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From: H Hartley Sweeten on 20 Apr 2010 19:20
The Read-ID command will continuously output the Manufacture ID and Device ID
until the command is terminated by a low to high transition on the CE# pin.
We can take advantage of this in the sst25l_match_device routine by reading
both bytes in one spi_write_then_read transaction.

Signed-off-by: H Hartley Sweeten <hsweeten(a)visionengravers.com>
Cc: David Woodhouse <dwmw2(a)infradead.org>
Cc: Andre Renaud <andre(a)bluewatersys.com>
Cc: Ryan Mallon <ryan(a)bluewatersys.com>

---

diff --git a/drivers/mtd/devices/sst25l.c b/drivers/mtd/devices/sst25l.c
index fe17054..b13ca75 100644
--- a/drivers/mtd/devices/sst25l.c
+++ b/drivers/mtd/devices/sst25l.c
@@ -328,7 +328,7 @@ out:
static struct flash_info *__init sst25l_match_device(struct spi_device *spi)
{
struct flash_info *flash_info = NULL;
- unsigned char command[4], response;
+ unsigned char command[4], response[2];
int i, err;
uint16_t id;

@@ -336,25 +336,14 @@ static struct flash_info *__init sst25l_match_device(struct spi_device *spi)
command[1] = 0;
command[2] = 0;
command[3] = 0;
- err = spi_write_then_read(spi, command, sizeof(command), &response, 1);
+ err = spi_write_then_read(spi, command, sizeof(command),
+ response, sizeof(response));
if (err < 0) {
dev_err(&spi->dev, "error reading device id msb\n");
return NULL;
}

- id = response << 8;
-
- command[0] = SST25L_CMD_READ_ID;
- command[1] = 0;
- command[2] = 0;
- command[3] = 1;
- err = spi_write_then_read(spi, command, sizeof(command), &response, 1);
- if (err < 0) {
- dev_err(&spi->dev, "error reading device id lsb\n");
- return NULL;
- }
-
- id |= response;
+ id = (response[0] << 8) | response[1];

for (i = 0; i < ARRAY_SIZE(sst25l_flash_info); i++)
if (sst25l_flash_info[i].device_id == id)
 | 
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Next: patch input-wacom-switch-mode-upon-system-resume.patch added to 2.6.33-stable tree