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From 444149f35455bfe551ce9dfa21d00b5b34ffb04f Mon Sep 17 00:00:00 2001
From: Kamal Mostafa <kamal@whence.com>
Date: Mon, 22 Oct 2012 15:52:44 -0700
Subject: [PATCH 046/174] spi/spi-bcm2708: respect per-transfer SPI clock
speed_hz value
The bcm2708 SPI driver's bcm2708_process_transfer() was ignoring the
per-transfer speed_hz value even when it was provided (it always just
used the spi device's max_speed_hz value). Now, per-transfer speed_hz
values are respected.
Also added debug print to bcm2708_setup_state() to help keep an eye on
the configured SPI parameters.
Signed-off-by: Kamal Mostafa <kamal@whence.com>
---
drivers/spi/spi-bcm2708.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/drivers/spi/spi-bcm2708.c
+++ b/drivers/spi/spi-bcm2708.c
@@ -259,6 +259,10 @@ static int bcm2708_setup_state(struct sp
if (state) {
state->cs = cs;
state->cdiv = cdiv;
+ dev_dbg(dev, "setup: want %d Hz; "
+ "bus_hz=%lu / cdiv=%u == %lu Hz; "
+ "mode %u: cs 0x%08X\n",
+ hz, bus_hz, cdiv, bus_hz/cdiv, mode, cs);
}
return 0;
@@ -277,7 +281,8 @@ static int bcm2708_process_transfer(stru
if (xfer->bits_per_word || xfer->speed_hz) {
ret = bcm2708_setup_state(spi->master, &spi->dev, &state,
- spi->max_speed_hz, spi->chip_select, spi->mode,
+ xfer->speed_hz ? xfer->speed_hz : spi->max_speed_hz,
+ spi->chip_select, spi->mode,
spi->bits_per_word);
if (ret)
return ret;
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