* PMIC when powering down. Atomic transfers are a corner case and not for
|
|
* generic use!
|
|
*/
|
|
static inline bool i2c_in_atomic_xfer_mode(void)
|
|
{
|
|
return system_state > SYSTEM_RUNNING &&
|
|
(IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled());
|
|
}
|
|
|
|
static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (i2c_in_atomic_xfer_mode()) {
|
|
WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic,
|
|
"No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev));
|
|
ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN;
|
|
} else {
|
|
i2c_lock_bus(adap, I2C_LOCK_SEGMENT);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static inline int __i2c_check_suspended(struct i2c_adapter *adap)
|
|
{
|
|
if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) {
|
|
if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags))
|
|
dev_WARN(&adap->dev, "Transfer while suspended\n");
|
|
return -ESHUTDOWN;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_ACPI
|
|
void i2c_acpi_register_devices(struct i2c_adapter *adap);
|
|
|
|
int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable);
|
|
#else /* CONFIG_ACPI */
|
|
static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
|
|
|
|
static inline int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_ACPI */
|
|
extern struct notifier_block i2c_acpi_notifier;
|
|
|
|
#ifdef CONFIG_ACPI_I2C_OPREGION
|
|
int i2c_acpi_install_space_handler(struct i2c_adapter *adapter);
|
|
void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter);
|
|
#else /* CONFIG_ACPI_I2C_OPREGION */
|
|
static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; }
|
|
static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { }
|
|
#endif /* CONFIG_ACPI_I2C_OPREGION */
|
|
|
|
#ifdef CONFIG_OF
|
|
void of_i2c_register_devices(struct i2c_adapter *adap);
|
|
#else
|
|
static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
|
|
#endif
|
|
extern struct notifier_block i2c_of_notifier;
|
|
|
|
#if IS_ENABLED(CONFIG_I2C_SMBUS)
|
|
int i2c_setup_smbus_alert(struct i2c_adapter *adap);
|
|
#else
|
|
static inline int i2c_setup_smbus_alert(struct i2c_adapter *adap)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|