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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-03-15 14:16:28 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-03-15 14:16:28 -0700 |
| commit | 51b1ac0fa2403d1db009189122c17b7c1ea37b33 (patch) | |
| tree | b92e7ad8ca4d9cf40cbed1ee1c3a794e44d71cb4 /drivers/i2c/i2c-core-base.c | |
| parent | 2dbb0e6c1961d823354c12bc1b66b005d1c78092 (diff) | |
| parent | cd86d1403bb4c80e443d736b2a692cbf68a9f471 (diff) | |
Merge branch 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fixes from Wolfram Sang:
"A set of driver bugfixes and an improvement for a core helper"
* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: i2c-designware-platdrv: Always use a dynamic adapter number
i2c: i2c-designware-platdrv: Cleanup setting of the adapter number
i2c: add extra check to safe DMA buffer helper
i2c: i2c-stm32f7: Fix SDADEL minimum formula
i2c: rcar: explain the lockless design
i2c: rcar: fix concurrency issue related to ICDMAER
i2c: sis630: correct format strings
i2c: mediatek: modify threshold passed to i2c_get_dma_safe_msg_buf()
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) |