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-rw-r--r--drivers/mfd/Kconfig6
-rw-r--r--drivers/mfd/Makefile1
-rw-r--r--drivers/mfd/vexpress-config.c277
-rw-r--r--drivers/mfd/vexpress-sysreg.c475
4 files changed, 759 insertions, 0 deletions
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 2c10938b3567..94bdf83b4bc8 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1080,3 +1080,9 @@ config MCP_UCB1200_TS
depends on MCP_UCB1200 && INPUT
endmenu
+
+config VEXPRESS_CONFIG
+ bool
+ help
+ Platform configuration infrastructure for the ARM Ltd.
+ Versatile Express.
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index b53db06d1b46..69f260ae0225 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -141,3 +141,4 @@ obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o
obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o
obj-$(CONFIG_MFD_SYSCON) += syscon.o
obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o
+obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o vexpress-sysreg.o
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);
diff --git a/drivers/mfd/vexpress-sysreg.c b/drivers/mfd/vexpress-sysreg.c
new file mode 100644
index 000000000000..733c06bd2d17
--- /dev/null
+++ b/drivers/mfd/vexpress-sysreg.c
@@ -0,0 +1,475 @@
+/*
+ * 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
+ */
+
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/leds.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/timer.h>
+#include <linux/vexpress.h>
+
+#define SYS_ID 0x000
+#define SYS_SW 0x004
+#define SYS_LED 0x008
+#define SYS_100HZ 0x024
+#define SYS_FLAGS 0x030
+#define SYS_FLAGSSET 0x030
+#define SYS_FLAGSCLR 0x034
+#define SYS_NVFLAGS 0x038
+#define SYS_NVFLAGSSET 0x038
+#define SYS_NVFLAGSCLR 0x03c
+#define SYS_MCI 0x048
+#define SYS_FLASH 0x04c
+#define SYS_CFGSW 0x058
+#define SYS_24MHZ 0x05c
+#define SYS_MISC 0x060
+#define SYS_DMA 0x064
+#define SYS_PROCID0 0x084
+#define SYS_PROCID1 0x088
+#define SYS_CFGDATA 0x0a0
+#define SYS_CFGCTRL 0x0a4
+#define SYS_CFGSTAT 0x0a8
+
+#define SYS_HBI_MASK 0xfff
+#define SYS_ID_HBI_SHIFT 16
+#define SYS_PROCIDx_HBI_SHIFT 0
+
+#define SYS_MCI_CARDIN (1 << 0)
+#define SYS_MCI_WPROT (1 << 1)
+
+#define SYS_FLASH_WPn (1 << 0)
+
+#define SYS_MISC_MASTERSITE (1 << 14)
+
+#define SYS_CFGCTRL_START (1 << 31)
+#define SYS_CFGCTRL_WRITE (1 << 30)
+#define SYS_CFGCTRL_DCC(n) (((n) & 0xf) << 26)
+#define SYS_CFGCTRL_FUNC(n) (((n) & 0x3f) << 20)
+#define SYS_CFGCTRL_SITE(n) (((n) & 0x3) << 16)
+#define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12)
+#define SYS_CFGCTRL_DEVICE(n) (((n) & 0xfff) << 0)
+
+#define SYS_CFGSTAT_ERR (1 << 1)
+#define SYS_CFGSTAT_COMPLETE (1 << 0)
+
+
+static void __iomem *vexpress_sysreg_base;
+static struct device *vexpress_sysreg_dev;
+static int vexpress_master_site;
+
+
+void vexpress_flags_set(u32 data)
+{
+ writel(~0, vexpress_sysreg_base + SYS_FLAGSCLR);
+ writel(data, vexpress_sysreg_base + SYS_FLAGSSET);
+}
+
+u32 vexpress_get_procid(int site)
+{
+ if (site == VEXPRESS_SITE_MASTER)
+ site = vexpress_master_site;
+
+ return readl(vexpress_sysreg_base + (site == VEXPRESS_SITE_DB1 ?
+ SYS_PROCID0 : SYS_PROCID1));
+}
+
+u32 vexpress_get_hbi(int site)
+{
+ u32 id;
+
+ switch (site) {
+ case VEXPRESS_SITE_MB:
+ id = readl(vexpress_sysreg_base + SYS_ID);
+ return (id >> SYS_ID_HBI_SHIFT) & SYS_HBI_MASK;
+ case VEXPRESS_SITE_MASTER:
+ case VEXPRESS_SITE_DB1:
+ case VEXPRESS_SITE_DB2:
+ id = vexpress_get_procid(site);
+ return (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
+ }
+
+ return ~0;
+}
+
+void __iomem *vexpress_get_24mhz_clock_base(void)
+{
+ return vexpress_sysreg_base + SYS_24MHZ;
+}
+
+
+static void vexpress_sysreg_find_prop(struct device_node *node,
+ const char *name, u32 *val)
+{
+ of_node_get(node);
+ while (node) {
+ if (of_property_read_u32(node, name, val) == 0) {
+ of_node_put(node);
+ return;
+ }
+ node = of_get_next_parent(node);
+ }
+}
+
+unsigned __vexpress_get_site(struct device *dev, struct device_node *node)
+{
+ u32 site = 0;
+
+ WARN_ON(dev && node && dev->of_node != node);
+ if (dev && !node)
+ node = dev->of_node;
+
+ if (node) {
+ vexpress_sysreg_find_prop(node, "arm,vexpress,site", &site);
+ } else if (dev && dev->bus == &platform_bus_type) {
+ struct platform_device *pdev = to_platform_device(dev);
+
+ if (pdev->num_resources == 1 &&
+ pdev->resource[0].flags == IORESOURCE_BUS)
+ site = pdev->resource[0].start;
+ } else if (dev && strncmp(dev_name(dev), "ct:", 3) == 0) {
+ site = VEXPRESS_SITE_MASTER;
+ }
+
+ if (site == VEXPRESS_SITE_MASTER)
+ site = vexpress_master_site;
+
+ return site;
+}
+
+
+struct vexpress_sysreg_config_func {
+ u32 template;
+ u32 device;
+};
+
+static struct vexpress_config_bridge *vexpress_sysreg_config_bridge;
+static struct timer_list vexpress_sysreg_config_timer;
+static u32 *vexpress_sysreg_config_data;
+static int vexpress_sysreg_config_tries;
+
+static void *vexpress_sysreg_config_func_get(struct device *dev,
+ struct device_node *node)
+{
+ struct vexpress_sysreg_config_func *config_func;
+ u32 site;
+ u32 position = 0;
+ u32 dcc = 0;
+ u32 func_device[2];
+ int err = -EFAULT;
+
+ if (node) {
+ of_node_get(node);
+ vexpress_sysreg_find_prop(node, "arm,vexpress,site", &site);
+ vexpress_sysreg_find_prop(node, "arm,vexpress,position",
+ &position);
+ vexpress_sysreg_find_prop(node, "arm,vexpress,dcc", &dcc);
+ err = of_property_read_u32_array(node,
+ "arm,vexpress-sysreg,func", func_device,
+ ARRAY_SIZE(func_device));
+ of_node_put(node);
+ } else if (dev && dev->bus == &platform_bus_type) {
+ struct platform_device *pdev = to_platform_device(dev);
+
+ if (pdev->num_resources == 1 &&
+ pdev->resource[0].flags == IORESOURCE_BUS) {
+ site = pdev->resource[0].start;
+ func_device[0] = pdev->resource[0].end;
+ func_device[1] = pdev->id;
+ err = 0;
+ }
+ }
+ if (err)
+ return NULL;
+
+ config_func = kzalloc(sizeof(*config_func), GFP_KERNEL);
+ if (!config_func)
+ return NULL;
+
+ config_func->template = SYS_CFGCTRL_DCC(dcc);
+ config_func->template |= SYS_CFGCTRL_FUNC(func_device[0]);
+ config_func->template |= SYS_CFGCTRL_SITE(site == VEXPRESS_SITE_MASTER ?
+ vexpress_master_site : site);
+ config_func->template |= SYS_CFGCTRL_POSITION(position);
+ config_func->device |= func_device[1];
+
+ dev_dbg(vexpress_sysreg_dev, "func 0x%p = 0x%x, %d\n", config_func,
+ config_func->template, config_func->device);
+
+ return config_func;
+}
+
+static void vexpress_sysreg_config_func_put(void *func)
+{
+ kfree(func);
+}
+
+static int vexpress_sysreg_config_func_exec(void *func, int offset,
+ bool write, u32 *data)
+{
+ int status;
+ struct vexpress_sysreg_config_func *config_func = func;
+ u32 command;
+
+ if (WARN_ON(!vexpress_sysreg_base))
+ return -ENOENT;
+
+ command = readl(vexpress_sysreg_base + SYS_CFGCTRL);
+ if (WARN_ON(command & SYS_CFGCTRL_START))
+ return -EBUSY;
+
+ command = SYS_CFGCTRL_START;
+ command |= write ? SYS_CFGCTRL_WRITE : 0;
+ command |= config_func->template;
+ command |= SYS_CFGCTRL_DEVICE(config_func->device + offset);
+
+ /* Use a canary for reads */
+ if (!write)
+ *data = 0xdeadbeef;
+
+ dev_dbg(vexpress_sysreg_dev, "command %x, data %x\n",
+ command, *data);
+ writel(*data, vexpress_sysreg_base + SYS_CFGDATA);
+ writel(0, vexpress_sysreg_base + SYS_CFGSTAT);
+ writel(command, vexpress_sysreg_base + SYS_CFGCTRL);
+ mb();
+
+ if (vexpress_sysreg_dev) {
+ /* Schedule completion check */
+ if (!write)
+ vexpress_sysreg_config_data = data;
+ vexpress_sysreg_config_tries = 100;
+ mod_timer(&vexpress_sysreg_config_timer,
+ jiffies + usecs_to_jiffies(100));
+ status = VEXPRESS_CONFIG_STATUS_WAIT;
+ } else {
+ /* Early execution, no timer available, have to spin */
+ u32 cfgstat;
+
+ do {
+ cpu_relax();
+ cfgstat = readl(vexpress_sysreg_base + SYS_CFGSTAT);
+ } while (!cfgstat);
+
+ if (!write && (cfgstat & SYS_CFGSTAT_COMPLETE))
+ *data = readl(vexpress_sysreg_base + SYS_CFGDATA);
+ status = VEXPRESS_CONFIG_STATUS_DONE;
+
+ if (cfgstat & SYS_CFGSTAT_ERR)
+ status = -EINVAL;
+ }
+
+ return status;
+}
+
+struct vexpress_config_bridge_info vexpress_sysreg_config_bridge_info = {
+ .name = "vexpress-sysreg",
+ .func_get = vexpress_sysreg_config_func_get,
+ .func_put = vexpress_sysreg_config_func_put,
+ .func_exec = vexpress_sysreg_config_func_exec,
+};
+
+static void vexpress_sysreg_config_complete(unsigned long data)
+{
+ int status = VEXPRESS_CONFIG_STATUS_DONE;
+ u32 cfgstat = readl(vexpress_sysreg_base + SYS_CFGSTAT);
+
+ if (cfgstat & SYS_CFGSTAT_ERR)
+ status = -EINVAL;
+ if (!vexpress_sysreg_config_tries--)
+ status = -ETIMEDOUT;
+
+ if (status < 0) {
+ dev_err(vexpress_sysreg_dev, "error %d\n", status);
+ } else if (!(cfgstat & SYS_CFGSTAT_COMPLETE)) {
+ mod_timer(&vexpress_sysreg_config_timer,
+ jiffies + usecs_to_jiffies(50));
+ return;
+ }
+
+ if (vexpress_sysreg_config_data) {
+ *vexpress_sysreg_config_data = readl(vexpress_sysreg_base +
+ SYS_CFGDATA);
+ dev_dbg(vexpress_sysreg_dev, "read data %x\n",
+ *vexpress_sysreg_config_data);
+ vexpress_sysreg_config_data = NULL;
+ }
+
+ vexpress_config_complete(vexpress_sysreg_config_bridge, status);
+}
+
+
+void __init vexpress_sysreg_early_init(void __iomem *base)
+{
+ struct device_node *node = of_find_compatible_node(NULL, NULL,
+ "arm,vexpress-sysreg");
+
+ if (node)
+ base = of_iomap(node, 0);
+
+ if (WARN_ON(!base))
+ return;
+
+ vexpress_sysreg_base = base;
+
+ if (readl(vexpress_sysreg_base + SYS_MISC) & SYS_MISC_MASTERSITE)
+ vexpress_master_site = VEXPRESS_SITE_DB2;
+ else
+ vexpress_master_site = VEXPRESS_SITE_DB1;
+
+ vexpress_sysreg_config_bridge = vexpress_config_bridge_register(
+ node, &vexpress_sysreg_config_bridge_info);
+ WARN_ON(!vexpress_sysreg_config_bridge);
+}
+
+void __init vexpress_sysreg_of_early_init(void)
+{
+ vexpress_sysreg_early_init(NULL);
+}
+
+
+static struct vexpress_sysreg_gpio {
+ unsigned long reg;
+ u32 value;
+} vexpress_sysreg_gpios[] = {
+ [VEXPRESS_GPIO_MMC_CARDIN] = {
+ .reg = SYS_MCI,
+ .value = SYS_MCI_CARDIN,
+ },
+ [VEXPRESS_GPIO_MMC_WPROT] = {
+ .reg = SYS_MCI,
+ .value = SYS_MCI_WPROT,
+ },
+ [VEXPRESS_GPIO_FLASH_WPn] = {
+ .reg = SYS_FLASH,
+ .value = SYS_FLASH_WPn,
+ },
+};
+
+static int vexpress_sysreg_gpio_direction_input(struct gpio_chip *chip,
+ unsigned offset)
+{
+ return 0;
+}
+
+static int vexpress_sysreg_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ return 0;
+}
+
+static int vexpress_sysreg_gpio_get(struct gpio_chip *chip,
+ unsigned offset)
+{
+ struct vexpress_sysreg_gpio *gpio = &vexpress_sysreg_gpios[offset];
+ u32 reg_value = readl(vexpress_sysreg_base + gpio->reg);
+
+ return !!(reg_value & gpio->value);
+}
+
+static void vexpress_sysreg_gpio_set(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ struct vexpress_sysreg_gpio *gpio = &vexpress_sysreg_gpios[offset];
+ u32 reg_value = readl(vexpress_sysreg_base + gpio->reg);
+
+ if (value)
+ reg_value |= gpio->value;
+ else
+ reg_value &= ~gpio->value;
+
+ writel(reg_value, vexpress_sysreg_base + gpio->reg);
+}
+
+static struct gpio_chip vexpress_sysreg_gpio_chip = {
+ .label = "vexpress-sysreg",
+ .direction_input = vexpress_sysreg_gpio_direction_input,
+ .direction_output = vexpress_sysreg_gpio_direction_output,
+ .get = vexpress_sysreg_gpio_get,
+ .set = vexpress_sysreg_gpio_set,
+ .ngpio = ARRAY_SIZE(vexpress_sysreg_gpios),
+ .base = 0,
+};
+
+
+static ssize_t vexpress_sysreg_sys_id_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", readl(vexpress_sysreg_base + SYS_ID));
+}
+
+DEVICE_ATTR(sys_id, S_IRUGO, vexpress_sysreg_sys_id_show, NULL);
+
+static int __devinit vexpress_sysreg_probe(struct platform_device *pdev)
+{
+ int err;
+ struct resource *res = platform_get_resource(pdev,
+ IORESOURCE_MEM, 0);
+
+ if (!devm_request_mem_region(&pdev->dev, res->start,
+ resource_size(res), pdev->name)) {
+ dev_err(&pdev->dev, "Failed to request memory region!\n");
+ return -EBUSY;
+ }
+
+ if (!vexpress_sysreg_base)
+ vexpress_sysreg_base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+
+ if (!vexpress_sysreg_base) {
+ dev_err(&pdev->dev, "Failed to obtain base address!\n");
+ return -EFAULT;
+ }
+
+ setup_timer(&vexpress_sysreg_config_timer,
+ vexpress_sysreg_config_complete, 0);
+
+ vexpress_sysreg_gpio_chip.dev = &pdev->dev;
+ err = gpiochip_add(&vexpress_sysreg_gpio_chip);
+ if (err) {
+ vexpress_config_bridge_unregister(
+ vexpress_sysreg_config_bridge);
+ dev_err(&pdev->dev, "Failed to register GPIO chip! (%d)\n",
+ err);
+ return err;
+ }
+
+ vexpress_sysreg_dev = &pdev->dev;
+
+ device_create_file(vexpress_sysreg_dev, &dev_attr_sys_id);
+
+ return 0;
+}
+
+static const struct of_device_id vexpress_sysreg_match[] = {
+ { .compatible = "arm,vexpress-sysreg", },
+ {},
+};
+
+static struct platform_driver vexpress_sysreg_driver = {
+ .driver = {
+ .name = "vexpress-sysreg",
+ .of_match_table = vexpress_sysreg_match,
+ },
+ .probe = vexpress_sysreg_probe,
+};
+
+static int __init vexpress_sysreg_init(void)
+{
+ return platform_driver_register(&vexpress_sysreg_driver);
+}
+core_initcall(vexpress_sysreg_init);