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| author | David S. Miller <davem@davemloft.net> | 2019-03-27 17:37:58 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-03-27 17:37:58 -0700 |
| commit | 356d71e00d278d865f8c7f68adebd6ce4698a7e2 (patch) | |
| tree | 8cb2dabf7440b56c6dee76b4253210c6b603b98e /drivers/i2c/i2c-core-base.c | |
| parent | df453700e8d81b1bdafdf684365ee2b9431fb702 (diff) | |
| parent | 1a9df9e29c2afecf6e3089442d429b377279ca3c (diff) | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Diffstat (limited to 'drivers/i2c/i2c-core-base.c')
| -rw-r--r-- | drivers/i2c/i2c-core-base.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index cb6c5cb0df0b..38af18645133 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -2258,7 +2258,8 @@ EXPORT_SYMBOL(i2c_put_adapter); /** * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg * @msg: the message to be checked - * @threshold: the minimum number of bytes for which using DMA makes sense + * @threshold: the minimum number of bytes for which using DMA makes sense. + * Should at least be 1. * * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. * Or a valid pointer to be used with DMA. After use, release it by @@ -2268,7 +2269,11 @@ EXPORT_SYMBOL(i2c_put_adapter); */ u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) { - if (msg->len < threshold) + /* also skip 0-length msgs for bogus thresholds of 0 */ + if (!threshold) + pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", + msg->addr); + if (msg->len < threshold || msg->len == 0) return NULL; if (msg->flags & I2C_M_DMA_SAFE) |