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authorArnd Bergmann <arnd@arndb.de>2012-05-14 15:33:42 +0200
committerArnd Bergmann <arnd@arndb.de>2012-05-14 15:33:42 +0200
commitd2819f80d465672b09c2f4cb52303b7f951c4d0f (patch)
treeaa0262703e86b97ad1460c722e78d7233e24e3bb /arch/arm/plat-spear/pl080.c
parent5df33a62c4a028d6fc7f2dcc159827d09b7334b8 (diff)
parent366695ff706669d40459174b1cbb78fca42f4e06 (diff)
Merge branch 'spear/pinctrl' into spear/clock
Conflicts: arch/arm/mach-spear3xx/Makefile arch/arm/mach-spear3xx/clock.c arch/arm/mach-spear3xx/include/mach/generic.h arch/arm/mach-spear6xx/clock.c arch/arm/plat-spear/Makefile drivers/pinctrl/core.c This resolves some annoying merge conflicts. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm/plat-spear/pl080.c')
-rw-r--r--arch/arm/plat-spear/pl080.c79
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/arm/plat-spear/pl080.c b/arch/arm/plat-spear/pl080.c
new file mode 100644
index 00000000000..d53d75e1af5
--- /dev/null
+++ b/arch/arm/plat-spear/pl080.c
@@ -0,0 +1,79 @@
+/*
+ * arch/arm/plat-spear/pl080.c
+ *
+ * DMAC pl080 definitions for SPEAr platform
+ *
+ * Copyright (C) 2012 ST Microelectronics
+ * Viresh Kumar <viresh.kumar@st.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/amba/pl08x.h>
+#include <linux/amba/bus.h>
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/spinlock_types.h>
+#include <mach/misc_regs.h>
+
+static spinlock_t lock = __SPIN_LOCK_UNLOCKED(x);
+
+struct {
+ unsigned char busy;
+ unsigned char val;
+} signals[16] = {{0, 0}, };
+
+int pl080_get_signal(struct pl08x_dma_chan *ch)
+{
+ const struct pl08x_channel_data *cd = ch->cd;
+ unsigned int signal = cd->min_signal, val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&lock, flags);
+
+ /* Return if signal is already acquired by somebody else */
+ if (signals[signal].busy &&
+ (signals[signal].val != cd->muxval)) {
+ spin_unlock_irqrestore(&lock, flags);
+ return -EBUSY;
+ }
+
+ /* If acquiring for the first time, configure it */
+ if (!signals[signal].busy) {
+ val = readl(DMA_CHN_CFG);
+
+ /*
+ * Each request line has two bits in DMA_CHN_CFG register. To
+ * goto the bits of current request line, do left shift of
+ * value by 2 * signal number.
+ */
+ val &= ~(0x3 << (signal * 2));
+ val |= cd->muxval << (signal * 2);
+ writel(val, DMA_CHN_CFG);
+ }
+
+ signals[signal].busy++;
+ signals[signal].val = cd->muxval;
+ spin_unlock_irqrestore(&lock, flags);
+
+ return signal;
+}
+
+void pl080_put_signal(struct pl08x_dma_chan *ch)
+{
+ const struct pl08x_channel_data *cd = ch->cd;
+ unsigned long flags;
+
+ spin_lock_irqsave(&lock, flags);
+
+ /* if signal is not used */
+ if (!signals[cd->min_signal].busy)
+ BUG();
+
+ signals[cd->min_signal].busy--;
+
+ spin_unlock_irqrestore(&lock, flags);
+}