summaryrefslogtreecommitdiff
path: root/arch/arm/plat-spear/pl080.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-22 20:30:52 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-22 20:30:52 +0400
commitb324c67d4800e59171f48d9ddab6cbfb59110482 (patch)
treea16509a710e76fa24c01514b60aed06b7db13716 /arch/arm/plat-spear/pl080.c
parent8dca6010d44cc722a94dc6da96560f9083dac782 (diff)
parent396d81cd0fe12ce5d1f6d159f093f9315d2837bc (diff)
downloadlinux-b324c67d4800e59171f48d9ddab6cbfb59110482.tar.xz
Merge tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull device tree conversions for arm-soc, part 1, from Olof Johansson: "The spear3xx, lpc32xx, shmobile and mmp platforms are joining the game of booting using device trees, which is a great step forward for them. at91 and spear have pretty much completed this process with a huge amount of work being put into at91. The other platforms are continuing the process. We finally start to see the payback on this investment, as new machines are getting supported purely by adding a .dts source file that can be completely independent of the kernel source." Fix up trivial conflict in arch/arm/Kconfig * tag 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (83 commits) ARM: at91: Add ADC driver to at91sam9260/at91sam9g20 dtsi files arm/dts: omap4-panda: Add LEDs support arm/dts: omap4-sdp: Add LEDs support arm/dts: twl4030: Add twl4030-gpio node OMAP4: devices: Do not create mcpdm device if the dtb has been provided OMAP4: devices: Do not create dmic device if the dtb has been provided Documentation: update docs for mmp dt ARM: dts: refresh dts file for arch mmp ARM: mmp: support pxa910 with device tree ARM: mmp: support mmp2 with device tree gpio: pxa: parse gpio from DTS file ARM: mmp: support DT in timer ARM: mmp: support DT in irq ARM: mmp: append CONFIG_MACH_MMP2_DT ARM: mmp: fix build issue on mmp with device tree ARM: ux500: Enable PRCMU Timer 4 (clocksource) for Device Tree ARM: ux500: Disable SMSC911x platform code registration when DT is enabled ARM: ux500: Fork cpu-db8500 platform_devs for sequential DT enablement ARM: ux500: Do not attempt to register non-existent i2c devices on Snowball ARM: SPEAr3xx: Correct keyboard data passed from DT ...
Diffstat (limited to 'arch/arm/plat-spear/pl080.c')
-rw-r--r--arch/arm/plat-spear/pl080.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/arm/plat-spear/pl080.c b/arch/arm/plat-spear/pl080.c
new file mode 100644
index 000000000000..a56a067717c1
--- /dev/null
+++ b/arch/arm/plat-spear/pl080.c
@@ -0,0 +1,80 @@
+/*
+ * 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/spear.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);
+}