drm: simplify sysfs code for drm

This simplifies the sysfs code for the drm and add a dri_library_name
attribute which can be used by a userspace app to figure out which
library to load.

From: Jon Smirl <jonsmirl@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/char/drm/drmP.h

@@ -547,6 +547,7 @@ struct drm_driver {
 	void (*kernel_context_switch_unlock) (struct drm_device * dev,
 					      drm_lock_t * lock);
 	int (*vblank_wait) (struct drm_device * dev, unsigned int *sequence);
+	int (*dri_library_name) (struct drm_device *dev, char *buf);
 
 	/**
 	 * Called by \c drm_device_is_agp.  Typically used to determine if a
@@ -982,10 +983,8 @@ extern struct drm_sysfs_class *drm_sysfs_create(struct module *owner,
 						char *name);
 extern void drm_sysfs_destroy(struct drm_sysfs_class *cs);
 extern struct class_device *drm_sysfs_device_add(struct drm_sysfs_class *cs,
-						 dev_t dev,
-						 struct device *device,
-						 const char *fmt, ...);
-extern void drm_sysfs_device_remove(dev_t dev);
+						 drm_head_t *head);
+extern void drm_sysfs_device_remove(struct class_device *class_dev);
 
 /* Inline replacements for DRM_IOREMAP macros */
 static __inline__ void drm_core_ioremap(struct drm_map *map,

drivers/char/drm/drm_stub.c

@@ -200,11 +200,7 @@ static int drm_get_head(drm_device_t * dev, drm_head_t * head)
 				goto err_g1;
 			}
 
-			head->dev_class = drm_sysfs_device_add(drm_class,
-							       MKDEV(DRM_MAJOR,
-								     minor),
-							       &dev->pdev->dev,
-							       "card%d", minor);
+			head->dev_class = drm_sysfs_device_add(drm_class, head);
 			if (IS_ERR(head->dev_class)) {
 				printk(KERN_ERR
 				       "DRM: Error sysfs_device_add.\n");
@@ -317,10 +313,9 @@ int drm_put_head(drm_head_t * head)
 	DRM_DEBUG("release secondary minor %d\n", minor);
 
 	drm_proc_cleanup(minor, drm_proc_root, head->dev_root);
-	drm_sysfs_device_remove(MKDEV(DRM_MAJOR, head->minor));
+	drm_sysfs_device_remove(head->dev_class);
 
-	*head = (drm_head_t) {
-	.dev = NULL};
+	*head = (drm_head_t) {.dev = NULL};
 
 	drm_heads[minor] = NULL;
 

drivers/char/drm/drm_sysfs.c

@@ -15,8 +15,6 @@
 #include <linux/device.h>
 #include <linux/kdev_t.h>
 #include <linux/err.h>
-#include <linux/slab.h>
-#include <linux/string.h>
 
 #include "drm_core.h"
 #include "drmP.h"
@@ -28,15 +26,11 @@ struct drm_sysfs_class {
 #define to_drm_sysfs_class(d) container_of(d, struct drm_sysfs_class, class)
 
 struct simple_dev {
-	struct list_head node;
 	dev_t dev;
 	struct class_device class_dev;
 };
 #define to_simple_dev(d) container_of(d, struct simple_dev, class_dev)
 
-static LIST_HEAD(simple_dev_list);
-static DEFINE_SPINLOCK(simple_dev_list_lock);
-
 static void release_simple_dev(struct class_device *class_dev)
 {
 	struct simple_dev *s_dev = to_simple_dev(class_dev);
@@ -124,6 +118,18 @@ void drm_sysfs_destroy(struct drm_sysfs_class *cs)
 	class_unregister(&cs->class);
 }
 
+static ssize_t show_dri(struct class_device *class_device, char *buf)
+{
+	drm_device_t * dev = ((drm_head_t *)class_get_devdata(class_device))->dev;
+	if (dev->driver->dri_library_name)
+		return dev->driver->dri_library_name(dev, buf);
+	return snprintf(buf, PAGE_SIZE, "%s\n", dev->driver->pci_driver.name);
+}
+
+static struct class_device_attribute class_device_attrs[] = {
+	__ATTR(dri_library_name, S_IRUGO, show_dri, NULL),
+};
+
 /**
  * drm_sysfs_device_add - adds a class device to sysfs for a character driver
  * @cs: pointer to the struct drm_sysfs_class that this device should be registered to.
@@ -138,13 +144,11 @@ void drm_sysfs_destroy(struct drm_sysfs_class *cs)
  * Note: the struct drm_sysfs_class passed to this function must have previously been
  * created with a call to drm_sysfs_create().
  */
-struct class_device *drm_sysfs_device_add(struct drm_sysfs_class *cs, dev_t dev,
-					  struct device *device,
-					  const char *fmt, ...)
+struct class_device *drm_sysfs_device_add(struct drm_sysfs_class *cs,
+					  drm_head_t *head)
 {
-	va_list args;
 	struct simple_dev *s_dev = NULL;
-	int retval;
+	int i, retval;
 
 	if ((cs == NULL) || (IS_ERR(cs))) {
 		retval = -ENODEV;
@@ -158,26 +162,23 @@ struct class_device *drm_sysfs_device_add(struct drm_sysfs_class *cs, dev_t dev,
 	}
 	memset(s_dev, 0x00, sizeof(*s_dev));
 
-	s_dev->dev = dev;
-	s_dev->class_dev.dev = device;
+	s_dev->dev = MKDEV(DRM_MAJOR, head->minor);
+	s_dev->class_dev.dev = &(head->dev->pdev)->dev;
 	s_dev->class_dev.class = &cs->class;
 
-	va_start(args, fmt);
-	vsnprintf(s_dev->class_dev.class_id, BUS_ID_SIZE, fmt, args);
-	va_end(args);
+	snprintf(s_dev->class_dev.class_id, BUS_ID_SIZE, "card%d", head->minor);
 	retval = class_device_register(&s_dev->class_dev);
 	if (retval)
 		goto error;
 
 	class_device_create_file(&s_dev->class_dev, &cs->attr);
+	class_set_devdata(&s_dev->class_dev, head);
 
-	spin_lock(&simple_dev_list_lock);
-	list_add(&s_dev->node, &simple_dev_list);
-	spin_unlock(&simple_dev_list_lock);
-
+	for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++)
+		class_device_create_file(&s_dev->class_dev, &class_device_attrs[i]);
 	return &s_dev->class_dev;
 
-      error:
+error:
 	kfree(s_dev);
 	return ERR_PTR(retval);
 }
@@ -189,23 +190,12 @@ struct class_device *drm_sysfs_device_add(struct drm_sysfs_class *cs, dev_t dev,
  * This call unregisters and cleans up a class device that was created with a
  * call to drm_sysfs_device_add()
  */
-void drm_sysfs_device_remove(dev_t dev)
+void drm_sysfs_device_remove(struct class_device *class_dev)
 {
-	struct simple_dev *s_dev = NULL;
-	int found = 0;
-
-	spin_lock(&simple_dev_list_lock);
-	list_for_each_entry(s_dev, &simple_dev_list, node) {
-		if (s_dev->dev == dev) {
-			found = 1;
-			break;
-		}
-	}
-	if (found) {
-		list_del(&s_dev->node);
-		spin_unlock(&simple_dev_list_lock);
-		class_device_unregister(&s_dev->class_dev);
-	} else {
-		spin_unlock(&simple_dev_list_lock);
-	}
+	struct simple_dev *s_dev = to_simple_dev(class_dev);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++)
+		class_device_remove_file(&s_dev->class_dev, &class_device_attrs[i]);
+	class_device_unregister(&s_dev->class_dev);
 }

drivers/char/drm/radeon_drv.c

@@ -42,6 +42,16 @@ int radeon_no_wb;
 MODULE_PARM_DESC(no_wb, "Disable AGP writeback for scratch registers\n");
 module_param_named(no_wb, radeon_no_wb, int, 0444);
 
+static int dri_library_name(struct drm_device *dev, char *buf)
+{
+	drm_radeon_private_t *dev_priv = dev->dev_private;
+	int family = dev_priv->flags & CHIP_FAMILY_MASK;
+
+	return snprintf(buf, PAGE_SIZE, "%s\n",
+		        (family < CHIP_R200) ? "radeon" :
+		        ((family < CHIP_R300) ? "r200" :
+		        "r300"));
+}
 
 static struct pci_device_id pciidlist[] = {
 	radeon_PCI_IDS
@@ -61,6 +71,7 @@ static struct drm_driver driver = {
 	.lastclose = radeon_driver_lastclose,
 	.unload = radeon_driver_unload,
 	.vblank_wait = radeon_driver_vblank_wait,
+	.dri_library_name = dri_library_name,
 	.irq_preinstall = radeon_driver_irq_preinstall,
 	.irq_postinstall = radeon_driver_irq_postinstall,
 	.irq_uninstall = radeon_driver_irq_uninstall,

drivers/char/drm/radeon_drv.h

@@ -103,8 +103,8 @@ enum radeon_family {
 	CHIP_R100,
 	CHIP_RS100,
 	CHIP_RV100,
-	CHIP_R200,
 	CHIP_RV200,
+	CHIP_R200,
 	CHIP_RS200,
 	CHIP_R250,
 	CHIP_RS250,

drivers/char/drm/via_drv.c

@@ -29,6 +29,10 @@
 
 #include "drm_pciids.h"
 
+static int dri_library_name(struct drm_device *dev, char *buf)
+{
+	return snprintf(buf, PAGE_SIZE, "unichrome");
+}
 
 static struct pci_device_id pciidlist[] = {
 	viadrv_PCI_IDS
@@ -61,6 +65,7 @@ static struct drm_driver driver = {
 	.irq_uninstall = via_driver_irq_uninstall,
 	.irq_handler = via_driver_irq_handler,
 	.dma_quiescent = via_driver_dma_quiescent,
+	.dri_library_name = dri_library_name,
 	.reclaim_buffers = drm_core_reclaim_buffers,
 	.get_map_ofs = drm_core_get_map_ofs,
 	.get_reg_ofs = drm_core_get_reg_ofs,