lkml.org 
[lkml]   [2007]   [Oct]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/9] Blackfin SPI driver: Blackfin SPI driver does not respect the per-transfer cs_change field
Date
Add cs_active/cs_deactive functions and try to catch the cs_change flag.

Signed-off-by: Bryan Wu <bryan.wu@analog.com>
---
drivers/spi/spi_bfin5xx.c | 76 ++++++++++++++++++++++++++++++++-------------
1 files changed, 54 insertions(+), 22 deletions(-)

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index 2f46283..7093065 100644
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -115,6 +115,7 @@ struct driver_data {
size_t rx_map_len;
size_t tx_map_len;
u8 n_bytes;
+ int cs_change;
void (*write) (struct driver_data *);
void (*read) (struct driver_data *);
void (*duplex) (struct driver_data *);
@@ -179,6 +180,26 @@ static int flush(struct driver_data *drv_data)
return limit;
}

+/* Chip select operation functions for cs_change flag */
+static void cs_active(struct chip_data *chip)
+{
+ u16 flag = read_FLAG();
+
+ flag |= chip->flag;
+ flag &= ~(chip->flag << 8);
+
+ write_FLAG(flag);
+}
+
+static void cs_deactive(struct chip_data *chip)
+{
+ u16 flag = read_FLAG();
+
+ flag |= (chip->flag << 8);
+
+ write_FLAG(flag);
+}
+
#define MAX_SPI0_SSEL 7

/* stop controller and re-config current chip*/
@@ -198,7 +219,7 @@ static int restore_state(struct driver_data *drv_data)
/* Load the registers */
write_CTRL(chip->ctl_reg);
write_BAUD(chip->baud);
- write_FLAG(chip->flag);
+ cs_active(chip);

if (!chip->chip_select_requested) {
int i = chip->chip_select_num;
@@ -273,20 +294,20 @@ static void u8_cs_chg_writer(struct driver_data *drv_data)
struct chip_data *chip = drv_data->cur_chip;

while (drv_data->tx < drv_data->tx_end) {
- write_FLAG(chip->flag);
+ cs_active(chip);

write_TDBR(*(u8 *) (drv_data->tx));
while (read_STAT() & BIT_STAT_TXS)
continue;
while (!(read_STAT() & BIT_STAT_SPIF))
continue;
- write_FLAG(0xFF00 | chip->flag);
+ cs_deactive(chip);

if (chip->cs_chg_udelay)
udelay(chip->cs_chg_udelay);
++drv_data->tx;
}
- write_FLAG(0xFF00);
+ cs_deactive(chip);

}

@@ -318,7 +339,7 @@ static void u8_cs_chg_reader(struct driver_data *drv_data)
struct chip_data *chip = drv_data->cur_chip;

while (drv_data->rx < drv_data->rx_end) {
- write_FLAG(chip->flag);
+ cs_active(chip);

read_RDBR(); /* kick off */
while (!(read_STAT() & BIT_STAT_RXS))
@@ -326,13 +347,13 @@ static void u8_cs_chg_reader(struct driver_data *drv_data)
while (!(read_STAT() & BIT_STAT_SPIF))
continue;
*(u8 *) (drv_data->rx) = read_SHAW();
- write_FLAG(0xFF00 | chip->flag);
+ cs_deactive(chip);

if (chip->cs_chg_udelay)
udelay(chip->cs_chg_udelay);
++drv_data->rx;
}
- write_FLAG(0xFF00);
+ cs_deactive(chip);

}

@@ -356,7 +377,7 @@ static void u8_cs_chg_duplex(struct driver_data *drv_data)
struct chip_data *chip = drv_data->cur_chip;

while (drv_data->rx < drv_data->rx_end) {
- write_FLAG(chip->flag);
+ cs_active(chip);


write_TDBR(*(u8 *) (drv_data->tx));
@@ -365,15 +386,14 @@ static void u8_cs_chg_duplex(struct driver_data *drv_data)
while (!(read_STAT() & BIT_STAT_RXS))
continue;
*(u8 *) (drv_data->rx) = read_RDBR();
- write_FLAG(0xFF00 | chip->flag);
+ cs_deactive(chip);

if (chip->cs_chg_udelay)
udelay(chip->cs_chg_udelay);
++drv_data->rx;
++drv_data->tx;
}
- write_FLAG(0xFF00);
-
+ cs_deactive(chip);
}

static void u16_writer(struct driver_data *drv_data)
@@ -398,20 +418,20 @@ static void u16_cs_chg_writer(struct driver_data *drv_data)
struct chip_data *chip = drv_data->cur_chip;

while (drv_data->tx < drv_data->tx_end) {
- write_FLAG(chip->flag);
+ cs_active(chip);

write_TDBR(*(u16 *) (drv_data->tx));
while ((read_STAT() & BIT_STAT_TXS))
continue;
while (!(read_STAT() & BIT_STAT_SPIF))
continue;
- write_FLAG(0xFF00 | chip->flag);
+ cs_deactive(chip);

if (chip->cs_chg_udelay)
udelay(chip->cs_chg_udelay);
drv_data->tx += 2;
}
- write_FLAG(0xFF00);
+ cs_deactive(chip);
}

static void u16_reader(struct driver_data *drv_data)
@@ -438,7 +458,7 @@ static void u16_cs_chg_reader(struct driver_data *drv_data)
struct chip_data *chip = drv_data->cur_chip;

while (drv_data->rx < drv_data->rx_end) {
- write_FLAG(chip->flag);
+ cs_active(chip);

read_RDBR(); /* kick off */
while (!(read_STAT() & BIT_STAT_RXS))
@@ -446,13 +466,13 @@ static void u16_cs_chg_reader(struct driver_data *drv_data)
while (!(read_STAT() & BIT_STAT_SPIF))
continue;
*(u16 *) (drv_data->rx) = read_SHAW();
- write_FLAG(0xFF00 | chip->flag);
+ cs_deactive(chip);

if (chip->cs_chg_udelay)
udelay(chip->cs_chg_udelay);
drv_data->rx += 2;
}
- write_FLAG(0xFF00);
+ cs_deactive(chip);
}

static void u16_duplex(struct driver_data *drv_data)
@@ -475,7 +495,7 @@ static void u16_cs_chg_duplex(struct driver_data *drv_data)
struct chip_data *chip = drv_data->cur_chip;

while (drv_data->tx < drv_data->tx_end) {
- write_FLAG(chip->flag);
+ cs_active(chip);

write_TDBR(*(u16 *) (drv_data->tx));
while (!(read_STAT() & BIT_STAT_SPIF))
@@ -483,14 +503,14 @@ static void u16_cs_chg_duplex(struct driver_data *drv_data)
while (!(read_STAT() & BIT_STAT_RXS))
continue;
*(u16 *) (drv_data->rx) = read_RDBR();
- write_FLAG(0xFF00 | chip->flag);
+ cs_deactive(chip);

if (chip->cs_chg_udelay)
udelay(chip->cs_chg_udelay);
drv_data->rx += 2;
drv_data->tx += 2;
}
- write_FLAG(0xFF00);
+ cs_deactive(chip);
}

/* test if ther is more transfer to be done */
@@ -515,6 +535,7 @@ static void *next_transfer(struct driver_data *drv_data)
*/
static void giveback(struct driver_data *drv_data)
{
+ struct chip_data *chip = drv_data->cur_chip;
struct spi_transfer *last_transfer;
unsigned long flags;
struct spi_message *msg;
@@ -534,10 +555,13 @@ static void giveback(struct driver_data *drv_data)

/* disable chip select signal. And not stop spi in autobuffer mode */
if (drv_data->tx_dma != 0xFFFF) {
- write_FLAG(0xFF00);
+ cs_deactive(chip);
bfin_spi_disable(drv_data);
}

+ if (!drv_data->cs_change)
+ cs_deactive(chip);
+
if (msg->complete)
msg->complete(msg->context);
}
@@ -546,6 +570,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
{
struct driver_data *drv_data = (struct driver_data *)dev_id;
struct spi_message *msg = drv_data->cur_msg;
+ struct chip_data *chip = drv_data->cur_chip;

dev_dbg(&drv_data->pdev->dev, "in dma_irq_handler\n");
clear_dma_irqstat(CH_SPI);
@@ -573,6 +598,9 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)

msg->actual_length += drv_data->len_in_bytes;

+ if (drv_data->cs_change)
+ cs_deactive(chip);
+
/* Move to next transfer */
msg->state = next_transfer(drv_data);

@@ -659,6 +687,7 @@ static void pump_transfers(unsigned long data)
drv_data->rx_dma = transfer->rx_dma;
drv_data->tx_dma = transfer->tx_dma;
drv_data->len_in_bytes = transfer->len;
+ drv_data->cs_change = transfer->cs_change;

width = chip->width;
if (width == CFG_SPI_WORDSIZE16) {
@@ -683,7 +712,7 @@ static void pump_transfers(unsigned long data)
} else {
write_BAUD(chip->baud);
}
- write_FLAG(chip->flag);
+ cs_active(chip);

dev_dbg(&drv_data->pdev->dev,
"now pumping a transfer: width is %d, len is %d\n",
@@ -834,6 +863,9 @@ static void pump_transfers(unsigned long data)
/* Update total byte transfered */
message->actual_length += drv_data->len;

+ if (drv_data->cs_change)
+ cs_deactive(chip);
+
/* Move to next transfer of this msg */
message->state = next_transfer(drv_data);
}
--
1.5.3.4
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2007-10-11 12:15    [W:0.065 / U:18.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site