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| author | Heiner Kallweit <hkallweit1@gmail.com> | 2022-12-19 19:13:44 +0100 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2023-02-12 22:10:30 +0100 |
| commit | c467d919f0da1c83ebee5087e166cf2bcfbb6f6d (patch) | |
| tree | eada043ea244396676524f65a3b26062b1065eff /drivers/i2c | |
| parent | i2c: st: use pm_sleep_ptr to avoid ifdef CONFIG_PM_SLEEP (diff) | |
| download | linux-c467d919f0da1c83ebee5087e166cf2bcfbb6f6d.tar.xz linux-c467d919f0da1c83ebee5087e166cf2bcfbb6f6d.zip | |
i2c: i801: improve interrupt handler
Not sure if it can happen, but better play safe: If SMBHSTSTS_BYTE_DONE
and an error flag is set, then don't trust the result and skip calling
i801_isr_byte_done(). In addition clear status bit SMBHSTSTS_BYTE_DONE
in the main interrupt handler, this allows to simplify the code a
little.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-i801.c | 25 |
1 files changed, 8 insertions, 17 deletions
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 1fda1eaa6d6a..da773c563e34 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -558,9 +558,6 @@ static void i801_isr_byte_done(struct i801_priv *priv) /* Write next byte, except for IRQ after last byte */ outb_p(priv->data[++priv->count], SMBBLKDAT(priv)); } - - /* Clear BYTE_DONE to continue with next byte */ - outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv)); } static irqreturn_t i801_host_notify_isr(struct i801_priv *priv) @@ -590,7 +587,6 @@ static irqreturn_t i801_host_notify_isr(struct i801_priv *priv) * BUS_ERR - SMI# transaction collision * FAILED - transaction was canceled due to a KILL request * When any of these occur, update ->status and signal completion. - * ->status must be cleared before kicking off the next transaction. * * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt * occurs for each byte of a byte-by-byte to prepare the next byte. @@ -615,23 +611,18 @@ static irqreturn_t i801_isr(int irq, void *dev_id) } status = inb_p(SMBHSTSTS(priv)); - if (status & SMBHSTSTS_BYTE_DONE) + if ((status & (SMBHSTSTS_BYTE_DONE | STATUS_ERROR_FLAGS)) == SMBHSTSTS_BYTE_DONE) i801_isr_byte_done(priv); /* - * Clear remaining IRQ sources: Completion of last command, errors - * and the SMB_ALERT signal. SMB_ALERT status is set after signal - * assertion independently of the interrupt generation being blocked - * or not so clear it always when the status is set. - */ - status &= SMBHSTSTS_INTR | STATUS_ERROR_FLAGS | SMBHSTSTS_SMBALERT_STS; - if (status) - outb_p(status, SMBHSTSTS(priv)); - status &= ~SMBHSTSTS_SMBALERT_STS; /* SMB_ALERT not reported */ - /* - * Report transaction result. - * ->status must be cleared before the next transaction is started. + * Clear IRQ sources: SMB_ALERT status is set after signal assertion + * independently of the interrupt generation being blocked or not + * so clear it always when the status is set. */ + status &= STATUS_FLAGS | SMBHSTSTS_SMBALERT_STS; + outb_p(status, SMBHSTSTS(priv)); + + status &= STATUS_ERROR_FLAGS | SMBHSTSTS_INTR; if (status) { priv->status = status; complete(&priv->done); |