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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 09:30:52 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 09:30:52 -0700 |
commit | b324c67d4800e59171f48d9ddab6cbfb59110482 (patch) | |
tree | a16509a710e76fa24c01514b60aed06b7db13716 /arch/arm/plat-spear/pl080.c | |
parent | 8dca6010d44cc722a94dc6da96560f9083dac782 (diff) | |
parent | 396d81cd0fe12ce5d1f6d159f093f9315d2837bc (diff) | |
download | linux-b324c67d4800e59171f48d9ddab6cbfb59110482.tar.bz2 |
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.c | 80 |
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); +} |