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authorOlof Johansson <olof@lixom.net>2012-09-20 19:57:38 -0700
committerOlof Johansson <olof@lixom.net>2012-09-20 19:57:38 -0700
commit32dec75349da4e68b53f099ce3a96469cdc334d6 (patch)
tree96aca7914b07697668ec716a3f80fb8c82e7a971 /drivers/i2c/busses/i2c-pnx.c
parent740418ef19fd7def7b9c333435d4ca1dce28cc42 (diff)
parent9891e3240543c45176b1298164418b61e8909ed0 (diff)
Merge tag 'tegra-for-3.7-dmaengine' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/cleanup
ARM: tegra: switch to dmaengine The Tegra code-base has contained both a legacy DMA and a dmaengine driver since v3.6-rcX. This series flips Tegra's defconfig to enable dmaengine rather than the legacy driver, and removes the legacy driver and all client code. * tag 'tegra-for-3.7-dmaengine' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: ASoC: tegra: remove support of legacy DMA driver based access spi: tegra: remove support of legacy DMA driver based access ARM: tegra: apbio: remove support of legacy DMA driver based access ARM: tegra: dma: remove legacy APB DMA driver ARM: tegra: config: enable dmaengine based APB DMA driver + sync to 3.6-rc6
Diffstat (limited to 'drivers/i2c/busses/i2c-pnx.c')
-rw-r--r--drivers/i2c/busses/i2c-pnx.c53
1 files changed, 31 insertions, 22 deletions
diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c
index 5d54416770b..8488bddfe46 100644
--- a/drivers/i2c/busses/i2c-pnx.c
+++ b/drivers/i2c/busses/i2c-pnx.c
@@ -48,8 +48,9 @@ enum {
mcntrl_afie = 0x00000002,
mcntrl_naie = 0x00000004,
mcntrl_drmie = 0x00000008,
- mcntrl_daie = 0x00000020,
- mcntrl_rffie = 0x00000040,
+ mcntrl_drsie = 0x00000010,
+ mcntrl_rffie = 0x00000020,
+ mcntrl_daie = 0x00000040,
mcntrl_tffie = 0x00000080,
mcntrl_reset = 0x00000100,
mcntrl_cdbmode = 0x00000400,
@@ -290,31 +291,37 @@ static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data)
* or we didn't 'ask' for it yet.
*/
if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
- dev_dbg(&alg_data->adapter.dev,
- "%s(): Write dummy data to fill Rx-fifo...\n",
- __func__);
+ /* 'Asking' is done asynchronously, e.g. dummy TX of several
+ * bytes is done before the first actual RX arrives in FIFO.
+ * Therefore, ordered bytes (via TX) are counted separately.
+ */
+ if (alg_data->mif.order) {
+ dev_dbg(&alg_data->adapter.dev,
+ "%s(): Write dummy data to fill Rx-fifo...\n",
+ __func__);
- if (alg_data->mif.len == 1) {
- /* Last byte, do not acknowledge next rcv. */
- val |= stop_bit;
+ if (alg_data->mif.order == 1) {
+ /* Last byte, do not acknowledge next rcv. */
+ val |= stop_bit;
+
+ /*
+ * Enable interrupt RFDAIE (data in Rx fifo),
+ * and disable DRMIE (need data for Tx)
+ */
+ ctl = ioread32(I2C_REG_CTL(alg_data));
+ ctl |= mcntrl_rffie | mcntrl_daie;
+ ctl &= ~mcntrl_drmie;
+ iowrite32(ctl, I2C_REG_CTL(alg_data));
+ }
/*
- * Enable interrupt RFDAIE (data in Rx fifo),
- * and disable DRMIE (need data for Tx)
+ * Now we'll 'ask' for data:
+ * For each byte we want to receive, we must
+ * write a (dummy) byte to the Tx-FIFO.
*/
- ctl = ioread32(I2C_REG_CTL(alg_data));
- ctl |= mcntrl_rffie | mcntrl_daie;
- ctl &= ~mcntrl_drmie;
- iowrite32(ctl, I2C_REG_CTL(alg_data));
+ iowrite32(val, I2C_REG_TX(alg_data));
+ alg_data->mif.order--;
}
-
- /*
- * Now we'll 'ask' for data:
- * For each byte we want to receive, we must
- * write a (dummy) byte to the Tx-FIFO.
- */
- iowrite32(val, I2C_REG_TX(alg_data));
-
return 0;
}
@@ -514,6 +521,7 @@ i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
alg_data->mif.buf = pmsg->buf;
alg_data->mif.len = pmsg->len;
+ alg_data->mif.order = pmsg->len;
alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ?
I2C_SMBUS_READ : I2C_SMBUS_WRITE;
alg_data->mif.ret = 0;
@@ -566,6 +574,7 @@ i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
/* Cleanup to be sure... */
alg_data->mif.buf = NULL;
alg_data->mif.len = 0;
+ alg_data->mif.order = 0;
dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n",
__func__, ioread32(I2C_REG_STS(alg_data)));