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authorLinus Torvalds <torvalds@linux-foundation.org>2012-03-28 01:41:24 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2012-03-28 01:41:24 +0200
commit34800598b2eebe061445216473b1e4c2ff5cba99 (patch)
treea6d0eb6fe45d9480888d7ddb34840e172ed80e56 /arch/arm/mach-tegra/apbio.c
parentMerge tag 'rpmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc (diff)
parentMerge tag 'regulator-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/br... (diff)
downloadlinux-34800598b2eebe061445216473b1e4c2ff5cba99.tar.xz
linux-34800598b2eebe061445216473b1e4c2ff5cba99.zip
Merge tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull "ARM: driver specific updates" from Arnd Bergmann: "These are all specific to some driver. They are typically the platform side of a change in the drivers directory, such as adding a new driver or extending the interface to the platform. In cases where there is no maintainer for the driver, or the maintainer prefers to have the platform changes in the same branch as the driver changes, the patches to the drivers are included as well. A much smaller set of driver updates that depend on other branches getting merged first will be sent later. The new export of tegra_chip_uid conflicts with other changes in fuse.c. In rtc-sa1100.c, the global removal of IRQF_DISABLED conflicts with the cleanup of the interrupt handling of that driver. Signed-off-by: Arnd Bergmann <arnd@arndb.de>" Fixed up aforementioned trivial conflicts. * tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (94 commits) ARM: SAMSUNG: change the name from s3c-sdhci to exynos4-sdhci mmc: sdhci-s3c: add platform data for the second capability ARM: SAMSUNG: support the second capability for samsung-soc ARM: EXYNOS: add support DMA for EXYNOS4X12 SoC ARM: EXYNOS: Add apb_pclk clkdev entry for mdma1 ARM: EXYNOS: Enable MDMA driver regulator: Remove bq24022 regulator driver rtc: sa1100: add OF support pxa: magician/hx4700: Convert to gpio-regulator from bq24022 ARM: OMAP3+: SmartReflex: fix error handling ARM: OMAP3+: SmartReflex: fix the use of debugfs_create_* API ARM: OMAP3+: SmartReflex: micro-optimization for sanity check ARM: OMAP3+: SmartReflex: misc cleanups ARM: OMAP3+: SmartReflex: move late_initcall() closer to its argument ARM: OMAP3+: SmartReflex: add missing platform_set_drvdata() ARM: OMAP3+: hwmod: add SmartReflex IRQs ARM: OMAP3+: SmartReflex: clear ERRCONFIG_VPBOUNDINTST only on a need ARM: OMAP3+: SmartReflex: Fix status masking in ERRCONFIG register ARM: OMAP3+: SmartReflex: Add a shutdown hook ARM: OMAP3+: SmartReflex Class3: disable errorgen before disable VP ... Conflicts: arch/arm/mach-tegra/Makefile arch/arm/mach-tegra/fuse.c drivers/rtc/rtc-sa1100.c
Diffstat (limited to 'arch/arm/mach-tegra/apbio.c')
-rw-r--r--arch/arm/mach-tegra/apbio.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/apbio.c b/arch/arm/mach-tegra/apbio.c
new file mode 100644
index 000000000000..e75451e517bd
--- /dev/null
+++ b/arch/arm/mach-tegra/apbio.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2010 NVIDIA Corporation.
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/dma-mapping.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/sched.h>
+#include <linux/mutex.h>
+
+#include <mach/dma.h>
+#include <mach/iomap.h>
+
+#include "apbio.h"
+
+static DEFINE_MUTEX(tegra_apb_dma_lock);
+
+static struct tegra_dma_channel *tegra_apb_dma;
+static u32 *tegra_apb_bb;
+static dma_addr_t tegra_apb_bb_phys;
+static DECLARE_COMPLETION(tegra_apb_wait);
+
+bool tegra_apb_init(void)
+{
+ struct tegra_dma_channel *ch;
+
+ mutex_lock(&tegra_apb_dma_lock);
+
+ /* Check to see if we raced to setup */
+ if (tegra_apb_dma)
+ goto out;
+
+ ch = tegra_dma_allocate_channel(TEGRA_DMA_MODE_ONESHOT |
+ TEGRA_DMA_SHARED);
+
+ if (!ch)
+ goto out_fail;
+
+ tegra_apb_bb = dma_alloc_coherent(NULL, sizeof(u32),
+ &tegra_apb_bb_phys, GFP_KERNEL);
+ if (!tegra_apb_bb) {
+ pr_err("%s: can not allocate bounce buffer\n", __func__);
+ tegra_dma_free_channel(ch);
+ goto out_fail;
+ }
+
+ tegra_apb_dma = ch;
+out:
+ mutex_unlock(&tegra_apb_dma_lock);
+ return true;
+
+out_fail:
+ mutex_unlock(&tegra_apb_dma_lock);
+ return false;
+}
+
+static void apb_dma_complete(struct tegra_dma_req *req)
+{
+ complete(&tegra_apb_wait);
+}
+
+u32 tegra_apb_readl(unsigned long offset)
+{
+ struct tegra_dma_req req;
+ int ret;
+
+ if (!tegra_apb_dma && !tegra_apb_init())
+ return readl(IO_TO_VIRT(offset));
+
+ mutex_lock(&tegra_apb_dma_lock);
+ req.complete = apb_dma_complete;
+ req.to_memory = 1;
+ req.dest_addr = tegra_apb_bb_phys;
+ req.dest_bus_width = 32;
+ req.dest_wrap = 1;
+ req.source_addr = offset;
+ req.source_bus_width = 32;
+ req.source_wrap = 4;
+ req.req_sel = TEGRA_DMA_REQ_SEL_CNTR;
+ req.size = 4;
+
+ INIT_COMPLETION(tegra_apb_wait);
+
+ tegra_dma_enqueue_req(tegra_apb_dma, &req);
+
+ ret = wait_for_completion_timeout(&tegra_apb_wait,
+ msecs_to_jiffies(50));
+
+ if (WARN(ret == 0, "apb read dma timed out")) {
+ tegra_dma_dequeue_req(tegra_apb_dma, &req);
+ *(u32 *)tegra_apb_bb = 0;
+ }
+
+ mutex_unlock(&tegra_apb_dma_lock);
+ return *((u32 *)tegra_apb_bb);
+}
+
+void tegra_apb_writel(u32 value, unsigned long offset)
+{
+ struct tegra_dma_req req;
+ int ret;
+
+ if (!tegra_apb_dma && !tegra_apb_init()) {
+ writel(value, IO_TO_VIRT(offset));
+ return;
+ }
+
+ mutex_lock(&tegra_apb_dma_lock);
+ *((u32 *)tegra_apb_bb) = value;
+ req.complete = apb_dma_complete;
+ req.to_memory = 0;
+ req.dest_addr = offset;
+ req.dest_wrap = 4;
+ req.dest_bus_width = 32;
+ req.source_addr = tegra_apb_bb_phys;
+ req.source_bus_width = 32;
+ req.source_wrap = 1;
+ req.req_sel = TEGRA_DMA_REQ_SEL_CNTR;
+ req.size = 4;
+
+ INIT_COMPLETION(tegra_apb_wait);
+
+ tegra_dma_enqueue_req(tegra_apb_dma, &req);
+
+ ret = wait_for_completion_timeout(&tegra_apb_wait,
+ msecs_to_jiffies(50));
+
+ if (WARN(ret == 0, "apb write dma timed out"))
+ tegra_dma_dequeue_req(tegra_apb_dma, &req);
+
+ mutex_unlock(&tegra_apb_dma_lock);
+}