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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-13 00:05:15 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-13 00:05:15 +0400
commitd027db132b395dabfac208e52a7e510e441bb9d2 (patch)
tree24b055b2385f9848e77e646ce475991d8675c3c4 /drivers/mfd/vexpress-config.c
parentd01e4afdbb65e030fd6f1f96c30a558e2eb0f279 (diff)
parent5faf7cbb848da827f6ea1458b5a1c26a44e7510a (diff)
downloadlinux-d027db132b395dabfac208e52a7e510e441bb9d2.tar.xz
Merge tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC updates from Olof Johansson: "This contains the bulk of new SoC development for this merge window. Two new platforms have been added, the sunxi platforms (Allwinner A1x SoCs) by Maxime Ripard, and a generic Broadcom platform for a new series of ARMv7 platforms from them, where the hope is that we can keep the platform code generic enough to have them all share one mach directory. The new Broadcom platform is contributed by Christian Daudt. Highbank has grown support for Calxeda's next generation of hardware, ECX-2000. clps711x has seen a lot of cleanup from Alexander Shiyan, and he's also taken on maintainership of the platform. Beyond this there has been a bunch of work from a number of people on converting more platforms to IRQ domains, pinctrl conversion, cleanup and general feature enablement across most of the active platforms." Fix up trivial conflicts as per Olof. * tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (174 commits) mfd: vexpress-sysreg: Remove LEDs code irqchip: irq-sunxi: Add terminating entry for sunxi_irq_dt_ids clocksource: sunxi_timer: Add terminating entry for sunxi_timer_dt_ids irq: versatile: delete dangling variable ARM: sunxi: add missing include for mdelay() ARM: EXYNOS: Avoid early use of of_machine_is_compatible() ARM: dts: add node for PL330 MDMA1 controller for exynos4 ARM: EXYNOS: Add support for secondary CPU bring-up on Exynos4412 ARM: EXYNOS: add UART3 to DEBUG_LL ports ARM: S3C24XX: Add clkdev entry for camif-upll clock ARM: SAMSUNG: Add s3c24xx/s3c64xx CAMIF GPIO setup helpers ARM: sunxi: Add missing sun4i.dtsi file pinctrl: samsung: Do not initialise statics to 0 ARM i.MX6: remove gate_mask from pllv3 ARM i.MX6: Fix ethernet PLL clocks ARM i.MX6: rename PLLs according to datasheet ARM i.MX6: Add pwm support ARM i.MX51: Add pwm support ARM i.MX53: Add pwm support ARM: mx5: Replace clk_register_clkdev with clock DT lookup ...
Diffstat (limited to 'drivers/mfd/vexpress-config.c')
-rw-r--r--drivers/mfd/vexpress-config.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/mfd/vexpress-config.c b/drivers/mfd/vexpress-config.c
new file mode 100644
index 000000000000..fae15d880758
--- /dev/null
+++ b/drivers/mfd/vexpress-config.c
@@ -0,0 +1,277 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#define pr_fmt(fmt) "vexpress-config: " fmt
+
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/vexpress.h>
+
+
+#define VEXPRESS_CONFIG_MAX_BRIDGES 2
+
+struct vexpress_config_bridge {
+ struct device_node *node;
+ struct vexpress_config_bridge_info *info;
+ struct list_head transactions;
+ spinlock_t transactions_lock;
+} vexpress_config_bridges[VEXPRESS_CONFIG_MAX_BRIDGES];
+
+static DECLARE_BITMAP(vexpress_config_bridges_map,
+ ARRAY_SIZE(vexpress_config_bridges));
+static DEFINE_MUTEX(vexpress_config_bridges_mutex);
+
+struct vexpress_config_bridge *vexpress_config_bridge_register(
+ struct device_node *node,
+ struct vexpress_config_bridge_info *info)
+{
+ struct vexpress_config_bridge *bridge;
+ int i;
+
+ pr_debug("Registering bridge '%s'\n", info->name);
+
+ mutex_lock(&vexpress_config_bridges_mutex);
+ i = find_first_zero_bit(vexpress_config_bridges_map,
+ ARRAY_SIZE(vexpress_config_bridges));
+ if (i >= ARRAY_SIZE(vexpress_config_bridges)) {
+ pr_err("Can't register more bridges!\n");
+ mutex_unlock(&vexpress_config_bridges_mutex);
+ return NULL;
+ }
+ __set_bit(i, vexpress_config_bridges_map);
+ bridge = &vexpress_config_bridges[i];
+
+ bridge->node = node;
+ bridge->info = info;
+ INIT_LIST_HEAD(&bridge->transactions);
+ spin_lock_init(&bridge->transactions_lock);
+
+ mutex_unlock(&vexpress_config_bridges_mutex);
+
+ return bridge;
+}
+
+void vexpress_config_bridge_unregister(struct vexpress_config_bridge *bridge)
+{
+ struct vexpress_config_bridge __bridge = *bridge;
+ int i;
+
+ mutex_lock(&vexpress_config_bridges_mutex);
+ for (i = 0; i < ARRAY_SIZE(vexpress_config_bridges); i++)
+ if (&vexpress_config_bridges[i] == bridge)
+ __clear_bit(i, vexpress_config_bridges_map);
+ mutex_unlock(&vexpress_config_bridges_mutex);
+
+ WARN_ON(!list_empty(&__bridge.transactions));
+ while (!list_empty(&__bridge.transactions))
+ cpu_relax();
+}
+
+
+struct vexpress_config_func {
+ struct vexpress_config_bridge *bridge;
+ void *func;
+};
+
+struct vexpress_config_func *__vexpress_config_func_get(struct device *dev,
+ struct device_node *node)
+{
+ struct device_node *bridge_node;
+ struct vexpress_config_func *func;
+ int i;
+
+ if (WARN_ON(dev && node && dev->of_node != node))
+ return NULL;
+ if (dev && !node)
+ node = dev->of_node;
+
+ func = kzalloc(sizeof(*func), GFP_KERNEL);
+ if (!func)
+ return NULL;
+
+ bridge_node = of_node_get(node);
+ while (bridge_node) {
+ const __be32 *prop = of_get_property(bridge_node,
+ "arm,vexpress,config-bridge", NULL);
+
+ if (prop) {
+ bridge_node = of_find_node_by_phandle(
+ be32_to_cpup(prop));
+ break;
+ }
+
+ bridge_node = of_get_next_parent(bridge_node);
+ }
+
+ mutex_lock(&vexpress_config_bridges_mutex);
+ for (i = 0; i < ARRAY_SIZE(vexpress_config_bridges); i++) {
+ struct vexpress_config_bridge *bridge =
+ &vexpress_config_bridges[i];
+
+ if (test_bit(i, vexpress_config_bridges_map) &&
+ bridge->node == bridge_node) {
+ func->bridge = bridge;
+ func->func = bridge->info->func_get(dev, node);
+ break;
+ }
+ }
+ mutex_unlock(&vexpress_config_bridges_mutex);
+
+ if (!func->func) {
+ of_node_put(node);
+ kfree(func);
+ return NULL;
+ }
+
+ return func;
+}
+
+void vexpress_config_func_put(struct vexpress_config_func *func)
+{
+ func->bridge->info->func_put(func->func);
+ of_node_put(func->bridge->node);
+ kfree(func);
+}
+
+
+struct vexpress_config_trans {
+ struct vexpress_config_func *func;
+ int offset;
+ bool write;
+ u32 *data;
+ int status;
+ struct completion completion;
+ struct list_head list;
+};
+
+static void vexpress_config_dump_trans(const char *what,
+ struct vexpress_config_trans *trans)
+{
+ pr_debug("%s %s trans %p func 0x%p offset %d data 0x%x status %d\n",
+ what, trans->write ? "write" : "read", trans,
+ trans->func->func, trans->offset,
+ trans->data ? *trans->data : 0, trans->status);
+}
+
+static int vexpress_config_schedule(struct vexpress_config_trans *trans)
+{
+ int status;
+ struct vexpress_config_bridge *bridge = trans->func->bridge;
+ unsigned long flags;
+
+ init_completion(&trans->completion);
+ trans->status = -EFAULT;
+
+ spin_lock_irqsave(&bridge->transactions_lock, flags);
+
+ vexpress_config_dump_trans("Executing", trans);
+
+ if (list_empty(&bridge->transactions))
+ status = bridge->info->func_exec(trans->func->func,
+ trans->offset, trans->write, trans->data);
+ else
+ status = VEXPRESS_CONFIG_STATUS_WAIT;
+
+ switch (status) {
+ case VEXPRESS_CONFIG_STATUS_DONE:
+ vexpress_config_dump_trans("Finished", trans);
+ trans->status = status;
+ break;
+ case VEXPRESS_CONFIG_STATUS_WAIT:
+ list_add_tail(&trans->list, &bridge->transactions);
+ break;
+ }
+
+ spin_unlock_irqrestore(&bridge->transactions_lock, flags);
+
+ return status;
+}
+
+void vexpress_config_complete(struct vexpress_config_bridge *bridge,
+ int status)
+{
+ struct vexpress_config_trans *trans;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bridge->transactions_lock, flags);
+
+ trans = list_first_entry(&bridge->transactions,
+ struct vexpress_config_trans, list);
+ vexpress_config_dump_trans("Completed", trans);
+
+ trans->status = status;
+ list_del(&trans->list);
+
+ if (!list_empty(&bridge->transactions)) {
+ vexpress_config_dump_trans("Pending", trans);
+
+ bridge->info->func_exec(trans->func->func, trans->offset,
+ trans->write, trans->data);
+ }
+ spin_unlock_irqrestore(&bridge->transactions_lock, flags);
+
+ complete(&trans->completion);
+}
+
+int vexpress_config_wait(struct vexpress_config_trans *trans)
+{
+ wait_for_completion(&trans->completion);
+
+ return trans->status;
+}
+
+
+int vexpress_config_read(struct vexpress_config_func *func, int offset,
+ u32 *data)
+{
+ struct vexpress_config_trans trans = {
+ .func = func,
+ .offset = offset,
+ .write = false,
+ .data = data,
+ .status = 0,
+ };
+ int status = vexpress_config_schedule(&trans);
+
+ if (status == VEXPRESS_CONFIG_STATUS_WAIT)
+ status = vexpress_config_wait(&trans);
+
+ return status;
+}
+EXPORT_SYMBOL(vexpress_config_read);
+
+int vexpress_config_write(struct vexpress_config_func *func, int offset,
+ u32 data)
+{
+ struct vexpress_config_trans trans = {
+ .func = func,
+ .offset = offset,
+ .write = true,
+ .data = &data,
+ .status = 0,
+ };
+ int status = vexpress_config_schedule(&trans);
+
+ if (status == VEXPRESS_CONFIG_STATUS_WAIT)
+ status = vexpress_config_wait(&trans);
+
+ return status;
+}
+EXPORT_SYMBOL(vexpress_config_write);