[PATCH 3/3] i3c: mipi-i3c-hci: Use own DMA bounce buffer management for I2C transfers
Jarkko Nikula
jarkko.nikula at linux.intel.com
Wed Jun 4 05:55:13 PDT 2025
Stop using I2C DMA-safe API for two reasons:
- Not needed if driver is using PIO mode.
- DMA transfers needs a properly sized receive bounce buffer when the
device DMA is IOMMU mapped causing needless double bounce buffering in
that case.
Cc: Billy Tsai <billy_tsai at aspeedtech.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula at linux.intel.com>
---
drivers/i3c/master/mipi-i3c-hci/core.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
index 24c5e7d5b439..fa4c0b826345 100644
--- a/drivers/i3c/master/mipi-i3c-hci/core.c
+++ b/drivers/i3c/master/mipi-i3c-hci/core.c
@@ -348,7 +348,7 @@ static int i3c_hci_i2c_xfers(struct i2c_dev_desc *dev,
return -ENOMEM;
for (i = 0; i < nxfers; i++) {
- xfer[i].data = i2c_get_dma_safe_msg_buf(&i2c_xfers[i], 1);
+ xfer[i].data = i2c_xfers[i].buf;
xfer[i].data_len = i2c_xfers[i].len;
xfer[i].rnw = i2c_xfers[i].flags & I2C_M_RD;
hci->cmd->prep_i2c_xfer(hci, dev, &xfer[i]);
@@ -374,10 +374,6 @@ static int i3c_hci_i2c_xfers(struct i2c_dev_desc *dev,
}
out:
- for (i = 0; i < nxfers; i++)
- i2c_put_dma_safe_msg_buf(xfer[i].data, &i2c_xfers[i],
- ret ? false : true);
-
hci_free_xfer(xfer, nxfers);
return ret;
}
--
2.47.2
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