[PATCH 2/5 v2] spi-topcliff-pch: Fix SSN Control issue

From: Tomoya MORINAGA
Date: Tue Sep 06 2011 - 04:18:28 EST


During processing 1 command/data series,
SSN should keep LOW.
However, currently, SSN becomes HIGH.
This patch fixes the issue.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@xxxxxxxxxxxxxxx>
---
v2: v1 patch series are included invalid patch file
---
drivers/spi/spi-topcliff-pch.c | 10 +++-------
1 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c
index 7a98caa..c36d516 100644
--- a/drivers/spi/spi-topcliff-pch.c
+++ b/drivers/spi/spi-topcliff-pch.c
@@ -58,6 +58,7 @@
#define PCH_SLEEP_TIME 10

#define SSN_LOW 0x02U
+#define SSN_HIGH 0x03U
#define SSN_NO_CONTROL 0x00U
#define PCH_MAX_CS 0xFF
#define PCI_DEVICE_ID_GE_SPI 0x8816
@@ -756,10 +757,6 @@ static void pch_spi_set_ir(struct pch_spi_data *data)

wait_event_interruptible(data->wait, data->transfer_complete);

- pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
- dev_dbg(&data->master->dev,
- "%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
-
/* clear all interrupts */
pch_spi_writereg(data->master, PCH_SPSR,
pch_spi_readreg(data->master, PCH_SPSR));
@@ -848,9 +845,6 @@ static void pch_spi_start_transfer(struct pch_spi_data *data)
kfree(dma->sg_rx_p);

spin_lock_irqsave(&data->lock, flags);
- pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
- dev_dbg(&data->master->dev,
- "%s:no more control over SSN-writing 0 to SSNXCR.", __func__);

/* clear fifo threshold, disable interrupts, disable SPI transfer */
pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
@@ -1167,6 +1161,7 @@ static void pch_spi_process_messages(struct work_struct *pwork)
if (data->use_dma)
pch_spi_request_dma(data,
data->current_msg->spi->bits_per_word);
+ pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
do {
/* If we are already processing a message get the next
transfer structure from the message otherwise retrieve
@@ -1227,6 +1222,7 @@ static void pch_spi_process_messages(struct work_struct *pwork)

} while (data->cur_trans != NULL);

+ pch_spi_writereg(data->master, PCH_SSNXCR, SSN_HIGH);
if (data->use_dma)
pch_spi_release_dma(data);
}
--
1.7.4.4

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