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-rw-r--r--kernel/drivers/of/device.c276
1 files changed, 276 insertions, 0 deletions
diff --git a/kernel/drivers/of/device.c b/kernel/drivers/of/device.c
new file mode 100644
index 000000000..20c1332a0
--- /dev/null
+++ b/kernel/drivers/of/device.c
@@ -0,0 +1,276 @@
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/of_iommu.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/slab.h>
+
+#include <asm/errno.h>
+#include "of_private.h"
+
+/**
+ * of_match_device - Tell if a struct device matches an of_device_id list
+ * @ids: array of of device match structures to search in
+ * @dev: the of device structure to match against
+ *
+ * Used by a driver to check whether an platform_device present in the
+ * system is in its list of supported devices.
+ */
+const struct of_device_id *of_match_device(const struct of_device_id *matches,
+ const struct device *dev)
+{
+ if ((!matches) || (!dev->of_node))
+ return NULL;
+ return of_match_node(matches, dev->of_node);
+}
+EXPORT_SYMBOL(of_match_device);
+
+struct platform_device *of_dev_get(struct platform_device *dev)
+{
+ struct device *tmp;
+
+ if (!dev)
+ return NULL;
+ tmp = get_device(&dev->dev);
+ if (tmp)
+ return to_platform_device(tmp);
+ else
+ return NULL;
+}
+EXPORT_SYMBOL(of_dev_get);
+
+void of_dev_put(struct platform_device *dev)
+{
+ if (dev)
+ put_device(&dev->dev);
+}
+EXPORT_SYMBOL(of_dev_put);
+
+int of_device_add(struct platform_device *ofdev)
+{
+ BUG_ON(ofdev->dev.of_node == NULL);
+
+ /* name and id have to be set so that the platform bus doesn't get
+ * confused on matching */
+ ofdev->name = dev_name(&ofdev->dev);
+ ofdev->id = -1;
+
+ /* device_add will assume that this device is on the same node as
+ * the parent. If there is no parent defined, set the node
+ * explicitly */
+ if (!ofdev->dev.parent)
+ set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
+
+ return device_add(&ofdev->dev);
+}
+
+/**
+ * of_dma_configure - Setup DMA configuration
+ * @dev: Device to apply DMA configuration
+ * @np: Pointer to OF node having DMA configuration
+ *
+ * Try to get devices's DMA configuration from DT and update it
+ * accordingly.
+ *
+ * If platform code needs to use its own special DMA configuration, it
+ * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
+ * to fix up DMA configuration.
+ */
+void of_dma_configure(struct device *dev, struct device_node *np)
+{
+ u64 dma_addr, paddr, size;
+ int ret;
+ bool coherent;
+ unsigned long offset;
+ struct iommu_ops *iommu;
+
+ /*
+ * Set default coherent_dma_mask to 32 bit. Drivers are expected to
+ * setup the correct supported mask.
+ */
+ if (!dev->coherent_dma_mask)
+ dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+ /*
+ * Set it to coherent_dma_mask by default if the architecture
+ * code has not set it.
+ */
+ if (!dev->dma_mask)
+ dev->dma_mask = &dev->coherent_dma_mask;
+
+ ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
+ if (ret < 0) {
+ dma_addr = offset = 0;
+ size = dev->coherent_dma_mask + 1;
+ } else {
+ offset = PFN_DOWN(paddr - dma_addr);
+
+ /*
+ * Add a work around to treat the size as mask + 1 in case
+ * it is defined in DT as a mask.
+ */
+ if (size & 1) {
+ dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
+ size);
+ size = size + 1;
+ }
+
+ if (!size) {
+ dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
+ return;
+ }
+ dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
+ }
+
+ dev->dma_pfn_offset = offset;
+
+ /*
+ * Limit coherent and dma mask based on size and default mask
+ * set by the driver.
+ */
+ dev->coherent_dma_mask = min(dev->coherent_dma_mask,
+ DMA_BIT_MASK(ilog2(dma_addr + size)));
+ *dev->dma_mask = min((*dev->dma_mask),
+ DMA_BIT_MASK(ilog2(dma_addr + size)));
+
+ coherent = of_dma_is_coherent(np);
+ dev_dbg(dev, "device is%sdma coherent\n",
+ coherent ? " " : " not ");
+
+ iommu = of_iommu_configure(dev, np);
+ dev_dbg(dev, "device is%sbehind an iommu\n",
+ iommu ? " " : " not ");
+
+ arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
+}
+EXPORT_SYMBOL_GPL(of_dma_configure);
+
+int of_device_register(struct platform_device *pdev)
+{
+ device_initialize(&pdev->dev);
+ return of_device_add(pdev);
+}
+EXPORT_SYMBOL(of_device_register);
+
+void of_device_unregister(struct platform_device *ofdev)
+{
+ device_unregister(&ofdev->dev);
+}
+EXPORT_SYMBOL(of_device_unregister);
+
+ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
+{
+ const char *compat;
+ int cplen, i;
+ ssize_t tsize, csize, repend;
+
+ if ((!dev) || (!dev->of_node))
+ return -ENODEV;
+
+ /* Name & Type */
+ csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
+ dev->of_node->type);
+
+ /* Get compatible property if any */
+ compat = of_get_property(dev->of_node, "compatible", &cplen);
+ if (!compat)
+ return csize;
+
+ /* Find true end (we tolerate multiple \0 at the end */
+ for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
+ cplen--;
+ if (!cplen)
+ return csize;
+ cplen++;
+
+ /* Check space (need cplen+1 chars including final \0) */
+ tsize = csize + cplen;
+ repend = tsize;
+
+ if (csize >= len) /* @ the limit, all is already filled */
+ return tsize;
+
+ if (tsize >= len) { /* limit compat list */
+ cplen = len - csize - 1;
+ repend = len;
+ }
+
+ /* Copy and do char replacement */
+ memcpy(&str[csize + 1], compat, cplen);
+ for (i = csize; i < repend; i++) {
+ char c = str[i];
+ if (c == '\0')
+ str[i] = 'C';
+ else if (c == ' ')
+ str[i] = '_';
+ }
+
+ return tsize;
+}
+
+/**
+ * of_device_uevent - Display OF related uevent information
+ */
+void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ const char *compat;
+ struct alias_prop *app;
+ int seen = 0, cplen, sl;
+
+ if ((!dev) || (!dev->of_node))
+ return;
+
+ add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
+ add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
+ if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
+ add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);
+
+ /* Since the compatible field can contain pretty much anything
+ * it's not really legal to split it out with commas. We split it
+ * up using a number of environment variables instead. */
+ compat = of_get_property(dev->of_node, "compatible", &cplen);
+ while (compat && *compat && cplen > 0) {
+ add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
+ sl = strlen(compat) + 1;
+ compat += sl;
+ cplen -= sl;
+ seen++;
+ }
+ add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
+
+ seen = 0;
+ mutex_lock(&of_mutex);
+ list_for_each_entry(app, &aliases_lookup, link) {
+ if (dev->of_node == app->np) {
+ add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
+ app->alias);
+ seen++;
+ }
+ }
+ mutex_unlock(&of_mutex);
+}
+
+int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
+{
+ int sl;
+
+ if ((!dev) || (!dev->of_node))
+ return -ENODEV;
+
+ /* Devicetree modalias is tricky, we add it in 2 steps */
+ if (add_uevent_var(env, "MODALIAS="))
+ return -ENOMEM;
+
+ sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
+ sizeof(env->buf) - env->buflen);
+ if (sl >= (sizeof(env->buf) - env->buflen))
+ return -ENOMEM;
+ env->buflen += sl;
+
+ return 0;
+}