From 89c05372d08f3982eeb94d1ea22a60a5eaa8cd6d Mon Sep 17 00:00:00 2001
From: Tero Kristo <tero.kristo@nokia.com>
Date: Tue, 22 Sep 2009 16:46:17 -0700
Subject: [PATCH] spi: McSPI saves CHCONFx too
Previous restore was lazy and only restored CHxCONF when it was needed by
a specific chip select. This could cause occasional errors on an SPI bus
where multiple chip selects are in use.
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
drivers/spi/omap2_mcspi.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c
index e96ad27095654..85b7aea733745 100644
--- a/drivers/spi/omap2_mcspi.c
+++ b/drivers/spi/omap2_mcspi.c
@@ -134,6 +134,7 @@ struct omap2_mcspi_cs {
void __iomem *base;
unsigned long phys;
int word_len;
+ struct list_head node;
/* Context save and restore shadow register */
u32 chconf0;
};
@@ -145,6 +146,7 @@ struct omap2_mcspi_regs {
u32 sysconfig;
u32 modulctrl;
u32 wakeupenable;
+ struct list_head cs;
};
static struct omap2_mcspi_regs omap2_mcspi_ctx[OMAP2_MCSPI_MAX_CTRL];
@@ -255,6 +257,7 @@ static void omap2_mcspi_set_master_mode(struct spi_master *master)
static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
{
struct spi_master *spi_cntrl;
+ struct omap2_mcspi_cs *cs;
spi_cntrl = mcspi->master;
/* McSPI: context restore */
@@ -266,6 +269,10 @@ static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi)
mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE,
omap2_mcspi_ctx[spi_cntrl->bus_num - 1].wakeupenable);
+
+ list_for_each_entry(cs, &omap2_mcspi_ctx[spi_cntrl->bus_num - 1].cs,
+ node)
+ __raw_writel(cs->chconf0, cs->base + OMAP2_MCSPI_CHCONF0);
}
static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi)
{
@@ -714,6 +721,9 @@ static int omap2_mcspi_setup(struct spi_device *spi)
cs->phys = mcspi->phys + spi->chip_select * 0x14;
cs->chconf0 = 0;
spi->controller_state = cs;
+ /* Link this to context save list */
+ list_add_tail(&cs->node,
+ &omap2_mcspi_ctx[mcspi->master->bus_num - 1].cs);
}
if (mcspi_dma->dma_rx_channel == -1
@@ -736,10 +746,15 @@ static void omap2_mcspi_cleanup(struct spi_device *spi)
{
struct omap2_mcspi *mcspi;
struct omap2_mcspi_dma *mcspi_dma;
+ struct omap2_mcspi_cs *cs;
mcspi = spi_master_get_devdata(spi->master);
mcspi_dma = &mcspi->dma_channels[spi->chip_select];
+ /* Unlink controller state from context save list */
+ cs = spi->controller_state;
+ list_del(&cs->node);
+
kfree(spi->controller_state);
if (mcspi_dma->dma_rx_channel != -1) {
@@ -1104,6 +1119,7 @@ static int __init omap2_mcspi_probe(struct platform_device *pdev)
spin_lock_init(&mcspi->lock);
INIT_LIST_HEAD(&mcspi->msg_queue);
+ INIT_LIST_HEAD(&omap2_mcspi_ctx[master->bus_num - 1].cs);
mcspi->ick = clk_get(&pdev->dev, "ick");
if (IS_ERR(mcspi->ick)) {
--
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