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authorMark Brown <broonie@linaro.org>2013-10-25 12:51:40 +0400
committerMark Brown <broonie@linaro.org>2013-10-25 12:51:40 +0400
commit176c51c1e4fbe04c273d564cf9ccf569606b5fd2 (patch)
tree7ccea0fdae71ecd90c9a3e9712b833b3983cfb2b /drivers/spi/spi-tegra114.c
parentf88df3a72c257d6071641164945ee51b379e1f44 (diff)
parentf4fade12d506e14867a2b0a5e2f7aaf227297d8b (diff)
downloadlinux-176c51c1e4fbe04c273d564cf9ccf569606b5fd2.tar.xz
Merge remote-tracking branch 'spi/topic/tegra114' into spi-next
Diffstat (limited to 'drivers/spi/spi-tegra114.c')
-rw-r--r--drivers/spi/spi-tegra114.c85
1 files changed, 68 insertions, 17 deletions
diff --git a/drivers/spi/spi-tegra114.c b/drivers/spi/spi-tegra114.c
index b3821fb9da3f..9146bb3c2489 100644
--- a/drivers/spi/spi-tegra114.c
+++ b/drivers/spi/spi-tegra114.c
@@ -182,6 +182,7 @@ struct tegra_spi_data {
u32 cur_speed;
struct spi_device *cur_spi;
+ struct spi_device *cs_control;
unsigned cur_pos;
unsigned cur_len;
unsigned words_per_32bit;
@@ -676,15 +677,12 @@ static void tegra_spi_deinit_dma_param(struct tegra_spi_data *tspi,
dma_release_channel(dma_chan);
}
-static int tegra_spi_start_transfer_one(struct spi_device *spi,
- struct spi_transfer *t, bool is_first_of_msg,
- bool is_single_xfer)
+static unsigned long tegra_spi_setup_transfer_one(struct spi_device *spi,
+ struct spi_transfer *t, bool is_first_of_msg)
{
struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master);
u32 speed = t->speed_hz;
u8 bits_per_word = t->bits_per_word;
- unsigned total_fifo_words;
- int ret;
unsigned long command1;
int req_mode;
@@ -698,7 +696,6 @@ static int tegra_spi_start_transfer_one(struct spi_device *spi,
tspi->cur_rx_pos = 0;
tspi->cur_tx_pos = 0;
tspi->curr_xfer = t;
- total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t);
if (is_first_of_msg) {
tegra_spi_clear_status(tspi);
@@ -717,7 +714,12 @@ static int tegra_spi_start_transfer_one(struct spi_device *spi,
else if (req_mode == SPI_MODE_3)
command1 |= SPI_CONTROL_MODE_3;
- tegra_spi_writel(tspi, command1, SPI_COMMAND1);
+ if (tspi->cs_control) {
+ if (tspi->cs_control != spi)
+ tegra_spi_writel(tspi, command1, SPI_COMMAND1);
+ tspi->cs_control = NULL;
+ } else
+ tegra_spi_writel(tspi, command1, SPI_COMMAND1);
command1 |= SPI_CS_SW_HW;
if (spi->mode & SPI_CS_HIGH)
@@ -732,6 +734,18 @@ static int tegra_spi_start_transfer_one(struct spi_device *spi,
command1 |= SPI_BIT_LENGTH(bits_per_word - 1);
}
+ return command1;
+}
+
+static int tegra_spi_start_transfer_one(struct spi_device *spi,
+ struct spi_transfer *t, unsigned long command1)
+{
+ struct tegra_spi_data *tspi = spi_master_get_devdata(spi->master);
+ unsigned total_fifo_words;
+ int ret;
+
+ total_fifo_words = tegra_spi_calculate_curr_xfer_param(spi, tspi, t);
+
if (tspi->is_packed)
command1 |= SPI_PACKED;
@@ -803,29 +817,50 @@ static int tegra_spi_setup(struct spi_device *spi)
return 0;
}
+static void tegra_spi_transfer_delay(int delay)
+{
+ if (!delay)
+ return;
+
+ if (delay >= 1000)
+ mdelay(delay / 1000);
+
+ udelay(delay % 1000);
+}
+
static int tegra_spi_transfer_one_message(struct spi_master *master,
struct spi_message *msg)
{
bool is_first_msg = true;
- int single_xfer;
struct tegra_spi_data *tspi = spi_master_get_devdata(master);
struct spi_transfer *xfer;
struct spi_device *spi = msg->spi;
int ret;
+ bool skip = false;
msg->status = 0;
msg->actual_length = 0;
- single_xfer = list_is_singular(&msg->transfers);
list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ unsigned long cmd1;
+
INIT_COMPLETION(tspi->xfer_completion);
- ret = tegra_spi_start_transfer_one(spi, xfer,
- is_first_msg, single_xfer);
+
+ cmd1 = tegra_spi_setup_transfer_one(spi, xfer, is_first_msg);
+
+ if (!xfer->len) {
+ ret = 0;
+ skip = true;
+ goto complete_xfer;
+ }
+
+ ret = tegra_spi_start_transfer_one(spi, xfer, cmd1);
if (ret < 0) {
dev_err(tspi->dev,
"spi can not start transfer, err %d\n", ret);
- goto exit;
+ goto complete_xfer;
}
+
is_first_msg = false;
ret = wait_for_completion_timeout(&tspi->xfer_completion,
SPI_DMA_TIMEOUT);
@@ -833,24 +868,40 @@ static int tegra_spi_transfer_one_message(struct spi_master *master,
dev_err(tspi->dev,
"spi trasfer timeout, err %d\n", ret);
ret = -EIO;
- goto exit;
+ goto complete_xfer;
}
if (tspi->tx_status || tspi->rx_status) {
dev_err(tspi->dev, "Error in Transfer\n");
ret = -EIO;
- goto exit;
+ goto complete_xfer;
}
msg->actual_length += xfer->len;
- if (xfer->cs_change && xfer->delay_usecs) {
+
+complete_xfer:
+ if (ret < 0 || skip) {
tegra_spi_writel(tspi, tspi->def_command1_reg,
SPI_COMMAND1);
- udelay(xfer->delay_usecs);
+ tegra_spi_transfer_delay(xfer->delay_usecs);
+ goto exit;
+ } else if (msg->transfers.prev == &xfer->transfer_list) {
+ /* This is the last transfer in message */
+ if (xfer->cs_change)
+ tspi->cs_control = spi;
+ else {
+ tegra_spi_writel(tspi, tspi->def_command1_reg,
+ SPI_COMMAND1);
+ tegra_spi_transfer_delay(xfer->delay_usecs);
+ }
+ } else if (xfer->cs_change) {
+ tegra_spi_writel(tspi, tspi->def_command1_reg,
+ SPI_COMMAND1);
+ tegra_spi_transfer_delay(xfer->delay_usecs);
}
+
}
ret = 0;
exit:
- tegra_spi_writel(tspi, tspi->def_command1_reg, SPI_COMMAND1);
msg->status = ret;
spi_finalize_current_message(master);
return ret;